Research On The Treatment Technics For Lightly Polluted Raw Water By PAC-MF Process And Microbia Characteristic

The drinking water resource is being deteriorated worse, the traditional treatment process can not effectively remove the organic micro pollutants, ammonia, DDV, THMFP, nitrobenzene and so on in the drinking water. The new"Urban water supply quality standard"has been implemented since June 1st, 2005, which has more strict requirement of its items'limit. It increases some detective items of pesticide, organic pollution and the outgrowth of disinfection. The treatment water can not meet the demand of security and the water quality standard. Therefore, the novel water treatment technology has to be developed.This thesis proposed the hybrid process adding Powered Actinated Carbon (PAC) to MF system as the treatment for micro-pollunant water. The removal rate for the UV₂₅₄ by membrane treatment alone is 30%, the removal rate for the permanganate by membrane treatment alone is 23%, the removal rate for the TOC by membrane treatment alone is 20%. So MF or UF is the suitable application for water in which organic matters concentration are not high.The addition of PAC could significantly improve permanganate,UV₂₅₄,TOC,removal. When HRT is 3 hours, the permanganate,UV₂₅₄,TOC removals of PAC—MF combined process are 73.49%-78.78%,57.12%-68.47,78.87%-87.69%. The ammonia and nitrite removals are 98.06%-98.72%,93.75%-99.90%.The average removal efficiency of TN is 34.96%, but in the test it is founded that the nitrate nitrogen concentration of the effluent is lager than that of influent. The removal rate of DDV,THMFP,nitrobenzene are 99.28%,75.26%å’Œ97.51%.We study the removal effect of pollutants by PAC—MF combined process when HRT is one hour,two hours,three hours. It is found that the permanganate,UV₂₅₄,TOC,ammonia and nitrite removals of PAC—MF combined process are increased with the increaseof the HRT. When HRT is one hour which is small, the permanganate of effluent is always below 2.5mg/L, the TOC of effluent is always below 4mg/L, the UV₂₅₄ removal efficiency is 72.50%-82.52%, the ammonia removal efficiency is always more than 90%, the effluent satisfy the need of the"Urban water supply quality standard". The nitrite...