SECTION WATER TREATMENT

Transcription

1 SECTION WATER TREATMENT PART 1 - GENERAL 1.01 GENERAL The Bidding and Contract Requirements, Division 1 - General Requirements, Section General Provisions, and Section Basic Materials and Methods shall apply to this section SCOPE The work covered under this section shall include the furnishing of all labor, piping, valves, gauges, control panels, water meter wiring, chemicals and all other equipment required for a complete water treatment service as indicated on the drawings or herein specified QUALITY ASSURANCE The water treatment chemical equipment and service supplier shall be a recognized specialist, active in the field of industrial water treatment for the last ten years, whose major business is in the field of water treatment and shall have regional water analysis laboratories, development facilities and service department, plus full time service personnel located within the trading area of the job site SUBMITTALS Provide shop drawings on this equipment as described in Section PART 2 - PRODUCTS 2.01 WATER TREATMENT SYSTEM Provide, install and service a water treatment system for the water systems. The water treatment system shall be as manufactured by MOGUL CORPORATION. Other manufacturers fully equal to the specified manufacturer as manufactured by HYDAC, MORR, ARC, or AQUATOMIC are acceptable. A. Piping, valves, and accessories shall be furnished and installed as required by the water treatment manufacturer. B. Provide all chemicals required at system start-up and throughout the service period. Chemical formulations shall not exceed the allowable EPA or local effluent limits. C. The water treatment chemical and service supplier shall furnish basic water test equipment including carrying case and reagents for use with suppliers' products. This shall include apparatus for determination of ph, P and M alkalinity, treatment /13

2 residual, and conductivity. Where specialized or supplementary equipment is required, it shall be furnished as part of the contract. D. Condenser System Feeding and Control Equipment - Contractor shall install the following apparatus including all external piping and wiring for each condenser water system. 1. One MOGUL AUTO CHEM Model as manufactured by the MOGUL CORPORATION, for controlling Total Dissolved Solids (TDS), biological growth, inhibitor feed and chemical treatment in the cooling water system. Controller shall be U.L. Listed. Control panel shall be a single, NEMA 1 steel enclosure, primed and fully painted, and shall have the following basic features, fully pre-wired: a. Internal wiring harnessed, color-coded, clearly identified, and brought to master terminal board. b. Grounded AC receptacles for chemical treatment pump and utility use. c. Main power switch and indicating lamps, with legend plate, for power, bleed control, biocide pump, inhibitor pump and system flow. d. Line voltage safety switch - Interlock with door to shut off line voltage to control when adjustment or maintenance is required. e. Manual-Off-Auto selector switches and indicating lamps for bleed off control, chemical feed and acid feed, with legend plates. f. Manual-Off-Auto selector switch for inhibitor feed and a push button to simulate a water meter pulse in the makeup water supply line for test purposes. g. A selector switch for control of chemical feed from metered makeup. h. Conductivity controller accurate to 5% full scale with an analogindicating meter. i. Front panel fuses. j. Dual biocide feed program modules to automatically alternate between two biocides with a seven-day timer. k. A temperature compensated conductivity electrode and flow switch mounted on the side of the controller enclosure. l. Bleed lock-out timer to prevent bleed function after a biocide feed /13

3 Power and bleedoff status shall be displayed by indicating lights on the front panel. The controller shall be insensitive to phase angle shifts and be capable of operating with input line voltage of 95 to 130 volts AC without affecting accuracy. Conductivity level shall be recorded on an indicating meter. The chemical feed shall be controlled by a reset timer actuated by a make-up water meter with electric contractor. The chemical feed control module shall have a pump status indicating lamp, a Manual-Off-Auto switch and a 20 amp pump relay. 2. The chemical feed pumps shall be mounted in a NEMA 1 steel enclosure, primed and fully painted. They shall be pre-plumbed, pre-wired and include the following: a. Sample stream piping assembly, including a conductivity flotee, sample cock, check valve and three chemical injection tees. b. One Inhibitor feed pump, two biocide feed pumps of the positive displacement type, with ball type check valves, 120/1/60 fractional hp motor drive, discharge pressure relief valve, foot valve, suction tubing and discharge tubing. The feed rate shall be adjustable while the pump is running and the chemicals shall be pumped directly from the shipping container. Pump shall be U.L. Listed and shall be manufactured by PULSA FEEDER, LMI or CHEM-TECH. 3. One sample stream injection assembly. 4. One water meter, complete with electric contacting registers sized to meter the peak make-up rates. 5. One bleedoff solenoid and throttling valve, sized for bleed off requirements of the system. 6. One 50-gallon inhibitor tank and two 30-gallon biocide tanks. Tanks shall be polyethylene and shall include lids. Pump suction will be through the lid. Fittings in tanks are not allowed. E. Hot and Chilled Water Systems - Contractor shall install a One Shot Feeder for each system, minimum four quart capacity, designed to meet pressure requirements of the specific system /13

4 PART 3 - EXECUTION 3.01 INSTALLATION The water treatment system shall be installed as recommended by the manufacturer. A. Pre-Cleaning and Cleaning 1. Provide the chemicals used for the pre-cleaning and cleaning sequences listed in Section Chemicals shall be capable of removing deposits from construction, such as pipe dope, oils, most loose mill scale, and other extraneous materials. The products used shall inhibit corrosion of the various metals in the piping systems and shall be safe to handle and use. Effectiveness of the product shall be such that the water need only be at ambient temperatures. Add recommended dosages of products for corresponding system capacities. B. ph Balance and Treatment 1. Piping systems shall be drained and flushed until the total alkalinity of the rinse water is equal to the makeup water, as described in Section Refill with clean water, which shall be properly treated to prevent scale and corrosion during operation of the water systems (See paragraph 3.01.C). This contractor shall assist in performing the ph balance of the systems. C. Maintain the following conditions in each system: 1. Chilled 2. Hot a. ph 7.0 to 9.0 b. Buffered Nitrite 500 PPM a. ph 7.0 to 9.0 b. Buffered Nitrite 1000 PPM to 180 Deg. F 2000 PPM above 180 Deg. F 3. Condenser a. ph 7.0 to 8.0 b. Organic Inhibitor 15 to 25 PPM c. Cycles 7 Maximum d. Organic Growths None /13

5 3.02 SYSTEM SERVICE A. The water treatment service shall start after the initial cleaning, flushing, start-up and check out of the water systems and shall continue for a period of one year after the substantial completion date of the entire project. B. Prior to the substantial completion date and during the one year service period after this date, the water treatment contractor shall visit the site and thoroughly inspect the systems for proper operation, make necessary adjustments, test water and chemical conditions, and complete a written report on conditions. Service frequency shall be as a minimum as follows: 1. Chiller/cooling tower condensers - every two weeks 2. Closed loop hot and chilled water - once per month C. Prior to the substantial completion date and during the one year service period after this date, the water treatment contractor shall test water samples from cooling tower water for legionella pneumophila. Tests shall be made monthly when the cooling tower operates. The report shall give the result in bacteria per millimeter and include the result from the previous month. D. The water treatment contractor shall maintain complete records of the treatment program for each system and submit to the Owner three copies of each report distributed to: 1. System Site 2. Project Manager, Office of Design and Construction Services, 8115 Gatehouse Road Falls Church VA Coordinator, Mechanical Maintenance Division, Maintenance Services, 5025 Sideburn Road, Fairfax Virginia E. The initial fill of water treatment chemicals and water treatment service shall be witnessed and verified by the Owners representative. A signed service card must be obtained by the technician after each visit for service. END OF SECTION /13