基于“水-能-碳”关联的城镇污水厂碳排放特性研究

Study on the Carbon Emission Characteristics of Urban Wastewater Plants Based on the "Water-Energy-Carbon" Nexus

污水处理过程产生大量温室气体,在“双碳”战略实施的背景下,开展污水厂运行阶段碳排放核算体系构建及碳排放因素研究具有重要意义。本文以某0.2×10^(4)t/d城镇污水厂为研究对象,基于“水-能-碳”关联系统构建了污水厂碳排放核算体系,并以污水COD去除率、TN去除率、SS去除率、进水碳氮比、进水碳磷比为影响因素,探析了不同工况对碳排放量的影响。结果表明,污水厂日均碳排放量达18 682.81 kg CO_(2),污水COD去除率、TN去除率、SS去除率均与碳排放量呈正向弱相关,而进水碳氮比、进水碳磷比与碳排放量呈负向弱相关。“水-能-碳”关联系统视角下的碳排放核算体系能够较好识别污水厂运行阶段碳排放动态变化规律,为污水厂的节能减排提供科学的依据。

Sewage treatment processes generate significant amounts of greenhouse gases,in the context of the implementation of the'double carbon'strategy,it is of great significance to carry out the construction of the carbon emission accounting system in the operation stage of sewage plants and the study of carbon emission factors.This paper takes a 0.2×10^(4) t/d urban wastewater plant as the research object,constructs the carbon emission accounting system of wastewater plant based on the'water-energy-carbon'correlation system,and analyses the impacts of different working conditions on the carbon emission with the influences of the wastewater COD removal rate,TN removal rate,SS removal rate,influent water C/N,influent water C/P as the impact factors.The results showed that the average daily carbon emission of the wastewater plant reached 18682.81 kgCO_(2),and the COD removal rate,TN removal rate and SS removal rate of the wastewater were positively and weakly correlated with the carbon emission,while the influent C/N and influent C/P were negatively and weakly correlated with the carbon emission.The carbon emission accounting system under the perspective of'water-energy-carbon'correlation system can better identify the dynamic change law of carbon emission during the operation stage of wastewater plants,and provide a scientific basis for energy saving and emission reduction of wastewater plants.