| Land treatment system is an effective way in bettering environment and easing present water shortage problem, for its low cost,low investment,nice wastewater treatment result and practicability of reclaiming treated water. However, its popularization are greatly limited by two points: the blockage and recovery of Filtration medium, which are key for the system's stable after long time's run. So, based on traditional land treatment systems, a new method was advanced to use capillary phenomenon existing in porous medium to filtrate domestic wastewater in this paper. The oxidation-reduction mechanism was studied, and the effect of temperature on system oxidation-reduction environment,wastewater treatment rate and pollutant removal efficiency were analyzed, by using the experiments of treating domestic wastewater in Reversed Filtration System(RFS) under three different temperatures: 5℃,ambient temperature(25℃-30℃) and 35℃.The experimental results showed that the OxidationReduction Potential(ORP) changed obviously at a short distance from pollution source and showed low-high value with the alternation of flooding and drying, which meant the successive anaerobic and aerobic condition in system; ORP negatively related to temperature and influent concentration; The wastewater filtration rate, opposite to the stability of COD removal, was much higher for higher temperature, with the representation of that system under 5℃had the lowest filtration rate but the highest system stability, opposite to system under 35℃; The effluent and total treatment result at 5℃was better than at 35℃and less than at 25℃-30℃. The relationship between COD and influent concentration C0 can be approximated as a parabola and the remove rate achieves largest at C0=269,294 and 286mg/L as experimental temperatures are 5℃, 25-30℃and 35℃respectively. One-order temperature degradation model can be used well to describe the dynamic processes of COD degradation and degradation rate KT increases exponentially with temperature.
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