Technology Of High Concentration Manganese Wastewater Treatment In The Same Cell

High concentration manganese wastewater mainly comes from the production process of manganese metal,which causes great waste of resources and serious environmental pollution.In order to solve the problem of high concentration manganese wastewater produced in the traditional production of manganese metal,through the intersection of water treatment and metallurgy,using the excellent selective permeability of ion exchange membrane,combined with the characteristics of wastewater,a single membrane double chamber electrolytic recovery process is designed Two kinds of technical schemes of the same cell electrolytic treatment of high concentration manganese containing wastewater and two membrane three chamber electrolytic recovery process are proposed.While realizing the treatment of high concentration manganese containing wastewater,the recovery of manganese products is realized.Through the experiment,the advantages and disadvantages of the two are compared,and the best treatment process and operation conditions are finally determined.In this study,In this study,the neutral MnSO₄-?NH₄?₂SO₄-H₂O electrolyte system is taken as the experimental object,and two kinds of electrolytic recovery processes,i.e.double membrane three chamber and single membrane two chamber,are used for comparative experiment,theoretical analysis and experimental simulation,and preliminary experimental research is carried out by using single factor analysis.Taking the output of cathode anode products,current efficiency and electrolytic energy consumption as evaluation indexes,the concentration of cathode Mn²⁺is studied The influences of cathode plate material,cathode current density,electrolyte temperature,electrolyte p H,additive SeO₂ concentration and anode temperature,sulfuric acid concentration,anode current density,anode plate material and other factors on different electrolysis conditions were preliminarily determined,and the reasonable range of influencing parameters of anode and cathode electrodialysis was preliminarily determined;single factor analysis showed that:within a certain range,The concentration of cathode Mn²⁺directly affects the voltage,energy consumption and current efficiency of the initial cell.Too low or too high concentration of Mn²⁺will affect the product deposition form.In the process of double membrane three chamber recovery,it also affects the acid recovery rate of the middle compartment.The concentration of Mn²⁺in electrolysis is controlled between 35-41g/L,which is the best.The performance of energy consumption,cell voltage and product stripping in the process of electrolysis should be considered in the selection of plate The results show that:stainless steel plate is the best choice for cathode plate;cathode current density affects electrode reaction rate,cell voltage,product deposition,current efficiency and energy consumption,and too large current density will cause plate peeling and"bursting"phenomenon,which is not conducive to the operation of the electrolysis system,and the cathode current density is maintained between 350?400A/m²for better electrolysis condition Temperature has an effect on product form,current efficiency and cell voltage,which significantly affects the form of manganese dioxide in anode compartment.When the temperature rises,the"hydrogen evolution"reaction will aggravate,which will reduce the current efficiency,but too high temperature will not only affect the product quality,but also destroy the operation of the electrolytic system when the temperature exceeds 50?.35??37?is the best electrolysis temperature;pH mainly affects the operation condition of cathode,and the change of pH will affect the current efficiency and cell voltage.The high pH of cathode will affect the deposition of products.Under the low pH condition,the phenomenon of"peeling off"is very easy to occur in the initial stage,and the initial pH is less than 7,resulting in the deposition of the surface layer of cathode plate is not dense enough and easy to peel off,which is not conducive to the operation of electrolysis for a long time.It is the best to maintain the comprehensive pH range between 7.0 and 7.2;the additive SeO₂ not only affects the current efficiency,but also facilitates the phase transformation of manganese metal deposition.After adding the additive,the solution as a whole has a certain reducibility,which is more conducive to the stable operation of electrolysis.It is found that the concentration of SeO₂ is 0.03-0.04g/L,which is the best;the anode current density affects the shape and output of manganese dioxide,which is about800A/m² Good condition;acid concentration mainly affects the output of manganese dioxide in the two film three chamber electrolytic recovery process,taking into account the economic and electrolytic operation conditions,the best sulfuric acid concentration is about 2.5mol/L;anode plate titanium coated lead dioxide plate and titanium coated iridium can be selected flexibly according to the needs.The specific range of each factor under the optimal condition of electrolytic recovery was determined by using the orthogonal experiment.The overall condition was in accordance with the results of single factor analysis.The cathode current density and the anode acid concentration had the most significant influence on the negative and anode conditions,and the electrolytic conditions did not change much in different electrolytic recovery processes.The biggest difference was that titanium coated iridium electrode should be used as the anode of single film double chamber process Titanium coated lead dioxide plate is suitable for plate and double film three chamber process anode.Through a large number of experiments and comparisons,it is found that ion-exchange membrane electrolysis technology can not only deal with high concentration manganese containing wastewater,solve the problem of pollution and discharge of high concentration manganese containing wastewater in traditional electrolysis production process,but also realize the product recycling and produce certain economic value.At the same time,it can provide new ideas for the improvement of manganese production process,and solve the problem of production of traditional manganese metal preparation process Single product,waste of resources and energy,and environmental pollution.At the same time of simultaneous recovery of metal manganese and manganese dioxide,it also realizes the recovery and reuse of acid,reduces energy consumption,and further improves production capacity and economic benefits.There are advantages and disadvantages of the two membrane three chamber recovery process and the single membrane two chamber recovery process.From the perspective of product economic benefits,the two membrane three chamber recovery process has obvious advantages,with high product diversity,especially the products on one side of the anode compartment can also produce huge economic benefits.In practical application,combined with the current global supply and demand relationship of manganese dioxide,only domestic manganese metal production enterprises use the two membrane The three chamber recycling process will lead to the situation that the global manganese dioxide market is oversupplied,and the investment of ancillary system construction is large,and the economic benefit of small-scale production is not high;the application of single membrane double chamber recycling process in the treatment of high concentration manganese containing wastewater can realize wastewater treatment and recycling,solve the serious pollution problems in the current traditional production,and also improve the traditional gold It is a manganese production process with simple process structure,adjustable output of anode manganese dioxide,low investment cost and energy consumption.Comparing the advantages and disadvantages of each process,considering the economic benefits of the product and the current production situation of domestic enterprises,as well as the investment cost problems faced by the international manganese product demand and process investment,the single membrane double chamber electrolytic recovery process is the most current one Good choice.Although this project is still in the initial stage of exploration and limited to laboratory research,it still faces many constraints of influencing factors,especially under the current global supply-demand relationship of manganese products,the huge difference in the demand for manganese and manganese dioxide leads to a wide range of process improvement difficulties,and the process itself has certain requirements for the performance of ion exchange membrane,so the performance is excellent The high cost of ion exchange membrane is also one of the important constraints to be overcome.However,the unique selective permeability of ion exchange membrane has great advantages in the application of industrial wastewater treatment.The combination of ion exchange membrane and electrodeposition technology will provide a new idea for industrial wastewater treatment.In this paper,the ion exchange membrane will be studied The combination of membrane and electrodeposition technology in the treatment of Mn²⁺in the recovered wastewater provides a new research idea for the new application of electrodeposition in the same cell in the manganese electrolysis industry to a certain extent,and plays a positive role in promoting the recycling of wastewater.