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Oil Business

Toa Oil has been entrusted with oil refining by Idemitsu Kosan Co., Ltd. The crude oil processing capacity is 70,000 barrels per day, but the refinery has the highest cracking unit installation rate in Japan, and it operates efficiently by processing raw oil received from outside in addition to crude oil.

1. Receiving crude oil and feedstock: 
   
   The crude oil imported by Idemitsu Kosan and transported by supertanker is transferred from the loading facility (SBM) installed in Tokyo Bay to the crude oil storage tanks on Higashi-Ogishima Island, from where it is supplied to the refinery. In addition to crude oil, heavy feedstock oil that cannot be processed at other refineries is also received by ship or through pipelines from nearby refineries.
    
2. Petroleum Refining

   1. Distillation
      
      Crude oil is separated into gasoline, kerosene, diesel, and heavy oil using a distillation unit. The process of separating oil by taking advantage of the difference in boiling points is called "distillation" and is the basic process of oil refining. Two types of distillation are carried out: normal pressure distillation, which is carried out under conditions close to atmospheric pressure, and reduced pressure distillation, which is carried out under conditions close to a vacuum.

   2. Reforming

      The gasoline obtained by distillation is reformed in a reformer to produce gasoline with a high octane rating. The octane rating is a unit that indicates the anti-knock properties of gasoline (how difficult it is to cause abnormal combustion), and is a process that improves the performance of gasoline.

   3. Oil Refining - Cracking

      The heavy oil obtained by distillation is cracked in a cracking unit into gasoline, kerosene, diesel, etc. This is a process to convert low-value added heavy oil into high-value added petroleum products, and two types of cracking are carried out: catalytic cracking and thermal cracking.

   4. Desulfurization

      Gasoline, kerosene, diesel, etc. obtained through distillation and cracking are desulfurized in a desulfurization unit. Desulfurization is a process that removes sulfur, which causes environmental pollution, and by using hydrogen and catalysts at high temperature and pressure, we produce environmentally friendly petroleum products that meet high quality standards.

3. Shipping

   The petroleum products we produce are shipped day and night without interruption under strict quality control.
   They are transported by tanker truck to nearby service stations and inland oil tanks, and by ship to distant oil tanks

Refinery Configuration

Key Observations

• The Flexicoker (重質油熱分解装置, 27,000 B/D) receives feed from two sources: the Vacuum Distillation Unit (vacuum residue) and a separate 原料油 (Raw Material / Feed Oil) stream — consistent with the Toa Oil presentation's description of inter-site feed integration between the Ohgimachi and Mizue plant areas

• The golden/amber arrows from the Flexicoker route to the Mizue Power Plant (水江発電所), confirming the 50% Flexigas-to-power-plant utilization described in the Toa Oil presentation

• FCC bottoms/slurry also route to the Power Plant via the same amber flow path

• The VGO HDS → FCC route (46,000 B/D → 42,000 B/D) confirms hydrotreated heavy gas oil from the Flexicoker is used as FCC feed, as described in the yield table

Overview of Keihin Refinery

The Keihin Refinery is located in the center of the Keihin coastal area, one of Japan's leading industrial regions, and functions as a refinery that plays a part in ensuring a stable energy supply for the Idemitsu Kosan Group. The Keihin Refinery is characterized by its high rate of cracking units, and in addition to the crude oil that general refineries process, it also processes heavy feedstock oil (residual oil generated after processing crude oil) received from other refineries.

The processing capacities* of our major equipment are as follows:

Mizue Power Plant (power generation facility)

Taking advantage of the deregulation of the electricity market, we have participated in the electricity supply business that makes effective use of fuel produced as a by-product at existing oil refineries, and have been operating the Mizue Power Plant since 2003. The plant also plays a role in supplying electricity and process steam to our Keihin Refinery.

The processing capacities of the main equipment at Mizue Power Station are as follows: