Study On The Key Technological Process Of Microbial Treatment Of Urban Restaurant Nutritious Organic Wastewater

Globalization and the continuous growth in economic development as well as a better living standard of the people have resulted in the increase of restaurants and food industries all over the world.In Lanzhou and the country at large,Wastewater from food industries that is been release into the environment without adequate treatment has increase tremendously in recent times.This has attracted the government attention and efforts are been made on daily basis to make laws that will control the discharge of this wastewater into the environment.The constituent of food wastewater pollutants such as oil and organic matters have been observed to have adverse effects on the environment as well as human health.These adverse effects can be attributed to the increasing use of restaurants and food industries wastewater as well as the indiscriminate discharge of wastewater by these industries into water bodies and drains.Lanzhou is the capital and largest city of Gansu Province in Northwest China.The prefecture-level city,located on the banks of the Yellow River has witness enormous development in recent times in terms of infrastructures and industrialization.This has lead to the use of more water and therefore leading to more wastewater as runoff in the system.It has become imperative socially and economically to find lasting solution to this water pollution problems in this region.In this paper,Lanzhou restaurant wastewater was used as our research case study.The pollutant content(BOD5,CODcr,SS,TN,TP,NH3-N,LAS,pH,FOGS)and other indicators of the wastewater collected was inspected and analyzed.Microbial and physical treatment methods was used to design suitable,easy to operate,cost effective composite wastewater treatment processing technology with recycling ability and with no secondary pollution effect.(1)All the pollutants indicators BOD5,CODcr,SS,TN,TP,NH3-N,LAS,pH,oil,etc.were assayed and analyzed by GB method to obtained a firsthand data of the pollutant constituent of Lanzhou restaurant wastewater.Three indicators(TN,NH3-N and pH)did not exceed the national water quality standard B,while the other 7 indicators results value were higher than the national water quality standards B,The result obtained was used to further understand the pollutant characteristics which provide important basis for further research work.(2)Haven studied the pollutant constituent and in response to the content of CODcr,TP and BOD5 discovered,we studied and designed a wastewater treatment technology comprising of four major technological parts(aerobic,anaerobic,immobilization and physical adsorption)as well as with the best and easy to operate technological techniques and methods which enhanced high efficiency of restaurant wastewater treatment process.Experimental set up related parameters were calculated and design.(3)The anaerobic baffled reactor(ABR)had a strong shock and organic loading capacity,and improved the efficiency of wastewater treatment during the course of the whole experimental operation by adding denitrifying compound powder.The acclimation of anaerobic sludge was carried out for a period of 35 days with 7 cycles.Acclimation process of the anaerobic sludge was carried out at a temperature range of 20-30℃.ABR stability was attained at HRT 20 h,pH range of 6.5-7.5,and an average temperature of 25℃,the results showed that the anaerobic treatment efficiency of restaurant wastewater pollutants,especially CODcr,BOD5 and SS was satisfactory.The range of the removal rate attained was 77.3-87.2%.(4)Biological contact oxidation process is an efficient,simple and efficient water treatment process.During the Biological contact oxidation treatment process,an efficient intermittent aeration method,with the addition of certain amount of nitrifying bacteria powder at every cycle was employed.Acclimation of aerobic activated sludge was carried out for 40 days with 8 cycles.And with the inclusion of immobilization technology using polyurethane foam as carrier during the operational process,the results showed that immobilization could improve the treatment efficiency of wastewater.In order to further improve the treatment effect of wastewater,we designed a low cost physical adsorption process,using slag,quartz sand and activated carbon as the adsorption material,the combination of the three materials had the best effect.(5)The dominant bacteria were obtained from the activated sludge by separation and purification technology.7 strains of bacteria and 10 strains of fungi were obtained.The degradation mechanism of dominant bacteria to the food and beverage wastewater was analyzed(6)Experimental study on a small-scale medium using the standardized wastewater treatment equipments and set up shows that the wastewater effluent reaches the Nation National water quality standard B.The experimental study of the restaurant wastewater treatment process at the laboratory level using the designed cost effective,easy to operate and without secondary pollution effect,composite wastewater treatment processing technology shows that all the effluent indicators meet "urban sewage treatment plant pollutant discharge standard"(GB18918-2002)level B,.This experimental study should be applied in a large scale wastewater remediation process to ascertain its efficiency to the larger populace.