Alamo City honors POCL as Top Watersaver

P&O Cold Logistics (POCL) in San Antonio TX recently received the 2002 Top Watersaver Award from the San Antonio Water System (SAWS). POCL/San Antonio has more than 9.5 million cubic feet of storage space kept at -10° to 0°F.

San Antonio first installed a RO (reverse osmosis) system in 1994 as an alternative to chemicals. “Feeding this type of water to condensers,” said Randy Benish, POCL general manager, “had never been tried before. But to remove the calcium from the water before entering the cooling towers seemed to be a good idea. No calcium in the water meant no scale buildup. Also, with no controllers necessary to control the chemical feed and no water bleed off valves to worry about, the maintenance costs reduced dramatically as the efficiency of the refrigeration system improved.”

The drawback was the wastewater the RO system generated. As POCL grew larger, so did the waste. The IR maintenance department developed a process of reusing this wastewater in a new double-pass system, which included installation of water softeners. Their wastewater dropped to an average of 15% versus 50% with the old single-pass system. That works out to more than eight cycles on the water, compared with three to four cycles with chemicals being used at other plants. POCL's use of salt to soften the water is running at 25% of the price it would be paying for chemicals to treat the same amount of water.