As the Idemitsu Kosan Group's core refinery, the Keihin Refinery plays a crucial role in supplying energy to greater Tokyo and all of Eastern Japan, a major oil-consuming region.
1Receiving of crude oil
Crude oil imported by Idemitsu Kosan and transported on supertankers is transferred from landing facilities (SBM) on Tokyo Bay to crude-oil storage tanks at Higashiogishima, and from there to refining facilities.
2-1Oil refining: Distillation
Distillation unit is used to separate crude oil into gasoline, kerosene, diesel oil and heavy oil. The use of differences in boiling points to separate grades of oil is called “distillation” and is a basic process of oil refining. There are two types of distillation: atmospheric distillation and vacuum distillation.
2-2Oil refining: Reforming
Gasoline obtained from distillation is sent to catalytic reformer to produce high-octane gasoline. The octane value of a gasoline is a unit that indicates its anti-knock performance (resistance to abnormal combustion). Increasing the octane value of gasoline increases the gasoline’s performance.
2-3Oil refining: Cracking
Heavy oil is sent to cracking units to break it into light fractions such as gasoline, kerosene, diesel oil and process gases. This process converts low-value heavy oil into petroleum products of higher value. There are two types of cracking units: Fluidized Catalytic Cracker and Flexicoker.
2-4Oil refining: Desulfurization
The gasoline, kerosene, diesel oil obtained by distillation and cracking are treated for removing contained sulfur in Desulfurization units. Desulfurization is a catalytic chemical hydrogenation process. Reaction takes place at elevated temperature and pressure in which the organic sulfur species are converted to hydrogen sulfide.
The petroleum products thus produced are shipped under strict quality control, 24 hours a day, 365 days a year.
At suburban service stations and inland oil terminals, the petroleum products arrive by tank lorry. Tanker ships serve more distant oil terminals.