Experimental Study On Flux Performance Of Flate Ceramic Membrane In Mine Water Treatment

In most coal mining areas in China,there is a serious phenomenon of water pollution and waste.Long-term coal mining not only consumes a large amount of fresh water resources for coal washing and dust removal of fully mechanized mining and comprehensive excavation surface,but these used water and mine gushing water in mining process often contain a large number of toxic substances,such as coal dust particles,acidity and heavy metals,which will seriously affect the local ecological environment if not effectively treated and discharged.The traditional flocculation-sedimentation technology has some disadvantages,such as large area,easy residue of chemicals and so on.Some new treatment processes involve filtration of various membranes in deep treatment.As an emerging filtration and separation material,ceramic membrane has been widely used in water treatment because of its good chemical stability,high separation efficiency and long service life.In this paper,the designed ceramic membrane filtration device was used to filter the mine water containing coal dust,and the pollution of the ceramic membrane was analyzed theoretically.The flux variation of ceramic membrane under different operating conditions was determined by experiments.The effects of different aeration rates on critical pressure and flux were measured.The flux variation model of filtration process and the model after flux stabilization were proposed.Finally,the established flux model was fitted and validated by experimental data.In the experiment of pure water flux measurement,distilled water was filtered under different operating pressures,and the change of pure water flux with operating pressure in a certain range of pressure presented the first-order function.The critical pressure and flux of the ceramic membrane obtained by the pressure increment method were 4.7 k Pa and 160.56L/(h·m~2)respectively.The influence of aeration on critical pressure and flux of ceramic membrane was studied.By adding different aeration volumes to the filtration system,it was found that increasing aeration could slow the membrane fouling and increase the critical pressure and flux.The flux variation law under different pressures was measured,and it was found that the flux decreased slowly under the critical pressure,which proved that the filtration under the critical pressure could effectively reduce the fouling of ceramic membrane.Through the theoretical analysis of the pollution of ceramic membrane,the resistance change model at different pollution stages was obtained.The flux variation model of the ceramic membrane in the filtration process and the flux stability model were proposed.Finally,the established flux model was fitted and validated by the experimental data.