Try And Research On Chroma And COD Adsorbents Treatment Of Coking Wastewater Effluent Which Has Been Treated By Biochemical Processes

Coking wastewater was produced in the progresses that cracking coal under high temperature to get coke and coal gas and reclaiming byproducts such as tar and benzene.Components were complex in coke plant wastewater, in which contains refractory organic compounds such as tar, benzene, phenol, cyanide, quinoline and pyridine etc. So chroma of that is high ,and great changes happened usually to water quality and water flow. It is a typical industrial wastewater, in which contains a number of toxic and nocuousness compounds. The removal rate of chroma and COD was not favorable by using biological treatment processes separately, and the effluent concentration could not attain the wastewater drainage level which brought severe harm to our environment and communities. It had been demonstrated that adopting the assembled processes adsorbents could effectively reduce chroma and COD of coking wastewater effluent which has been treated by biochemical processes, and made it reach《The reclaimed water reuse Standard》.In this research,include the Static experiment(include the methods of single factor and perpendicularity experimental analysis) and the dynamic experiment,were used to acertain the four absorbents:the semicoke,the active carboon,the coke,and the fly ash. From a coking plant in Taiyuan City station by grease wastewater treatment, air flotation, anaerobic, anoxic, aerobic and final processing by the secondary sedimentation tank of water (where water quality is CODcr=197.64~264.31mg/L,NH3-N=16.4~37.62mg/L,PH=7~10,chroma≈180) treated by the BAF water depth as the test the main use of water, the water quality is CODcr≈60mg/L,NH3-N≈1.8mg/L,PH≈6~8,chroma≈75.The best treatment results of this research are as follows:(1) With the use of single factor analysis, analysis five factors,include the quantities of throwing, pH values, temperature, the sizise of adsorbents, and the different qualities of water,impact on four adsorbments,the resulte is:a. single factor of activated carbon in a variety of circumstances (other conditions unchanged), the effect of the best dosage of 400mg, the effects of removal of COD for 69.4%, decolorizing effect of 73.2%; pH value of 3, COD remove the effect of 80.1%, 90.4% decolorization effect; the effect of temperature on decolorization was the best 50℃, the removal rate was 95.0%, removal of COD in 60℃, the removal rate was 88.4%; The best sizise of absorbent at 0.45mm~2.0mm.b. Semi-coke in a variety of single factors (other conditions unchanged), the effect of the best dosage of 400mg, the effects of removal of COD for 65.0%, decolorizing effect of 77.8%; pH value of 3, to In addition to the effects of COD for 78.3%, 92.3% decolorization effect; the effect of temperature on decolorization was the best 55℃, the removal rate was 96.0%, removal of COD in 60℃, the removal rate was 85.4%;The best sizise of absorbent at 0.45mm~2.0mm.c. coke single factor in a variety of circumstances (other conditions unchanged), the effect of the best dosage of 400mg, the effects of removal of COD for 60.8%, decolorizing effect of 68.1%; pH value of 3, COD remove the effect of 72.1%, 86.8% decolorization effect; the effect of temperature on decolorization was the best 55℃, the removal rate was 94.6%, removal of COD in 60℃, the removal rate was 82.4%;The best sizise of absorbent at 0.45mm~2.0mm.d. Fly in a variety of single factors (other conditions unchanged), the effect of the best dosage of 400mg, the effects of removal of COD for 35.3%, decolorizing effect of 40.2%; pH value of 3, to remove the effect of COD for 45.1%, 51.3% decolorization effect; the effect of temperature on decolorization was the best 45℃, the removal rate was 57.1%, removal of COD in 60℃, the removal rate was 57.2%;The best sizise of absorbent at 0.45mm~2.0mm.e. The four absorbents is similar what in different qualities of water , but in the fact of high pollution of coking wastewater and overall performance the for absorbents are semicoke , the active carboon , coke , fly ash. This is yet another validation in dealing with the waste water coking, coking waste water generated in the process of coke and semi-coke for its one point advantage for me to provide an in-depth study in the right direction. The absorbent in the single-factor performance in front of the treatment effect is true that some factors that can be achieved even at the national level emission standards, but still less than the majority of this standard.(2) The best pH value, temperature and throwing quantities of semicoke, the active carboon, coke, and fly ash were found out with the use of perpendicularity experimental design. semicoke was more effective than the other three absorbents, and removal rate of chroma was 96.7%; besides, removal rate of COD was 74.3%.(3) The penetration of absorbents experiment,understanding of the removal CODcr of the max absorption capacity. In the same experiment condition, takes 25g absorbent ,which sizise is at 0.45mm~2.0mm., into the 100mm diameter of the cylinder. The quality of water is ,CODcr is about 60mg/L, chroma is 75 times, what comes from deepen treatmen coking wastewater by BAF. The four absorbents , the active carboon, semicoke, coke, and fly ash,what the longest time of penetration is 330min,300min,240min,210min.(4) Absorbents assay for the order to be able to get more data on the absorbent in the practical application of the actual results, experimne need determine the storey which was in the best absorption effect.The basic condition of experiment is similar to the peretration experiment, the cylinder filled with adsorbent, Water way below water, bottom-up column on 50mm at the mouth of a water testing to detect the different layers of high-quality water. After experiments in four of activated carbon adsorbent, the semicoke, coke and fly ash reach the needed of《The reclaimed water reused Standard》that the chroma≤40 times, CODcr≤50mg/L which storey is 85mm,85mm,85mm and 185mm.(5) Comparison of the adsorption of the four absorbents effect of economic analysis on waste water treatment costs and deal with absorbent effect of a comprehensive comparison test to determine this issue to deal with chemical and biological coking wastewater effluent absorbent for the best: semi-coke, acquisition cost of the adsorbent per ton less than one-tenth of the traditional activated carbon adsorbent and operating cost of about 60% of activated carbon, that is, operating costs per ton of wastewater treatment is only 0.58 yuan, and its effect on adsorption and activated carbon is not much difference .