Research On The Treatment Of High-salt Mustard Tuber Wastewater By Physical Chemistry And Biochemistry

High-salt pickle wastewater includes many pollutants, such as high organic, highnitrogen and phosphorus, due to the high concentration, if the wastewater dischargeswithout disposal, it will cause a lot of damage to the environment. This paper wasseparately studied on the treatment of high-salt pickle wastewater using Fenton reagent,Electrochemical oxidation, ASBR （Anaerobic sequencing batch reactor） and ASBR-Electrochemical oxidation.①Fenton reagent was used to treat high-salt pickle wastewater,the test resultsshow that the maximum removal efficiency of COD and PO₄^3--P for the process was29.0%and15.4%respectively under the conditions of normal temperature, pH=4.4-5.0,the dosages of H₂O₂was80mmol/L, the moler ratio of H₂O₂/FeSO₄·7H₂O was4, andthe oxidation time was20min, after settling for20min, the pH was adjusted to6withNaOH, the maximum removal efficiency of COD and PO43--P could reach51.0%and99.5%respectively. Fenton reagent is limited on COD removal, and the dosage of H₂O₂is bigger, the cost for one ton wastewater is16.1yuan.②Electrochemical oxidation was used to treat high-salt pickle wastewater. Theanode was Ti/RuO₂-TiO₂-IrO₂-SnO₂expanded metal sheet electrode. The cathode wasexpanded metal sheet electrode. Current density, electrode plate interval and electrolytictime have a great influence on main pollutant removal. Experimental results show that:under the condition with current density113mA/cm2, electrode plate interval4cm,electrolytic time90min, the influent NH₃-N, TN, COD and PO₄^3--P concentration was161,496,6075,48mg/L, the effluent NH₃-N, TN, COD and PO₄^3--P concentrationachieved0,137,925,7mg/L, which removal rate achieved100%,72%85%and87%respectively. Under the condition with electrolytic time120min, COD can reach thethird grade discharge standard, the cost for one ton wastewater is90yuan. It is obviousthat only using Electrochemical oxidation will cause great power waste of resources.anddifficult to reach the discharge standard.③ASBR （Anaerobic sequencing batch reactor） was used to treat high-salt picklewastewater, the test results show that:The ASBR reactor started successfully, the reactor was used to pretreat high-saltpickle wastewater, the test results show that: under the condition with filler dosing ratio60%, HRT1d, the organic loading3.0kg COD/（m³d）, the temperature30℃, the influent NH3-N, TN, COD and PO₄^3--P concentration was138,537,5875,59mg/L, theeffluent NH3-N, TN, COD and PO₄^3--P concentration achieved396,500,1000,48mg/L,which removal rate achieved7%,87%and16%respectively.④The experiment of treating high-salt pickle wastewater by using thecombinative technology of “ASBR-Electrochemical oxidation” showed that:The effluent from the ASBR reactor was further treated by using Electrochemicaloxidation: The anode was Ti/RuO₂-TiO₂-IrO₂-SnO₂expanded metal sheet electrode. Thecathode was expanded metal sheet electrode, under the condition with current density88mA/cm², electrode plate interval2cm, electrolytic time10min, the influent NH3-N,TN, COD and PO₄^3--P concentration was386,496,625,48mg/L, the effluent NH3-N,TN, COD and PO₄^3--P concentration achieved219,339,375,42mg/L, which removalrate achieved43%,32%40%and13%respectively. the COD can reach the third gradedischarge standard, the cost for one ton wastewater is4.5yuan.ASBR was used to pretreat high-salt pickle wastewater, not only greatly reducesthe COD, and greatly reduces the TN, it is a feasible method.