The Impact Of High Proportion Of Industrial Wastewater On Activity Of Sludge In Orbal Oxidation Ditch And Its Optimizing Control Technology

At present, most enterprises discharge the wastewater into the municipal drainagesystem directly after simple pretreatment in the Three Gorges reservoir area, dealt withthe living wastewater together. The large amount of industrial wastewater into theWWTPs to increase the complexity of WWTPs operational management andmonitoring, leading to accept large industrial district wastewater WWTPs are oftenfaced with the impact of the high proportion of industrial wastewater, because of thecomplexity, diversity and toxic substances of the industrial wastewater. Thisphenomenon is widely existed in the Three Gorges reservoir area. According toactivated sludge system has been impacted by the high proportion of industrialwastewater, leading to activity of sludge decreased and treatment effect dropped. Thethesis surveyed and analyzed the water quantity and quality characteristics of the majorindustrial enterprises in industrial parks to determine the main toxic substances whichimpact WWTPs. By Orbal oxidation ditch pilot plant to research the influence ofactivated sludge system by high proportion of industrial wastewater impacts and theoperation optimization control program which WWTPs suffered the impact of the highproportion of industrial wastewater.According to the terrain and the distribution of drainage network in AirportDevelopment Area, the Area was divided into east and west regions. The high pHalkaline industrial wastewater which discharged by the western major companies is themain reason for the ChengBei WWTP suffered the impact of alkaline industrialwastewater. The low pH acidic industrial wastewater which discharged by the esternmajor companies is the main reason for the ChengBei WWTP suffered the impact ofacidic industrial wastewater. It is surveyed that there are some heavy metal ion such asCu²⁺, Zn²⁺and Ni²⁺in the wastewater of the Area. Considering the toxic effects oftoxicants on activated sludge and experimental conditions, the thesis choose strongalkali, strong acidity and Cu²⁺to simulate a high proportion of industrial waste waterimpact test.pH≤9.5alkaline wastewater impact8h with few influence to the activity of sludgeand effluent water quality. The pH of the alkaline wastewater equal to12,11.5and10.5,the impact time are3.4h,6.5h and7.6h when the oxidation ditch begins to be toxic. If the pH of the alkaline wastewater are12and11.5, impact2h, the effluent TP reached1.7and1.3times as the normal situation respectively, impact8h, the removal rate of TPdropped to6.99%and32.28%. pH of12and11.5alkaline impact had great impact tothe effluent concentrations of ammonia nitrogen, impact8h, the removal rate ofammonia nitrogen dropped from96%to82.91%and86.71%, but effluent ammoniaconcentration do not exceed the standard.With the impact of pH of12,11.5and10.5,both COD and TN exceed the standard. pH≤11.50alkaline wastewater impact8h, it iseasy to revert to the normal situation after taking appropriate control measures to8h,while pH with12.00could hardly recover.pH≤5acidic wastewater impact significantly on activity of activated sludge inoxidation ditch, the signs of intoxication within2h and the average SOUR value ofoxidation ditch activated sludge decreased by15%. Effluent TP is most sensitive to theimpact of acidic wastewater, the pH≤6acidic wastewater impact8h effluent TPexceeded the normal concentration, pH≤4acidic wastewater impact8h, the TP removalrate dropped to below50%. Ammonia is not sensitive to acidic wastewater impact, butpH≤4acidic wastewater impact, the effluent TN exceed the standard within2h, TNremoval rate dropped to below46%which impact8h. pH≥4.50acidic wastewaterimpact8h, it is easy to revert to the normal situation after taking appropriate controlmeasures to8h, while pH with4.00could hardly recover.Containing high concentrations of Cu²⁺industrial wastewater impact Orbaloxidation ditch system, the influence of activity of sludge and effluent quality obviouslylag. If Cu²⁺concentration of influent is8mg/L, impact8h, it has little effect on activityof sludge and effluent quality in oxidation ditch, and pollutant removal is consistentwith the normal state. If Cu²⁺concentration of influent are10mg/L and12mg/L, SOURvalue gradually reduce with the growth of the impact time, run to1920min, effluent TNconcentrations are22.71mg/L and23.47mg/L, the removal rate reduce to48.21%and44.58%respectively. The highest concentrations of effluent NH3-N and effluent TP upto3.7,1.5and4.4,1.6times as the normal situation.Compared accompanied water load with normal water load, the activity of sludgewas more significant inhibition of time in advance, storage or overflow of highpollution flow to avoid activated sludge system damage. Improving the sludge recycleratio can reduce the high proportion of industrial wastewater impact of activity ofsludge and the treatment effect. SOUR value and DO value has a strong consistency during the impact of the high proportion of industrial wastewater and the controlexperiment, therefore, increasing the amount of aeration can maintain the activity ofmicrobial biomass.