A project to recover valuable products from refinery off-gases emitted in the process of gasoline production is being implemented at the Isfahan Oil Refining Company in the namesake province, the project manager said.
“The initiative is expected to become operational in 2022 and help recover hydrogen and other hydrocarbons like liquefied petroleum gas in the refining facility,” Omid Aqababaei was also quoted as saying by IRNA.
Hydrogen is an important and expensive commodity produced during oil refining and petrochemical processing and it is required for many operations such as hydro-treating where it is used to remove impurities such as sulfur from streams and to hydrogenate aromatics, olefins and hydrocracking where it breaks down large hydrocarbons into smaller, higher value molecules.
“Membrane and pressure swing adsorption units have been installed to recover hydrogen from the various waste gases in the refinery,” he added.
Some 66% of world production of hydrogen, estimated at 70 million tons, are used as feedstock in oil refining, ammonia production, methanol and, in recent years, in the development of engines that run on hydrogen.
As refinery product specifications become stricter to meet environmental requirements, demand for hydrogen from the refinery has continuously increased to supply hydro-processing units.
Global economic trends toward the use of heavier crudes result in a higher need for hydro-processing and thus a higher need for hydrogen.
Euro-5 Diesel
The company now produces 4 million liters of diesel per day in compliance with Euro-5 emission standards and output will rise fivefold, Morteza Ebrahimi, the head of the refinery, added.
According to the official, IORC launched a sulfur granulation unit with a daily capacity of 300 tons in 2020, which was in line with policies to reduce environmental pollution and upgrade the quality of refined products.
Both plans are aimed at minimizing the environmental impact of sulfur and curbing emissions.
Sulfur is used mainly to produce sulfuric acid, an important chemical widely used in the fertilizer, rubber, steel manufacturing and pharmaceutical industries.
Established in 1979, the refinery produces 25% of the country’s petroleum products, including 16 million liters of Euro-4 diesel, 8 million liters of Euro-4 and 12 million liters of Euro-5 gasoline per day.
The company has succeeded in removing aromatic compounds, sulfur and benzene from AW-406 solvent and converting it to ++AW-406 solvent.
Isfahan’s refinery is the main supplier of feedstock to Sepahan Oil Company, Isfahan Petrochemical Plant, Arak Petrochemical Plant, Jey Oil Refining Company and Iran Chemical Industries Company.
Crude oil needed by the refinery comes from Maroun Oilfield in Khuzestan Province via a 430-km pipeline.
As per its environmental commitments, the company is making efforts to reduce the amount of sulfur in mazut and gradually reduce the production of this eco-unfriendly fuel by converting it to other products.
Mazut is a highly polluting and low quality fuel used in power plants and factories. The main type of bunker oil for ships is heavy mazut, derived as a residue from crude oil distillation.
Wastewater Treatment
According to Ebrahimi, the company's wastewater treatment unit has been launched to help meet the refinery’s water requirements.
"The plant, with a capacity of 750 cubic meters per hour and costing $8 million, was built in two years," he said.
“The refinery buys the municipal wastewater from towns like Shahin-Shahr in the vicinity of the company, which is piped to the refinery and reused after treatment in the new plant.”
Ebrahimi had earlier warned that the refinery would have to either reduce or stop production, if the worsening water crisis at the refinery was not resolved. The huge refinery consumes 1,000 cubic meters of water per hour, of which 700 cm are recycled and reused.
"We have been grappling with water scarcity for a long time," he said, adding that the company processes 375,000 barrels of crude per day but this cannot be sustained for long.
Located in an arid region with minimal precipitation, Isfahan Province has been struggling with drought for seven years.
According to Mohsen Mehralizadeh, governor general of the province, water flow into Zayandehroud Dam was 1.2 billion cubic meters in 2017, which has now declined to 400 million cubic meters.
"Of the total flow, 320 mcm are used for drinking purposes and the rest for industries," he said, noting that due to the dramatic decline in precipitation, industries have to reduce water consumption by at least 25%.
