The Arak Refinery's development plan is now 57 percent complete and is supposed to boost the refining capacity of the facility to some 250,000 barrels per day from the current 169,000 bpd, SHANA news agency reported on Sunday.
The development plan would cost around 2.5 billion euro, the report added.
Once the project comes on stream, the refinery's gasoline production capacity will also rise to 16 million liters per day from the current figure of 4.7 million liters.
The second phase of the refinery is projected to produce 1.1 million liters of propylene. The produced propylene will be fed to petrochemical complexes.
According to the project manager Rashid Seyyedian, the National Iranian Oil Engineering and Construction Company is the proprietor and a consortium comprised of some Iranian firms and a Chinese company is the major contractor of the project.
Domestic contractors hold 70 percent which the Chinese share is 30 percent of the $2.5 billion project.
The Arak Refinery has gone through a major development plan to increase its share of national gasoline production to 44 percent.
The Engineering, Procurement and Construction (EPC) contract of refinery development plan was signed in August 2006 and the refinery is supposed to come on-stream in July, 2010.
The refinery came on stream in 1993 with the nominal capacity of 150,000 barrels per day. Currently, the refinery produces some 170,000 barrels of light crude oil, liquefied gas, propylene, gasoline, high-octane gasoline, diesel oil, kerosene, furnace oil, and sulfur.