Study On The Key Technologies Of MaiFan Stone Mineralizing Direct Drinking Water Using Water Circulation

The quality of drinking water is very important to human health.In order to solve the problems of bacteria,nitrite and mineral elements losing of water purifier,the water circulation and MaiFan Stone were innovatively used to drinking water treatment and set up a direct drinking water system using water circulation MFS mineralizaton and water purification.Firstly,we examined the impact and principle of water circulation on water quality,secondly,systematically discussed the characteristic and mechanism of MFS mineralization of drinking water at water circulation,established the mineralization mode of MFS,the purification performance of MFS under cyclic mineralization condition to.disinfection by-products like trihalomethanes in drinking water was investigated too.Finally,we analyzed the effluent water quality of direct drinking water system and estimated the investment and running cost of the system.The main conclusions were:(1)Water cycle could inhibit the growth of 50% or more of nitrite in water,and the removal efficiency of organic compounds was 20%~90%,while inhibiting the breeding of microorganisms.(2)Using the total dissolved solids(TDS)of MFS as the indicators of dissolution performance.The diameter of 1-3 mm had the best performance of continuous dissolution at48 W power,pH 7,dissolution 3 h,the TDS reduced to 1/2 of initial after dissolution ten times.The single factor experimental results showed that the MFS dissolution increased with the grows of solid-liquid ratio;pump power in 48 W has the best dissolution;TDS increased and then be stable and then increased too at a continuous dissolution;it was benefit for dissolution at pH 6~7,while there was less affected at partial acid or alkaline;when the hardness increased,there was less influence to metasilicic acid but could induced the dissolution of Sr,the overall analysis was that MFS is suitable for the mineralization at different pH and hardness of drinking water.(3)Factors which influencing MFS dissolution had the role of solid-liquid ratio >dissolution times > initial pH through the Response surface method(RSM)analysis,which also set up the MFS dissolution models of different single dissolution time.those modlescould provide parameter selection reference for the conditions to achieve water of Sr or metasilicic acid type were different at different single dissolution time.(4)MFS had a purification efficiency to THMs when mineralization,the efficiency in THMs was TCM>BDCM>DBCM,,the purification efficiency was 69%,66%,63%,after running 48 h and the efficiency decreased with the increase of molecular weight of organic matter.(5)We chose activated carbon materials from Gaoshida,hot cathode UV sterilization lamp,MFS liquid ratio of 1:3,48 w pump power,single dissolution time 3 h,the effluent quality can reach CJ94-2005 "drinking water quality standards",the cost of the system was about 590~710 per set.