Research On The Feasibility And Application Of The Harmless Treatment Of Electrolytic Manganese Residue By Solar Electric Power

As the basic raw material in our country's industrial development,manganese metal is called"industrial monosodium glutamate",and its sustainable development model affects the process of our country's modern industrial development.However,due to the limitations of the current metal manganese production technique and resource recovery technology,a large amount of solid waste electrolytic manganese residue(EMR)is generated,and a serious waste of land resources is caused in the landfill process.Studies have found that EMR and its leachate contain a large amount of ammonia nitrogen,manganese ions,and various compound salts that are difficult to be treated.The transferable ions with rain or surface water into the surrounding environment will cause serious pollution.Therefore,achieving compound salts decomposition,and removing or solidifying the ammonia nitrogen and manganese ions in the EMR is the key to the harmless treatment of the EMR.From the perspective of sustainable development,the harmless treatment of EMR based on green,economic and large-scale EMR is an important means to solve environmental problems and contradictions between people and land.Therefore,based on the basic principles of electrodynamics and electrocatalytic oxidation,this thesis adopts solar electrodynamic harmless treatment of EMR.The feasibility of using solar energy,element migration and phase transformation of EMR in the process of harmless treatment,and the strengthening method of solar harmless treatment of EMR were explored respectively.Then,the application research of solar harmless treatment of EMR was carried out,and the main conclusions were as follows:(1)It proved the feasibility of using solar electric power to process EMR.Compared with DC power supply,when using solar energy to treat EMR in a sunny day,the difference in removal effect of ammonia nitrogen and manganese ions was less than5%;in cloudy and rainy days,the treatment level of EMR reached 70%of DC power supply.After appropriately prolonging the processing time,the solar energy can reach the level of DC power treatment.In addition,the solar energy system can also save about 460.80 k W·h/t of power consumption,effectively reducing the treatment cost of EMR.(2)Under the action of electric field,NH₄⁺-N and manganese ions migrate to the cathode directionally.In the cathode,NH₄⁺-N combines with SO₄^2-to form(NH₄)₂SO₄crystals that can be easily separated.Mn²⁺combines with OH^-produced by cathodic electrolysis of water to form Mn(OH)₂,which can solidify and stabilize Mn²⁺.When the solar panel stops supplying energy,a part of Mn(OH)₂ will be oxidized by O₂ in the air to Mn OOH.In addition,under the catalytic oxidation of DSA plate,Cl-can assist the decomposition of(NH₄)₂(Mg,Mn,Fe)(SO₄)₂·6H₂O and other compound salts in EMR,which is helpful to promote the treatment process of EMR from harm reduction to harmless.(3)After 96 h treatment,the manganese ion concentration and ammonia nitrogen content of the EMR in the anode and cathode region can reach the first-level discharge index of the National Comprehensive Wastewater Discharge Standard.At the same time,the cooperative and efficient treatment of EMR and manganese residue leachate can be realized.The ammonia nitrogen content in manganese residue leachate can reach the second-level standard of corresponding sewage discharge of enterprises after treatment,and the manganese ion concentration in the cathode area can reach the first-level standard.The ammonium sulfate crystals produced in the cathode region can be recovered intensively with a recovery rate of 57.70%.(4)We proved the application of the harmless treatment of EMR by solar energy was feasible.The toxicity of EMR and its leachate decreased with the increase of treatment time.After a period of 15 days of treatment of 1.4 t EMR,the reduction of manganese ion concentration was more than 25%,and the reduction of ammonia nitrogen content was more than 30%,which was effectively controlled.The moisture content of the EMR was improved,and the harm reduction treatment of large quantities of EMR was realized.The above research results provided the theoretical guidance and data support for the green,economic and large-scale processing of EMR,and also produced a part of the foundation for the realization of resource utilization of EMR,which had good academic significance and application value.