Study On The Treatment Of Sludge From Petrochemical Industry

Sludge treatment and disposal is an indispensable part for the sewage treatment plants. The aim is minimization, stability, innocuity and resources. It can ensure the normal operation and the treatment effect, and can prenvent secondary pollution.The sludge which expelled from the petrochemical industry sewage structures, is diffcult to sedimentation by nature, because of high water content and fully emulisified. If discharged directly without treatment, not only will cause environmental pollution, but also is an wastement for the crude oil in the sludge.Through analysis the composition and the nature of petrochemical industry "three mud", and combination with the sludge treatment and disposal of domestic and foreign petrochemical industry, and consideration the feature of China's petrochemical industry, this paper studied how to improve the dehydration performance of the sludge systematically by chemical adjustment.In the experiment, chenmical conditioning were conducted for the selective sludge. At the same time, the resistance was measured under the condition of constant pressure, and used the resistance as the evaluation, and select the conditioner which can improve the dehydrated of sludge obviously as the best conditioner. On this basis, the optinal dosage and the operating conditions has been determined. The experiment results showed that PAM+ is the best conditioner, and the best filter is 0.04-0.06MPa; the best pH is range of 6-8, and the best mixing strengthen is between 99.4S-1～22.6S-1 and 198.1S-1～35.5S-1. For the remaining activated sludge, the best dosage of conditioner is 40g/t dry soil, and for the drosses, the best dosage is 50-70g/t dry soil. After the sludge and drosses mixed with different proportion, the best dosage is 50g/t dry soil. Accordance with the character and the resistance of sludge, this study suggests that the oil sludge can be recycling, and the drosses and the remaining mix activated sludge can be treated after mixed.Through the sludge dewatering field test to verify the dehydrated sludge mixed performance, the results showed that used the horizontal screw-type centrifuge, control the speed of centrifuges for 3000 rpm, torque 1.00, dosage 0.5m3/h and the difference was 4.5, after the mixed sludge dewatering, the moisture content of the mud cakes mainly concentrated between 40% and 50%. Selection the horizontal screw-type centrifuge had a better treatment effect for the mixed sludge.