油菜秸秆生物炭强化好氧活性污泥体系污水脱氮效能研究

tudy on the Efficacy of Rape Straw Biochar-enhanced Aerobic Activated Sludge Systems for Wastewater Nitrogen Removal

为提高好氧活性污泥体系的污水脱氮效能,向序批式反应器内分别投加300,500,700℃条件下热解制备的油菜秸秆生物炭(RBC_(300)、RBC_(500)、RBC_(700)),并考察其强化脱氮效果。结果表明,当RBC_(700)投加量为1.0 g/L时,好氧活性污泥体系的平均NH_(4)^(+)-N、TN去除率分别为95.1%、84.5%,比未投加RBC_(700)时分别提升了19.2,51.8个百分点。RBC_(700)对NH_(4)^(+)-N的吸附量分别是RBC_(300)、RBC_(500)的1.8,1.3倍,载膜量分别是RBC_(300)、RBC_(500)的4.5,1.9倍,为同步硝化反硝化的发生创造了有利条件,因而投加RBC_(700)的好氧活性污泥体系可在更短的时间内获得更高的脱氮效率和更好的污泥沉降性能。因此,700℃条件下热解制备的油菜秸秆生物炭应用于好氧活性污泥体系强化脱氮具有良好的可行性。

To improve the wastewater nitrogen removal efficiency of the aerobic activated sludge system,rape straw biochars(RBC_(300)、RBC_(500)、RBC_(700))prepared by pyrolysis at 300,500 and 700℃were added to the sequencing batch reactors and their enhanced effect on nitrogen removal was investigated.The results show that when RBC_(700) dosage is 1.0 g/L,the mean NH+4-N and TN removal rates of the aerobic activated sludge system can reach 95.1%and 84.5%,respectively,which are 19.2 and 51.8 percentage points higher than those without RBC adding.RBC_(700) adsorbs 1.8 and 1.3 times more NH_(4)^(+)-N than RBC_(300) and RBC_(500),respectively,and can carry 4.5 and 1.9 times more biofilm than RBC_(300) and RBC_(500),respectively.These create favourable conditions for the occurrence of simultaneous nitrification and denitrification,thus the aerobic activated sludge system with RBC_(700) adding can obtain higher nitrogen removal efficiency and better sludge settling performance in a shorter time.Hence,the application of rape straw biochar generated by pyrolysis at 700℃ for enhancing nitrogen removal efficiency in the aerobic activated sludge system is of good feasibility.