The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The enviro...The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The environmental management of hazardous waste in coal-fired power plants started late, and there are many problems in the construction and management of their storage facilities. In this paper, taking eight typical coal-fired power plants as examples, the present problems of hazardous waste storage facilities in coal-fired power plants are analyzed, and corresponding countermeasures are put forward to solve the main common problems.展开更多
In China, according to the relative up-to-date regulations and standards, the maincontrol measure for NOX emission of coal-fired power plants is, in principle, low NOXcombustion. However, in recent years, more and mor...In China, according to the relative up-to-date regulations and standards, the maincontrol measure for NOX emission of coal-fired power plants is, in principle, low NOXcombustion. However, in recent years, more and more newlyapproved coal-fired plantswere required to install flue gas denitrification equipment. This article expounds if fluegas denitrification is necessary from several aspects, including constitution of NOX, itsimpact to environment, operation ofdeNOXequipment in USA, as wellas the differencein ambient air quality standard between China and World Health Organization. It setsforth themes in urgent need of study and areas where deNOX equipment is necessaryfor new projects, besides a recommendation that the emission standards for thermalpowerplants should be revised as soon as possible in China.展开更多
Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power plants.However,the effects of coal-fired power...Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power plants.However,the effects of coal-fired power plants on soil microbial communities have received little attention through atmospheric pollutant deposition and coal-stacking.Here,we collected the samples of power plant soils(PS),coal-stacking soils(CSS)and agricultural soils(AS)around three coal-fired power plants and background control soils(BG)in Huainan,a typical mineral resource-based city in East China,and investigated the microbial diversity and community structures through a high-throughput sequencing technique.Coal-stacking significantly increased(p<0.05)the contents of total carbon,total nitrogen,total sulfur and Mo in the soils,whereas the deposition of atmospheric pollutants enhanced the levels of V,Cu,Zn and Pb.Proteobacteria,Actinobacteria,Thaumarchaeota,Thermoplasmata,Ascomycota and Basidiomycota were the dominant taxa in all soils.The bacterial community showed significant differences(p<0.05)among PS,CSS,AS and BG,whereas archaeal and fungal communities showed significant differences(p<0.01)according to soil samples around three coal-fired power plants.The predominant environmental variables affecting soil bacterial,archaeal and fungal communities were Mo-TN-TS,Cu-V-Mo,and organic matter(OM)-Mo,respectively.Certain soil microbial genera were closely related to multiple key factors associated with stacking coal and heavy metal deposition from power plants.This study provided useful insight into better understanding of the relationships between soil microbial communities and long-term disturbances from coal-fired power plants.展开更多
The United States is one of the world’s leaders in electricity production,generating about 4116 billion kWh in 2021,of which coal accounted for 21.8%of the total.This study applies an integrated approach using both t...The United States is one of the world’s leaders in electricity production,generating about 4116 billion kWh in 2021,of which coal accounted for 21.8%of the total.This study applies an integrated approach using both terrestrial and satellite data to specifically examine emissions from coal-fired power plants and its spatial extent.The study also highlights the effectiveness of government policies to reduce emissions.It was found that emission of pollutants from the country’s energy sector has been steadily declining,with annual emissions of sulfur dioxide(SO_(2))and nitrogen oxides(NOx)decreasing from the US electric power sector between 1990 and 2020 by 93.4%and 84.8%,respectively,and carbon dioxide(CO_(2))by 37%between 2007 and 2020.Although overall emissions from coal-fired power plants are declining,some individual plants have yet to install environmental equipment to control emissions.According to US government data,major emitters of SO_(2),NO_(x),and CO_(2) in the US are the Martin Lake power plant in East Texas,the Labadie power plant near St.Louis,Missouri,and the James H Miller Jr plant near Birmingham,Alabama.This study also integrates TROPOMI satellite data to detect point emissions from individual power plants.While the highest levels of measured pollutants were over the country’s major cities and areas of fossil fuel extraction,TROPOMI could clearly distinguish the pollution caused by power plants in more rural areas.Although the US has made great strides in reducing emissions from coal-fired power plants,these plants still represent a major source of pollution and remain a major concern.Totally eliminating coal as a power source will be difficult with the higher power demands resulting from the transition to electric automobiles.展开更多
China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)in...China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)including selenium(Se),mercury(Hg),lead(Pb),arsenic(As),etc.,from Coal-Fired Power Plants(CFPPs),which are the major toxic air pollutants causing widespread concern.For this reason,it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions.The study herein reviews various techniques applied in China for the selected HTEs emission control,including the technical,institutional,policy,and regulatory aspects.The specific areas covered in this study include health effects,future coal production and consumption,the current situation of HTEs in Chinese coal,the chemistry of selected HTEs,control techniques,policies,and action plans safeguarding the emission control.The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development.The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China.Future research should focus on the simultaneous removal of HTEs,PM,SOx,and NOx in the complex flue gas.展开更多
To make coal-fired power generation more environmentally friendly,China has initiated a series of ultra-low emission ret-rofits to the air pollution control(APC)system of the existing power plants.In this study,a life...To make coal-fired power generation more environmentally friendly,China has initiated a series of ultra-low emission ret-rofits to the air pollution control(APC)system of the existing power plants.In this study,a life cycle assessment(LCA)is conducted to analyze the environmental net benefits for the typical ultra-low emission retrofit of a 1000 MW power plant.The key processes,substances,and APC devices are verified and discussed.The results confirm that the retrofit effectively decreases the environmental stress of acidification potential(AP),eutrophication potential(EP),and photochemical ozone creation potential(POCP)by 69%-79%,which can be attributed to significantly reduced emissions at the stack.However,the retrofit has also increased other impact categories by 24%-79%,primarily due to the consumption of additional elec-tricity and adsorbents.The retrofit of selective catalytic reduction,electrostatic precipitator(ESP),and wet limestone flue gas desulfurization devices has a dominant effect on the impacts of EP,human toxicity potential(HTP),and AP.A newly installed wet ESP shows some environmental benefits(only for AP),but causes considerable burdens,in particular for the investigated impact categories global warming potential(GWP),marine aquatic ecotoxicity(MAETP),and abiotic depletion fossil(ADP fossil).The obtained results indicate that the hidden environmental consequences,which are associated with the production of energy and materials,need to be examined more comprehensively to inform the development of ultra-low emission technologies and strategies effectively.展开更多
The flue gas pollutants deep-removal technology(DRT) focusing on PM2.5removal is the prime method of further reducing pollutants emission from coal-fired power plants. In view of the four key technological challenges ...The flue gas pollutants deep-removal technology(DRT) focusing on PM2.5removal is the prime method of further reducing pollutants emission from coal-fired power plants. In view of the four key technological challenges in developing the DRT, studies were conducted on a series of purification technologies and the DRT was developed and successfully applied in 660 MW and 1000 MW coal-fired units. This paper analyzes the application results of the demonstration project, and proposes a roadmap for the follow-up researches and optimizations.展开更多
Coal-fired power operators continue to look for ways to increase the efficiency and extend the working lives of their plants by improving operational flexibility and reducing environmental impact.Two possible options ...Coal-fired power operators continue to look for ways to increase the efficiency and extend the working lives of their plants by improving operational flexibility and reducing environmental impact.Two possible options are explored here:combining solar energy with coal-fired power generation,and cofiring natural gas in coal-fired plants.Both techniques show potential.Depending on the individual circumstances,both can increase the flexibility of a power plant whilst reducing its emissions.In some cases,plant costs could also be reduced.Clearly,any solar-based system is limited geographically to locations that receive consistently high levels of solar radiation.Similarly,although many coal-fired plants already burn limited amounts of gas alongside their coal feed,for cofiring at a significant level,a reliable,affordable supply of natural gas is needed.This is not the case everywhere.But for each technology,there are niche and mainstream locations where the criteria can be met.The need for good solar radiation means that the uptake of coal-solar hybrids will be limited.Cofiring natural gas has wider potential:currently,the largest near-term market appears to be for application to existing coal-fired plants in the USA.However,where gas is available and affordable,potential markets also exist in some other countries.展开更多
On-site measurements of volatile organic compounds(VOCs)in different streams of flue gas were carried out on a real coal-fired power plant using sampling bags and SUMMA canisters to collect gas samples,filters to coll...On-site measurements of volatile organic compounds(VOCs)in different streams of flue gas were carried out on a real coal-fired power plant using sampling bags and SUMMA canisters to collect gas samples,filters to collect particle samples.Gas chromatography-flame ionization detector/mass spectrometry and gas chromatography-mass spectrometry was the offline analysis method.We found that the total mass concentration of the tested 102 VOC species at the outlet of wet flue gas desulfuration device was(13456±47)μg·m^(-3),which contained aliphatic hydrocarbons(57.9%),aromatic hydrocarbons(26.8%),halogen-containing species(14.5%),and a small amount of oxygen-containing and nitrogencontaining species.The most abundant species were 1-hexene,n-hexane and 2-methylpentane.The top ten species in terms of mass fraction(with a total mass fraction of 75.3%)were mainly hydrocarbons with a carbon number of 6 or higher and halogenated hydrocarbons with a lower carbon number.The mass concentration of VOC species in the particle phase was significantly lower than that in the gas phase.The change of VOC mass concentrations along the air pollution control devices indicates that conventional pollutant control equipment had a limited effect on VOC reduction.Ozone formation potential calculations showed that aromatic hydrocarbons contributed the highest ozone formation(46.4%)due to their relatively high mass concentrations and MIR(maximum increment reactivity)values.展开更多
In order to reduce the environmental smog caused by coal combustion,air pollution control devices have been widely used in coal-fired power plants,especially of wet flue gas desulfurization(WFGD)and wet electrostatic ...In order to reduce the environmental smog caused by coal combustion,air pollution control devices have been widely used in coal-fired power plants,especially of wet flue gas desulfurization(WFGD)and wet electrostatic precipitator(WESP).In this work,particulate matter with aerodynamic diameter less than 10μm(PM_(10))and sulfur oxides(SO_(x))have been studied in a coal-fired power plant.The plant is equipped with selective catalytic reduction,electrostatic precipitator,WFGD,WESP.The results show that the PM_(10)removal efficiencies in WFGD and WESP are 54.34%and 50.39%,respectively,and the overall removal efficiency is 77.35%.WFGD and WESP have effects on the particle size distribution.After WFGD,the peak of particles shifts from 1.62 to 0.95μm,and the mass concentration of fine particles with aerodynamic diameter less than 0.61μm increases.After WESP,the peak of particle size shifts from 0.95 to 1.61μm.The differences are due to the agglomeration and growth of small particles.The SO_(3)mass concentration increases after SCR,but WFGD has a great influence on SO_(x)with the efficiency of 96.56%.WESP can remove SO_(x),but the efficiency is 20.91%.The final emission factors of SO_(2),SO_(3),PM_(1),PM_(2.5)and PM_(10)are 0.1597,0.0450,0.0154,0.0267 and 0.0215(kg·t^(−1)),respectively.Compared with the research results without ultra-low emission retrofit,the emission factors are reduced by 1~2 orders of magnitude,and the emission control level of air pollutants is greatly improved.展开更多
Xiangfan Coal-fired Power Plant, a key energy construction project matched with Three Gorges Project, approved by the State Council. formally started to build in the suburb of Xiangfan City, Hubei Province on November...Xiangfan Coal-fired Power Plant, a key energy construction project matched with Three Gorges Project, approved by the State Council. formally started to build in the suburb of Xiangfan City, Hubei Province on November 29, 1996.展开更多
On October 21, 2003, the first unit of Taishan PowerPlant-the largest coal-fired power plant plannedcurrently in Asia, was successfully connected to the power grid to generate electricity.
This paper proposed a novel integrated system with solar energy,thermal energy storage(TES),coal-fired power plant(CFPP),and compressed air energy storage(CAES)system to improve the operational flexibility of the CFPP...This paper proposed a novel integrated system with solar energy,thermal energy storage(TES),coal-fired power plant(CFPP),and compressed air energy storage(CAES)system to improve the operational flexibility of the CFPP.A portion of the solar energy is adopted for preheating the boiler’s feedwater,and another portion is stored in the TES for the CAES discharging process.Condensate water from the CFPP condenser is used for cooling compressed air during the CAES charging process.The thermodynamic performance of the integrated system under different load conditions is studied.The system operations in a typical day are simulated with EBSILON software.The system enables daily coal saving of 9.88 t and reduces CO_(2)emission by 27.95 t compared with the original CFPP at 100%load.Under partial load conditions,the system enables maximum coal saving of 10.29 t and maximum CO_(2)emission reduction of 29.11 t at 75%load.The system has maximum peak shaving depth of 9.42%under 40%load condition.The potential of the system participating ancillary service is also discussed.It is found that the integration of solar thermal system and CAES system can bring significant ancillary service revenue to a conventional CFPP.展开更多
This paper takes the specific characteristics of pulverized coal room in thermal power plant as the starting point,firstly,this paper analyzes the process layout and structure selection,and then the structural design ...This paper takes the specific characteristics of pulverized coal room in thermal power plant as the starting point,firstly,this paper analyzes the process layout and structure selection,and then the structural design and vibration design requirements of coal crusher house are introduced in this paper.Finally,based on the engineering example,a new structure form of vibration isolation design is creatively proposed,which provides a new design idea for the practical engineering design.展开更多
Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned par...Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned particulate matter(PM)around the ULE-retrofitted CF-PPs are less understood.Here,total Hg and its chemical speciation in TSP(total suspended particles),PM_(10)(aerodynamic particle diameter≤10μm)and PM_(2.5)(aerodynamic particle diameter≤2.5μm)around a ULE-retrofitted CFPP in Guizhou Province were quantified.Atmospheric PM_(2.5)concentration was higher around this ULE-retrofitted CFPP than that in the intra-regional urban cities,and it had higher mass Hg concentration than other sizefractioned PM.Total Hg concentrations in PM had multifarious sources including CFPP,vehicle exhaust and biomass combustion,while they were significantly higher in autumn and winter than those in other seasons(P<0.05).Regardless of particulate size,atmospheric PM-bound Hg had lower residual fractions(<21%)while higher HCl-soluble fractions(>40%).Mass concentrations of exchangeable,HCl-soluble,elemental,and residual Hg in PM_(2.5)were higher than those in other size-fractioned PM,and were markedly elevated in autumn and winter(P<0.05).In PM_(2.5),HCl-soluble Hg presented a significantly positive relationship with elemental Hg(P<0.05),while residual Hg showed the significantly positive relationships with HCl-soluble Hg and elemental Hg(P<0.01).Overall,these results suggested that atmospheric PM-bound Hg around the ULE-retrofitted CFPP tends to accumulate in finer PM,and has higher bioavailable fractions,while has potential transformation between chemical speciation.展开更多
The cofiring of biomass and coal may be one of the most effective methods to improve energy utilization efficiency and reduce greenhouse gas emissions.This study aims to investigate combustion performance,interaction ...The cofiring of biomass and coal may be one of the most effective methods to improve energy utilization efficiency and reduce greenhouse gas emissions.This study aims to investigate combustion performance,interaction and synergistic effects in the cofiring of coal and three types of biomass.Blended fuel consisting of coal and three types of biomass such as sawdust,rice husk and solid recovery fuel was selected as the research object.Ultimate and proximate analysis and differential thermogravimetric analysis with heating rates of between 10°C and 40°C/minute are used to analyse combustion characteristics.Simulation of combustion in a 600-MWe steam power plant with a Carolina-type boiler is also carried out with the help of computational fluid dynamic(CFD)analysis to see the effect of the interaction and synergy of the mixed fuel on the performance of the steam generator.The effect on the com-bustion process in the combustion chamber of a steam power plant is also simulated.Based on the analysis of several test results of parameters such as ignition temperature,burnout temperature,calorific value of the fuel mixtures as well as CFD simulation,the results of the study show a strong indication of a positive synergy in mixing some of these biomasses as compared with a fuel mix-ture consisting only of coal and one type of biomass.Practically no power derating of the boiler occurs until the biomass content in the fuel mixture is~30%on a mass basis.The reduction in greenhouse gas emissions also appears significant from the results of the CFD simulation of this study,which is characterized by a decrease in the fraction of CO_(2) in flue gas from 21.5%for coal alone as fuel to 15.9%in the case of cofiring excluding the CO_(2) attributed to the biomass.展开更多
A promising scheme for coal-fired power plants in which biomass co-firing and carbon dioxide capture technologies are adopted and the low-temperature waste heat from the CO_(2) capture process is recycled to heat the ...A promising scheme for coal-fired power plants in which biomass co-firing and carbon dioxide capture technologies are adopted and the low-temperature waste heat from the CO_(2) capture process is recycled to heat the condensed water to achieve zero carbon emission is proposed in this paper.Based on a 660 MW supercritical coal-fired power plant,the thermal performance,emission performance,and economic performance of the proposed scheme are evaluated.In addition,a sensitivity analysis is conducted to show the effects of several key parameters on the performance of the proposed system.The results show that when the biomass mass mixing ratio is 15.40%and the CO_(2) capture rate is 90%,the CO_(2) emission of the coal-fired power plant can reach zero,indicating that the technical route proposed in this paper can indeed achieve zero carbon emission in coal-fired power plants.The net thermal efficiency decreases by 10.31%,due to the huge energy consumption of the CO_(2) capture unit.Besides,the cost of electricity(COE)and the cost of CO_(2) avoided(COA)of the proposed system are 80.37/MWhand41.63/tCO_(2),respectively.The sensitivity analysis demonstrates that with the energy consumption of the reboiler decreasing from 3.22 GJ/tCO_(2) to 2.40 GJ/tCO_(2),the efficiency penalty is reduced to 8.67%.This paper may provide reference for promoting the early realization of carbon neutrality in the power generation industry.展开更多
Using a 1-MWe slipstream pilot plant,solid-sorbent-based post-combustion CO_(2) capture was tested at a coal-fired power plant.Results from pilot testing were used to develop a preliminary full-scale commercial design...Using a 1-MWe slipstream pilot plant,solid-sorbent-based post-combustion CO_(2) capture was tested at a coal-fired power plant.Results from pilot testing were used to develop a preliminary full-scale commercial design.The sorbent selected for pilot-scale evaluation during this project consisted of an ion-exchange resin that incorporated amines covalently bonded to the substrate.A unique temperature-swing-absorption(TSA)process was developed that incorporated a three-stage fluidized-bed adsorber integrated with a single-stage fluidized-bed regenerator.Overall,following start-up and commissioning challenges that are often associated with first-of-a-kind pilots,the pilot plant operated as designed and expected,with a few key exceptions.The two primary exceptions were associated with:(i)handling characteristics of the sorbent,which were sufficiently different at operating temperature than at ambient temperature when design specifications were established with lab-scale testing;and(ii)CO_(2) adsorption in the transport line between the regenerator and adsorber that preloaded the sorbent with CO_(2) prior to entering the adsorber.Results from the pilot programme demonstrate that solid-sorbent-based post-combustion capture can be utilized to achieve 90%CO_(2) capture from coal-fired power plants.展开更多
文摘The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The environmental management of hazardous waste in coal-fired power plants started late, and there are many problems in the construction and management of their storage facilities. In this paper, taking eight typical coal-fired power plants as examples, the present problems of hazardous waste storage facilities in coal-fired power plants are analyzed, and corresponding countermeasures are put forward to solve the main common problems.
文摘In China, according to the relative up-to-date regulations and standards, the maincontrol measure for NOX emission of coal-fired power plants is, in principle, low NOXcombustion. However, in recent years, more and more newlyapproved coal-fired plantswere required to install flue gas denitrification equipment. This article expounds if fluegas denitrification is necessary from several aspects, including constitution of NOX, itsimpact to environment, operation ofdeNOXequipment in USA, as wellas the differencein ambient air quality standard between China and World Health Organization. It setsforth themes in urgent need of study and areas where deNOX equipment is necessaryfor new projects, besides a recommendation that the emission standards for thermalpowerplants should be revised as soon as possible in China.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (No.XDB40010200)the National Natural Science Foundation of China (Nos.41976220 and 41776190)the National Key Research and Development Program of China (No.2020YFA0608501)。
文摘Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power plants.However,the effects of coal-fired power plants on soil microbial communities have received little attention through atmospheric pollutant deposition and coal-stacking.Here,we collected the samples of power plant soils(PS),coal-stacking soils(CSS)and agricultural soils(AS)around three coal-fired power plants and background control soils(BG)in Huainan,a typical mineral resource-based city in East China,and investigated the microbial diversity and community structures through a high-throughput sequencing technique.Coal-stacking significantly increased(p<0.05)the contents of total carbon,total nitrogen,total sulfur and Mo in the soils,whereas the deposition of atmospheric pollutants enhanced the levels of V,Cu,Zn and Pb.Proteobacteria,Actinobacteria,Thaumarchaeota,Thermoplasmata,Ascomycota and Basidiomycota were the dominant taxa in all soils.The bacterial community showed significant differences(p<0.05)among PS,CSS,AS and BG,whereas archaeal and fungal communities showed significant differences(p<0.01)according to soil samples around three coal-fired power plants.The predominant environmental variables affecting soil bacterial,archaeal and fungal communities were Mo-TN-TS,Cu-V-Mo,and organic matter(OM)-Mo,respectively.Certain soil microbial genera were closely related to multiple key factors associated with stacking coal and heavy metal deposition from power plants.This study provided useful insight into better understanding of the relationships between soil microbial communities and long-term disturbances from coal-fired power plants.
文摘The United States is one of the world’s leaders in electricity production,generating about 4116 billion kWh in 2021,of which coal accounted for 21.8%of the total.This study applies an integrated approach using both terrestrial and satellite data to specifically examine emissions from coal-fired power plants and its spatial extent.The study also highlights the effectiveness of government policies to reduce emissions.It was found that emission of pollutants from the country’s energy sector has been steadily declining,with annual emissions of sulfur dioxide(SO_(2))and nitrogen oxides(NOx)decreasing from the US electric power sector between 1990 and 2020 by 93.4%and 84.8%,respectively,and carbon dioxide(CO_(2))by 37%between 2007 and 2020.Although overall emissions from coal-fired power plants are declining,some individual plants have yet to install environmental equipment to control emissions.According to US government data,major emitters of SO_(2),NO_(x),and CO_(2) in the US are the Martin Lake power plant in East Texas,the Labadie power plant near St.Louis,Missouri,and the James H Miller Jr plant near Birmingham,Alabama.This study also integrates TROPOMI satellite data to detect point emissions from individual power plants.While the highest levels of measured pollutants were over the country’s major cities and areas of fossil fuel extraction,TROPOMI could clearly distinguish the pollution caused by power plants in more rural areas.Although the US has made great strides in reducing emissions from coal-fired power plants,these plants still represent a major source of pollution and remain a major concern.Totally eliminating coal as a power source will be difficult with the higher power demands resulting from the transition to electric automobiles.
基金financial support of National Key Research&Development Project of China(2018YFB0605101)National Natural Science Foundation of China(No.201706050)+1 种基金Key Project Natural Science Foundation of Tianjin(18JCZDJC39800)The Science and Technology Key Project of Tianjin(18ZXSZSF00040,18KPXMSF00080,18PTZWHZ00010)。
文摘China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)including selenium(Se),mercury(Hg),lead(Pb),arsenic(As),etc.,from Coal-Fired Power Plants(CFPPs),which are the major toxic air pollutants causing widespread concern.For this reason,it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions.The study herein reviews various techniques applied in China for the selected HTEs emission control,including the technical,institutional,policy,and regulatory aspects.The specific areas covered in this study include health effects,future coal production and consumption,the current situation of HTEs in Chinese coal,the chemistry of selected HTEs,control techniques,policies,and action plans safeguarding the emission control.The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development.The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China.Future research should focus on the simultaneous removal of HTEs,PM,SOx,and NOx in the complex flue gas.
基金This project is supported by the Chinese National Key R&D Program(No.2018YFB0605205)the Zhejiang Provincial Natural Science Foundation(Grant No.LQ21E060001).
文摘To make coal-fired power generation more environmentally friendly,China has initiated a series of ultra-low emission ret-rofits to the air pollution control(APC)system of the existing power plants.In this study,a life cycle assessment(LCA)is conducted to analyze the environmental net benefits for the typical ultra-low emission retrofit of a 1000 MW power plant.The key processes,substances,and APC devices are verified and discussed.The results confirm that the retrofit effectively decreases the environmental stress of acidification potential(AP),eutrophication potential(EP),and photochemical ozone creation potential(POCP)by 69%-79%,which can be attributed to significantly reduced emissions at the stack.However,the retrofit has also increased other impact categories by 24%-79%,primarily due to the consumption of additional elec-tricity and adsorbents.The retrofit of selective catalytic reduction,electrostatic precipitator(ESP),and wet limestone flue gas desulfurization devices has a dominant effect on the impacts of EP,human toxicity potential(HTP),and AP.A newly installed wet ESP shows some environmental benefits(only for AP),but causes considerable burdens,in particular for the investigated impact categories global warming potential(GWP),marine aquatic ecotoxicity(MAETP),and abiotic depletion fossil(ADP fossil).The obtained results indicate that the hidden environmental consequences,which are associated with the production of energy and materials,need to be examined more comprehensively to inform the development of ultra-low emission technologies and strategies effectively.
文摘The flue gas pollutants deep-removal technology(DRT) focusing on PM2.5removal is the prime method of further reducing pollutants emission from coal-fired power plants. In view of the four key technological challenges in developing the DRT, studies were conducted on a series of purification technologies and the DRT was developed and successfully applied in 660 MW and 1000 MW coal-fired units. This paper analyzes the application results of the demonstration project, and proposes a roadmap for the follow-up researches and optimizations.
文摘Coal-fired power operators continue to look for ways to increase the efficiency and extend the working lives of their plants by improving operational flexibility and reducing environmental impact.Two possible options are explored here:combining solar energy with coal-fired power generation,and cofiring natural gas in coal-fired plants.Both techniques show potential.Depending on the individual circumstances,both can increase the flexibility of a power plant whilst reducing its emissions.In some cases,plant costs could also be reduced.Clearly,any solar-based system is limited geographically to locations that receive consistently high levels of solar radiation.Similarly,although many coal-fired plants already burn limited amounts of gas alongside their coal feed,for cofiring at a significant level,a reliable,affordable supply of natural gas is needed.This is not the case everywhere.But for each technology,there are niche and mainstream locations where the criteria can be met.The need for good solar radiation means that the uptake of coal-solar hybrids will be limited.Cofiring natural gas has wider potential:currently,the largest near-term market appears to be for application to existing coal-fired plants in the USA.However,where gas is available and affordable,potential markets also exist in some other countries.
基金funded by the National Natural Science Foundation of China(52006079)the Natural Science Foundation of Hubei Province(2020CFB247)the National Key Research and Development Program of China(2018YFB0605201)。
文摘On-site measurements of volatile organic compounds(VOCs)in different streams of flue gas were carried out on a real coal-fired power plant using sampling bags and SUMMA canisters to collect gas samples,filters to collect particle samples.Gas chromatography-flame ionization detector/mass spectrometry and gas chromatography-mass spectrometry was the offline analysis method.We found that the total mass concentration of the tested 102 VOC species at the outlet of wet flue gas desulfuration device was(13456±47)μg·m^(-3),which contained aliphatic hydrocarbons(57.9%),aromatic hydrocarbons(26.8%),halogen-containing species(14.5%),and a small amount of oxygen-containing and nitrogencontaining species.The most abundant species were 1-hexene,n-hexane and 2-methylpentane.The top ten species in terms of mass fraction(with a total mass fraction of 75.3%)were mainly hydrocarbons with a carbon number of 6 or higher and halogenated hydrocarbons with a lower carbon number.The mass concentration of VOC species in the particle phase was significantly lower than that in the gas phase.The change of VOC mass concentrations along the air pollution control devices indicates that conventional pollutant control equipment had a limited effect on VOC reduction.Ozone formation potential calculations showed that aromatic hydrocarbons contributed the highest ozone formation(46.4%)due to their relatively high mass concentrations and MIR(maximum increment reactivity)values.
基金The work was supported by the National Key Research and Development Plan of China(No.2016YFB0600605).
文摘In order to reduce the environmental smog caused by coal combustion,air pollution control devices have been widely used in coal-fired power plants,especially of wet flue gas desulfurization(WFGD)and wet electrostatic precipitator(WESP).In this work,particulate matter with aerodynamic diameter less than 10μm(PM_(10))and sulfur oxides(SO_(x))have been studied in a coal-fired power plant.The plant is equipped with selective catalytic reduction,electrostatic precipitator,WFGD,WESP.The results show that the PM_(10)removal efficiencies in WFGD and WESP are 54.34%and 50.39%,respectively,and the overall removal efficiency is 77.35%.WFGD and WESP have effects on the particle size distribution.After WFGD,the peak of particles shifts from 1.62 to 0.95μm,and the mass concentration of fine particles with aerodynamic diameter less than 0.61μm increases.After WESP,the peak of particle size shifts from 0.95 to 1.61μm.The differences are due to the agglomeration and growth of small particles.The SO_(3)mass concentration increases after SCR,but WFGD has a great influence on SO_(x)with the efficiency of 96.56%.WESP can remove SO_(x),but the efficiency is 20.91%.The final emission factors of SO_(2),SO_(3),PM_(1),PM_(2.5)and PM_(10)are 0.1597,0.0450,0.0154,0.0267 and 0.0215(kg·t^(−1)),respectively.Compared with the research results without ultra-low emission retrofit,the emission factors are reduced by 1~2 orders of magnitude,and the emission control level of air pollutants is greatly improved.
文摘Xiangfan Coal-fired Power Plant, a key energy construction project matched with Three Gorges Project, approved by the State Council. formally started to build in the suburb of Xiangfan City, Hubei Province on November 29, 1996.
文摘On October 21, 2003, the first unit of Taishan PowerPlant-the largest coal-fired power plant plannedcurrently in Asia, was successfully connected to the power grid to generate electricity.
基金The authors would like to thank the support from the Beijing Natural Science Foundation(JQ21010)National Science Fund for Distinguished Young Scholars(51925604)+1 种基金National Key R&D Plan of China(2018YFE0117300)International Partnership Program,Bureau of International Cooperation of Chinese Academy of Sciences(182211KYSB20170029).
文摘This paper proposed a novel integrated system with solar energy,thermal energy storage(TES),coal-fired power plant(CFPP),and compressed air energy storage(CAES)system to improve the operational flexibility of the CFPP.A portion of the solar energy is adopted for preheating the boiler’s feedwater,and another portion is stored in the TES for the CAES discharging process.Condensate water from the CFPP condenser is used for cooling compressed air during the CAES charging process.The thermodynamic performance of the integrated system under different load conditions is studied.The system operations in a typical day are simulated with EBSILON software.The system enables daily coal saving of 9.88 t and reduces CO_(2)emission by 27.95 t compared with the original CFPP at 100%load.Under partial load conditions,the system enables maximum coal saving of 10.29 t and maximum CO_(2)emission reduction of 29.11 t at 75%load.The system has maximum peak shaving depth of 9.42%under 40%load condition.The potential of the system participating ancillary service is also discussed.It is found that the integration of solar thermal system and CAES system can bring significant ancillary service revenue to a conventional CFPP.
文摘This paper takes the specific characteristics of pulverized coal room in thermal power plant as the starting point,firstly,this paper analyzes the process layout and structure selection,and then the structural design and vibration design requirements of coal crusher house are introduced in this paper.Finally,based on the engineering example,a new structure form of vibration isolation design is creatively proposed,which provides a new design idea for the practical engineering design.
基金supported by the Science and Technology Project of Guizhou Province(No.QKHJC[2020]1Y187)the National Natural Science Foundation of China(Nos.41265008,42007305,and 22166009)。
文摘Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned particulate matter(PM)around the ULE-retrofitted CF-PPs are less understood.Here,total Hg and its chemical speciation in TSP(total suspended particles),PM_(10)(aerodynamic particle diameter≤10μm)and PM_(2.5)(aerodynamic particle diameter≤2.5μm)around a ULE-retrofitted CFPP in Guizhou Province were quantified.Atmospheric PM_(2.5)concentration was higher around this ULE-retrofitted CFPP than that in the intra-regional urban cities,and it had higher mass Hg concentration than other sizefractioned PM.Total Hg concentrations in PM had multifarious sources including CFPP,vehicle exhaust and biomass combustion,while they were significantly higher in autumn and winter than those in other seasons(P<0.05).Regardless of particulate size,atmospheric PM-bound Hg had lower residual fractions(<21%)while higher HCl-soluble fractions(>40%).Mass concentrations of exchangeable,HCl-soluble,elemental,and residual Hg in PM_(2.5)were higher than those in other size-fractioned PM,and were markedly elevated in autumn and winter(P<0.05).In PM_(2.5),HCl-soluble Hg presented a significantly positive relationship with elemental Hg(P<0.05),while residual Hg showed the significantly positive relationships with HCl-soluble Hg and elemental Hg(P<0.01).Overall,these results suggested that atmospheric PM-bound Hg around the ULE-retrofitted CFPP tends to accumulate in finer PM,and has higher bioavailable fractions,while has potential transformation between chemical speciation.
文摘The cofiring of biomass and coal may be one of the most effective methods to improve energy utilization efficiency and reduce greenhouse gas emissions.This study aims to investigate combustion performance,interaction and synergistic effects in the cofiring of coal and three types of biomass.Blended fuel consisting of coal and three types of biomass such as sawdust,rice husk and solid recovery fuel was selected as the research object.Ultimate and proximate analysis and differential thermogravimetric analysis with heating rates of between 10°C and 40°C/minute are used to analyse combustion characteristics.Simulation of combustion in a 600-MWe steam power plant with a Carolina-type boiler is also carried out with the help of computational fluid dynamic(CFD)analysis to see the effect of the interaction and synergy of the mixed fuel on the performance of the steam generator.The effect on the com-bustion process in the combustion chamber of a steam power plant is also simulated.Based on the analysis of several test results of parameters such as ignition temperature,burnout temperature,calorific value of the fuel mixtures as well as CFD simulation,the results of the study show a strong indication of a positive synergy in mixing some of these biomasses as compared with a fuel mix-ture consisting only of coal and one type of biomass.Practically no power derating of the boiler occurs until the biomass content in the fuel mixture is~30%on a mass basis.The reduction in greenhouse gas emissions also appears significant from the results of the CFD simulation of this study,which is characterized by a decrease in the fraction of CO_(2) in flue gas from 21.5%for coal alone as fuel to 15.9%in the case of cofiring excluding the CO_(2) attributed to the biomass.
基金supported by the National Natural Science Foundation of China(Grant No.51806062)the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grant No.51821004)the Fundamental Research Funds for the Central Universities(Grant No.2020MS006).
文摘A promising scheme for coal-fired power plants in which biomass co-firing and carbon dioxide capture technologies are adopted and the low-temperature waste heat from the CO_(2) capture process is recycled to heat the condensed water to achieve zero carbon emission is proposed in this paper.Based on a 660 MW supercritical coal-fired power plant,the thermal performance,emission performance,and economic performance of the proposed scheme are evaluated.In addition,a sensitivity analysis is conducted to show the effects of several key parameters on the performance of the proposed system.The results show that when the biomass mass mixing ratio is 15.40%and the CO_(2) capture rate is 90%,the CO_(2) emission of the coal-fired power plant can reach zero,indicating that the technical route proposed in this paper can indeed achieve zero carbon emission in coal-fired power plants.The net thermal efficiency decreases by 10.31%,due to the huge energy consumption of the CO_(2) capture unit.Besides,the cost of electricity(COE)and the cost of CO_(2) avoided(COA)of the proposed system are 80.37/MWhand41.63/tCO_(2),respectively.The sensitivity analysis demonstrates that with the energy consumption of the reboiler decreasing from 3.22 GJ/tCO_(2) to 2.40 GJ/tCO_(2),the efficiency penalty is reduced to 8.67%.This paper may provide reference for promoting the early realization of carbon neutrality in the power generation industry.
基金supported by the US Department of Energy,National Energy Technology Laboratory(DE-FE0004343)with additional support from ADA-ES,Inc.,EPRI and Southern Company.
文摘Using a 1-MWe slipstream pilot plant,solid-sorbent-based post-combustion CO_(2) capture was tested at a coal-fired power plant.Results from pilot testing were used to develop a preliminary full-scale commercial design.The sorbent selected for pilot-scale evaluation during this project consisted of an ion-exchange resin that incorporated amines covalently bonded to the substrate.A unique temperature-swing-absorption(TSA)process was developed that incorporated a three-stage fluidized-bed adsorber integrated with a single-stage fluidized-bed regenerator.Overall,following start-up and commissioning challenges that are often associated with first-of-a-kind pilots,the pilot plant operated as designed and expected,with a few key exceptions.The two primary exceptions were associated with:(i)handling characteristics of the sorbent,which were sufficiently different at operating temperature than at ambient temperature when design specifications were established with lab-scale testing;and(ii)CO_(2) adsorption in the transport line between the regenerator and adsorber that preloaded the sorbent with CO_(2) prior to entering the adsorber.Results from the pilot programme demonstrate that solid-sorbent-based post-combustion capture can be utilized to achieve 90%CO_(2) capture from coal-fired power plants.
