China's oil refineries and chemical plants that use petroleum distillates as raw materials mostly use oil-based alkali refining processes. The production process will discharge a large amount of alkaline waste liquids containing high pollutants, and their COD, sulfide, phenol and other pollutants account for emissions. Emissions from oil refineries or petrochemicals account for 20% to 30% of the total emissions of pollutants from refineries and petrochemical companies. To this end, Sinopec has listed the treatment of spent lye as a key project for environmental protection. The above two units have jointly developed refinery alkali residue and wastewater treatment technologies.
The technology adopts the “modulating wet oxidation deodorization+batch activated sludge process†technology to solve the engineering and technical difficulties of mitigating the structure of the wet oxidation reactor, cooling the gas-liquid mixture after deodorization, and the structure of the SBR bioreactor. Researchers developed five proprietary equipment and process technologies such as internal-circulation wet-oxidation reactor, gas-liquid mixture separation after deodorization, cooling, and tail gas purification and cooling tower, and obtained two patents for waste alkali treatment.
Industrial test results show that the use of this technology can reduce the content of sulfide in waste lye from 8g/L to 0.5mg/L, phenol from 10g/L to 2mg/L and COD from 150g/L to 500mg. Below /L, it meets the water quality standards of the refinery wastewater treatment plant; it can completely eliminate the air and water pollution of sodium sulfide and organic sulfides in the refinery waste alkali liquor, and remove more than 90% of COD, phenol, etc. from the waste alkali liquor. Contaminants.
This achievement provides a suitable complete set of technology for the treatment of waste lye in the refinery, greatly reducing the influent load on the sewage treatment plant and ensuring the normal operation of the existing sewerage treatment system and meeting the discharge standards.
The technology has the advantages of simple process flow, small device footprint, low investment and operating costs, high automation level, easy operation, etc. It can replace the imported devices and provide powerful technical support for the expansion and reconstruction of refinery and ethylene plants in China. At present, the results have been successfully applied to more than 10 petrochemical enterprises in Shanghai, Daqing, Qingdao and other places and achieved good results.
Efficient eradication of odor pollution in refinery plants. Self-contained alkali residue wastewater treatment technology has been promoted
The reporter learned from the Fushun Petrochemical Research Institute of Sinopec on June 5 that the refinery alkali residue and wastewater treatment technology jointly developed by the hospital and Shanghai Gaoqiao Branch can effectively oxidize the spent caustic liquid and liquid hydrocarbons. Liquid and other high-concentration wastewater. This technology with independent intellectual property rights has reached the international advanced level and has been successfully used in more than 10 domestic refining and chemical companies.