| In this paper,current advance of study on the treatment of super viscous oil wastewater was analysed.Based on the characters of wastewater in Liaohe oilfield, having a lot of non-degradable substances,bad biodegradability,great variety of the water quality and discharging standard,the experimental process is drew up. According to the experiment,the removal rate and changes of bacteria in the different stage was monitored and the capacity of anti-oil in biochemical stage was inspected,the most suitable technological plan and operating parameter were determined.Because the effluent from Liaohe oilfield is similar with the super viscous oil wastewater from Chinese Offshore Oil Refinery in Huizhou,the reference was provided for.the sewage treatment of the project.According to the experimental study on the treatment of super viscous oil wastewater,the main result were achieved:(1) There is local discharge standard about the removal rate of main pollutants in Guangdong Province:oil is 97.5%,chemical oxygen demand is 97.6%Ammonia Nitrogen is 95%.So a complete process which is characteric of having shock resistance of oil,higher efficiency of denitrification,good demulsification efficiency, is required:adjusting tank→oil separation→air flotation→CTR→CAST→advanced biochemical treatment.(2) The composite polymeric coagulants of Chang' an university was used in this experiment.According to orthogonal combination experiment,it was concluded that the best experimental condition of the flocculant was 150mg/L and agitation time was 3min,PAM was 1mL and the optimal settlement time was 15min.From results of lab test,the super viscous oil wastewater of 6 cubic metre can be disposed by coagulant with 18L,and PAM with 12 L.(3) The cycle of CAST is 12 hours,and the aeration time is 11 hours.The sludge loading of BOD is 0.01 to 0.04.It has superior biodegradation of inoganics in heavy oil sewage,when the COD is removed,the denitrifying effect could be improved.It has better suitability for the change of burden,and higher flexibility of operation. The cubage burden of COD in the tank of contacting oxidation is 0.13-0.47 kgCOD/m3·d.There is a lot of biofilm with strong activity in the filler.The tank of contacting oxidation have the ability of stronger treatment.(4)The condition of operation was normal:from physiochemical process to biochemistry process,the chemical oxygen demand was reduced by 57%and 78% respectively.;The removal rates of amino nitrogen were 11%and 60%respectively; the oil was reduced by 73%and 64%respectively.With back flocculation,it is approved that the quality of wastewater reached the emission standard.The operation was impacted:from physiochemical process to biochemistry process,the chemical oxygen demand were reduced by 58%and 95%respectively.; The removal rates of amino nitrogen are 73%and 85%respectively;the oil was reduced by 92%and 78%respectively.The removal percent is on the rise with the prolonging of the reaction time;the oil of viscous oil sewage can be reduced to below 5 mg·L-1,the amino nitrogen can be reduced to below 10 mg·L-1.Using the technology to dispose the viscous oil sewage of oilfield is feasible.(5)The dynamics model of CAST reactor was:v=(S0-Se)/(tX),1/θc=Y*Nrs-Kd when CAST reactor was used to disposal super viscous oil wastewater. Sn=43.07mg/L;Vmax=4.74d-1;Ks=1876.40mg/L;Y=0.157;Kd=0.013。...
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