Study On Water Treatment And Plugging Performance Based On RC01 Sand-based Permeable Brick

There are certain similarities in structure and performance between permeable bricks and permeable concrete.The application of permeable concrete in water treatment has been studying for more than 30 years.The water treatment technology using water-permeable brick was studied to promote the theoretical and technical progress of water-permeable materials for water treatment,in order to explore new technologies and new water treatment technologies that are environmentally friendly,simple,highly efficient and low-energy consumption.Several different well-type water treatment devices have been designed starting from the side filtration water purification,based on the RC01 sand-based permeable brick with silica sand as the aggregate of surface layer.The effect and technology of water treatment using sand-based permeable brick has been studied,and the influence of sand layer,hydraulic load and running time on the water treatment effect of permeable bricks was analyzed through pilot test and lab test.Blockage process of sand-based permeable bricks was studied and influence of several factors was analyzed through lab test.A new method for measuring the permeability coefficient was developed according to calculus,which can be applied to calculating the permeability coefficient of vertical side-filter permeable device or structure.The results of water treatment test of sand-based permeable bricks show that the sand-based permeable brick has strong resistance to impact load of water quality,which pollution loads has little effect on the removal efficiency.There is little difference in water treatment efficiency of sand-base permeable brick on effluent sewage and sewage after fine screens.The removal rates of COD,TP,TN,NH₄⁺-N and SS in sewage effluent are separately 15%⁵0%,25%⁹0%,3%¹5%,10%³0%,25%⁶0%.The removal efficiency of COD,TP and SS is good,which the average removal rate are 30%,50%,40%separately.The removal rate of several index decrease when hydraulic load increase,and influence extent is COD>NH₄⁺-N>TP>TN.The water treatment efficiency improve with the extension of running time,and influence extent of each finger is TP>COD>SS>NH₄⁺-N>TN.Water treatment of water-permeable brick is comprehensive result of physical interception and filtration,physical adsorption,cross adsorption,chemical adsorption and adsorption biodegradation.Sand-based permeable brick mainly relies on interception,filtration and adsorption to remove pollutants in this test,and the removal efficiency of suspended particulate pollutants is better than dissolved pollutants.The results of blockage test of sand-based permeable bricks show that the clogging process consists of three stages.The process lines can be divided into three types according to the second stage,which are small blockage recovery,medium-speed blockage,and fluctuant blockage respectively.The first stage is rapid blockage and third stages are slow blockages.Permeability coefficient and test time show logarithmic function relationship of which equation form is[y=-aln?x?+b]after normalization and fitting,where 0.096?a?0.157,0.6288?b?8120,and slope of the fitted curve-a/x is the change rate of the permeability coefficient.The larger the initial permeability coefficient,the faster the blockage process and the earlier each stage of the clogging process.The larger the influent SS concentration,the faster the clogging process,the greater the final clogging extent,and the shorter the time required for the blockage process reaching stability.The lower the water level,the faster the first stage of clogging blockage process.