Shell International Gas Ltd. recently debottlenecked its gas-to-liquids plant in Bintulu, Malaysia, increasing production of the feedstock it uses to make GTL base stocks.
The 10-year-old plant, the worlds second-largest natural gas-to-liquids refinery, had daily capacity to make 12,500 barrels of oil products – approximately 10 percent being a waxy raffinate used as feedstock for high-quality base stocks. The debottlenecking, completed in May, increased capacity by 20 percent, according to William King, base oils manager for Shell Middle Distillate Synthesis, the technology used at the plant. King said production of waxy raffinate has increased by approximately the same proportion.
Gas-to-liquids technology has been promoted for years as a means to turn stranded natural gas reserves into high-quality and ultra-clean fuels and other oil products. GTL base oils are said to perform on par with polyalphaolefins while costing less to make.
The Bintulu plant is the only existing GTL plant producing a lube feedstock. PetroSAs larger, 30,000 b/d plant at Mosselbay, South Africa, makes fuels and petrochemical feedstocks.
Many market observers predict that large-scale plants will be built within the next few years to meet requirements for cleaner diesel fuel. Shell and several other oil companies have announced plans for big plants, but only ExxonMobils Qatar project has specified plans to produce base oil feedstock. Syntroleum Corp., of Tulsa, Okla., had obtained permits to build a GTL specialties plant with base oil production in Western Australia, but gave up on the project last year for want of financing.
In addition to waxy raffinate, the Bintulu plant makes naphtha used as ethylene feedstock, kerosene, gasoil, linear paraffins, solvents and waxes. The waxy raffinate is transported to other refineries, primarily in Japan and France, where it is further processed into base oil. Shell markets some of the base oil under the Shell XHVI brand name but, according to King, keeps most of it in house for use in premium motor oils.