Innovative Hydraulics 915 Valley View Avenue Pittsburgh, PA (412)

Transcription

1 VISUAL WATER DESIGNER USER MANUAL Version 1.1 Water/Wastewater Design Software 915 Valley View Avenue Pittsburgh, PA (412) All rights reserved.

2 Visual Water Designer 2 Copyright: , ; all rights reserved. No part of this manual or the associated software may be copied, illegally stored, transmitted, or translated into any computer language, in any form or by any means, without express written consent from. Disclaimer: Visual Water Designer has been thoroughly tested by in an attempt to produce an error free application. However, no representation or warranties are made, express or implied, in regards to the Visual Water Designer software or the contents of the user manual. In no event shall be held liable for any damages, loss of data, loss of property, or loss of profits arising out of the use of this software. This product was created to be a tool to aid the designer and should not be used as a substitute for proper engineering practice.

3 Visual Water Designer Contents 3 Table of Contents Section Page I. Introduction a. System requirements 5 b. Program installation 5 c. Visual Water Designer capabilities 10 d. Program help 10 II. III. IV. Program features a. The main screen 15 b. Program icons 15 c. Program menu options 17 d. User provided data 25 e. Results screen 30 f. Theory/assumptions screen 36 g. Specialties screen 39 h. Creating/using trials 40 Pumping/Hydraulics options a. Pumps 44 b. Full flow pipe 54 c. Open channel 57 d. Orifice/gate 61 e. Weir 64 f. Flume 67 g. Flow measurement devices 69 h. Sewers 71 i. Culverts 74 Standard treatment unit options a. Clarifiers/Sedimentation tanks 78 b. Aeration tanks 80 c. Trickling filters 82 d. Disinfection (chemical) 84 e. Screening 86 f. Grit removal 88 g. Digesters 90 h. Sludge thickeners 92 i. Flocculation 94 j. Filtration 96 k. Rotating biological contactors 98 l. Belt filter press 100

4 Visual Water Designer Contents 4 m. Centrifuge 102 n. Dissolved air floatation 104 o. Vacuum filtration 106 V. Advanced treatment units a. Membrane filtration 109 b. Reverse osmosis 111 c. Ultraviolet disinfection 113 d. Phosphorus removal 115 e. Nitrogen removal 117 VI. Theory 119

5 Visual Water Designer Introduction 5 System Requirements In order to install Visual Water Designer, the target computer must meet the following requirements: - Running Windows 95 or higher or Windows NT 3.51 or higher - Operating at a screen resolution of 800 x 600 or higher. Lower resolutions (such as 640 x 480) may not display the entire screen. - Hard drive with at least 15 MB of free space - 16 MB RAM - Mouse (or other pointing device) - Printer (in order to obtain hard copy results of any analysis) - Microsoft Internet Explorer version 3 or higher (for viewing help files) Program Installation PART I - INTRODUCTION In order to use Visual Water Designer it must be installed on the target computer s hard drive. This is done by extracting the program and its associated files from the Visual Water Designer software CD. The following procedure should be followed to install Visual Water Designer on your computer directly from the software CD: - First, it s recommended that you close out of all other applications before attempting to install the program. - Insert the Visual Water Designer CD into your computer. - The install procedure should be initiated once the CD has been inserted into the CD ROM drive. If it does not, you have to initiate the install process yourself hit the Start button at the bottom of the screen, and choose Run. The following box will appear: - In the Open: box type the letter of the drive containing the program CD followed by :\setup.exe (as shown above). Then hit the OK button. - This will initiate the Visual Hydraulics setup program. The setup program contains an installation procedure that creates a directory on your hard drive where all the required files are stored. The installation program will also create a shortcut icon to the program on your desktop. The default location for this directory is in the Program files folder on your hard drive. The initial installation screen appears as follows:

6 Visual Water Designer Introduction 6 If you exit out of the setup process at any time (such as hitting Cancel), the following warning message will appear: If setup is exited before the installation is complete, the setup program may be run at another time to complete the installation. The program will not run correctly if the installation program is not completed. Choose Next on the initial setup screen, and this forwards the user to User and Product Information screen. This screen is shown below:

7 Visual Water Designer Introduction 7 This screen requires the Name of the Licensee, Company that purchased the Software, and Product ID Number that was provided with the CD packet. A valid Product ID number must be entered onto this screen or the setup program will not install Visual Water Designer. The letters in the Product ID Number are case sensitive. If an invalid Product ID Number is entered in the setup screen, the following message will appear: Once the appropriate information is provided and a valid Product ID Number is entered, the installation program will display the End User License Agreement, which is a standard agreement for any typical software installation. The choice is given for accepting or not accepting the agreement. If the agreement is not accepted, the install program will not continue. The license agreement form is shown as follows:

8 Visual Water Designer Introduction 8 Upon accepting the agreement, you will be forwarded to the next step, which allows you to specify the start menu folder the program will be located in: Unless you want to change the name of the folder, hit next. The next step allows you to specify whether or not a desktop icon is created on your computer:

9 Visual Water Designer Introduction 9 Keeping this box checked will create an icon on your desktop that provides a direct link to the program. The install program will now have all the information it needs to install Visual Water Designer on your machine. Clicking Install on the following form will run the installation process, and Visual Water Designer will then be installed on the target computer.

10 Visual Water Designer Introduction 10 Visual Water Designer Capabilities Visual Water Designer was developed as a comprehensive design tool that covers a wide variety of hydraulic, process, utility, and general water/wastewater features. The software has been broken down into three main categories, including hydraulics and pumping, standard treatment design, and advanced treatment design. For the pumping and hydraulics portion of the software, the user may analyze various features of pumps, full flow pipes, open channels, orifices/gates, weirs, flumes, flow measurement devices, sewers, and culverts. The standard treatment portion of the software allows the user to analyze the most common design parameters of clarifiers, aeration systems, trickling filters, chemical disinfection, screening devices, grit removal devices, digesters, sludge thickeners, flocculation basins, filtration systems, rotating biological contactors, belt filter presses, centrifuges, dissolved air floatation systems, and vacuum filtration systems. In addition to the standard treatment section of the software, Visual Water Designer also has an advanced treatment section that allows the user to analyze some of the more advanced technologies currently being employed in water treatment today. These processes include membrane filtration, reverse osmosis, UV disinfection, phosphorus removal, and nitrogen removal. Visual Water Designer was created recognizing that processes are continually changing and new processes are being developed. As the needs of the designer change, Visual Water Designer will continue to evolve into a practical tool that provides design assistance for all types of water features. Program Help Extensive help is provided throughout the program. The help files that are shipped with Visual Water Designer are in the standard Windows help format. Program help may be accessed in a variety of ways. On the main screen, the main menu may be used:

11 Visual Water Designer Introduction 11 By selecting the Help topics option, the main help file will be displayed: Update The contents tab provides a general grouping of the topics available in the help file. Double clicking on any of the topics will bring up the individual topics under that section: In order to view all the help topics available in the help file, simply access the Index tab on to top of the form, and the topics will be displayed in alphabetical order:

12 Visual Water Designer Introduction 12 Double clicking on any topic or highlighting a topic and selecting the Display button will access that particular help file:

13 Visual Water Designer Introduction 13 Many of the help topics will have links to other topics. Links are always underlined and usually follow the content of the topic. They provide a quick means of jumping easily to other related subjects: In addition to the help provided on the main screen, help options are provided throughout the program. Some of the forms have a Help button, which provides a direct link to the help topic related to the section of the program that is currently being used:

14 Visual Water Designer Introduction 14 In this case, the program would link the designer directly to the help file for using the software s conversion tool:

15 Visual Water Designer Program Features 15 PART II PROGRAM FEATURES The Main Screen The program s main screen is displayed when the program is opened: Program icons The software s various features are accessed through the icons that are displayed on the top left corner of the screen:

16 Visual Water Designer Program Features 16 A description of each icon can be found by placing the mouse overtop of that particular icon: As was previously mentioned, the software has been broken down into three main categories: hydraulics and pumping, standard treatment design, and advanced treatment design. The icon list shown in the figure above is for the standard process design category. To switch between categories, simply use the Design menu item on the main screen: Selecting the Pumping/Hydraulics menu option then displays the icons for that category:

17 Visual Water Designer Program Features 17 Program menu options The Options menu item provides the user with three menu selections, Project Properties, View Assumptions, and the Fitting / K Value Database : The Project Properties option allows the user to specify the system of measure used by the software for all calculations (English or SI) and the default units of flow that will be used where flow rate is required for a calculation: The View Assumptions option will display for the user all of the assumptions that are used by Visual Water Designer in performing the various calculations available in the software. This item is a very important tool and should be consulted by the designer:

18 Visual Water Designer Program Features 18 As can be seen, the program lists for the user all of the assumptions used for the various hydraulic and treatment features available within the software. The user may change any of the assumptions at any time. The values provided in the software are based on numerous sources and industry standards, but it may be desired to change a value depending on the design situation. Using the Project Assumptions form is discussed further in detail later in this section of the user manual. The final item under the Options menu is the Fitting K /Value Database option. Selecting this option will display for the user the software s pipe fitting database. This database contains all of the fittings and their respective K values, which apply to the pipe and pumping design portions of the program. The database is a working database, in that it can be altered to suit the user s needs at any time. Fittings can be added, removed, and if desired, fitting K values can also be changed for any fitting in the database. The fitting database form appears as follows:

19 Visual Water Designer Program Features 19 To change a K value for any fitting, the user simply has to highlight the fitting from the list and supply the desired K value in the box provided. For example, if the user wishes to change the K value for a standard 90 degree bend from 0.25 to 0.3, that fitting is highlighted in the list, and the new K value is supplied: Selecting the Apply button will change the K value from the selected fitting to the value provided. To remove an unwanted fitting from the database, highlight that fitting in the list, then select the Delete fitting button. A confirmation message will be provided to make sure that the fitting is actually to be permanently removed from the database: To add a fitting that is not in the database, a section of the form has been provided that allows the user to supply a fitting description and that fitting s K value: Selecting Apply after the description and K value have been provided then adds the new user specified fitting to the fitting database:

20 Visual Water Designer Program Features 20 The fitting database is also discussed in the pipe and pumping section of the user manual. The Tools menu item contains a few specialty features, including a conversions calculator, flows calculator, water properties tool, and a link to the standard Windows calculator: The Water Properties tool simply provides an option that allows the user to specify a water temperature and the software will then provide the various physical properties of water at that temperature. The Conversions tool provides the user with a built in conversion function that can convert values from most of the common units for length, flow, temperature, power, and pressure. This tool is shown as follows:

21 Visual Water Designer Program Features 21 The user simply selects the parameter to convert (flow in the example above), the units to convert From and To, and the quantity to convert. The conversion is then performed by selecting the Convert button provided on the form. The Flow Calculator tool provides the user with the ability to calculate total runoff/discharge from a defined area. The software provides the user with the two most commonly accepted methods for determining runoff, the Rational Method and the SCS Discharge Method. This form is shown as follows:

22 Visual Water Designer Program Features 22 For the rational method, the user must supply the characteristics of the drainage area, including the sub-areas that contribute to the overall discharge and the runoff coefficient of each area. Additionally, the rainfall contributing to the overall discharge must be provided. To enter individual sub-areas, the user simply has to enter the size and runoff coefficient for each sub-area in the boxes provided: When the user selects Add, the new sub-area is then added to the total sub-areas provided for the watershed:

23 Visual Water Designer Program Features 23 Once all of the sub-areas have been entered and the rainfall has been specified, the total discharge from the watershed can be determined by selecting the Calculate Discharge button: For the SCS Discharge Method, the process of determining the overall discharge is basically the same, with a few different requirements. Below is the tab provided for the SCS Discharge Method: For the SCS Discharge method, the user must also supply the time of concentration for the watershed and the type of rainfall, which is area dependent. Sub-areas and curve numbers are

24 Visual Water Designer Program Features 24 added by following the steps described for the Rational Method. Once all of the data is supplied, the discharge is determined by selecting the Calculate Discharge button: The final option available under the Tools menu item is the standard Windows calculator, which is shown when the Windows Calculator option is selected: The last menu item is the Help option, which provides a link to all of the program s help files. The About Visual Water Designer item simply pulls up a summary form that contains information about the program and its copyrights. A link is also provided which will connect the user to the website. The User Manual link will open this user manual directly from within the software. The help files were described in more detail earlier in this manual.

25 Visual Water Designer Program Features 25 User provided data When the user has selected which feature to analyze, the software will request the necessary required input from the user so for the analysis. This will obviously vary considerably depending on the feature to be analyzed and the calculation to be performed. Some calculations only require a few pieces of data, while others require considerably more input. The best way to look at how the software requests data is to look at a few examples. Consider the analysis of a circular final clarifier. The first step would be to select the Standard Treatment Units section of the software by using the Design drop down menu: This will then bring up the standard treatment units options on the main screen, from which the clarifier option can be chosen:

26 Visual Water Designer Pumping/Hydraulics Options 26 Selecting the clarifier button then updates the main screen accordingly: The main screen is then populated with a diagram of a clarifier, options requesting the shape of the clarifier, and a section that requests the calculation parameter to be analyzed by the software and the required user input for that calculation. The Tank Shape frame provided at the lower portion of the screen is only displayed if it is needed by the software for the analysis of a particular treatment process. Some processes do not have standards shapes, such as filter presses, screening devices, rotating biological contactors, centrifuges, and vacuum filtration systems. If one of these standard process features is being analyzed, the Tank Shape frame is simply hidden since it does not apply. The following diagrams break down the various sections of the main screen: Feature diagram and tank shape tanks shape is only required on processes where shape is needed for the calculations

27 Visual Water Designer Pumping/Hydraulics Options 27 Active trial if multiple trials have been analyzed for a particular feature, the trial that is currently active User input section based on the calculation parameter selected (in this case detention time), the required data is requested from the user in this section of the main screen Evaluate button instructs the software to perform the calculation once the required input data has been provided New Trial button begins a new trial for the analysis being performed Help button brings up the help file for the active feature The parameters that are available to be calculated by the software are listed in the drop down box at the top of the user data input section: Based on the parameter selected, the software will update the user required input accordingly. For example, if Solids loading rate is requested to be analyzed, the main screen is then updated accordingly:

28 Visual Water Designer Pumping/Hydraulics Options 28 The format of the software in terms of the required user input is very similar for almost all of the features available. There are a few features that have such a varying required amount of input that specialized user input sections had to be established for these features. These features are the full flow pipe and the pump. Both of these options are available as part of the Pumping/Hydraulics section of the software: If the pumping option is selected for analysis, the user input section would appear as follows:

29 Visual Water Designer Pumping/Hydraulics Options 29 In this case, because of the variety of information required from the user to analyze a pumping system, the required user input is much more in depth than other features. Similarly, the data required for full pipe analysis is as follows:

30 Visual Water Designer Pumping/Hydraulics Options 30 A more detailed discussion of all of the features available from the software in terms of calculation parameters available and user input required for those calculations is discussed in subsequent sections of this user manual. User input errors As is common with any standard software application, errors are caught and handled by the software depending on the type of error that may occur. Typical errors are flagged when a user enters a non-numeric value or value less than zero, unless a value less than zero is acceptable. If such an error occurs, the user may see a message similar to one of the following: Other error handlers were built into the program to alert the user that a value out of the acceptable range of values was supplied. An example of this error could generate a message similar to the following: If error messages such as these are encountered, the user supplied input should be checked for accuracy. The user will not be allowed to continue until acceptable values have been provided for all of the input data. The Results Screen Once the required data has been provided by the user for a particular feature parameter, the calculation will be performed on the input that has been provided. As was mentioned previously, the software will perform the calculation when the Evaluate button is selected:

31 Visual Water Designer Pumping/Hydraulics Options 31 In order to examine the results screen features, consider the following example. The user wants to analyze the detention time of a circular clarifier with the following characteristics: Diameter: 80 ft Depth: 15 ft Flow: 8 MGD The user would then input the characteristics into the main screen as follows: When this data has been provided and the Evaluate button is selected, the software analyzes the data and provides the results on the Results screen:

32 Visual Water Designer Pumping/Hydraulics Options 32 As a note, the results screen is simply a tabbed form which is part of the main screen. The user can toggle between the results screen and main screen by using the tabs at the top of the form: The Results screen has three main sections, a section which summarizes the data provided by the user, a section which displays for the user the results of the calculation, and a graph which analyzes the parameter to be calculated over a range of values. In the example, the detention time is graphed over a range of flows. This range spans values of zero to twice the design flow. One of the flexible features provided with Visual Water Designer is the option for the user to switch between different units for the end result. This option is available for the majority of the calculations provided in Visual Water Designer. Not all calculations will have this option, and it

33 Visual Water Designer Pumping/Hydraulics Options 33 depends on the type of calculation being performed. In this example, the available units for the result are shown next to the result summary: In this case, the units for detention time are displayed in hours. Simply use the drop down menu to select the desired units: If minutes is the option chosen as the desired units for the result, the summary form adjusts for the new unit of measure and is updated accordingly: The final object on the Results screen is the Calculation Summary Report button:

34 Visual Water Designer Pumping/Hydraulics Options 34 One of the unique features of Visual Water Designer is that is provides for the user a report which summarizes the design equations used in the analysis of any calculation so that the user can physically see how the results were obtained. This report can then be printed or exported to a variety of applications, including Microsoft Word (.doc files) and Adobe Reader (.pdf files). Using the previous example for the circular clarifier detention time calculation, if the Calculation Summary Report option is chosen from the Results screen, the report for that calculation will then be displayed:

35 Visual Water Designer Pumping/Hydraulics Options 35 Exporting and saving a report Once a particular report has been generated, it may be saved in a variety of formats. These include the rich text file format (.rtf), Microsoft Word format (.doc), and Adobe Reader format (.pdf). In order to save a report, simply click the export report option on the report toolbar: This will bring up the exporting options dialog box, which supplies the option of choosing a particular file format for saving the report: In this case, the.pdf format is chosen for saving the file. The program will then provide a standard save dialog box: The report will then be saved in the chosen format at the location specified.

36 Visual Water Designer Pumping/Hydraulics Options 36 The Theory/Assumptions Screen The third tab available at the top of the main screen is the Theory/Assumptions tab. This tab becomes active and available whenever a calculation is performed by the software. The Theory/Assumptions screen contains a listing of the assumptions used in the calculation (if any), recommended design parameters for the feature being analyzed (based on industry standards), and a theory section that actually contains a compilation of the equations/tables/theory used in the calculations for the active feature. The Theory/Assumptions tab is shown as follows: Selecting this tab then brings up the Theory/Assumptions screen: The screen above is shown for the clarifier detention time example. In the case of clarifiers, no assumptions are required by the software for any clarifier calculations. The recommended parameters for clarifiers are summarized in the tables provided at the bottom of the screen. The clarifier theory section is presented at the top right of the screen, which contains a summary of clarifier theory and equations used in the calculations. To view the theory in its entirety, the user simply has to use the scroll bar to the right of the theory to navigate up and down.

37 Visual Water Designer Pumping/Hydraulics Options 37 If assumptions are used by the software for a particular feature, they will be listed in the Calculation Assumptions portion of the screen. For example, for the flocculation feature, the assumptions are listed as follows for the required paddle area calculation: As was previously discussed, the assumptions used by Visual Water Designer are based on industry standards and have been compiled from a variety of sources. But they still are assumptions, and the user may desire to change these values. Assumptions can be changed at any time by the user. As can be seen from the diagram above, there is a Check Assumptions button that will forward the user to a compilation of the assumptions used for the feature being analyzed, in this case a flocculation basin: This form provides the user with all of the assumptions for the feature being analyzed. If a different value for an assumption is desired, simply enter that value in the appropriate box provided and when finished select the Save Changes button provided on the form. This will then update the assumptions and from that point forward the software will utilize the values provided by the user. It should be noted that saving an assumption instructs the software to use that value from that point on for any calculations performed. The user may revert to the default assumptions that are incorporated into the software at any time. These are the values that are in the software the first time the program is run. To restore the defaults for the current feature being analyzed, simply use the Restore Defaults button

38 Visual Water Designer Pumping/Hydraulics Options 38 provided on the form. The user will be prompted with a warning message to confirm that this action should be performed: In addition to accessing the assumptions used by the software for the feature being analyzed, the entire database of assumptions can be accessed by the user at any time from the main screen. This can be done using the drop down menus: This will then bring up the assumptions form, with all of the assumptions used by Visual Water Designer: Accessing the assumptions in this manner will also allow the user to change or restore any of the assumption values at any time.

39 Visual Water Designer Pumping/Hydraulics Options 39 File saving and assumptions When a file is saved, the assumptions are also saved with that file. So if an analysis is performed on a particular feature with a different assumption value than the default assumptions, when the file is opened that user defined value will be used by the software for the calculations. The Specialties Screen The final tab available on the main screen is the Specialties tab. This tab was built into the program to accommodate any additional features that the software would offer to the user when analyzing a particular feature. Some features are much more complicated in design than others, and therefore more design features are made available for their analysis. Additionally, some design features are very common and used much more frequently than others, so additional design options were built into the software for these features. For example, if a pump is being analyzed by the user, the Specialties tab will become active. In the case of a pumping analysis, various additional analyses are available, including pump power determination, variable speed analysis, and pump operational cost analysis. More detail is provided regarding the specialties options available for each particular feature in the breakdown of the features available later in the user manual.

40 Visual Water Designer Pumping/Hydraulics Options 40 Creating/using trials One of the unique features of Visual Water Designer is the ability to create up to ten different trials for any particular analysis. This is available for all of the features in the program. The active trials box is shown on the left side of the main screen: The active trial list shows the trial that is currently active for the feature being analyzed. By default, the first analysis performed for any feature is trial number 1. New trials that are added are numbered sequentially. A new trial can be added at any point, but it should be noted that data is not saved for a trial unless the evaluation is actually performed. Consider the following example for trial runs used in the analysis of the detention time in a clarifier. When a new clarifier analysis is performed, the software automatically displays the first analysis as trial 1 : When the data is entered for the clarifier and the Evaluate option is chosen, the software automatically stores that clarifier data in trial 1. If the user wishes to try another trial, the New Trial button is then selected:

41 Visual Water Designer Pumping/Hydraulics Options 41 Selecting the New Trial option will display the following message to the user: The user has two options for creating a new trial. The active trial (in this case trial 1) can be copied as a starting point for the next trial, or the data can be completely erased and the user can start with fresh data. In this case, let s assume the user wants to use completely different data, so No is chosen. This then creates trial 2 and erases the data used in trial 1 :

42 Visual Water Designer Pumping/Hydraulics Options 42 New data can then be entered for the new trial. Again, the data for the trial will only be saved when the actual evaluation is performed. Once multiple trials have been added, the user may toggle between any of the trials simply by using the drop down list on the form: Trials may also be removed at any time. To remove a trial, simply select that trial from the drop down list and use the Remove Trial button. This will permanently delete that trial from the list of active trials. There must be at least one trial in place at all times.

43 Visual Water Designer Pumping/Hydraulics Options 43 PART III PUMPING/HYDRAULICS OPTIONS The pumping/hydraulics portion of Visual Water Designer covers a variety of hydraulic features, including pumps, full flow pipes, open channels, orifices/gates, weirs, flumes, flow measurement devices, sewers and culverts. To access the pumping/hydraulics section of the software, the Design drop down menu is used: This then displays the icons for the pumping/hydraulics features, which then allow the user to access any of the features directly: The user manual will now go through each of the features offered in the pumping/hydraulics portion of the software.

44 Visual Water Designer Pumping/Hydraulics Options 44 Pumps This section of the manual reviews the methods used by the program to analyze pumping systems. Careful analysis is critical in the design of pumps and errors can be very costly. Conservative designs should be performed that account for a certain degree of error as well as the knowledge that the methods used in sizing pumps are by no means exact. This program performs pumping analyses by calculating the total discharge head (TDH) required and net positive suction head (NPSH) available for a pump to successfully transport flow through a userdefined system. Many other options are available as well, such as determining pump power requirements, operating costs, and affinity law evaluations, which predict how a pump will perform based on varying speeds. The main pump screen appears as follows: In order to evaluate a pumping system, the software must be provided with the static discharge head, static suction head, flow to be pumped, and the static and discharge pipes that comprise the pumping system. Consider a simple pumping system with one suction pipe and one discharge pipe. First, the user would supply the known characteristics for the heads and flow:

45 Visual Water Designer Pumping/Hydraulics Options 45 Once the heads and flow have been specified for the pumping system, the next step is to begin adding the suction and discharge pipes. To add a new suction or discharge pipe, use the New Pipe button located beneath both pipe list boxes: This will bring up the form that allows the user to enter all of the characteristics of the new pipe: The user provides the pipe diameter, pipe length, friction loss method to be used and corresponding friction factor, and flow through the pipe. Once this has been completed, the user can then specify the fittings for the pipe. This is performed using the fitting database provided on the form:

46 Visual Water Designer Pumping/Hydraulics Options 46 The fittings are added simply by using the Add button. If a fitting that been added is to be removed, simply highlight the fitting in the list titled Fittings added to this pipe and select the Remove button, and the fitting will be removed. When fittings are added, they are displayed in the box provided on the form: Once all of the fittings have been added and all of the pipe characteristics have also been specified, select the Add Pipe button at the bottom left corner of the form to add the new suction pipe to the pumping system:

47 Visual Water Designer Pumping/Hydraulics Options 47 As can be seen from the diagram above, the pipe has now been added to the pumping system. Once a pipe has been added, its features can be changed at any time. To edit an existing pipe, simply highlight that pipe in the list, then select the Edit Pipe button. This will bring up the pipe form with all of the specified pipe characteristics: Changes can then be made to the existing pipe, if desired. Note: At the bottom of the pipe form is a link to the software s Fitting / K Value database: The same process can be followed for adding the discharge pipe to the pumping system. Under the discharge pipes list box use the New Pipe button to specify the characteristics of the discharge pipe:

48 Visual Water Designer Pumping/Hydraulics Options 48 Fittings are added in the same manner as was described for the suction pipe. Once the characteristics of the discharge pipe are added, the Add Pipe button adds the new discharge pipe to the pumping system:

49 Visual Water Designer Pumping/Hydraulics Options 49 When all of the pipes have been added for the pumping system, the system can be evaluated. This is done by selecting the Evaluate button on the main screen: In this case, when the evaluation is performed by the software, the results screen is shown as follows: The previous example looked at a pumping system pumping a flow with no solids. Options are also provided for pumping two different kinds of sludges, primary sludge and secondary/digested sludge. Depending on the type of sludge and the solids content of the sludge, the software will assign a friction multiplier to the pipe loss calculations that will account for the additional friction caused by pumping flow with a significant solids content. The option to specify pumping solids is provided at the bottom of the main design form:

50 Visual Water Designer Pumping/Hydraulics Options 50 To specify a solids content in the flow, the user has to choose the type of sludge to be pumped and the estimated solids content of the flow. If the previous example is used for primary sludge at 3% solids, the results would appear as follows, which shows a significant increase in the friction losses and head requirements of the pump: In addition to the calculation of the pump system requirements such as TDH and NPSH, the software also offers additional options on the Specialties tab:

51 Visual Water Designer Pumping/Hydraulics Options 51 On this form, the user may determine the various powers required for operation of the pump (output power, brake power, and electric power), and how pump speed will affect the pump s flow, head, and power requirements. Finally, a section is provided for determining the pump operating costs based on the amount of time the pump is expected to run and the cost of electricity to run the pump. For example, if the pump and motor efficiencies are supplied in the Pump Power Determination section, the program will calculate the various powers required based on the pump s system characteristics:

52 Visual Water Designer Pumping/Hydraulics Options 52 The affinity law calculations are performed by supplying the software with the pump s design speed and flow and head capacities: Based on these values, the software will then determine the resulting pump capacity, head capacity, and power requirements over a range of speeds:

53 Visual Water Designer Pumping/Hydraulics Options 53 The final option available on the pump specialties form is the cost to run the pump. The user provides the length of time the pump runs, either in hours per day or hours per week, as well as the local electric costs in $/KW hr. Using the characteristics calculated by the software for the pumping system, the software will predict the cost of running the pump for the operational parameters supplied: Calculation assumptions to consider: Calculation assumptions made by the software for a pumping system are the liquid specific gravity, atmospheric pressure, vapor pressure, and temperature of the flow being pumped:

54 Visual Water Designer Pumping/Hydraulics Options 54 Pipes Full flow pipes are one of the most common hydraulic features encountered in water design. Visual Water Designer will analyze the hydraulics associated with full flow pipes based on the user provided data, which includes the pipe characteristics, pipe fittings, and flow through the pipe. The user selects the pipe option from the Hydraulics/Pumping section of the software: This then displays for the user the pipe design form: In order for the software to analyze the hydraulics of pipe flow, the user must provide the friction loss method to be used by the software (Hazen-Williams, Darcy-Weisbach, or Manning s Equation), the appropriate friction factor, pipe diameter, pipe length, and total flow through the pipe. The user must also specify the pipe fittings. Consider a pipe with the following characteristics:

55 Visual Water Designer Pumping/Hydraulics Options 55 Friction factor: Hazen-Williams C value of 100 Pipe length: 500 ft Pipe diameter: 36-inches Fittings: Entrance, four 90 degree bends, exit Flow: 5 MGD This data would then be provided on the form as follows: Fittings are simply added by selected the fitting from the list of fittings provided, supplying the total number of fittings, then selecting the Add button : In addition to the main pipe characteristics, options are also provided for analyzing flows with solids. To specify a solids content in the flow, the user has to choose the type of sludge and the estimated solids content of the flow:

56 Visual Water Designer Pumping/Hydraulics Options 56 Once all of the pipe data has been provided, the user can select the Evaluate button to analyze the pipe: Calculation assumptions to consider: No calculation assumptions are made by the software for pipes.

57 Visual Water Designer Pumping/Hydraulics Options 57 Open Channels Open channels are also extremely common in hydraulic applications. The user selects the open channel option from the Hydraulics/Pumping section of the software: The open channel design form is then displayed for the user: The open channel design feature provides the user with three calculation options: determining the flow in the channel, determining the depth in the channel at a specified length away from a known or starting depth, and determining the slope of the channel if the flow and depth are known. The calculations for determining flow and channel slope are fairly straightforward, with the Manning s equation being the methodology used by Visual Water Designer to analyze open channels. Determining a channel depth at a specified length away from a known or starting depth is a much more complex hydraulic problem. Visual Water Designer analyzes all channel

58 Visual Water Designer Pumping/Hydraulics Options 58 depth calculations as gradually varied flow problems. Rapidly varied flow conditions involving hydraulic phenomena such as hydraulic jumps are difficult to predict and are not considered in this software. The direct step method is used to determine upstream or downstream depths away from a known starting depth. This methodology is discussed in much greater detail in the theory section towards the end of the user manual. However, an example and discussion of how Visual Water Designer analyzes open channel depths is provided here as a basis of understanding. Consider the following channel: Shape: Rectangular Flow: 50 cfs Width: 4 feet Manning s n value: Slope: ft/ft (0.1%) Known depth: 5 feet Length from known depth: 1000 feet The channel above is actually a channel with a control point downstream, let s say in this case a weir. The depth of flow at the weir is known. The user wishes to determine the depth 1000 feet upstream of the weir in the channel. The analysis begins by selecting the Channel depth option and providing the required data on the form: Once all of the channel data has been provided, the Evaluate button is selected to perform the analysis. The results are presented as follows:

59 Visual Water Designer Pumping/Hydraulics Options 59 Since the normal depth is greater than the critical depth, the profile is considered Mild. The starting depth is greater than the normal depth, so depth will actually decrease upstream from the known downstream starting depth. Again, the various flow profiles that are possible and the calculation methodology is covered in much more detail in the theory section of this manual. A few notes about the open channel flow depth calculations. Depending on the type of flow profile present in the channel, the calculation may proceed downstream or upstream of the known starting depth. This is set by the channel profile. As can be seen from the summary form above, the calculated depth location is upstream of the starting depth. For steeply sloped channels (critical depth greater than normal depth) the calculation must proceed downstream, it cannot start downstream and proceed upstream, because it would present an unstable condition. For mildly sloped channels, the calculation starts downstream and proceeds upstream. The same is true of horizontal channels and channels with adverse slopes. In certain instances, the software will actually set the known starting depth based on the starting depth provided. This will occur if the known starting depth provided will produce an unstable flow condition (some form of rapidly varied flow). For example, consider the following data provided by the user:

60 Visual Water Designer Pumping/Hydraulics Options 60 This is basically the same channel data that was used in the previous example, however in this case the user specifies a starting channel depth of only 1 foot, as opposed to the starting depth of 5 feet used in the previous example. When this channel is analyzed, the software provides the user with the following message: In this case, if the starting depth is actually at a depth as low as 1 foot, an unstable condition will occur and rapidly varied flow will prevail. A hydraulic jump will occur at some point in the channel since the starting depth is less than the critical depth. Visual Water Designer catches this unstable condition and will use the critical depth in the channel as the starting depth, which will result in a stable gradually varied flow condition. Calculation assumptions to consider: No calculation assumptions are made by the software for open channels.

61 Visual Water Designer Pumping/Hydraulics Options 61 Orifices/Gates The Orifice/Gate option allows the designer to determine the head loss that will result or flow that will be conveyed through any type of opening or orifice(s). Common examples are baffles, settling ports, flow diffusers, and gates. Head loss is a function of the velocity of the flow passing through the opening, the orifice shape (usually circular or rectangular), and the level of submergence. Flow through an orifice is dependent on the upstream head and the shape of the orifice. The user selects the orifice/gate option from the Hydraulics/Pumping section of the software: The orifice/gate design form is then displayed for the user:

62 Visual Water Designer Pumping/Hydraulics Options 62 In the case of the orifice/gate analysis, the user can select one of two options for the software to analyze, either the head loss resulting from a flow through an orifice or the flow through the orifice that will result from a user provided upstream head (loss): Consider the following two scenarios: Orifice shape: Circular Orifice diameter: 24-inches Flow through orifice: 4 MGD Parameter to determine: Orifice head loss For this scenario, the Calculate loss option is chosen from the drop down box. The values are then entered into the boxes provided, and the Evaluate produces the following results: For the second scenario, considering the following orifice characteristics:

63 Visual Water Designer Pumping/Hydraulics Options 63 Orifice shape: Rectangular Orifice size: 24-inches x 24-inches Upstream head: 1.5 feet Parameter to determine: Flow through orifice First, the user should select the Calculate flow option from the drop down box: The values are then entered into the boxes provided, and the Evaluate produces the following results: Calculation assumptions to consider: Calculation assumptions made by the software for an orifice or gate are the orifice/gate C values:

64 Visual Water Designer Pumping/Hydraulics Options 64 Weirs Weirs are flow control devices that are used to measure flow, equalize flow distribution, or establish set water levels in a treatment plant. They are very common at tank outlets and flow splits. Visual Water Designer offers the designer the ability to analyze 6 different types of weirs triangular (v-notch), rectangular, sharp crested, Cipolletti (trapezoidal), contracted, and broad crested. The user may either analyze the head over the weir if the flow is known or the resulting flow over the weir if the head is known. The user selects the weir option from the Hydraulics/Pumping section of the software: As was previously mentioned, in the case of a weir analysis the user can select one of two options for the software to analyze: either the head over the weir resulting from a known flow value or the flow over the weir that will result from a user provided weir head: Calculation assumptions to consider: No calculation assumptions are made by the software for weirs. Consider the following weir to analyze: Weir type: Sharp crested Weir invert: 700 Weir length: 3 feet Flow over weir: 1200 gpm If these values are entered into the boxes provided, the user can then instruct the software to determine the head over the sharp crested weir at 1200 gpm:

65 Visual Water Designer Pumping/Hydraulics Options 65

66 Visual Water Designer Pumping/Hydraulics Options 66 The following C values are used for the six different types of weirs that may be analyzed by the software: Weir Type English C Value Metric C Value V-notch Rectangular Sharp Crested Cipolletti (Trapezoidal) Contracted Broad Crested

67 Visual Water Designer Pumping/Hydraulics Options 67 Flumes Flumes are open channel flow measuring devices that are very common in treatment plant applications. Flumes operate by restricting the flow through the throat area to create a flow condition that is easily correlated to a head value. Visual Water Designer offers the designer the ability to analyze four types of flumes Parshall, Cutthroat, Rectangular, and Trapezoidal. Parshall flumes are probably the most common because of their relatively simple construction, low maintenance, and reliability. The user may either analyze the head over through the flume if the flow is known or the resulting flow through the flume if the head is known. The user selects the flume option from the Hydraulics/Pumping section of the software: As was previously mentioned, in the case of a flume analysis the user can select one of two options for the software to analyze: either the head through the flume resulting from a known flow value or the flow through the flume that will result from a user provided flume head: Calculation assumptions to consider: No calculation assumptions are made by the software for flumes. Consider the following flume to analyze: Flume type: Parshall flume Flume invert: 700 Flume throat width: 2 feet Flow through flume: 800 gpm If these values are entered into the boxes provided, the user can then instruct the software to determine the head resulting from the 800 gpm flow through the flume:

68 Visual Water Designer Pumping/Hydraulics Options 68

69 Visual Water Designer Pumping/Hydraulics Options 69 Flow Measurement Devices Flow measurement devices typically operate by restricting the flow area as it passes through the device, creating a pressure drop. This pressure drop can then be correlated to a flow value depending on the amount of drop experienced by the device. Flow measurement devices that can be analyzed using Visual Water Designer are the Venturi meter, Venturi nozzle, circular orifice meter, and rectangular orifice meter. The user may either analyze the head loss through the flow measurement device if the flow is known or the resulting flow through the flow measurement device if the head loss is known. The user selects the flow measurement option from the Hydraulics/Pumping section of the software: As was previously mentioned, in the case of a flow measurement analysis the user can select one of two options for the software to analyze: either the head loss through the flow measurement device resulting from a known flow value or the flow through the device that will result from a user provided device head loss: Calculation assumptions to consider: Calculation assumptions made by the software for the flow measurement devices are the C coefficients for Venturi meters, circular orifice meters, and rectangular orifice meters: Consider the following flume to analyze: Flow meter type: Venturi meter Influent pipe diameter: 36-inch Venturi meter throat diameter: 18-inch Flow through meter: 4 MGD

70 Visual Water Designer Pumping/Hydraulics Options 70

71 Visual Water Designer Pumping/Hydraulics Options 71 Sewers Sewers are circular conduits used to carry storm or sanitary flow, and at times even a combination of both in combined systems. Sewers are typically designed to operate as open channels in a partially full condition, yet it is not uncommon for sewer systems to full flow and surcharge under peak flow scenarios, especially older systems that were not properly designed to convey the amount of flow entering the sewer system. Visual Water Designer analyzes sewer sections by considering flow conditions at a downstream section and determining the resulting flow characteristics at a user chosen upstream section. The user selects the sewer option from the Hydraulics/Pumping section of the software: The main design screen for the analysis of a sewer section is shown as follows:

72 Visual Water Designer Pumping/Hydraulics Options 72 As was previously mentioned, the software uses a known downstream starting condition to evaluate the sewer upstream of that section. The user must supply the sewer length, diameter, upstream and downstream inverts, Manning s n of the sewer material, and flow through the sewer. Additionally, the user must supply a base starting depth downstream for the analysis. This can either be the critical depth in the sewer (minimum energy), or a user supplied starting depth: If the critical depth is chosen as the downstream starting depth, the software will determine this critical depth based on the flow and size of the sewer. If the user selects to provide a starting depth, it must be provided on the form: A typical sewer analysis may appear as follows:

73 Visual Water Designer Pumping/Hydraulics Options 73 Based on the data provided for the sewer, the software determines the condition of the flow in the sewer at the upstream section: In this case, the critical depth downstream is 0.75 feet. For the conditions provided, the normal depth is less than the critical depth, so supercritical flow conditions exist for this sewer section. The upstream depth is actually the critical depth, since flow must pass from normal depth through critical depth at the sewer entrance. If the software is analyzing a sewer section and determines that the sewer will flow full for part of the length of the sewer or over the entire length of the sewer, both open channel equations and full flow pipe equations are required to determine the upstream depth. Numerous flow conditions may exist in sewers that are dependent on a variety of factors, and the analysis of unusual flow conditions can be quite complex. A detailed discussion of the various flow conditions that may exist in sewers and how they are determined by Visual Water Designer is discussed in the theory section of the user manual. Calculation assumptions to consider: No calculation assumptions are made by the software for a sewer analysis.

74 Visual Water Designer Pumping/Hydraulics Options 74 Culverts Culverts are specialized pipe/sewer applications that typically operate hydraulically as open channels. They are designed to convey flow from one side of an obstruction to another by passing flow through the obstruction. Roadways are the most typical example of culvert use. In addition to the general design considerations of pipes and open channels, site specific conditions that exist as part of a culvert design must be taken into consideration because of the significant effect those site conditions may have on the hydraulics of a culvert system. Good examples of these site considerations are the headwater and tailwater elevations upstream and downstream of the culvert. Visual Water Designer offers the user the ability to analyze the two most common shapes of culverts, circular and rectangular (box). The equations and methodology used in analyzing the culverts are based on the design manuals established by the Federal Highway Administration (FHWA) and adopted by most state transportation agencies. The culvert design screen appears as follows:

75 Visual Water Designer Pumping/Hydraulics Options 75 In addition to the standard characteristics to be provided for the culvert, the user must also select the type of inlet upstream of the culvert entrance from the drop down list provided on the main design form: Similar to the analysis of a sewer, the user must provide a tailwater depth at the outlet of the culvert. The user can select to use the critical depth, which assumes that there are no backwater effects on the flow exiting the culvert, or supply a specific user defined tailwater depth. If the critical depth is to be used, once the culvert s characteristics are entered the Use yc depth button can be selected, and the critical depth will be provided in the tailwater depth box: Once all of the required culvert characteristics are provided by the user, the evaluation of the culvert can then be performed, with the results provided by the software:

76 Visual Water Designer Pumping/Hydraulics Options 76 For the summary of the culvert, the graph provided is the headwater rating curve, which looks at the minimum and maximum headwaters over a range of flows. This range is set from 0 to twice the design flow provided by the user. The design summary also includes the EL hi and EL ho elevations, which define how the culvert is controlled, either by upstream characteristics or downstream characteristics. A more detailed of the culvert methodology used by the software to analyzing culverts is discussed in the theory portion of the user manual. Calculation assumptions to consider: No calculation assumptions are made by the software for a culvert analysis.

77 Visual Water Designer Pumping/Hydraulics Options 77 PART IV STANDARD TREATMENT UNITS The standard treatment units portion of Visual Water Designer covers the majority of treatment units/processes encountered at a water/wastewater treatment facility. These processes include clarifiers, activated sludge systems, trickling filters, disinfection (chemical), screening devices, grit removal systems, thickeners, flocculation systems, filtration systems, rotating biological contactors, centrifuges, belt filter presses, dissolved air floatation systems, and vacuum filtration systems. To access the standard treatment units section of the software, the Design drop down menu is used: This then displays the icons for the standard treatment units, which then allow the user to access any of the features directly: The user manual will now go through each of the features offered in the standard treatment units portion of the software.

78 Visual Water Designer Pumping/Hydraulics Options 78 Clarifiers Clarifiers are used in treatment plant applications to settle and remove solids from the flow. Clarifiers may exist at multiple locations within a treatment process to enable different types of solids to be removed from the treatment system. Visual Water Designer allows the user to analyze five different operating parameters for clarifiers Detention time, Surface overflow rate, Weir loading rate, Solids loading rate, and Required surface area: Parameter Definitions: Detention time The amount of time that it takes for flow to pass entirely through the clarifier. Surface overflow rate The ratio of the flow through the clarifier to the clarifier s surface area. Weir loading rate The ratio of the flow through the clarifier to the clarifier s total weir length. Solids loading rate The ratio of the amount of solids entering the clarifier over a given period of time to the clarifier s surface area. Required surface area Based on the solids loading, the required area needed for the clarifier to satisfy the clarifier s recommended solids loading rate. For clarifiers, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the clarifier being analyzed. This section of the design form is provided at the bottom left of the screen: The main design screen appears as follows for a clarifier:

79 Visual Water Designer Pumping/Hydraulics Options 79 Calculation assumptions to consider: No calculation assumptions are made by the software for a clarifier analysis.

80 Visual Water Designer Pumping/Hydraulics Options 80 Activated Sludge Activated sludge systems are biological processes that metabolize the organics in wastewater. Activated sludge processes involve the introduction of air into the system in order for the microorganisms to break waste down and sustain the biological activity. Visual Water Designer allows the user to analyze seven different operating parameters for activated sludge systems Required aeration volume, Return activated sludge rate, Solids retention time, Food to mass ratio, Sludge wasting rate (mass based), Sludge wasting rate (flow based), and Oxygen requirements: Parameter Definitions: Required aeration volume The volume of the aeration system required based on flow and BOD loading rate. Return activated sludge rate The rate of flow that should be returned from the secondary process back to the activated sludge system. Solids retention time The average length of time that the solids mass (microorganisms) remain in the activated sludge and secondary system (including return flow). Food to mass ratio The ratio of food (soluble BOD) to mass (microorganisms MLSS or MLVSS) in the activated sludge system. Sludge wasting rate The rate of excess sludge flow that should be removed from the activated sludge system. Oxygen requirements The amount of oxygen required for the microorganisms to metabolize the organics in the wastewater, typically expressed in lb/day or kg/day. For activated sludge systems, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the aeration tank(s) being analyzed. This section of the design form is provided at the bottom left of the screen:

81 Visual Water Designer Pumping/Hydraulics Options 81 The main design screen appears as follows for an activated sludge system: Calculation assumptions to consider: Calculation assumptions made by the software for activated sludge systems are the BOD oxidation requirement and NH3 oxidation requirement which are utilized in the Oxygen requirements calculation:

82 Visual Water Designer Pumping/Hydraulics Options 82 Trickling Filters Trickling filters are fixed film media biological processes. Trickling filters are one of the most simplistic biological treatment processes, using the natural flow of air and constant dosing of waste over the fixed media film that allows the microorganisms to thrive naturally. Visual Water Designer allows the user to analyze six different operating parameters for trickling filters Organic loading, Hydraulic loading, Flushing intensity, BOD reduction using NRC equations, BOD reduction using Germain/Schultz equations, and Distributor rotational speed: Parameter Definitions: Organic loading The rate of BOD loading per volume of trickling filter media. Hydraulic loading The ratio of flow through the trickling filter to the trickling filter surface area. Flushing intensity The amount of flow distributed to the trickling filters by the trickling filter arms per revolution. BOD reduction (NRC) The amount of BOD that will be removed in the trickling filters as determined by the NRC equations. BOD reduction (Germain/Schultz) The amount of BOD that will be removed in the trickling filters as determined by the Germain/Schultz equations. Distributor rotational speed The amount of time it takes the distributor to make one full pass around the trickling filter. For trickling filters, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the trickling filter being analyzed. This section of the design form is provided at the bottom left of the screen: The main design screen appears as follows for a trickling filter:

83 Visual Water Designer Pumping/Hydraulics Options 83 Calculation assumptions to consider: No calculation assumptions are made by the software for a trickling filter analysis.

84 Visual Water Designer Pumping/Hydraulics Options 84 Disinfection Disinfection processes are used in treatment systems to remove harmful bacteria, pathogens, and viruses from the effluent water before it is used or discharged into waterways. Common chemicals used for disinfection include chlorine, ozone, and chlorine dioxide. Visual Water Designer allows the user to analyze five different operating parameters for disinfection systems Detention time, CT values for chlorine, CT values for chlorine dioxide, CT values for ozone, and Required retention time: Parameter Definitions: Detention time The amount of time that it takes for flow to pass entirely through the disinfection system. CT values for chlorine The product of chlorine concentration times exposure time which is used as a measure of the level of chlorine disinfection required. CT values for chlorine dioxide The product of chlorine dioxide concentration times exposure time which is used as a measure of the level of chlorine dioxide disinfection required. CT values for ozone The product of ozone concentration times exposure time which is used as a measure of the level of ozone disinfection required. Retention time The actual amount of time the flow should be retained based on the baffling available in the disinfection system. For disinfection systems, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the tank(s) being analyzed. This section of the design form is provided at the bottom left of the screen: The main design screen appears as follows for a disinfection system:

85 Visual Water Designer Pumping/Hydraulics Options 85 Calculation assumptions to consider: Calculation assumptions made by the software for disinfection systems are the baffling factors chosen for the Required retention time calculation:

86 Visual Water Designer Pumping/Hydraulics Options 86 Screening Devices Screening devices such as bar racks are typically used in treatment application to remove larger unwanted debris from the process flow. They are usually found at the head of treatment plant applications, but are also fairly common in solids processing as well for large debris removal. Visual Water Designer allows the user to analyze three different operating parameters for screening devices Screen head loss, Design channel depth, and Expected screenings volume: Parameter Definitions: Screen head loss The difference in depths downstream and upstream of the screening device that results from a change in velocity as flow passes through the screen. Design channel depth The required channel depth to meet a target velocity for flow passing through a screening device. Expected screenings volume Based on the flow rate through the screen and spacing of the screen bars, an estimate of the expected volume collected from screening over a period of time. The main design screen appears as follows for screening devices:

87 Visual Water Designer Pumping/Hydraulics Options 87 Calculation assumptions to consider: No calculation assumptions are made by the software for a screening analysis.

88 Visual Water Designer Pumping/Hydraulics Options 88 Grit Removal Grit removal systems are typically placed at the head of treatment systems to remove grit from the flow before it enters equipment that can be subject to abrasion, such as pumps. Grit systems can function as vortex chambers or modified settling tanks. Visual Water Designer allows the user to analyze four different operating parameters for screening devices Grit settling velocity, Grit scour velocity, Required length/diameter, and Grit storage time available: Parameter Definitions: Grit settling velocity The time it will take a specified type of grit to settle a determined depth. Grit scour velocity The velocity at which a specified type of grit and grit diameter will produce scouring effects. Required length/diameter Based on the desired settling velocity of the grit, the length or diameter of tank required to ensure that settling occurs. Grit storage time available Time available for storage of grit based on the amount of grit produced and the available grit storage volume. The main design screen appears as follows for grit removal systems:

89 Visual Water Designer Pumping/Hydraulics Options 89 Calculation assumptions to consider: Calculation assumptions made by the software for grit removal systems are the grit drag coefficient used for the Grit settling velocity calculation: Additionally, the grit scour constant and grit friction factor used for the Grit scour velocity calculation:

90 Visual Water Designer Pumping/Hydraulics Options 90 Digesters Digestion is widely used to stabilize the organic matter in sludge prior to ultimate disposal. Digestion can be an aerobic process or anaerobic process, depending on the treatment processes used and the types of sludges to be stabilized. Visual Water Designer allows the user to analyze six different operating parameters for digesters Aerobic digester volume, Anaerobic digester volume, Volatile solids loading, Digestion/retention time, Expected VSS reduction, and Aerobic digester air requirements: Parameter Definitions: Aerobic digester volume The digester volume required for an aerobic digester system based on the sludge characteristics provided. Anaerobic digester volume The digester volume required for an anaerobic digester system based on the sludge characteristics provided. Volatile solids loading The ratio of volatile solids applied to the digester per unit volume of digester. Digestion/retention time Total time that the sludge is held in the digester, which is dependent on the digester volume and sludge flow rate. Expected VSS reduction Estimate of the volatile suspended solids that will be reduced depending on the age of the sludge and the sludge temperature. Aerobic digester air requirements Total air volume required per day based on the digester sludge flow and volatile solids concentration. For digesters, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the digester being analyzed. This section of the design form is provided at the bottom left of the screen:

91 Visual Water Designer Pumping/Hydraulics Options 91 The main design screen appears as follows for digesters: Calculation assumptions to consider: Calculation assumptions made by the software for digesters are the air required for VSS destruction and sludge specific gravity used for the Air requirements - aerobic calculation:

92 Visual Water Designer Pumping/Hydraulics Options 92 Sludge Thickening Sludge thickening is the simplest process available for consolidating waste sludges. Primary sludges and waste activated sludges are typically not combined in sludge thickeners because of poor solids capture. Visual Water Designer allows the user to analyze three different operating parameters for sludge thickeners Hydraulic loading rate, Sludge detention time, and Solids loading rate: Parameter Definitions: Hydraulic loading rate The ratio of the influent sludge flow to the thickener surface area. Sludge detention time The amount of time that sludge is in the thickener before it is removed for further processing. Solids loading rate The ratio of the amount of solids entering the thickener over a given period of time to the thickener s surface area. For thickeners, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the thickener being analyzed. This section of the design form is provided at the bottom left of the screen: The main design screen appears as follows for sludge thickeners:

93 Visual Water Designer Pumping/Hydraulics Options 93 Calculation assumptions to consider: No calculation assumptions are made by the software for sludge thickeners.

94 Visual Water Designer Pumping/Hydraulics Options 94 Flocculation Flocculation is the agitation of treated water to induce coagulation. This process encourages particles to floc together to form larger particles and promote a higher degree of settling. Flocculation is the primary methodology for removing turbidity from water. Flocculation is commonly performed with paddles, baffles, or turbines. Visual Water Designer allows the user to analyze six different operating parameters for flocculation Velocity gradient, Optimum velocity gradient, Power based on gradient, Power based on paddle size, Required paddle area, and Basin detention time: Parameter Definitions: Velocity gradient Changes in the fluid velocity from point to point in the fluid being mixed. Optimum velocity gradient The velocity gradient at which a maximum value of flocculation occurs and beyond which minimal increases in flocculation are realized. Power based on gradient The power input required to impart a desired velocity gradient to a volume of liquid. Power based on paddle size The actual power imparted to a volume of liquid based on the area of paddles and characteristics of the liquid. Required paddle area Given a paddle radius and rotational speed, the paddle area required to achieve a desired velocity gradient. Basin detention time The amount of time that it takes for flow to pass entirely through the flocculation basin. For flocculation basins, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the basin being analyzed. This section of the design form is provided at the bottom left of the screen:

95 Visual Water Designer Pumping/Hydraulics Options 95 The main design screen appears as follows for flocculation basins: Calculation assumptions to consider: The calculation assumption made by the software for flocculation basins is the motor efficiency used for the Power based on gradient calculation: Additionally, the relative velocity and paddle drag coefficient are used for the Power based on paddle size calculation:

96 Visual Water Designer Pumping/Hydraulics Options 96 Filtration Filtration is the process of removing non-settleable solids from the flow by passing it through a porous medium. Typical media used in gravity filtration include sand and coal. Visual Water Designer allows the user to analyze five different operating parameters for filtration Filter head loss, Filter loading rate, Minimum fluidization velocity, Backwash rate, and Filter maximum trough depth: Parameter Definitions: Filter head loss Pressure drop (loss) that occurs as flow is passed through the voids of a porous medium. Filter loading rate The ratio of the flow passed through the filter to the filter s surface area. Minimum fluidization velocity The minimum upward velocity required through a porous surface to suspend grains in water. Backwash rate The upward flow rate through the filter required to ensure that fluidization of the porous bed occurs. Filter maximum trough depth The maximum upstream depth in a filter trough based on the size of the trough and flow through the trough. For filtration systems, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the filter being analyzed. This section of the design form is provided at the bottom left of the screen: The main design screen appears as follows for filtration systems:

97 Visual Water Designer Pumping/Hydraulics Options 97 Calculation assumptions to consider: Calculation assumptions made by the software for filtration systems are the filter media shape factor and filtration temperature used for the Filter head loss calculation: Additionally, the filtration temperature is used for the Minimum fluidization velocity and Backwash rate calculations:

98 Visual Water Designer Pumping/Hydraulics Options 98 Rotating Biological Contactors Rotating biological contactors are rotating plastic disks containing media that are partially submerged in the water and partially subjected to the atmosphere. When the unit is submerged, liquid flows into the plastic spaces, where biological growth occurs. Natural airflow and oxygen is provided when the plastic surface is exposed to the atmosphere. Visual Water Designer allows the user to analyze four different operating parameters for rotating biological contactors (RBCs) Hydraulic loading rate, Organic loading rate, Effluent BOD for single stage RBCs, and Effluent BOD for multiple stage RBCs: Parameter Definitions: Hydraulic loading rate Ratio of the flow through the RBCs to the RBC total surface area. Organic loading rate Ratio of the influent BOD loading to the RBC total surface area. Effluent BOD (single stage) The predicted effluent BOD that will result from a single stage RBC at a given flow rate, RBC diameter, and BOD loading. Effluent BOD (multiple stage) The predicted effluent BOD that will result from multiple RBC stages at a given flow rate, RBC diameter, and BOD loading. The effluent BOD from each stage is the influent BOD to the next stage in the sequence. The main design screen appears as follows for rotating biological contactors:

99 Visual Water Designer Pumping/Hydraulics Options 99 Calculation assumptions to consider: The calculation assumption made by the software for RBCs is the soluble BOD to BOD ratio for the Effluent BOD calculations:

100 Visual Water Designer Pumping/Hydraulics Options 100 Belt Filter Presses Belt filter presses use pressure to compress the sludge between porous tensioned belts. This process works to squeeze the water out of the sludge, producing a fairly dry, cake type sludge that can then be ultimately disposed of. Conditioners such as polymer are often used in the filter press process to produce sludges of higher solids content. Visual Water Designer allows the user to analyze six different operating parameters for belt filter presses Hydraulic loading rate, Solids loading rate, Polymer dosage, Filter press sizing, Operating time, and Cake produced: Parameter Definitions: Hydraulic loading rate Ratio of the sludge feed applied to the belt filter press to the belt filter press belt width. Solids loading rate Ratio of the solids loading over a period of time to the belt filter press belt width. Polymer dosage Polymer dose required based on the sludge feed rate, sludge concentration, polymer feed rate and concentration, and filter press operating time. Filter press sizing Belt width required based on the projected sludge feed, operating time, and target loading rate. Operating time Amount of time filter press must be operated to meet the target loading rate for a set sludge feed flow and belt width. Cake produced The projected weight of cake produced based on the sludge feed rate, feed concentration, and cake concentration. The main design screen appears as follows for belt filter presses:

101 Visual Water Designer Pumping/Hydraulics Options 101 Calculation assumptions to consider: The calculation assumption made by the software for belt filter presses is the sludge specific gravity used for the Solids loading rate and Polymer dosage calculations:

102 Visual Water Designer Pumping/Hydraulics Options 102 Centrifuges Centrifuges are used for both sludge dewatering and sludge thickening. Solids are removed from the influent sludge flow by subjecting the sludge to a centrifugal force hundreds of times greater than the force of gravity. The solids are deposited against the spinning centrifuge bowl, and the supernatant is drawn off. Visual Water Designer allows the user to analyze six different operating parameters for centrifuges Typical cake solids, Total power required, Centrifugal acceleration force, Design flow scale up calculation, Design length scale up calculation, and Design speed scale up calculation: Parameter Definitions: Typical cake solids Estimate of the percent cake solids produced by the centrifuge given the type of solids being dewatered and centrifugal acceleration. Total power required The power required for operation of the centrifuge based on the total operating time and the manufacturer s specific power requirement. Centrifugal acceleration force Centrifugal force (in Gs) applied by the centrifuge based on the radius of the rotating liquid and the centrifugal rotational speed. Scale up calculation (design flow) Design flow determined from the analysis of a smaller scale or test centrifuge with proportional design features to the design centrifuge. Scale up calculation (design length) Design length determined from the analysis of a smaller scale or test centrifuge with proportional design features to the design centrifuge. Scale up calculation (design speed) Design speed determined from the analysis of a smaller scale or test centrifuge with proportional design features to the design centrifuge. The main design screen appears as follows for centrifuges:

103 Visual Water Designer Pumping/Hydraulics Options 103 Calculation assumptions to consider: The calculation assumption made by the software for centrifuges is the excess capacity factor used for the Total power required calculation:

104 Visual Water Designer Pumping/Hydraulics Options 104 Dissolved Air Flotation Dissolved air flotation is a sludge conditioning process that involves the introduction of fine bubbles into the liquid by pressurized air. Particles are forced to the surface by the forced air and drawn off the top off the tank, whereas the effluent sludge exits the system well below the surface. Dissolved air flotation is more widely used for separating grease and fine particulates from the sludge. Visual Water Designer allows the user to analyze five different operating parameters for dissolved air flotation Detention time, Hydraulic loading rate, Air/solids ratio (no recycle), Air/solids ratio (with recycle), and Required surface area: Parameter Definitions: Detention time The amount of time that it takes for flow to pass entirely through the dissolved air floatation tank. Hydraulic loading rate The ratio of the flow passed through the dissolved air floatation tank to the tank s surface area. Air/solids ratio (no recycle) Ratio of units of air (typically lb or kg) to units of solids, with no recycle back through the dissolved air floatation system. Air/solids ratio (with recycle) Ratio of units of air (typically lb or kg) to units of solids, with recycle back through the dissolved air floatation system. Required surface area The dissolved air floatation tank surface area required given the flow, suspended solids, and target mass loading rate. For dissolved air flotation systems, in addition to the parameter specific items required for each analysis, the user must also specify the shape of the system being analyzed. This section of the design form is provided at the bottom left of the screen:

105 Visual Water Designer Pumping/Hydraulics Options 105 The main design screen appears as follows for dissolved air flotation systems: Calculation assumptions to consider: The calculation assumption made by the software for dissolved air flotation systems is the dissolved air fraction used for the Air/solids ratio (no recycle) and Air/solids ratio (with recycle) calculations:

106 Visual Water Designer Pumping/Hydraulics Options 106 Vacuum Filtration Vacuum filters are used for dewatering sludges by pumping the sludge through a cylindrical drum with a porous surface. The drum is partially submerged in the sludge, and as it rotates a vacuum is applied under the drum s porous surface, which draws solids to the surface and forms a solids cake. Visual Water Designer allows the user to analyze four different operating parameters for vacuum filters Vacuum filter loading rate, Vacuum filter yield, Required filter area, and Daily hours of operation: Parameter Definitions: Vacuum filter loading rate Ratio of the flow through the filter to the filter total surface area, per unit time. Vacuum filter yield Ratio of the sludge cake produced by the filter to the filter total surface area, per unit time. Required filter area The required surface area of the vacuum filter, based on sludge flow, desired cake concentration, and target loading rate. Daily hours of operation The amount of time the filter must operate on a daily basis, based on sludge flow, cake concentration, and target yield rate. The main design screen appears as follows for vacuum filters:

107 Visual Water Designer Pumping/Hydraulics Options 107 Calculation assumptions to consider: No calculation assumptions are made by the software for vacuum filtration systems.

108 Visual Water Designer Pumping/Hydraulics Options 108 PART V ADVANCED TREATMENT UNITS The advanced treatment units portion of Visual Water Designer covers some of the more advanced technologies encountered at a water/wastewater treatment facility. These processes include membrane filtration, reverse osmosis, ultraviolet (UV) disinfection, phosphorus removal, and nitrogen removal. To access the advanced treatment units section of the software, the Design drop down menu is used: This then displays the icons for the advanced treatment units, which then allow the user to access any of the features directly: The user manual will now go through each of the features offered in the advanced treatment units portion of the software.

109 Visual Hydraulics Appendix 109 Membrane Filtration Membrane filtration is a process characterized by the removal of suspended or colloidal particles by using a sieving mechanism based on the size of the membrane pores relative to the size of the particles being removed. All membranes have a distribution of pore sizes, which varies depending on the membrane material and manufacturing process. Visual Water Designer allows the user to analyze four different operating parameters for membrane filtration Transmembrane pressure (TMP), General flux, Membrane driven flux, and Recovery: Parameter Definitions: Transmembrane pressure (TMP) The passage of liquid through the membrane based on the membrane pressure gradient. General flux Filtrate flow per unit of membrane filtration area. Membrane driven flux The predicted flow across the membrane based on the pressure difference on the upstream and downstream side of the membrane and the membrane s physical characteristics. Recovery Amount of feed flow that is converted to filtrate flow. The main design screen appears as follows for membrane filtration systems:

110 Visual Hydraulics Appendix 110 Calculation assumptions to consider: The calculation assumption made by the software for membrane filtration systems is the membrane tortuosity for the Membrane driven flux calculation:

111 Visual Hydraulics Appendix 111 Membranes Reverse Osmosis The reverse osmosis pressure forces the feedwater by hydrostatic pressure through membranes, with the impurities remaining behind. The pressure difference between the two sides of the membrane is referred to as the osmotic pressure. Osmotic pressure is a function of the fluid concentration, membrane characteristics, and temperature. Visual Water Designer allows the user to analyze six different operating parameters for the reverses osmosis process Fluid flux, Salt/solute flux, Recovery, Blended (bypass) flow, Permeate TDS, and Required membrane area: Parameter Definitions: Fluid flux The passage of liquid through the membrane based on the membrane pressure gradient. Salt/solute flux The passage of salt/solute through the membrane based on the membrane pressure gradient. Recovery Amount of feed flow that is converted to filtrate flow. Blended (bypass) flow The amount of reverse osmosis product water that should be blended with the membrane feedwater to generate the required concentrations. Permeate TDS The measure of the total dissolved solids (TDS) of the membrane product (permeate) flow. Required membrane area The required membrane surface area based on the membrane feed flow, estimated recovery, and membrane flux. The main design screen appears as follows for membrane reverses osmosis systems:

112 Visual Hydraulics Appendix 112 Calculation assumptions to consider: No calculation assumptions are made by the software for membrane reverse osmosis systems.

113 Visual Hydraulics Appendix 113 Ultraviolet (UV) Disinfection UV disinfection is a growing alternative disinfection methodology to the standard chemical disinfection that is still prevalent in most treatment plant applications. UV light can be favorable for disinfection because of its ability to inactivate pathogenic organisms without forming regulated disinfection byproducts that can be harmful to water systems and are dangerous to transport and handle. Visual Water Designer allows the user to analyze six different operating parameters for UV disinfection Exposure time, Theoretical UV dose, Required UV dose, Average UV intensity, UV transmittance, and Number of lamps required: Parameter Definitions: Exposure time Ratio of the UV dose applied to the intensity of UV light. Theoretical UV dose The measure of the amount of UV energy per unit area that is incident on a surface. Required UV dose Dose required that accounts for the effects of UV lamp aging and UV lamp fouling. Average UV intensity A measure of the UV light power passing through a unit area. UV transmittance A measure of the fraction of UV light transmitted through a specific material. Required number of lamps The number of UV lamps required for disinfection based on the system flow, dose applied, volume treated per UV lamp, and target intensity. The main design screen appears as follows for UV disinfection systems:

114 Visual Hydraulics Appendix 114 Calculation assumptions to consider: Calculation assumptions made by the software for UV disinfection systems are the lamp fouling factor and lamp aging factor used for the Required UV dose calculation:

115 Visual Hydraulics Appendix 115 Phosphorus Removal Phosphorus is commonly generated by human wastes and from land runoff. The majority of phosphorus in wastewater is in solution, therefore only a small portion of phosphorus is removed using the typical sedimentation process. Other means are typically required to maximize the removal of phosphorus, such as chemical precipitation with compounds including alum, lime, and ferric chloride. Visual Water Designer allows the user to analyze four different operating parameters for phosphorus removal Liquid alum required, Lime required, Ferric chloride required, and Sludge produced from alum usage: Parameter Definitions: Liquid alum required The amount of alum required per day to remove a given concentration of phosphorus at a defined flow rate, depending on the characteristics of the alum solution. Lime required Concentration of lime required to react with the alkalinity of the wastewater and produce calcium compounds that aid in settling solids and combine with phosphates so that phosphorus can be removed. Ferric chloride required The amount of ferric chloride required per day to remove a given concentration of phosphorus at a defined flow rate, depending on the characteristics of the ferric chloride solution. Sludge produced (alum usage) Estimate of the amount of sludge that will be produced based on influent and effluent BOD, TSS, and phosphorus concentrations, as well as the alum dosage applied. The main design screen appears as follows for phosphorus removal systems:

116 Visual Hydraulics Appendix 116 Calculation assumptions to consider: Calculation assumptions made by the software for phosphorus removal systems include the alum dosage for the Liquid alum required calculation: Additionally, the ferric chloride dosage is used for the Ferric chloride required calculation: The final assumptions made for phosphorus removal are the solids produced per mg/l of BOD and organic phosphorus in biological solids for the Sludge produced alum usage calculation:

117 Visual Hydraulics Appendix 117 Nitrogen Removal Nitrogen is common in human wastes and is primarily in the form of ammonia and organic nitrogen. Biological nitrification does not necessarily remove ammonia, but does convert it to a form that is non toxic to fish. Man factors affect the nitrification process, including ammonia concentration, ph, temperature, and dissolved oxygen. Visual Water Designer allows the user to analyze five different operating parameters for nitrogen removal Oxygen required for NH4 conversion to nitrate, Alkalinity consumed by nitrification, Alkalinity required for ph control, Maximum growth rate of nitrifiers, and Minimum mean cell residence time: Parameter Definitions: Oxygen required for NH4 conversion to nitrate The amount of oxygen required for the conversion of ammonia to nitrate based on the flow and TKN concentration. Alkalinity consumed by nitrification Quantity of alkalinity (as CaCO3) that must be present for nitrification based on flow and TKN concentration. Alkalinity required for ph control In addition to the alkalinity present in the wastewater, the additional alkalinity that is required to maintain the appropriate ph level required for maintaining nitrifying organisms. Max growth rate of nitrifiers An estimate of the kinetic growth that is possible for nitrifying organisms based on the conditions of the wastewater, including influent nitrogen (as NH3-N), temperature, ph, and dissolved oxygen. Minimum mean cell residence time The minimum amount of time that the microorganisms must be subjected to the nitrogen compounds to be removed for microorganism growth and subsequent nitrification to occur. The main design screen appears as follows for nitrogen removal systems: