NEW WASTE-HEAT REFRIGERATION UNIT CUTS FLARING, REDUCES POLLUTION

Abstract

Planetec Utility Services Co. Inc. and Energy Concepts Co. (ECC), with the help of the US Department of Energy (DOE), developed and commissioned a unique waste-heat powered LPG recovery plant in August 1997 at the 30,000 b/d Denver refinery, operated by Ultramar Diamond Shamrock (UDS). This new environmentally friendly technology reduces flare emissions and the loss of salable liquid-petroleum products to the fuel-gas system. The waste heat ammonia absorption refrigeration plant (Whaarp) is the first technology of its kind to use low-temperature waste heat (295 F) to achieve sub-zero refrigeration temperatures ({minus}40 F) with the capability of dual temperature loads in a refinery setting. The ammonia absorption refrigeration is applied to the refinery`s fuel-gas makeup streams to condense over 180 b/d of salable liquid hydrocarbon products. The recovered liquid, about 64,000 bbl/year of LPG and gasoline, increases annual refinery profits by nearly $1 million, while substantially reducing air pollution emissions from the refinery`s flare.