Current Status And Mitigation Potential Analysis Of Atmospheric Emissions From Coal-Fired Plants In Shandong Province

Severe regional atmospheric pollution was caused by coal-based electricity supply structure and large consumption of coal in Shandong province. Establishment of emission inventory of air pollutants and study on environmental impact quantization in coal-fired power plants throughout the province are conducive to recognition of emission characteristics and legislation of pollution control.Based on unit-based activity data and latest emission factors, a high resolution atmospheric emission inventory for the year of 2002 and 2012 was established in this paper. The mitigation potential of coal-fired power plants in 2020, 2025 and 2030 was predicted by scenario analysis.The environmental effects caused by coal-fired power plants in Shandong province were conducted by local impact assessment model. The main contents of this paper are as following:The emission load of coal-fired power plants in 2002 and 2012 throughout the province was estimated by comprehensive consideration of local coal quality, unit capacity and pollution control technology. The results showed that the emissions level of SO₂ and TSP decreased by 37.15% and 13.54% from 2002 to 2012, respectively,while the emissions level of NOx which overpassed that of SO2 increased 135.22%and became the most challengeable problem in atmospheric pollution control of coal-fired power plants. Although strict pollution control technologies have been taken, the emissions level of PM2.5, Hg, greenhouse gases（CO₂, CH₄ and N2_O）, CO,NMVOCs and NH3 also presented raising trend due to the growing scale of power generation. According to the analysis of unit contribution, the major contributor was the unit（≥300 MW）. The analysis of city contribution showed that Jining, Dezhou and Liaocheng were major contributors. The southwestern region in Shandong was found to have the highest emission intensity and density of air pollutants from units, while some individual point sources in eastern cities also had high emissions. The emissions from coal-fired power plants in the second half of the year were slightly higher than that in the first half year, and the emissions on weekdays were higher than that at weekends. The emissions from coal-fired power plants from 9 am to 5 pm werehighest through the day.Compared with similar inventories, the inventory established in this paper contained more pollutants. The relative estimation of emissions were a little higher than the statistical results due to the adoption of more detailed emission factors and unit information, which was more credible. The emissions from coal-fired units（≥100MW） have lower uncertainty than that of units（<100 MW） as the basic information of each unit（≥100 MW） was considered.To explore the emission control emphasis, business as usual scenario（BAU）,best available control technology scenario（BACT） and high efficiency control technology scenario（HECT） based on the data of the year 2012 were developed to predict the mitigation potential of coal-fired power sector of Shandong. Though the abatement potential of SO₂ emission is relatively limited in the BACT scenario, about60% reduction of SO₂ emission would be achieved in the HECT scenario in 2030 through the increased efficiency of Wet-FGD. NOx emission has greater mitigation potential, and the HECT scenario could result in a NOx emission reduction of about80% at the end of 2030. Emission reductions of about 50% PM2.5 and 60% Hg could be achieved by 2030 in HECT scenario, which are still smaller than that of TSP（77%）.In HECT scenario, the emission level of NH3 is about 12 times the based level by2030, which could be attributed to the development of denitration technology.The evaluation of environmental impacts of pollutants from coal-fired power plants in Shandong conducted by impact assessment model showed that the total weighted environmental impact evaluation of pollutants decreased from 2.9060×10^-3in 2002 to 2.7896×10^-3 in 2012. The impacts of acidification and dust had the most significant downtrend（68% and 70%, respectively）. The weighted environmental impact evaluation of units（≥100 MW, but<300 MW） was the highest, followed by units（<100 MW） and units（≥300 MW）. The environmental impacts of acidification,eutrophication and dust would decline while the rate of contribution of photochemical smog would continue to rise in HECT scenario by 2030.