Study On Lowing Energy Consumption And Optimizing Operation Of SBR Process

On the first day of 2015, the new law of environment protection was implemented formally which was called the most strict law in the history,on the 16 th of April in the same year, ten policies about water of state coucil was issued. The discharge standard of municipal wastewater was improved from level B?GB 18918-2002?to level A?GB 18918-2002?,and to incentive IV class next?GB 18918-2002?.The higher and higher standard of the effluent put accordingly high requirements to the built wastewter treatment plants. On one hand,high standards make the consumption of the energy increased, which increase the cost of the treatment.On the other hand, the limited volume of the tank,the big difficulty of technical innovation and the limited resources make it hard for many built wastewater treatment plants to meet the new standards, and most of them are faced with the pressure of how to realize the low energy consumption and complete the upgrade under the current technological conditions. The essay is about the upgrading research of the wastewater treatment plants in Chaohu Watershed which SBR craft was chosen as the main process, the main point of the study is how to low the treatment cost and improve the removal rate of the nitrogen and phorsphorous. Through the analysis of the inffluent,we can see that the carbon nitrogen ratio of the plant is relatively low,the average concentration of COD in the year of 2015 is 203mg/L, the average concentration of TN is 37.15mg/L,the average carbon nitrogen ratio of the inffluent is 5.46,the needed carbon resources for denitrification is seriously insufficient, so the extra carbon resources was needed to improve the rate of the denitrification. We determine the aerated grit chamber ? biological pool biological selection area and advanced treatment as the main unit to upgrade the operation of the plants and realize the saving energy and lowong consumption by analying the current operation situations. The comparison and analysis of the small test for the current carbon adding plan in the wastewater treatment plant,the result shows that,making the inffluent from 8 to 9 AM as the raw water, adding sodium acetate as extra carbon source has no effect on the concentrations of COD and NH₄⁺-N of the effluent,while the removal rate of the NO₃^--Nincreased 17.30%. The concentrations of COD and NH₄⁺-N of the effluent remain unchanged when the flooding time was contracted from one hour to 20 minutes,while the removal rate of the NO₃^--N increased 6.52%.The concentrations of COD and NH₄⁺-N of the effluent for two reactors had no difference, the removal rate of the NO₃^--N increased 14.77%. The main water quality indicators before and after the two hour water precipitation show that the change of the concentration of ammonia nitrigen and phosphate is small,which was opposite of the TP and COD,before the precipitation,the maxmium concentration of TP was 8.65mg/L,while after precipitation was 1.66mg/L,the concentration of COD decreased 50%.In inner denification test, in the reactor whose average COD concentrations is similar to 2015s',the removal situations of NO₃^--N was not in line with the expections, the removal amount of NO₃^--N in an hour was 3.26mg/L?2.84 mg/L?2.29 mg/L respectively, there is no NO₃^--N in 220 minutes.The removal amount which only depended on the inner denitrification in anhour was 1.04 mg/L?1.87 mg/L?2.22 mg/L?2.15 mg/L respectively. At last, the analysis of wter short flow phenomenon in the SBR biological tank biological selection section,the result shows that the influent amount of biological selection area which make up the 9.9 percent volume of the whole biological tank make up 24.89 percent of the whole influent amount, the most part of the carbon source was wasted in the biological selection area and couldn't be nitrified,when diffused into main section of the device, the concentration of NH₄⁺-N was improved. After the modification, the denitrification rate of nitrate can reach 78.8%, while the original removal rate was only 57.2%,the effect of the technical modification is obvious.