Research On The Assessment Of Energy And Environmental Benefits Of Waste–to-energy In China

With the increase of population and the improvement of living standard,China is facing the problems of resource exhaustion,increasing energy demand,and the increase of greenhouse gas?GHG?emissions and waste generation caused by energy consumption.Waste as a kind of biomass is an important part of renewable energy,can be used for energy recovery through incineration,anaerobic fermentation and other ways.Waste–to-energy can not only reduce the impacts on the environment caused by GHG and pollutant emissions,but also improve the efficiency of waste resource utilization.In this paper,based on the theory of circular economy,to carry out the simulation of waste–to-energy potentials and emission mitigation effects in the future,we discussed the energy and environmental benefits of urban waste–to-energy from the perspective of cities and provinces in China.Finally,we propose policy recommendations of waste–to-energy in regions and provide decision-making reference for scientific waste management.We focus on modeling and applications related to the wastes generation,energy utilization potential and GHG and pollutant emission mitigation potentials in order to extend and improve research thinking and model methods in the field of energy and environment benefits of waste-to-energy accounting physical input-output?PIO?model at both city and provincial levels,based on the monetary input-output?MIO?model.We make up for the inadequacy and lack of assessment of the energy and environment benefits of waste-to-energy.First of all,the wastes can be divided into four types:combustible waste,food waste,high concentration organic wastewater and breeding-farm manure.Based on monetary input-output table,according to the direct consumption coefficients in the MIO model and physical output,the monetary quantity is converted into physical quantity.Based on the classification of the traditional sectors,waste power generation sectors will be introduced into the current socioeconomic system,including combustible waster power generation sector,food waste biogas power generation sector,high concentration organic wastewater biogas power generation sector,breeding-farm manure biogas power generation sector,to establish a physical input-output model for accounting the energy and environment benefits of waste-to-energy.Secondly,we establish corresponding relationships between waste generation and traditional sectors to quantitatively analyze the waste-to-energy efficiency.Moreover the clean development mechanism?CDM?is combined with the PIO model for the quantitative analysis of environmental benefits of waste-to-energy.An evaluation system of energy and environment benefits of waste-to-energy in China is constructed.We construct a physical input-output model for accounting the urban energy and environmental benefits of waste-to-energyat city level,taking Changchun city as an example.The 42 sectors in the MIO table are merged into 15 ones and with the introduction of four waste power generation sectors as 19 sectors in the physical input-output model.We quantitatively explore the energy and environment benefits of waste-to-energy in Changchun city.According to the results,from 2016 to 2025,the generation amount of four wastes in Changchun is increasing year by year,with the cumulative emission mitigation amount as 84 million tons of carbon dioxide equivalent?CO₂-e?GHG,0.16 million tons of SO₂ and 0.29 million tons of NO_x,making a certain contribution to the energy conservation and emission mitigation in Changchun city.Based on the physical input-output model for accounting the energy and environmental benefits of waste-to-energy at city level,as provincial level data is more abundant,the 42 sectors in the MIO model is merged into 24 ones,with the addition of four waste power generation sectors as 28 sectors,to construct the physical input-output model for accounting the energy and environmental benefits of waste-to-energy at provincial level.The results show that:?1?From 2016 to 2025,among the 31 provincial level regions in China,the cumulative generation of combustible waste and food waste in Guangdong is the largest,reaching 115 million tons and 89 million tons respectively;the cumulative generation of highly concentrated organic wastewater in Hebei is the largest,reaching 3.724 billion tons;and the cumulative generation of breeding-farm manure in Sichuan is the largest,reaching 115 million tons.Guangdong and Jiangsu generate 109.562 billion kWh and 98.703 billion kWh from 2016 to 2025 as coastal areas.The regions in the northwest China,such as Ningxia and Tibet,have generate less power.?2?From 2016 to 2025,the GHG emission mitigation in Hebei compared with the baseline is 520 million tons CO₂-e,followed by 438 million tons CO₂-e in Guangdong and 437 million tons CO₂-e in Jiangsu.After the change of industrial structure,the cumulative mitigation emission potentials for GHG,SO₂,NO_x and soot and dust in Hebei is the highest,with the mitigation as 61.13 million tons CO₂-e,1.84million tons,9.16 million tons and 16.67 million tons,followed by Guangdong and Zhejiang.The northwestern regions including Qinghai,Ningxia and Tibet have less GHG and air pollutants emissions mitigation.At the same time,it is identified that the traditional sectors have a great impact on the GHG and air pollutants emissions mitigation.The study found that among the traditional 24 sectors,the energy utilization sectors,such as production and supply of power and heat,coal extraction and selection,oil and natural gas extraction sectors have the greatest impacts on the GHG and air pollutants emissions mitigation in China.Based on the the quantitative research results energy and environmental benefits at provincial level,clustering analysis is further conducted.The analysis results show that waste energy efficiency and environmental benefits have consistency in China,most of the regions energy and environmental benefits of waste-to-energy are poor,only the coastal areas in Hebei,Jiangsu,Shandong,Guangdong and Zhejiang have better energy and environmental benefits.Therefore according to the above evaluation results as well as the advantages and development potential of waste power generation sector in China,31 provincial regions in China could be divided into three groups:coastal developed areas,the rapid development regions and less developed areas.According to the spatial differences in the energy and environmental benefits of waste-to-energy in above three areas,suggestions of waste management are proposed respectively.The coastal developed areas should further improve the level of waste power generation technologies and accelerate industrial upgrading and transformation.The rapid development regions should improve waste collection and storage systems and establish carbon trading markets as soon as possible.The less developed areas should continue to accelerate economic development and increase government subsidies.