RO System Design & CSMPRO v6.0 Program

Transcription

1 RO System Design & CSMPRO v6.0 Program

2 CONTENTS 1 System Design 2 CSMPRO v6.0 Introduction 1

3 1 System Design 2

4 Consideration of Feed Source, Application The membrane system design depends on Feed Source, Feed Quality, Feed/Product Flow, and Required Product Quality. Water Source Feed Quality Flowrate Product Quality Well water Surface water Sea water Waste water SDI, TSS, TDS COD, BOD, TOC Pretreatment Type Feed / product Flowrate Recovery Application Membrane Model 3

5 Selection of configuration and No. Passes Single Pass System Double Pass system The standard flow configuration, where the feed water is passed once through the system. Combination system of two conventional RO system where permeate of the first system becomes the feed for the second system. It is used to produce ultra pure water for semi-conductor and pharmaceutical and sea water desalination. 4

6 Selection of configuration and No. Passes Concentrate Recirculation Dilution of the feed of the 1 st pass by the 2 nd pass brine improve the permeate water quality. (4% reduction) and decrease specific energy. (5% reduction) Reduction of the feed flowrate as much as that of the 2 nd pass reduce the system capacity and increase system recovery. Permeate Blending The system, where some ratio of feed water or permeate of 1 st pass is mixed to final product. The smaller system can be achieved. 5

7 Membrane Type Selection Membranes are selected by Feed Concentration, Fouling Tendency, Required Rejection and Energy Requirements. Feed Concentration Under 1,000 mg/l ; BL series Under 10,000 mg/l ; BN, BE Under 50,000 mg/l ; SHN, SHA, SHF Application Softening, Concentration, 1 st Pass of Seawater ; NF Wastewater reuse, Zero discharge ; FEn, FL, FLR Ultra pure water, Hero System ; HUE, UL Energy Requirements Low pressure requirement ; BL, FL, UL Normal pressure requirement ; BE, FEn, HUE High pressure requirement ; BR, SHN, SHA, SHF Membrane Dimension 1 m3/hr 2m3/hr 3 m3/hr 4 m3/hr 5 m3/hr Under 4040 Size 8040 Size 6

8 Determining of Average Flux The average permeate flux should be determined by the Feed Water Quality (SDI) as well as Feed Water Sources Kinds of feed water source RO Permeate Well Water Surface Water Filtered Municipal Effluent (Wastewater) MF or UF Pretreatment Conventional Well or MF Seawater Open intake SDI < 1 < 3 < 3 < 5 < 3 < 5 < 3 < 5 Average Flux (gfd)

9 Calculation of the No. of membranes & PV For the Surface Feed Water (SDI < 5), to get 100 m3/hr of the product water Determine the average flux Design guide lines : gfd Choose : 12 gfd Determine module size and grade Module size : 8 membrane Grade : RE8040-BE (Area : 400 ft 2 ) Calculation flowrate per one module 400 ft 2 /element x 12 gfd = 4,800gpd / element = 757l/hr How many vessels (6 elements/vessel) are required 133 elements 6elements/vessel = vessels are required How many RE 8040-BE elements are required 100,000 l/hr 757l/hr/element = elements 133 elements are required Qp NE = f * SE Nv = NE NE/PV NE : The number of elements Qp : The design permeate flowrate f : The design flux Nv : The number of pressure vessel NE/PV : The number of elements per pressure vessel 8

10 Determining of System Array The number of stages is a function of the planned system recovery, the number of elements per vessel and the feed water quality. Designed system recovery depends on feed water source and quality in general For the Sea water feed : 30-60% For the Brackish water feed : 75-85% For the RO permeate feed : 85-95% Array on system recovery Less than the 50% Recovery : one array Less than the 80% Recovery : two array over 80% Recovery : three array For the RO permeate : System is designed to get 90% recovery with 2 array For the Waste water : System is designed to get 75% recovery with 3 array 9

11 Feed Water Guideline Component Unit Max. level Comments & conditions SDI 1 5 MFI 1 4 Target <1 Oil & Grease mg/l 0.1 Target = 0 TOC mg/l 3 COD mg/l 10 BOD mg/l 5 Free Chlorine mg/l 0.1 Synthetic organic compounds(soc) have generally more adverse effects on RO/NF membranes compared with natural organic matters(nom) Recommends removing residual free chlorine by pre-treatment prior to membrane exposure. TSS mg/l 1 Target=0 Ferrous iron (Fe 2+ ) Ferric iron (Fe3+) Manganese Aluminum mg/l 4 ph<6, oxygen <0.5ppm mg/l 0.05 These accelerate oxidation of membrane under existing an oxidizing component in feed water. 10

12 Saturation Limits Scale or foulant LSI or SDSI (calcium carbonate) Normal Maximum Reported CSM alarm Calcium Sulfate 230% 400% 230% Strontium Sulfate 800% 1,200% 800% Barium Sulfate 6,000% 8,000% 6,000% Calcium Fluoride 100% 12,000% 100% Silica 100% 130% 100% Iron Not alarm 5ppm Not alarm Aluminum Not alarm 4ppm Not alarm LSI (Langlier Saturation Index) LSI is a method of reporting the scaling or corrosive potential of low TDS brackish water based on the level of saturation of calcium carbonate. SDSI (Stiff Davis Saturation Index) SDSI, in similar fashion as LSI, is a method of reporting the scaling or corrosion potential of high TDS seawater based on the level of saturation of calcium carbonate. 11

13 Consideration in Design Improve product quality - Use part or all seawater elements for brackish feed water - Use seawater elements in one or both stages of double pass system - Recycle permeate of last stage into feed - Use Split partial blending in double pass system Increase system recovery - Feed the concentrate to a second system, after specific pretreatment - Recycle the concentrate to feed stream Obtain high system recovery and uniform permeate flow - Use booster pumps between stages to compensate for osmotic pressure increase - Use permeate back pressure from first to last stage - Use Hybrid system design with tighter membranes in the first stage than in the second stage Reduce the plant capacity to obtain just the required permeate quality - Blend the permeate with feed water 12

14 Desalination cost Typical Costs for a Reverse Osmosis Plant * Source: Desalination With A Grain of Salt,

15 Desalination cost Evolution of the electrical consumption for seawater 1 st pass RO 14

16 Split Partial Blending Split Partial Blending? Permeate is collected from both sides of the pressure vessel. Low TDS front permeate is than sent directly to final product line, while higher TDS back permeate is treated by partial second pass RO plant. 1. Blending Double Pass RO System 2. Split-Partial Double pass RO System Advantages of Split Partial 1. Smaller first & second pass RO trains 2. Better permeate quality than blending 3. Reduced capital & operating cost 4. Flexibility in system operation according to actual conditions 15

17 Split Partial Blending 1. Fixed split ratio : by installing a permeate plug after 3 rd or 4 th RO membrane 2. Variable Split Ratio : utilizing flow control valves to control permeate split ratio 16

18 Hybrid Hybrid? To optimize feed pressure and system salt rejection, several kinds of membranes are installed to one pressure vessel. Vessel (Single Stage) Installed Membrane Permeate Quality TDS (mg/l) Expected Power Consumption (kwh/day) Single Hybrid Single Hybrid A B C SHN 6 EA ,158 SHA 6 EA ,951 SHF 6 EA ,204 SHN 2 EA + SHA 3 EA + SHF 2 EA ,834 SHN 4 EA + SHF 3 EA ,237 SHF 2 EA + SHA 3 EA + SHN 2 EA ,222 D SHF 4 EA + SHN 3 EA ,379 17

19 2 System Design 18

20 Major Features 1. New Features Energy Recovery Device option is added Support of energy consumption result Br and PO 4 ions are added 2. Improved Prediction Accuracy Concentration correction factors are updated ph correction factors are updated All of scale saturation data are updated 3. Improved NF Design A high concentration feed is applicable Improvement of convergence error 4. Improved User interface Revised Hybrid Option Changed the layout for user convenience 5. Various Output Print Save in PDF, Word, Excel, PowerPoint format 19

21 Registration 1. CSMPRO live update agent will appear on the screen to download recent version 2 User can set a preference as left dialog box to use this program easily. User information, preferred units, and languages are able to set and/or change with this windows. [Option] [Preference] on the head menus 20

22 System Design Project Note Case Information Area 2. Project Information Area 3. Unit Area 21

23 System Design - Feed 1. Select feed water source. 3. Conductivity will be calculated automatically, but it s not exact. There is no exact conversion factor between TDS and Conductivity. 2. Feed water concentration. Using TDS term or Ionic concentration 4. ph of feed water Temperature of feed water 6. Using this button to balance ion concentration between anion and cation Additional feed water quality. No use for calculation but for understand the feed water condition 8. Scale Calculation Area (See the next page) 22

24 System Design Feed Scale Calculations 1 1. System Saturation Information ph is able to adjust with option [ ph Adjustment ] 2. Execution Buttons [ Calculation ] button must be clicked to activate, after all kinds of acting 2 3. Softening By using this option, almost Ca 2+, Mg 2+ will changed into Na ph Adjustment By using this option, Chemical consumption can be calculated 23

25 System Design System 1. Choose a single pass / double pass 1 2. Design parameters Projection result 2 4. Options ph Adjustment for 2 nd pass feed and/or final product 6. Brief of flow diagram 3. Array Configurations 24

26 System Design Cost 1. Toggle buttons for pass selection Capital Cost 3 3. Membrane Replacement Operation Cost Check box should be selected to insert values. 5. Energy Recovery Device 25

27 Result Diagram Flow Diagram with brief information After click a [ RESULT ], the program will show a this diagram. Some information including flow rate, TDS, pressure, flow diagram and recovery is demonstrated on the results. For more details, choose a [ Result Scan ] Tab. 26

28 Result Result Scan Errors and Warnings Overall projection data 2. Toggle buttons for pass and each array data 3. Overall pass information 4. Each pass or array details 5. Ionic concentration information for selected pass or array 7. Saturation Information Limitation Warning Limitation tool tip will be appeared when mouse pointer locate on a red values which exceeded than limitation in Each pass or array details 4 and saturation information 7 27

29 Result Cost Unit Conversion 2. Overall Information 3 3. Capital Cost 4. Operation Cost 4 Cost Analysis It provides capital and operation cost of each block and specific cost Pre & Post chemical consumption is based on each flow rate. 28

30 Print Out 1. Save 2. Print Overview of each format 3. Page Option Several Option to use it easily. Save as PDF, Excel, PowerPoint, Word format Directly print out. 29