PART 1 GENERAL 1.1 DESCRIPTION.1 This section includes the supply, delivery and installation, testing and placement into operation of a gas chlorination system, and appurtenances as specified herein and as shown on the drawings..2 Components of the gas chlorination system include, but are not limited to the following: a) Weight scales b) Vacuum regulators c/o built-in automatic switchover and drop leg heater c) d) Chlorinators Chlorine injectors e) Chlorine diffusers f) Chlorine leak detector g) Residual chlorine analyzers h) Wall-mounting brackets, panels and other accessories.3 The chlorination system shall conform to the standards established by the Chlorine Institute 1.2 SUBMITTALS.1 The Contractor shall submit the shop drawings and the information for each component of the chlorination system. Information shall include, but not be limited to the following: a) General layout of the system. b) Detailed layout of each component with anchor bolt locations and dimensions. c) Detailed parts list..2 Submit installation manuals before shipment of any equipment..3 Submit as part of the bound, indexed manual for all equipment, the installation, operation and maintenance 30 days prior to start-up. 1.3 SUPPLIER.1 The complete liquid alum feed system and appurtenances shall be supplied by Wallace & Tiernan or approved alternate. 11/89-1 -
PART 2 PRODUCTS 2.1 GENERAL.1 The gas chlorination system shall be designed to draw the pressurized chlorine gas from ton containers into the clarified water and clearwell effluent noted below: a) No. of systems two (one as standby or trim chlorinator) b) Location chlorine storage room and chlorinator room c) Plant design flow Minimum 2.9 MLD Maximum 8.0 MLD d) Chlorine dose Minimum 1.0 mg/l Average 1.5 mg/l Maximum 4.0 mg/l e) Design temperature 1 to 20 C f) Discharge pressure 50 psi.2 Supply two (2) single ton-container scales, two (2) complete chlorinator systems, two (2) chlorine diffuser, one (1) chlorine leak detector with two (2) probes, three (3) residual chlorine analyzers, and other appurtenances as specified herein and as shown on the drawings. Each chlorinator system shall consist of a vacuum regulator with a built-in automatic switchover and drop leg heater, a vacuum type gas chlorinator and a water operated injector..3 The signals from the filter effluent magnetic flowmeters and chlorine residual analyzer on the filter effluent line will be combined by a PLC built-in program. The resultant 4 to 20 ma output shall be fed to a microprocessor based Signal Conditioning Unit (SCU) controller to proportional control the chlorinators. 2.2 WEIGH SCALES.1 Two (2) weigh scale shall be of the digital readout/electronic load cell type and shall be installed in the Chlorine Storage Room. The scale frame shall have a 2- part epoxy finish and be sized to accommodate 2000 lb ton containers. The scale shall have a size no greater than the dimensions of the ton container it supports and an accuracy of ±1 kg after initial tare weight adjustments..2 Weigh scales shall be complete with a dual channel scale head to provide low weight alarm and to generate a 4-20 ma signal for remote recording of the chlorine usage and trunnions for holding chlorine containers. 11/89-2 -
2.2 CHLORINATORS.1 Two (2) idential chlorinator systems shall be the solution feed, remote vacuum type, wall mounted, V10K gas feed system and shall be as manufactured by Wallace & Tiernan or equivalent. Each system shall be sized to feed 75 lb/d of gas chlorine with a maximum capacity of 200 lb/d. The accuracy of the systems shall be within ± 4% of the indicated feed rate over a feed rage of 10:1 automatic..2 Two (2) ton-container mounted vacuum regulators shall be of the spring-actuated diaphragm type and shall be able to reduce the pressure of the gas without venting and maintain the flow constant for any given setting of the feed rate, regardless of changes in the container pressure. Each regulator shall be complete with a built-in remote vent valve, an automatic switchover, a liquid chlorine drop leg heater, and an separate header valve. The regulators shall also provide signals for local and remote indication of the empty of container. The housing of the vacuum regulators shall be constructed of PVC. The inlet header shall be made of copper and can be mounted on the ton container directly..3 Two (2) identical gas chlorinators will be of the V-notch control type. The gas chlorinators shall consist of a 10 glass rotameter, a direct acting diaphragm type vacuum gauge, V-notch orifice, differential regulating valve, automatic positioner, high/low vacuum alarm switch, and a dedicated signal conditioning unit. All the gas control components shall be constructed of chemical resistant plastics and shall be mounted on the wall mounted panel. The V-notch orifice shall consist of a 3-inch long V-grooved PVC plug which slides in a TFE annular seat. The rotameter tubes shall be constructed of glass and the rotator of approved chlorine resistant material Supply two (2) complete sets of back-up rotameters with different sizes One back-up rotameter shall have the capacity of 10 and another 50 lbs/d. Supply two (2) complete sets of spare parts including V-notch plugs and other accessaries..4 Two (2) identical injector shall receive all chlorine gas and make-up water and shall discharge the resulting solution through ¾ piping to the point of application. Maximum water pressure for the injector is rated 690 kpa. The injectors will be installed in the filter room. 2.3 CHLORINE LEAK DETECTOR.1 One chlorine leak detector shall be supplied and installed in the Chlorination Room. The detector shall be connected to two separate PVC sensing lines, one in 11/89-3 -
Chlorine Storage Room and another in the Chlorinator Room. The unit shall be capable of detecting 1 ppm of chlorine gas in the air and also generating a 4-20 ma output signal proportional to gas concentration for remote indication. The operating range of the unit shall be 0 to 10 ppm..2 The detector shall be wall mounted and operate on 110 volts, 60 Hz, single phase emergency power source. When chlorine is detected, the unit shall activate the alarm in the Chlorine room and Main Control Room. Once activated the alarm system must be manually reset. 2.5 RESIDUAL CHLORINE ANALYZERS.1 Three (3) residual chlorine analyzers shall be of the amphorometric type, and be capable of measuring residual chlorine over a range of 0-3 ppm. Two residual chlorine analyzers will be used to measure the free chlorine and the third one to measure the comboine chlorine. Each analyzer shall be complete with an alphanumeric indicator and access keypad. The indicator shall be supplied with built in components to generate a 4 to 20 ma residual proportional signal for remote recording and chlorinator control..2 The residual chlorine analyzers shall be wall mounted. One free chlorine residual analyzer shall be installed on the filter effluent line and another near the clearwell outlet. The combined chlorine residual analyzer shall be installed on the plant effluent line to water distribution systems..3 Each analyzer shall be complete with test reagents for total chlorine. 2.6 CHLORINE DIFFUSERS.1 Diffuser for adding chlorine solution into Φ400 mm filter influent pipe shall be of rigid PVC pipe injector type. The capacity of this diffuser shall range from 3 kg/d to 30 kg/d. The diffuser shall be complete with a complete set of assembly parts including, but not limited to, corporation cork type main connection, diffuser end plug, and connection pipes..2 Diffuser for adding trim chlorine solution into the clear well shall be of single across-the-channel type and constructed of rigid PVC. The capacity of this diffuser shall range from 0.5 kg/d to 10 kg/d. The diffuser shall be complete with a complete set of assembly parts including, but not limited to, connection flanges, diffuser end plug, and supports recessed in the channel floor. 2.7 PIPING AND FITTINGS.1 Supply all pipes and connections for water supply, gas supply, drains, vents, insect screens and other piping required for the complete installation of the chlorinator systems. 11/89-4 -
.2 All main chlorine gas lines under vacuum and chlorine solution lines shall be schedule 80 PVC and valves 150 lb PVC type except that a 2 meter long flexible polyethylene tubing connection to the individual vacuum regulators..3 Joints shall be socket joints except where flanges are indicated on the drawings. Flanges shall be of the socket type..4 Chlorine solution valve shall be of the diaphragm type, made of polyvinyl chloride material. 2.9 SAFETY EQUIPMENT.1 Emergency Repair Kit One emergency repair kit, Chlorine Institute Emergency Kit "B", for one-ton containers complete with carrying case shall be supplied to the chlorine storage room..2 Personnel Protective Equipment The following shall be supplied within a wall mounted cabinet: a) Complete suit of PVC protective clothing b) One pair of acid resistant gloves c) One pair of protective boots d) Two sets of air masks. PART 3 EXECUTION 3.1 INSTALLATION AND TESTING.1 The chlorinators shall be shop tested before being shipped..2 The installation and testing of the chlorine equipment and accessories and the start-up of the system shall be made under the general supervision of a qualified representative of the equipment manufacturer..3 The manufacturer's representative shall submit (in duplicate) a complete report of this installation and start-up directly to the Engineer. END OF SECTION 11234 11/89-5 -