采用改良A^(2)O工艺中型城镇污水处理厂碳排放特征研究

Research on Characteristics of Carbon Emissions in Medium-sized Urban Sewage Treatment Plants Using Improved A^(2)O Processes

运用碳排放因子法,对汕头市4座处理规模相似但A^(2)O工艺各异的中型污水处理厂进行碳排放总量核算与碳排放强度分析。结果表明,采用不同A^(2)O工艺的污水处理厂总碳排放量存在差异,4座污水处理厂总碳排放强度范围为0.317~0.402 kg/m^(3)(CO_(2)-eq)。按处理工艺碳排放从小到大顺序为:多段AO、A^(2)O+厌氧/缺氧调节池、传统A^(2)O、A^(2)O+微曝气氧化沟。但不同处理工艺的碳排放类别组成相似,电力消耗为最主要的碳排放源。与传统的A^(2)O工艺相比,3种改良A^(2)O工艺在减小药耗、CH4排放、N2O排放和污泥处置碳排放源排放强度存在优势,其中多段AO工艺减小总碳排强度的优势最大,据此针对改良A^(2)O工艺的运行碳排优化提出建议。

The carbon-emission-factor approach was used to conduct the total carbon emissions and carbon emis⁃sion intensity of 4 medium-sized sewage treatment plants with similar scale but different A^(2)O processes in Shantou.The results show that the total carbon emissions with different A^(2)O processes are different.The total carbon emission intensity of the 4 sewage treatment plants ranged from 0.317 to 0.402 kg/m^(3)(CO_(2)-eq).The carbon emissions in or⁃der from smallest to largest based on the processing are:multi-stage AO,A^(2)O+anaerobic/hypoxia regulating tank,traditional A^(2)O,A^(2)O+micro-aeration oxidation ditch.However,the carbon emission categories of different proces⁃ses are similar,and electricity consumption is the most important carbon emission source for each process.Com⁃pared with the traditional A^(2)O process,the other three improved A^(2)O processes have advantages in reducing carbon emission intensity of chemicals consumption,CH4 emission,N2O emission and sludge disposal.And the multistage AO process shows the greatest ability to reduce the total carbon intensity.Based on the above results,some suggestions for the carbon emission optimization of the improved A^(2)O processes were put forward.