Used 350,000 TYP Ethylene Plant built in 1969. Designed to produce ethylene and propylene from naphtha and gas oil. The plant is still in operation. Major equipment had upgrade in recent years. For example, a new steam cracking furnace was installed in 2000 and is capable to process 40 tons/hr. New compressors and turbines were installed in 2000. Caustic soda of 15 % is used to eliminate sour gases contained in the naphtha feed. The naphtha / ethane furnace has 84% energy efficiency, naphtha / C4 furnace 84% - 90%, ethane furnace 90%, naphtha furnace 90%. Product ethylene is compressed at 17.5 tons/hr with suction pressure at 17 bar and discharge pressure of 80 – 97 bar. The compression is in 2 steps with cooling of every stage’s outlet. The unit is controlled through a "digital system of control command". The digital regulation is configured and programmed for the specific applications.