Forced Draft Tower A and W TECHNOLOGIES MAKEUP Water Meter PROCESS 74*F90*F Blowdown
NATURAL DRAFT TOWER 500’ 500,000 GPM 10* F Delta T - Approach Power Generating Station
Evaporative Condensor Makeup water To chemical feed center Chillwater in the tubes or ammonia Water distribution Hey what the heck is that? ? Evaporation Recirculation pump BAC Evaporative condensor Chicken plants and food manufacturers
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*Makeup = Equal to Evaporation Evap + BD Cycles - 1 Cycles - 1 –Cycles Equal to Conductivity in Tower Equal to Conductivity in Tower Conductivity in Makeup Conductivity in Makeup
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
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
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 / pH critical to success!!
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 Biological slimesAlgae Corrosion products Airborne dirt and debris 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
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 A and W Inhibitors...
CHEMICAL FEED CONDENSER WATER CONTROLLER A and W 3/4 INCH SCH. 80 PVC USE SCREWED TEES AT INJECTIONS Supply line Return to Tower CORROSION COUPON RACK 3/4 inch PVC pipe and screwed tees. Notice orientation, with flow. Can be constructed on site. *Presently No Coupon Studies! 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. 110VAC @ 10 amps. Awc 310 M-1015 M-1202 CL-1 & M92 AWC A and W TECHNOLOGIES AWC
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 BUGS ALGAE
COOLING WATER TREATMENT n BIOLOGICAL CONTROL –Oxidizing biocides - “BURNS THE BUGS” Chlorine, bromine, sodium hypochlorite 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... 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) –pH (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 n 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
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
A and W Technologies Thank you for the opportunity AT&T