Considerations on FGD in Coal-Fired Power Plants

Aiming at issues on flue gas des-ulfurization facing coal-fired power plants inChina, such as process selection, whetheradopting flue gas desulfurization (FGD) or not,qualification of flue gas desulfurization en-gineering company, the localization of technicalequipment, charge for SO2 emission andnormalized management, this article makes acomprehensive analysis and puts forwardconstructive suggestions. These will providesome references for those being engaged in fluegas desulfurization in coal-fired power plants.[

Environmental life cycle assessment of Indian coal-fired power plants

Coal is the backbone of the Indian power sector. The coal-fired power plants remain the largest emitters of carbon dioxide, sulfur dioxide and substantial amounts of nitrogen oxides, which are associated with climate and health impacts. Various CO2 mitigation technologies （carbon capture and storage--CCS） and SO2/NOx mitigation technologies （flue gas desulfurization and selective catalytic reduction） have been employed to reduce the environmental impacts of the coal-fired power plants. Therefore, it is imperative to understand the feasibility of various mitigation technologies employed. This paper attempts to perform environmental life cycle assessment （LCA） of Indian coal-fired power plant with and without CO2, SO2 and NOx mitigation controls. The study develops new normalization factors for India in various damage categories, using the Indian emissions and energy consumption data, coupled with the emissions and particulate emission to come up with a final environmental impact of coal-fired electricity. The results show a large degree of dependence on the perspective of assessment used. The impact of sensitivities of individual substances and the effect of plant efficiency on the final LCA results is also studied.

Progress and prospects of innovative coal-fired power plants within the energy internet

The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy internet. Progressive penetration of intermittent renewable energy sources into the energy system has led to unprecedented challenges to the currently wide use of coal-fired power generation technologies. Here, the applications and prospects of advanced coal-fired power generation technologies are analyzed. These technologies can be summarized into three categories:(1) large-scale and higher parameters coal-fired power generation technologies, including 620/650/700 oC ultra-supercritical thermal power and double reheat ultra-supercritical coal-fired power generation technologies;(2) system innovation and specific, highefficiency thermal cycles, which consist of renewable energy-aided coal-fired power generation technologies, a supercritical CO_2 Brayton cycle for coal-fired power plants, large-scale air-cooling coal-fired power plant technologies, and innovative layouts for waste heat utilization and enhanced energy cascade utilization;(3) coal-fired power generation combined with poly-generation technologies, which are represented by integrated gasification combined cycle(IGCC) and integrated gasification fuel cell(IGFC) technologies. Concerning the existing coal-fired power units, which are responsible for peak shaving, possible strategies for enhancing flexibility and operational stability are discussed. Furthermore, future trends for coal-fired power plants coupled with cyber-physical system(CPS) technologies are introduced. The development of advanced, coal-fired power generation technologies demonstrates the progress of science and is suitable for the sustainable development of human society.

Formation and emission characteristics of VOCs from a coal-fired power plant

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.

Optimization of an Existing Coal-fired Power Plant with CO²Capture

Nowadays, the worsening environmental issue caused by CO2 emission is greatly aggravated by human activity. Many CO2 reduction technologies are under fast development. Among these, monoethanolamine (MEA) based CO2 capture technology has been paid great attention. However, when connecting the CO2 capture process with a coal-fired power plant, the huge energy and efficiency penalty caused by CO2 capture has become a serious problem for its application. Thus, it is of great significance to reduce the related energy consumption. Based on an existing coal-fired power plant, this paper proposes a new way for the decarburized retrofitting of the coal-fired power plant, which helps to improve the overall efficiency of the power plant with less energy and efficiency penalty. The decarburized retrofitting scheme proposed will provide a new route for the CO2 capture process in China.

Field Studies on the Removal Characteristics of Particulate Matter and SO_(x) in Ultra-Low Emission Coal-Fired Power Plant

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.

Problems of Hazardous Waste Storage Facilities in Coal-fired Power Plants and Countermeasures

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.

Development of Carbon Dioxide Capture Technologies in Coal-Fired Power Plants

With a particular reference to China Huaneng Group's practices in CO_2 capture, this article presents a brief ing on the current development of CO_2 capture technologies in coal-fired power plants both in China and abroad. Sooner or later, the integration of CO_2 capture and storage (CCS) facility with coal-fired power plant will be inevitably put on the agenda of developers.

Xiangfan Coal-fired Power Plant - a matched large power plant for Three Gorges Project starts to construct

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.

Carbon Dioxide Mineralisation and Integration with Flue Gas Desulphurisation Applied to a Modern Coal-Fired Power Plant

For Finland, carbon dioxide mineralisation was identified as the only option for CCS （carbon capture and storage） application. Unfortunately it has not been embraced by the power sector. One interesting source-sink combination, however, is formed by magnesium silicate resources at Vammala, located -85 km east of the 565 MWe coal-fired Meri-Pori Power Plant on the country＇s southwest coast. This paper assesses mineral sequestration of Meri-Pori power plant CO2, using Vammala mineral resources and the mineralisation process under development at Abo Akademi University. That process implies Mg（OH）E production from magnesium silicate-based rock, followed by gas/solid carbonation of the Mg（OH）2 in a pressurised fluidised bed. Reported are results on experimental work, i.e., Mg（OH）2 production, with rock from locations close to Meri-Pori. Results suggest a total CO2 fixation capacity -50 Mt CO2 for the Vammala site, although production of Mg（OH）2 from rock from the site is challenging. Finally, as mineralisation could be directly applied to flue gases without CO2 pre-capture, we report from experimental work on carbonation of Mg（OH）2 with CO2 and CO2-SO2-O2 gas mixtures. Results show that SO2 readily reacts with Mg（OH）2, providing an opportunity to simultaneously capture SO2 and CO2, which could make separate flue gas desulphurisation redundant.

Regulations and Practice on Flue Gas Denitrification for Coal-Fired Power Plants in China

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.

Effects of coal-fired power plants on soil microbial diversity and community structures

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.

Overlooked CO_(2)emissions induced by air pollution control devices in coal-fired power plants

China's efforts to mitigate air pollution from its large-scale coal-fired power plants(CFPPs)have involved the widespread use of air pollution control devices(APCDs).However,the operation of these devices relies on substantial electricity generated by CFPPs,resulting in indirect CO_(2) emissions.The extent of CO_(2)emissions caused by APCDs in China remains uncertain.Here,using a plant-level dataset,we quantified the CO_(2)emissions associated with electricity consumption by APCDs in China's CFPPs.Our findings reveal a significant rise in CO_(2)emissions attributed to APCDs,increasing from 1.48 Mt in 2000 to 51.7 Mt in 2020.Moreover,the contribution of APCDs to total CO_(2)emissions from coal-fired power generation escalated from 0.12%to 1.19%.Among the APCDs,desulfurization devices accounted for approximately 80%of the CO_(2)emissions,followed by dust removal and denitration devices.Scenario analysis indicates that the lifespan of CFPPs will profoundly impact future emissions,with Nei Mongol,Shanxi,and Shandong provinces projected to exhibit the highest emissions.Our study emphasizes the urgent need for a comprehensive assessment of environmental policies and provides valuable insights for the integrated management of air pollutants and carbon emissions in CFPPs.

Valuing Health Effects of Natural Radionuclides Releases from Yatagan Power Plant

The objective of this paper is the valuation of radiological health effects of Yatagan Power Plant. To this aim the radiation dose calculations are carried out for the population living within 80 km radius of the plant. The average of the maximum measured specific isotopes 238U, 232Th and 226Ra in the flying ash samples are considered as radioactive sources. Based on the dose calculations, first the stochastic health effects and then monetary health effects are estimated. The estimated total collective dose and economic value of the pre-dicted health effects are 0.3098 man Sv/y and 14791 US$/y respectively. The results obtained from the dose calculations are lower than the limits of International Commission of Radiation Protection (ICRP) and it does not pose any risk for public health. Monetary value of health risks is also negligible in comparison to the av-erage yearly sales revenue of the plant which is 250 million US$.

Optimization and Innovation of Engineering Design for Ninghai Power Plant

In order to build a power plant with high efficiency,low investment and zero warm water discharge,a series of innovations are applied to the two 1 000-MW units of Ninghai Power Plant.The new technologies include the closed-circuit system for seawater cooling tower with a spraying area of 13 000 m2,the main buildings with reinforced concrete structure,the plasma ignition system for tower boiler and the fieldbus control system.Optimization measures are taken in some aspects,such as the open point of the turbine overload valves,the boiler dimensions,the technical process,the electric system,the building structures and the layout of the power plant.The units have been running for more than half a year with the thermal efficiency as high as 45.79% and without warm water discharged,which indicates that all the systems are safe and steady and the original purpose of optimization has been realized.

Research on Structural Design of Coal Crusher House in Thermal Power Plant

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.

Emission control strategies of hazardous trace elements from coal-fired power plants in China

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.

Economic analysis of atmospheric mercury emission control for coal-fired power plants in China

Coal combustion and mercury pollution are closely linked, and this relationship is particularly relevant in China, the world＇s largest coal consumer. This paper begins with a summary of recent China-specific studies on mercury removal by air pollution control technologies and then provides an economic analysis of mercury abatement from these emission control technologies at coal-fired power plants in China. This includes a cost-effectiveness analysis at the enterprise and sector level in China using 2010 as a baseline and projecting out to 2020 and2030. Of the control technologies evaluated, the most cost-effective is a fabric filter installed upstream of the wet flue gas desulfurization system（FF ＋ WFGD）. Halogen injection（HI） is also a cost-effective mercury-specific control strategy, although it has not yet reached commercial maturity. The sector-level analysis shows that 193 tons of mercury was removed in 2010 in China＇s coal-fired power sector, with annualized mercury emission control costs of 2.7 billion Chinese Yuan. Under a projected 2030 Emission Control（EC） scenario with stringent mercury limits compared to Business As Usual（BAU） scenario, the increase of selective catalytic reduction systems（SCR） and the use of HI could contribute to 39 tons of mercury removal at a cost of 3.8 billion CNY. The economic analysis presented in this paper offers insights on air pollution control technologies and practices for enhancing atmospheric mercury control that can aid decision-making in policy design and private-sector investments.