COOLING SYSTEMS WATER TREATMENT TRAINING Presented by A

COOLING SYSTEMS WATER TREATMENT TRAINING Presented by A and W TECHNOLOGIES

Plant Refrigeration Costs Electricity 20% 59% Equipment Depreciation Labor Makeup Cost 13% 2% 5% 1% Sewer Cost Water Treatment

NUMBER 1 PRIORITY SAFETY THINK

COOLING WATER IMPURITIES n TYPICAL IMPURITIES – Ions Calcium, Magnesium, Sulfate, Silica, chlorides All can react to form harmful deposits – p. H Increasing p. H - increased scale potential Decreasing p. H - increased corrosion potential

COOLING WATER IMPURITIES n Characteristics – – – – p. H M alkalinity Chorides Hardness Silica Iron Conductivity Copper City Water Well 7. 2 0 ppm 12 ppm 17 ppm 4. 2 ppm. 05 to. 5 ppm 60 mmhos. 1 ppm 7. 3 71 2. 3 68 23. 5 160 - 185. 1

FORCED DRAFT TOWER Condenser Water HOT WELL EVAPORATION FAN Fill Solenoid valve Blowdown line to drain MAKEUP water meter WELL & CITY 3 Chillers COLD WELL Recirculation pumps

A and W Forced Draft Tower TECHNOLOGIES Blowdown MAKEUP Water Meter PROCESS 74*F 90*F

NATURAL DRAFT TOWER 500’ 500, 000 GPM 10* F Delta T - Approach Power Generating Station

Evaporative Condensor Water distribution porat Eva Chillwater in the tubes or ammonia ? Makeup water To chemical feed center Recirculation pump • BAC Evaporative condensor Chicken plants and food manufacturers Hey what the heck is that?

COOLING WATER n OPERATIONAL FACTORS – Evaporation = (Recirc. Rate x Delta T x. 001) = GPM Pure water leaves Solids concentrate Requires fresh water makeup to be added – Blowdown Equal to Evaporation Cycles - 1 – Cycles Equal to Conductivity in Tower Conductivity in Makeup *Makeup = Evap + BD

Typical Specifications n Evaporation » 5000 x 10 x 70% x 24 x. 06 = 50, 400 GPD n Blowdown » 50, 400 / 5 -1 = 12, 600 GPD n Makeup = Evap + BD » 50, 400 + 12, 600= 63, 000 GPD

Typical Specifications n Evaporation Credits » 4220 x 10 x 60% x 24 x. 06 = 36, 461 GPD n At 365 days per year this is 13, 308, 265 GPY n Sewer charge is $2. 75 per 1000 gallons n 13, 308, 265/1000 = 13, 308 x $2. 75 = $36, 597

Optimizing Cycles 40 Tower Blowdown 35 30 25 20 15 10 5 0 1 2 3 Cycles 4 5 6 7

Saves Water 40 Tower Blowdown 35 30 25 20 15 10 5 0 1 2 3 Cycles 4 5 6 7

COOLING WATER PROBLEMS n CORROSION – Tendency for metal to revert to its natural state – Electrochemical reaction – Anode, cathode, source of electron flow and an electrolyte – General thinning and/or pitting – Galvanic corrosion

At the Anode u. One end of the “battery” Fe++ Anode e- e- e. Fe = Fe++ + 2 e-

At the Cathode u. The other end completes the circuit! OHe 1/ O 2 2 e- e- + H 2 O + 2 e- H 2 O Cathode = 2 OH- O 2

Corrosion Products Form Result: OHFe++ Fe(OH)2 Anode OHCathode Fe++ + 2 OH- = Fe(OH)2

COOLING WATER TREATMENT n CORROSION CONTROL – Without it. . Destruction of equipment Plant downtime due to equipment failure Decreased efficiency / decreased heat transfer

COOLING WATER TREATMENT n CORROSION CONTROL – Anodic inhibitors – Cathodic inhibitors Continuous feed must be maintained to keep the protective film in place !! Control of blowdown / p. H critical to success!!

A and W Cooling Products

A and W Technologies Three-Part Corrosion Protection n Deposit Protection n Molybdate Tracer n Medium to High p. H n

A and W Inhibitors. . . ÊPassivates Anodic Sites A and W ËProtects Cathodic Sites To Protect and to Serve ÌShields Copper Surfaces 4 Reliable Corrosion Protection

1. Anodic Protection O 2 ------------ -iron oxide-----------e- e- A and W Inhibitors Passivate the Steel

With A and W. . .

COOLING WATER PROBLEMS n SCALE – Crystalline structure – Combinations of cations and anions – Water analysis can provide scaling indices to determine scale forming potential – Inversely soluble » As temperature increases solubility decreases (scale can come out of solution)

COOLING WATER PROBLEMS n FOULING – Accumulation of organic / inorganic material – Examples: Biological slimes Algae Corrosion products Airborne dirt and debris – Subject to flow velocities – Organic fouling can be found throughout

A and W Inhibitors. . . Technology Suspends Contaminants

A and W Inhibitors. . . Patented Technology Suspends Contaminants Inhibits Scale Formation

A and W Inhibitors. . . Patented Technology Suspends Contaminants Inhibits Scale Formation Allows High Cycles

A and W Inhibitors. . . Patented Technology Suspends Contaminants Inhibits Scale Formation Allows High Cycles Maintains Heat Transfer Efficiency

CHEMICAL FEED CONDENSER WATER A and W TECHNOLOGIES All pumps plug into controller. Blowdown solenoid also plugs into controller. Signal from water meter back to controller if used. Power needs to be supplied to the controller. 110 VAC @ 10 amps. 3/4 INCH SCH. 80 PVC Return to Tower USE SCREWED TEES AT INJECTIONS Supply line CONTROLLER A and W CORROSION COUPON RACK 3/4 inch PVC pipe and screwed tees. Notice orientation, with flow. Can be constructed on site. *Presently No Coupon Studies! AWC Awc 310 AWC M-1015 AWC M-1202 AWC CL-1 & M 92

COOLING WATER TREATMENT n BIOLOGICAL CONTROL Cooling water systems provide an excellent environment for microbio activity Fouling and underdeposit corrosion Toxicant evaluations can determine the most effective biocide ALGAE BUGS

COOLING WATER TREATMENT n BIOLOGICAL CONTROL – Oxidizing biocides “BURNS THE BUGS” Chlorine, bromine, sodium hypochlorite Provides quick kill Fed at a rate exceeding the chlorine demand plus 0. 5 to 1 ppm free chlorine residual for one to four hours

COOLING WATER TREATMENT n BIOLOGICAL CONTROL – Nonoxidizing biocides – “POISONS OR STARVES ‘EM” Used where chlorine demand is high or. . . Supplemental biocide for chlorine Remain in the system longer than oxidizing biocides Provides longer contact time for kill

TESTING AND CONTROL n SYSTEM TESTS – Conductivity (All systems) – p. H (City, Tower, All closed loops) – Molybdenum (Tower, All closed loops) – Cycles (Tower) – Microbiological (Tower) Data should be entered in log book or monitored with computer trending

TROUBLESHOOTING Low levels n Algae in tower n Tower losing water n Closed loops losing water n High head pressure on chillers n Leaks on chemcials n Bugs in Chillwater n

Cooling Service Program Lab Analysis – Water – Deposit – Metallurgical Test HX Equipment Corrosion studies Chiller efficiency studies Micro-biological studies Cooling tower wood analysis LSI Calculations Quality Assurance

AT&T A and W Technologies Thank you for the opportunity