A. This section includes the requirements for the following chemical feed systems:

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1 SECTION CHEMICAL FEED SYSTEMS PART 1 - GENERAL 1.1 SUMMARY A. This section includes the requirements for the following chemical feed systems: 1. Alum. B. This specification covers the supply, installation, and testing of completely functional metering pump systems including accessories and appurtenances as shown on the drawings and described herein. A single chemical metering pump manufacturer shall be responsible for supplying all components of the metering feed system. 1.2 RELATED DOCUMENTS: A. Drawings and general provisions of Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section. 1.3 SUBMITTALS A. CONTRACTOR shall submit the following information. 1. Product Data, including: a. Manufacturer s literature b. Engineering data including materials, size, weight, performance data, flow rate, power requirements, etc. c. All electrical wiring diagrams and installation information. 2. Shop drawings B. CONTRACTOR shall submit Operations and Maintenance Data in accordance with this Specification. 1.4 QUALITY ASSURANCE A. Chemical feed system shall be provided a single supplier. Supplier shall be responsible for complete setup of all skid mounted equipment and shall shop-test all equipment for capacity and pressure prior to shipment. Supplier shall provide a written report of this testing to the ENGINEER. 1.5 WARRANTY CHEMICAL FEED SYSTEMS

2 A. The chemical metering pump manufacturer shall provide a two-year warranty on the metering pump mechanical drive and one year on the liquid end and pump accessories. PART 2 - PRODUCTS 2.1 MANUFACTURERS A. The chemical systems shall be as provided by the following manufacturer s: 1. Prominent Fluid Controls. 2. Grundfos 3. Engineer Approved equal. 2.2 GENERAL A. All systems shall be skid/enclosure mounted unless otherwise specified. B. All programming shall be coordinated with the systems integrator for the project in accordance with Specification. 1. If there is not a system integrator for the project, the supplier shall coordinate all controls with the ENGINEER and OWNER. C. All electrical work shall be in accordance with Division 26 of these specifications. D. CONTRACTOR shall be responsible for all additional pipe, taps, valves, etc. to place the skid system in service that may not be shown on the drawings. E. All feed systems that require potable water shall be protected with a backflow preventer. F. All ferrous metal shall be shop primed in accordance with this specification>. 2.3 LOCAL CONTROL PANEL A. Each skid shall be provided with its own local control panel mounted and pre-wired. Local disconnect is provided by duplex receptacle with weatherproof cover mounted on the skid proper. Enclosures shall be NEMA 4X FRP construction. B. The pump control panels shall provide all the functions and interfaces as shown on the specification P&ID s, including but not limited to the following features: Main circuit breaker and branch circuit breakers as needed. C. Each pump shall have the following devices mounted on the door of the control panel for operator interface: L-O-R Illuminated selector indicating running status, pump general alarm light, Local speed control digital potentiometer, and actual speed indication when pump is provided with analog output option CHEMICAL FEED SYSTEMS

3 D. Each pump shall have the following signals available for the plant SCADA / PLC via hard wire connection: Pump running status, pump alarm status, Pump speed analog feedback, and remote mode selected status. E. Each pump shall accept the following signals from the plant SCADA / PLC via hard wire connection: Dry contact pump enable, Analog 4-20mA speed command. F. All components shall be UL listed or Recognized, door mounted devices shall be NEMA 4x, 22mm, Heavy Duty, Oil Tight, and instrumentation shall also be NEMA 4X rated. G. Control panels shall be assembled to NFPA 79 standards and good engineering practices. 2.4 Solenoid Driven METERING PUMPS A. DESCRIPTION 1. The chemical metering pumps shall be microprocessor-controlled, simplex, solenoiddriven, reciprocating, mechanically actuated diaphragm type. All pumping functions shall be set by a membrane-switch keypad and pump status shall be displayed on an illuminated LCD which is readable at an offset angle of 45 degrees. Keypad will allow for simple scrolling and display of programmed parameters. The housing shall be rated NEMA 4X. 2. The pump shall be fully tested to meet rated flow and pressure by the manufacturer. 3. The power supply shall be 115 VAC, 60 Hz, single phase. The microprocessor is to automatically compensate for supply voltage variations within 15% of the rated voltage such that the frequency of the pump remains constant. 4. The liquid end shall be physically separated from the drive unit by a back plate with weep hole creating an air gap. An elastomer shaft wiper seal shall prevent contamination of the solenoid if the primary diaphragm fails. 5. The diaphragm shall be constructed of a steel core, vulcanized into nylon-reinforced EPDM, with PTFE-faced fluid contact surface. It shall be of a convex design fitting into a concave liquid end to minimize dead volume and promote flow of solids in suspension. 6. The pump shall utilize technology whereby the time sequence of the dosing flow can be exactly matched to the requirements of the application. The user can set a slow pressure stroke for almost continuous dosing, or a quick stroke as needed to prevent incomplete filling of the liquid end due to viscosity of the media being pumped. In cases of outgassing dosing media, the settable suction stroke shall assist in preventing cavitation. Fluctuation in backpressure shall be automatically compensated by the drive. 7. The pump shall have technology integrated into the drive to detect blocked metering points or broken metering lines, and to detect airlocks within the delivery unit. This will function to prevent uncontrolled metering. These problems are to be shown on the pump delay. B. LIQUID END 1. The liquid end shall be constructed of PVDF with Teflon seals, with built-in coarse valve and needle valve for air bleed, manually adjusted for continuous degassing of process fluid and self-priming against pressure. C. PROGRAMMING AND CONTROL CHEMICAL FEED SYSTEMS

4 1. Stroke length control shall be manually adjusted between 100%and 0% with a stroke adjustment knob on the pump face control. The LCD shall digitally display stroke length setting in 1% increments in the full range between 100% and 0%. 2. Programming shall allow pump to be calibrated so as to display pump output in gallons/hour or liters/hour. Calibration shall be maintained when stroke length is altered up to plus or minus 10% on the stroke length knob. If stroke length is altered by more than 10%, a yellow warning light will light and a flashing message calib will appear. 3. The pump shall be equipped with the programmable function of pressure levels to allow pump to operate at reduced pressures from the maximum rated pressure of the pump 4. The pump shall be equipped with the programmable function of the electronic interlocking of the keypad by access code to prevent unauthorized adjustments to the pump 5. Keypad shall allow for scrolling and display on LCD such parameters as stroke frequency, stroke length, stroke counter, pump output in gals/hr or l/hr, dosing quantity, ma current input being received by pump and indication of external mode. 6. Stroke frequency control shall be manually adjusted by touch keypads, with the set stroke rate displayed on the LCD. The metering pump shall be capable of receiving a pulse input via optional external control cable such that 1 pulse gives 1 pump stroke rate. The pump shall be capable of remote ON-OFF operation using the pause function via a voltage free contact relay through an optional control cable. 7. ANALOG The pump shall accept an analog signal such that stroke frequency is proportional to 0/4-20mA or 20-4/0mA, the choice of which is programmable at the pump. The pump shall allow the setting of a maximum stroke rate proportional to signal strength below that rate. Programming for curve processing shall also be possible, in which any stroke frequency ratio in proportion to the electrical signal can be configured. Analog to digital converters to the pump shall not be allowed. D. FLOW ASSURANCE 1. Relay Output An SPDT relay shall be installed for E. ACCESSORIES a. Fault indication. The metering pump shall have an integral relay to allow remote annunciation of a fault condition (i.e. low chemical supply in thank/lack of chemical supply shut down, flow monitor, system faults, and fuse/power supply failure). Configure as a ((NO/NC)) contact closure relay. 1. The pumps shall be mounted in an enclosure constructed of fusion welded UV-resistant white polypropylene sheets with a minimum thickness of ½. Colors other than white polypropylene shall not be acceptable. The enclosure shall have Plexiglas sliding doors to access the piping and pumps. Hinged doors shall not be acceptable. The enclosure shall be self-supporting. A single chemical metering pump manufacturer shall be responsible for supplying and assembling all components of the enclosure, in addition to testing the system under conditions of maximum rated pump pressure, prior to shipment. The enclosure shall include the following accessories, pre-piped; 2. A Saf T Flo Corporation stop solution injection valve shall be provided for each injection point. Shipped Loose for contractor to install. 3. A universal control cable with 5-pole round plastic connector and 5-wire cable with loose ends shall be provided with each pump CHEMICAL FEED SYSTEMS

5 4. An adjustable-pressure, diaphragm type back pressure/antisiphon valve shall be provided with each metering pump. 5. An inline, adjustable pressure, diaphragm type pressure relief valve shall be provided with each metering pump. 6. An air-charged, bladder type pulsation dampener shall be provided with each metering pump. 7. A clear PVC calibration column with FNPT fittings top and bottom shall be provided with each pump/skid. 8. SCADA/Termination Panel mounted on the skid and wired to the metering pumps. 9. Exhaust Fan and louvres with thermostat control. The exhaust fan shall be designed to maintain the temperature in the enclosure below 100 degrees Fahrenheit. Fan and louvres shall be of construction resistant to chemical used. F. APPLICATION 1. Quantity: 1 Skid/ enclosure, Three Pumps, dual discharge 2. Chemical Service: Alum 3. Capacity (U.S. gph): Back Pressure (psig): 145 PART 3 - EXECUTION 3.1 EXAMINATION A. Verify that dimensions are correct and project conditions are suitable for installation. Do not proceed with installation until unsatisfactory conditions have been corrected. 3.2 SHIPPING, HANDLING, DELIVERY, AND STORAGE A. The Contractor shall assume responsibility for packaging to prevent damage during site storage. 3.3 INSTALLATION A. All equipment shall be installed in accordance with approved submittals and manufacturer s recommendations. B. All systems shall be tested prior to shipment to the project site. Manufacturer or supplier shall provide written results of this testing. C. CONTRACTOR shall be responsible for all additional installation of pipe, valves, etc. for a complete project installation. CONTRACTOR shall also use appropriate material for installation based on type of chemical being pumped. 3.4 STARUP, TESTING AND TRAINING CHEMICAL FEED SYSTEMS

6 A. CONTRACTOR shall give 30 days of notice to the ENGINEER and OWNER prior to startup of chemical feed systems to allow for shipment of the chemicals. Startup and training by chemical feed equipment factory representative shall be arranged and provided by the Contractor. B. Manufacturer shall provide factory authorized representative for a minimum of 1 full week total startup time for all chemical feeds systems together. Manufacturer shall also provide a written startup report that will be submitted by the CONTRACTOR to the ENGINEER. C. Manufacturer shall provide a minimum of 1full day of training the OWNER S personnel on operations and maintenance for each chemical feed system provided END OF SECTION CHEMICAL FEED SYSTEMS