The Study Of The Treatment For Oily Sludge By Extraction

Oily sludge, a solid waste come from the oil-field production process, was listed in the catalogue of national dangerous waste. The harmless treatment for the oily sludge is still a difficult work in the world. The mechanical and biological methods have been reported to oily sludge in the Shengli Oilfield, but the treatment result can' t reach the national emission control criterion at present.This thesis introduced the purport for treating oily sludge, and summarized the disposal techniques and progresses in the world. A new extractive method, three phases (oil -water -solid) extraction, is adopted in this research. It is demonstrated that this method is economical, environmental, and high efficient. Two kinds of oily sludge, including high oil content (32.73%) and low oil content (9.95%), were chosen in this study. And the temperature range was selected from 30℃ to 40℃. The technique conditions (including the extraction time, parallel, the emulsification status control), and basic parameters (including the saturated concentration , distributive ratio, and extraction efficiency) were confirmed by the experiments. According to the experimental results, mathematics model was established in order to provide a viable project for the oily sludge treatment in the Shengli Oilfield.The experimental result shows that the optimal condition for the extraction technique is: the volume ratio (between oily waste water and extractant) 1. 5 ~2; the stirring speed 180r/min; the oscillating speed 110r/min. At 30℃ ~40℃, distributive ratios are constant, and all the basic parameters are mainly influenced by extractant qualities and oil content. According to the result of simulated experiment, the oil content of oily sludge may be under 1% after the extraction treatment in the optimal condition. Comparing the results between mathematics model calculation and actual experiment, we can find that the difference for the two results is small and influenced by the oil content and the reaction order of countercurrent.