Study On The Evaluation Method Of Oily Wastewater Treatment Agents

In recent years, the use of inorganic flocculants improved the efficiency of natural settlement-coagulation-filtration process, but with the quality of produced water worsensing, the use of inorganic flocculants caused many problems, high dosage of inorganic flocculents, high output of sludge, the mud was difficult to treat, the filter media was blocked, as well as lower-quality oil recovery and other issues, which caused the secondary pollution for the environment. The organic polymer flocculants have received more and more attention with low dosage, fast flocculation and biodegradable, etc.Since the difference of the mechanism of flocculant in inorganic flocculants and organic flocculants, the static evaluation results are always not agree with the practical applications. Therefore studying of organic flocculant performance evaluation methods has the important meaning for the production.This paper analyzed the wastewater quality of the first sewage station in Gudao oil field, simulated oily wastewater, selected the organic flocculants by Graduated cylinder. Organic flocculent was the best reagent. Influencing factors, such as dosage, mixing intensity, intensity time, settling time, pH and temperature, which effect wastewater treatment were researched.The static test method cannot truly reflect the influences of the practical production, so the dynamic test method was proposed. So dynamics evaluated equipment consists of churn-dasher, dosing system and settling tank, was designed. This paper used the equipment simulated the process of dosing, coagulating and settling on line and evaluated the influences of dosage, hydrodynamic condition, settling time and temperature on the wastewater.The static and dynamic test can both reflect the nature quality of flocculant agent. The static test is an intermittent process; the reaction is ideal. The dynamic test results are not as well as the static test results. The dynamic test is a continuous process, which has back mixing, short circuiting and dead position. According to the comparison with static test and dynamic test, there are great differences between two methods in settling time and temperature. So there is certain limitation in the static test, which cannot reflect the influence of hydraulic condition on the treatment results. The dynamic test process and results are close to the actual process and results. So the dynamic evaluation results are more tallies with the actual results.