| It is necessary to research the wastewater treatment technology, which is low construction costs, low operation and maintenance costs, on the situation of the serious water pollution and the relatively fund deficient. The porous concrete eco-films water treatment technology is presented for meeting the request. In this paper, porous concrete eco-films which is made from cement, crushed stones, coal ash and the activated material CRLT-1, are used to treat wastewater in cannel reactor made by ourselves.The effect of start-up characteristic and operation condition on COD and TN removal was investigated. The biomass, SOUR and microorganism distribution was observed. The characteristic of bio-film and capacity of nitrogen removal were analyzed.The start-up of porous concrete eco-film reactor is rapid. Using the way of cycle start-up, formation of bio-film accelerates, and only 15 days is needed to get steady operation.The efficiency of COD and TN removal was studied under different operation condition, using sewage. Operation results for half a year indicated that simultaneous nitrification and denitrification (SND) can be observed in reactor, and the reactor has operated steadily, suggesting that reactor has capacity to suit shock loadings. Under the condition of resident time of 2.5h, organic load of 1.04～3.01kg COD/(m3·d), C/N ratio of 4.0～9.5 and concentration of low DO (DO concentration about 1.5mg/L in entry), removal efficiency of COD, NH4+-N and TN reach 76%, 66% and 33%, respectively. C/N ratio has an obvious influence on simultaneous nitrification and denitrification. Nitrification efficiency is increased slowly, then decreased evidently, during the treatment of sewage. When C/N ratio is 7.7, removal efficiency of TN is the highest, up to 38%. The DO distribution is non-uniformity in the reactor. Under certain flux, DO concentration reduces gradually along the direction of length and depth, resulting in that upper water is aerobic, middle is anoxic, bottom is anaerobic. The value of pH decreases slightly along with the direction of length. In the reactor there are abundant Protozoan and Metazoan which established a long food chain. Biomass and SOUR decrease obvious, and biomass and SOUR on biofilm are 3.16～10.72mg/cm2 and 8.32～14.59mgO2/g·h, respectively, along with the direction of reactor length. Due to different interior microenvironment, the SND phenomenon occurred in different regions of the reactor. The amount of Nitrobacteria and Nitrosomonas decrease obviously in the tail of the reactor.According to the principle of environmental microbiology, combined with experimental results, kinetics equations for degradation of organic pollutants and NH4+-N were deduced as following: S=S0exp(-17.8 A/QS0-0.15 L) and S=S0exp(-7.61 A/QS00.11 L)The study discussed the react mechanism and kinetics of porous concrete eco-film reactor, provided a base of engineering application and is of important significance, for sewage treatment.
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