Siemens helps petrochem projects meet stringent environmental regulations

31-Aug-06

Siemens technology will help petrochemical projects meet Stringent Environmental Discharge, Reuse Regulations. Fujian Refining and Ethylene Joint Venture Project, the largest world-class Chinese project is a joint venture between Fujian Petrochemical Co., Ltd., ExxonMobil and Saudi Aramco. The JV has selected the Water Technologies division of the Siemens Group Industrial Solutions and Services (I&S) to provide equipment for treating ethylene spent caustic and wastewater. The four-part system will help the joint venture meet stringent discharge and reuse regulations. The system comprises of Zimpro wet air oxidation, Pact biological treatment, Zimpro wet air regeneration and Hydro-Clear sand filter systems. The Zimpro wet air oxidation system will help alleviate problems of disposal and odor. The technology destroys odorous sulfides and allows acid neutralization of the spent caustic. It also allows for discharge to biological treatment, in this case, a PACT system followed by sand filtration. The new Pact system will treat combined refinery wastewaters high in TDS and ethylene plant wastewaters. Also to achieve reuse objectives and reduce COD, an activated sludge wastewater system already in use at the plant will be converted into a second Pact system. A new wet air regeneration system is being installed at the plant, which will treat spent carbon and biomass from both Pact systems. Both Pact systems also have effluent quality guarantees. For tertiary treatment following the Pact systems, the Hydro-Clear sand filter uses a shallow, 10-inch bed of 0.45 mm sand and a pulsed bed to help achieve low effluent CODs. Effluent from the new wastewater treatment plant will contain <100 mg/L COD, and will be discharged to the ocean. A <30 mg/L effluent COD from the existing wastewater treatment plant will be reused for cooling tower makeup water.