Study On Advanced Treatment Of Pharmaceutical Wastewater By Biological-activated Carbon Process

In recent years,with the rapid development of the pharmaceutical industry,the advanced treatment of pharmaceutical wastewater is also more and more important.Pharmaceutical wastewater treatment methods are diverse,so it is very important to choose the appropriate processing technology.In this paper,the two methods are combined,which is the combination of biological and activated carbon adsorption method.Experimental pharmaceutical wastewater is biochemical effluent,which belongs to a pharmaceutical factory in Harbin.By comparing the treatment effect of different biological methods,as well as the optimization of electrochemical regeneration conditions,to achieve the recycling of activated carbon.As the same time,to achieve the purpose of improving the quality of pharmaceutical wastewater effluent.In the experiment of biological system,the optimum operating conditions of different biological systems are determined,and different biological treatment systems are compared,meanwhile,the optimal biological treatment system are selected.Among them,No.1 and No.2 treatment system are SBBR reactor under microaerobic condition,volcanic rocks are selected as fillers in No.1 reactor,and a new suspended filler is selected as fillers in No.2 reactor.No.3 and No.4 treatment systems are SBR reactors,each of which is under microaerobic and aerobic condition.In addition,the rest of the operating conditions are identical.The results shows that under the optimum operating conditions,the advanced treatment effect of the No.2 reactor on the pharmaceutical wastewater is the best,which COD removal rate is 17%.In the study of the effluent of activated carbon adsorption biological treatment system,the factors such as dosage and adsorption time of the activated carbon are determined,at the same time,the adsorption isotherm and kinetics of the adsorption process of activated carbon are analyzed.The results show that the optimum operation condition of activated carbon adsorption is 3 g/L and 12 h,the p H value in the reaction system has little effect on the performance of activated carbon adsorption.It is found that pseudo-2nd-order kinetic model can better describe the dynamic process of activated carbon adsorption.The type of the adsorption process is Freundlich,it can be seen that the adsorption of pharmaceutical wastewater is a mixed adsorption process.After this process,the effluent of pharmaceutical wastewater can meet the requirements of 1 B of discharge standard of pollutants for municipal wastewater treatment plant(GB 18918-2002).In the study of electrochemical regeneration of saturated activated carbonprocess,effects of different factors on the electrochemical regeneration are discussed.The main contents include: the influence of current,electrolyte concentration,energization time,and so on.Meanwhile,the optimum electrochemical regeneration conditions are determined to achieve regeneration of activated carbon in situ.The optimum experimental conditions are as follows: the regenerative current is 1 A,the concentration of electrolyte(Na Cl solution)is 2g/L,and the regeneration time is 2 h.At the same time,the optimal cycles of activated carbon is 3 times.