| A series of research on Chemical Enhanced Coagulation and Moving-Bed Biofilm Oxidation (CEPT-MBBR) process at temperature of 24～30°C has been finished with concern of application. To proceed, a study of denitrification and phosphorous removal mechanism as well as sludge yield and performance at temperature of 7～22°C was carried out. To cut the cost, a change of the process and the treatment mechanism of the new process was tried.It shows that, in the CEPT-MBBR system, under temperature of 7～22°C, when the DO of the aeration tank is controlled at 2～3mg.L, the MLSS and attached biomass are 2000～3000mg/L and 600～1200mg/L respectively. Due to the attached increased biomass, the nitrification can be kept at above 0.025kgNH3-N/(kgTS.d), which is better than that of conventional activated sludge process. The efficiencies of nitrification and denitrification decrease apparently with temperature below 10°C. The HRT of the anoxic tank is not long enough and the contribution of coagulation to phosphorus removal changes with temperature. The CST of chemical sludge and residual sludge are both beyond 20s and could be mixed to dewater. The effect of temperature on sludge dewaterability is moderate. The SVI of residual sludge remains below 150mL/g as an index of good settleability.To the integrative MBBR process, at temperature of 25.2 - 31.5°C, with HRT of 5 ～6h, dosage of PAC 30 mg/L, adding ratio of carrier 50%, DO at MBBR1 and MBBR2 of 1～3mg/L and 2.5～6.6mg/L respectively, the attached biomass achieves below 1000mg/L and the effluent concentration of NH3-N fluctuates from 3mg/L to 17mg/L. Increase of nitrite and phosphorous release can be observed as well.When the CEPT-MBBR process is operated at low temperature, an extention of the HRT of anoxic tank to 2 ～2.5h is suggested. As for the integrative MBBR process, a further research on the improvement of nitrification should be carried out.An enhance of the attached biomass should be achieved to both of the two systems.
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