Study On The Treatment Of Mariculture Wastewater By Ozone/Modified Biochar System

With the rapid development of mariculture industry in China,the mariculture mode has developed in the direction of industrial aquaculture.Meanwhile,the threat of mariculture wastewater discharge to the surrounding water environment is becoming more and more prominent.In this paper,the mariculture wastewater of Huludao City,Liaoning Province was taken as the research object,and simulated wastewater with the same water quality was configured.The removal effect of pollutants in mariculture wastewater by ozone alone and Ozone/modified biochar System was studied respectively,and the degradation kinetics of organic compounds was analyzed,in order to compare the reaction rate constant.Further analysis of ozone alone and Ozone/modified biochar Systems was carried out.The main findings of this article are as follows:When the ozone flow rate was 1.0 L/min,the wastewater p H was 9,and the salinity was maintained at 30‰,the mariculture wastewater was treated by ozone for 60 minutes,the removal rate of NH₄⁺-N in the wastewater reached 72.09%,the removal rate of NO₂^--N and COD are relatively lower at 36.04%and 34.12%.The initial p H value,ozone flow rate and salinity had a greater impact on the removal of wastewater pollutants.The effect and influence of modified biochar on ozone treated wastewater were investigated.The results indicate that the removal rate of NH₄⁺-N,NO₃^--N and COD in wastewater has been improved with the increase of the modified biochar dosage.Change of initial wastewater p H had a greater impact on the inorganic salts in treatment wastewater by Ozone/modified biochar,and had little impact on the removing of organic matter.The effect of salinity on the Ozone/modified biochar System was similar to that of ozone alone.When the ozone flow rate of 1.0 L/min,p H was 7,the modified biochar dosage was 2.0 g/L,and the salinity was maintained at 30‰,the Ozone/modified biochar system achieved good treatment effect on mariculture wastewater,and the removal rates of NH₄⁺-N,NO₂^--N,NO₃^--N and COD were 88.35%,100%,91.03%and69.72%.It was found that the removal of organic compounds in mariculture wastewater by the two methods was a rapid reaction within 40 min,and then gradually leveled off.Therefore,the segmentation fitting of the reaction can better analyze the two treatment method.The kinetic fitting analysis of Ozone/modified biochar System for degradation of organic matter was carried out,and the reaction order was determined by direct substitution method,and verified by differential method,the Ozone/modified biochar System could be fitted by first-order kinetics,and the fitting effect was good.The results showed that the COD removal rate and effect of Ozone/modified biochar System were much higher than that of ozone alone.