Research On Engineering Design Of Wastewater Treatment And Biogas Utilization Of Wheat Starch

Starch has important applications in food industry and industrial production, there aremany factories which produce wheat starch in Henan and Anhui province in our country, andlarge quantity of wastewater are produced in the process of wheat starch production.If thewastewater are discharged into the the water directly without effective treatment, it will causeserious harm to the water.This thesis is based on the design and operation of the reconstructive project for treatingwastewater from a wheat starch factory in Anhui province. According to the characteristics ofwheat starch wastewater which have high organic concentration and good biodegradability,this paper’s key topic is to find a way more efficient and economic and resource recycling insewage treatment or biogas resource recovery project, in order to provide reference for wheatstarch industry wastewater treatment.According to the analysis of wheat starch wastewater and the past engineeringexperiences, the anaerobic MIC-aerobic HTO process was used as the main body to treat thewastewater based on the original project. This paper designs a wheat starch wastewatertreatment and biogas collection, purification and utilization system. The advantage of thisprocess is that the treated starch wastewater can meet emission requirements, while recyclingenergy generated by the anaerobic biological treatment. The capacity of wastewater treatmentis2000m3/d, COD=12000~20000mg/L, BOD5=6000~10000mg/L, SS=9000~10000mg/L.The operating records shows that this wastewater treatment process proposed in thispaper not only has a high COD removal efficiency, COD removal rate reached over95%, butalso has a significant removal effect for ammonia nitrogen removal, overcomes theshortcoming of poor nitrogen removal ability which exists in the traditional process, but alsorecycling biogas, biogas yield is10000-13000m3/d, used as the fuel of gas boilers. The steamproduced is used for workshop. The COD, BOD5, SS, NH3-N of treated wastewater wererespectively reduced to100mg/L,20mg/L,30mg/L,15mg/l, meet the indirect water pollutantsemission concentration limit for new enterprises in the "starch industrial water pollutantdischarge standards" GB25461-2010.The process has many advantages in stable operation, small footprint, energy saving andless maintenance cost. The project provides a practical and feasible approach to treat thewheat starch wastewater, can be applied to practice and spread by a model project. A win-win of environment protection and economic benefits can come true.