Research On Mechanisms And Application Of Smaip On Villages And Towns Sewage Treatment

The level of economic and technological is relatively low in our country, andDeveloping low investment cost, high efficiency, simple maintenance processaccording to the local conditions is a key link in our village sewage treatment. Ourresearch group carried enhanced means experiment on traditional natural ecologicalpurification system based on the towns and villages sewage characteristics, duringwhich, static tests, natural field ecological experiment, and industrialized-assistedbiological mode of operation were applied respectively. Our researches strengthenedthe means of suspended mobile artificial aeration, artificial floating island andimmobilized biological carrier, together with the ultra anaerobic digestion in theexperiment, developed the Suspended Mobile Aeration Integrated Process (short asSMAIP) , and preliminary study and research its properties and mechanism. The mainconcussions of the paper are as follow:The SMAIP system is simple cultured and fast started, professionals are notnecessary in the starting period.Suspended mobile aeration applies a microporousmembrane, which is better than the artificial aeration. Dissolved oxygen can be easilycontrolled. The purifying effect of suspended mobile aeration on COD_Cr,NH3-N,TP issignificant, the removal efficiency reaches over 81%, 80%, and 55%, respectively.The purification efficiency was improved by 37.5%, 30% and 12.5% higher than theexperimental samples. During the trial period, the ratio of C/N in the source water istoo low, no significant effect on the TN purification efficiency.The immobilizedbiocarrier has bigger contact surface area and enhanced surface adsorption, containinga large number of nitrifying bacteria, denitrifying bacteria, which accelerates thedegradation of nitrogen. The immobilized biocarrier had significant purifying effecton the removal of COD_Cr, NH3-N,TN and TP, up to 87.69%, 72.65%, 41% and83.98% , respectively. The purification efficiency was improved by 22.15%, 15.33%,8.65% and 34.41%.The purtrification capacity of the artificial floating islands appearconsisitance with the growth characteristics of the aquatic plants. During the trialperiod, the Lythrum grows fastest; aquatic yellow iris has the most luxuriant stemsand leaves. During 4 days stable operation, the Lythrum and aquatic yellow islandshad significant purifying effect on the removal of COD_Cr, NH3-N,TN and TP, up to50%, 50%, 15% and 70%, respectively. Reed floating islands grew downward with less fibrous roots. During the trial period, the adsorption capacity was weak, and theremoval of COD_Cr, NH3-N,TN and TP, up to 50%, 20%, 6% and 45%, respectively.SMAIP system apply the natural ecological non-powered mode or theindustrialized biological mode on different season, water temperature, llluminationand different growing season of the aquatic plants.In the natural ecological non-powered mode, the average purification efficiencyof COD_Cr, NH3-N,TN and TP was 60.89%, 31.20%,19.7% and 21%, respectively. Thecorrelation coefficient between the purification efficiency and the water temperaturewas 0.6928, 0.8544, 0.6796 and 0.8519, respectively, and the correlation coefficientbetween the purification efficiency and the HRT was 0.8975, 0.8558, 0.5372, and0.9023, respectively. the SMAIP system consistent with total mixed CSTR model.Using Arrhenius law to describes the relationship of temperature on reaction rate, themathematical model formula was derived as: Ce=C0(1+1.38×1.23(T-20)×Tm). Thecorrelation coefficient between the measured values and calculated values was0.7814.Supplemented by the industrialized biological mode, the system purificationefficiency of COD_Cr,NH3-N,TN and TP was significantly improved till 90.28%,92.78%, 60% and 52.43%, respectively. For most of the time the effluent waterquality was lower than 1A emissions standard (GB1898-2002). The correlationcoefficient between the purification efficiency and the water temperature is lower, thephosphorus removal under lower temperature was relatively better than that in highertemperature. SMAIP system use of microbial utilization of organic substrate, theMonod kinetic model was applied to describe the biochemical degradation processand the mathematical model was derived formula as: S STOe. .X.The correlation coefficient between the measured values and calculated values was0.9553.In the case of large village with population of 1000, the investment of SMAIPsystem is about RMB 150,000 yuan, covers an area of 600m2, the operating cost is6620 yuan per year and the total installed capacity is 1.5kw.