不同填料对地下渗滤系统脱氮效果的影响

Effect of Different Fillers on Denitrification Effect of Subsurface Wastewater Infiltration System

为改善地下渗滤系统(SWIS)脱氮效果,以煤渣和生物基质为填料,构建了1#、2#、3#3套装置,研究水力负荷对地下渗滤系统脱氮效果的影响.结果表明,当水力负荷为10cm/d时,1#装置对NH4+-N、TN平均去除率分别为92.78%>54.77%,但当水力负荷为20cm/d时装置因渗透性较差无法正常运行.2#、3#装置分别在水力负荷为10、20cm/d下运行时,对NH4+-N平均去除率分别下降了24.26个和14.57个百分点,对TN平均去除率分别下降了13.37个和8.13个百分点;TN的去除率变化较大,但其脱氮能力有所提高.2#装置脱氮效果最好.适当添加生物基质可有利于TN的去除,并保持着良好的渗透性能.因此,为保证改良的SWIS在水力负荷为20cm/d下正常长期运行,则与渗透性能较好的煤渣配比时生物基质的量应保持适当的比例.

In order to improve the nitrogen removal effect of surface wastewater infiltration system, three sets of improved units of 1", 2# and 3* were constructed with cinder and biological matrix to study on the effect of fillers on nitrogen removal of subsurface wastewater infiltration system under different hydraulic loads. The results showed that the average removal rates of NH4+-N,TN in the 1 # device were 92.78%, 54.#77% respectively, when the hydraulic load was 10 cm/d. But permeability of the set was poor when the hydraulic load was 20 cm/d, led to it could not work normally. While two devices of 2# and 3# were operated at hydraulic loads of 10 and 20 cm/d, the average removal rate of NH4+-N were decreased by 24.26 and 14.57 percent point, and the average removal rate of TN decreased by 13.37 and 8.13 percent point respectively. The removal rate of TN varied greatly, but the denitrification capacity had improved. The 2# set had the best nitrogen removal effect. Appropriate addition of the biological matrix, it could facilitate the removal of TN and maintain good permeability. Therefore, in order to ensure improved SWIS that has a normal long-term operation under a hydraulic load of 20 cm/d, the amount of biological matrix should be kept in an appropriate ratio when it is matched with cinder with better permeability.