Study On Processes Debugging And Operation For Treatment Of Wastewater From Spice Industrial Park By UASB+A/O+BAF Method

Spices are a kind of important food additive and spice industry as a newindustrial department is experiencing a rapid development period. However, someindustrial wastewater of spices with high pollutant concentration are generated in theprocesses of spices production. Typically, the spice wastewater contains spices and itsbyproducts, degradation products， raw materials. Spice wastewater has thecharacteristics of high concentration of organic matter and high toxicity, it will causeserious damage to the environment and effect people’s health if direct emissions.This project focus on treatment of spices wastewater from spices industrial park.On the basis of fully analyzing water quality ingredients, combination technology of“Up-flow Anaerobic Sludge Bed (UASB)+anoxic/aerobic reactor (A/O)+biologicalaeration filter (BAF)" is used to deal with the wastewater. This paper aims attreatment system’s operation and debugging process after construction andinstallation process. After debugging preparation, unit process startup and onlinecombination process debugging, and optimization of three stages, start-up of thecombination process was successfully achieved, operation of the combination processwas stable, effect of wastewater treatment is well, and effluent reached 《Dischargestandard of pollutants for municipal wastewater treatment plant》(GB18918-2002)level1B standard. Conclusions was summarized below.(1) COD concentration of influent was between400~500mg/L, average CODvalue was about450mg/L. COD value of the final effluent was stable below60mg/L,total COD removal efficiency can reach90%.(2) Ammonia nitrogen concentration of influent was around60mg/L.ammonification of UASB was significantly, and effluent ammonia concentration canbe increased by8%. After the combination process of ammonia nitrogen nitrificationis completely, the water ammonia nitrogen under8mg/L, total ammonia nitrogenremoval rate can reach more than95%. Combined process treatment of nitrificationwas complete, ammonia nitrogen concentration of effluent was below8mg/L, totalammonia nitrogen removal efficiency was more than95%. (3) Total nitrogen concentration of influent was about80mg/L, effect ofdenitrification was obvious, the effluent total nitrogen was stable below20mg/L aftertreatment, the total nitrogen removal rate could reach about80%.(4) For spices industrial park wastewater, COD concentration could be removedsignificantly by “UASB+A/O+BAF” process. However, the UASB unit process forCOD removal rate should not be too high, otherwise subsequent A/O denitrificationprocess would appear the problem of insufficient carbon source easily to affect thetotal nitrogen removal efficiency.(5) Through reducing hydraulic residence time of the UASB process andincreasing the internal reflux ratio of mixed solution in A/O tank, the shortage ofcarbon source and low efficiency of nitrogen removal for denitrfication process couldbe effectively solved.The results and experience of this debugging project has practical significancefor wastewater treatment experiment and wastewater treatment engineeringapplication.