Study On Carbon Emission Of Urban Domestic Wastewater Treatment System

In recent years,climate change has been remarkable.Extreme weather has occurred from time to time and the problem of global warming has attracted the attention of all countries in the world.Urban domestic sewage treatment system is one of the important sources of GHG contribution.However,carbon emission research about this source of contribution has been neglected and there is no estimation and analysis of systematic and accurate.This article describes the research object of the urban sewage treatment system.Use of the methane emission factor obtained from the actual measurement method to improve the recommendations in the "IPCC GHG Inventory Guidelines "and obtains other emission factors through the IPCC.Refer to the relevant literature obtains the calculation of sludge.Improved the accounting methods for indirect carbon dioxide emissions,comprehensived utilization of domestic sewage sludge for building materials and land use that the carbon emission accounting system for urban domestic wastewater treatment systems is given to estimate carbon emissions from urban sewage treatment systems in Jiangsu Province in 2020.According to the foregoing,prediction models is proposed.Finally,the strategy of low-carbon operation of the urban sewage treatment system in Jiangsu Province was discussed.The study found that the total carbon emissions of urban domestic wastewater in Jiangsu Province in 2015 was 801,400 tons which CH4 emission was 15,200 tons,N20 emission was 0.25 million tons and CO2 emission indirectly was 783,700 tons.CO2 equivalent represented carbon emissions that the total amount was 1,864,100 tons,the CH4 emission CO2 equivalent was 426,100 tons,the N2O emission CO2 equivalent was 654,200 tons and the CO2 emission indirectly was 783,700 tons.In terms of GHG and CO2 equivalent that CO2 emission indirectly was the main contributor.From 2010 to 2015,the total carbon emissions from various urban greenhouse gas emissions in Jiangsu Province reached 4,401,800 tons that expressed as CO2 equivalent of the total carbon emissions were 10,753,300 tons.The major contributor to the carbon emissions from urban domestic sewage treatment in Jiangsu Province during 2010-2015 was CO2 emission indirectly accounting for 96.82%,followed by CH4 emission accounting for 2.83%and at least N2O emission accounting for 0.35%.The average carbon emission level was 0.1818 kg GHG/t sewage(CO2 equivalent discharge 0.4960 kg CO2/t sewage).The total carbon emissions from sludge treatment in Jiangsu Province in 2015 was 1,529,300 tons,which sludge incineration accounted for 1,139,600 million tons,which the sludge land use treatment method which accounted for 1,200 million tons.From 2009 to 2015,the amount of carbon emissions from sludge treatment in Jiangsu Province were 7,883,500 tons that CO2 equivalent was 14,768,500 tons that the average annual growth rate was 16.57%that the average carbon emission level of urban sludge was 0.42489 t GHG/t sludge(CO2 equivalent carbon emission level was 0.82082 t CO2/t sludge).The carbon emission levels of five treatment methods for domestic sludge that the burning is high and the land use is low.It is estimated that the carbon emissions from sewage and sludge treatment in Jiangsu Province in 2020 will reach respectively 896,500 tons and 1,798,800 tons(a total of 2,695,300 tons)that CO2 equivalent will reach respectively 2,445,800 tons and 3,369,800 tons(a total of 5,815,600 tons).