Expeirmental Studies On Iron-carbon Micro-electrolysis To The Preprocessing Of Paper-pulping Black Liquor

Environmental pollution caused by the pulp and paper industry wastewater dischargeis very large. The latest pulp and paper industry pollution emissions standards inGB3544-2008, which increased the waste water color and another4indicators, COD andother indicators were made more stringent limit. The black liquor of pulp and paperwastewater treatment is difficult, there is an urgent need to study a new type of black liquortreatment.In recent years,treatment effect of micro-electrolysis was significantly less investment,low running costs,practicality, has been studied and used extensively in bio-degradablewastewater,such as dyes,printing and dyeing,pesticides,pharmaceuticals and otherindustrial wastewater treatment.The use of micro-electrolysis for pretreatment by means ofthe chain scission of the macromolecular organic pollutants,resulting in color,and help thechromophore decolorization,and improve the wastewater biodegradability, to facilitate theconduct of follow-up biochemical reactions.The iron-carbon micro-electrolysis integratedflocculation,adsorption,bridges,swept volume,coprecipitation,electrodeposition,theelectrochemical reduction of a variety of role in the formation of the combined effect,hasnot yet formed in the field of pulp and paper wastewater systems theory and technology.In this paper,chose black liquor as test object which from a paper mill inXuancheng. Selected the iron-carbon micro-electrolysis to remove black liquor pollution.Orthogonal and single factor analysis determined the main factors affecting themicro-electrolysis treatment effect. got the best conditions for the iron-carbonmicro-electrolysis to pretreat pulping black liquor, designed a set of iron-carbonmicro-electrolysis continuous flow reactor,and iron-carbon micro-electrolysis of blackliquor, and established the factors affecting the micro-electrolysis, design a set ofiron-carbon micro-electrolysis reaction continuous flow device, and on base of orthogonaltrial, verified the results of the iron-carbon micro-electrolysis in the conditions ofcontinuous operation. The main conclusions are as follows:1. Under static conditions,elected pH,reaction time,the iron-carbon volume ratio,thehot metal volume ratio as factors.Designed orthogonal experiment L9.The results showthat,followed by pH, reaction time, iron-carbon volume ratio, the volume of molten iron,single-factor optimization experiments, the optimum reaction conditions the pH was3, thereaction time was30minute,the iron-carbon volume ratio of3:1, the metal volume ratio of 1:6.2. Under continuous operating conditions,refer to the parameters obtained by thestatic test,verify that the treatment effect of iron-carbon micro-electrolysis of black liquorof pulp and paper,the results show that the iron-carbon micro-electrolysis under theoptimum reaction conditions,the removal rate of CODCr73.06%,89.36%color removal, theTOC removal efficiency of65.35%of UV254,removal efficiency of85.86%,the treatmenteffect is obvious.Experiments show that the iron-carbon micro-electrolysis method for effectivegovernance of the black liquor of pulp and paper, reduce the emissions of pollution ofblack liquor, the governance model by Waste, economic and environmental benefitssimultaneously.