Research On The Treatment Of Pharmaceutical Wastewater By Catalytic Oxidation Method

Since the pharmaceutical wastewater has kinds of compounds, lowbiodegradability The important pollutants such as COD are out of criterion, thetreatment of pharmaceutical wastewater is considered the one of the most difficulttreatments for most of pharmaceutical companies. So,in order to improve itsbiodegradability, we should pretreat the water.In this experiments, we treated thespecial pharmaceutical wastewater with coagulation/activated carbonadsorption/catalytic oxidation method,then studied the effect to increase treatmentefficiency, researched the principle of the degradation.At last, We achieved severalconclusions as following:1 Research on treating pharmaceutical wastewater by coagulation.Through the pharmaceutical wastewater pretreatment experiments and theanalysis of the effect of several coagulant and cost, ferric chloride was selectd as theappropriate coagulant, the coagulation conditions were as follows: pH=8 , mixed-phasespeed of 400r/min, the mixing time is 30 s; Stage of the reaction conditions are asfollows: reaction speed stage 70r/min, the reaction time was 15 min, 0.002kg.ferricchloride was put into one wastewater. After checking, it meet the conditionrequirement of reaction phase and coagulation. After treatment, the turbidity and theSS of wastewater reduce to 92% and 75%, coming up to the standard of SS inwastewater discharge. Meanwhile, the COD concentration and sulfate concentrationdecreased by 18% and 35%, which providing convenience to the subsequent treatment.2 Research on activated carbon adsorbing pharmaceutical wastewaterThe test research the impact of activated carbon adsorption factors and the effectof COD concentration decrease of the wastewater, and pH value is the majorinfluencing factors in activated carbon adsorbing wastewater. In the pH of 7, using 200 of activated carbon per one ton wastewater can be achieved the best effect。The CODremoval rate reached 31.6%, and the costs of treating one ton wastewater is about 10Yuan.3 Research on the treatment of pharmaceutical wastewater by catalytic oxidationmethodWastewater produced from pharmaceutical wastewater treated by catalyticoxidation method. The research showed that the COD elimination rate was affected bypH value, reaction time, temperature, and oxidant quantities. Basing on the experimentresults > treatment effect cost analysis, we choosed iron catalyst as the final choice forthe treatment of this pharmaceutical wastewater, and the suitable reaction conditionswere as follows: pH=5, temperature:30(°C), reaction time:1.5h,the amount of catalyst:2.5 g/L(mass ratio of Fe～(2+)/Fe_～(3+)is 2:3.), the ratio of hydrogen peroxide: 4.7%, CODremoval rate reaching 91 percent.. According to the pharmaceutical market prices, thecost of one ton of waste water treated by iron catalyst hydrogen peroxide wasestimated to 32 Yuan.4 Total costs accountingAccording to respectively cost analysis of the three-step test, the total cost oftreating one ton pharmaceutical wastewater by coagulation/activated carbonadsorption/catalytic oxidation method was estimated : 0.8+10+32=42.8yuan, less thanconventional approach to the cost of pharmaceutical wastewater.5 Study on the kinetics of catalytic oxidation of xanthate sodium containing wastewaterAccording to the treatment of pharmaceutical wastewater by catalytic oxidationmethod and quantitative analysis under certain conditions, we can calculate theapparent rate constants and the activation energy of dynamic response. The oxidationreaction is a first-order reaction, and the kinetic equation for the oxidation reaction ofxanthate sodium was established and which is found to suit the experimental data quitewell, and kinetic model is as follow:(?)...