| To solve the problem of water resources shortage faced by the oil refinery enterprises and to reduce the environmental pollution caused by the discharged sewage from them at the same time, a research of advanced wastewater treatment process was carried out in lab-scale and trial-scale. The aim of the research was to develop an innovative advanced treatment process based on the core technique of ozone-bio-carbon treatment for the refinery sewage. This technique took the secondary effluent of oil refinery attained the national discharge standards as the test wastewater and made it to meet the quality demand of supplementary water for the industrial circular cooling water and boiler water. The routine wastewater quality analysis showed that the main pollutants in the oil refinery effluent were COD, ammonia nitrogen and mineral oil, and the CG/MS analysis found 11 organic components, mainly hydrocarbons. From the above preliminary analyses it was determined that the advanced treatment process should include flocculation, aeration or advanced oxidation, biochemical process, activated carbon adsorption process and etc., and be researched by lab-scale test. The result of ozone/ultrasonic treatment of oil refinery wastewater in the lab-scale test showed that ozonization could reduce the COD content in the oil refinery wastewater and the degradation rate was in direct proportion to the quantity of ozone added and the treatment time, and ultrasonic played an auxiliary part to promote the reaction in the process.The lab-scale advanced treatment test of refinery sewage with three kind of filters, two kind of nitrification de-ammonia microbes and one kind of small-sized filter showed that the bio-filter system could fulfill the aim of deep nitrification of the oil refinery sewage. Activated carbon was selected as the best bio-filter in the bio-filter system, nitrification sphaericus as the best microbe which could reduce ammonia nitrogen content of the oil refinery sewage from 40mg/l to below 4mg/l at 30℃ in a duration time of 0.83h to meet the water quality demand of circular cooling water.The adsorption denitrification lab-scale test of oil refinery sewage with zeolite, wollastonite and resin showed that the denitrification efficiency of zeolite was 4.28mg/g and resin 5.49mg/g, which meant that the efficiency and economics were relatively poor than bio-carbon tower. The fine filtration lab-scale test indicated that ultrafiltration and nanofiltration equipments had high removal efficiency for suspended substances, reached more than 90%, but no removal effect to ammonia nitrogen in general.The trial-scale test was designed and arranged on the basis of lab-scale test, the test procedure was as follows: the discharge standard attained wastewater first entered into the units for flocculation, aeration and sand filtration to remove suspended substance and mineral oil, then entered into ozone-bio-carbon tower to remove ammonia and COD biologically. The effluent water could be used as supplementary circular cooling water, then after further treated by fine filtration and resin adsorption used as boiler water. Taking the raw water of oil refinery as water sample two trial-scale tests were carried out with hydraulic load of 0.2m3/h and 0.5m3/h separately. The tests showed that the contents of COD, ammonia nitrogen, mineral oil, suspended substance and volatile phenols were lowered from 44.07 to 102.13mg/l, 28.37 to 50.01 mg/l, 4.68 to 19.36 mg/l, 7.2 to 34.5 mg/l and 0.14 to 0.31 mg/l respectively and the corresponding removal rates were 94%, 96.1%, 91.9%, 98.2%, 100% respectively, all of which met the supplementary circular cooling water standards. A 5.5h anti-impinge test indicated that the whole technical process had a better anti-impinge ability The feasibility modeling test of water quality showed that the quality of reclaimed water after the treatment by the above process, when used as supplementary circular cooling water and boiler water, met the nation standards in the respect of corrosion, scaliness and bac...
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