A Zimpro wet air oxidation (WAO) system supplied by Siemens Water Technologies will treat ethylene spent caustic at a grassroots ethylene production plant in Ras Laffan Industrial City, Qatar. Part of a joint venture agreement between Q-CHEM-II, Qatofin and QP, the Ras Laffan Olefins Company Ltd (RLOC) plant will be one of the world's largest plants for this industry once it is commissioned in 2008.
Qatar is home to one of the world's largest natural gas reserves, and considerable government resources have been invested in the development of facilities to process and export products like ethylene. Using WAO technology will help the plant alleviate two problems frequently associated with ethylene spent caustic: disposal and odor. The technology destroys odorous sulfides, and allows acid neutralization of the spent caustic and discharge to conventional biological treatment.
"There is a tremendous amount of growth in Qatar associated with the oil and gas industry," says Rob Lawson, director of industrial sales for Siemens Water Technologies, in Rothschild, Wisconsin. "This will be our third major project in the area using state-of-the-art WAO technology for treating spent caustic. With dozens of operating units treating ethylene and refinery spent caustic worldwide, our experience with these types of applications will allow the facility to produce ethylene without having the additional expense of spent caustic disposal."
The ethylene plant will have the capacity to produce 1.3 million metric tons of ethylene per year. The produced ethylene will travel along a 120 km pipeline from Ras Laffan to Mesaieed, where derivatives polyethylene plants will be located within the existing facilities of Q-CHEM and QAPCO. Q-CHEM's facility has been using Zimpro WAO for spent caustic treatment since 2002.
In addition, in fiscal year 2005 Siemens Power Generation secured the order from JGC Corporation of Japan for three SST-400 back pressure steam turbines each with an output of 32 MW on behalf of Dolphin Energy Ltd. of the United Arab Emirates. The turbines will be used to generate power for the Ras Laffan plant, and the excess steam will be used in the gas separation plant, which processes liquid hydrocarbon products, such as condensates (gaseous oil) and liquefied gases. The remaining natural gas is then treated for use in driving the compressors and transported by pipeline to the United Arab Emirates.