Large Coal-fired Power Plants Research Articles

Industrial Verification and Research Development of Lime–Gypsum Fertilizer Granulation Method

This work concerns non-pressure granulation of mineral materials used for the production of agricultural fertilizers for soil deacidification. In order to expand the product range of Nordkalk Poland sp. z o. o. located in Poland, the granulation conditions of the gypsum–lime mix were examined with the use of various granulation methods. The processed mixture was Jurassic lime flour mined in the Sławno mine (Poland) and waste gypsum (sulfogypsum) obtained from the largest coal-fired power plant in the EU, Bełchatów Power Plant (Poland). This paper presents the results of the optimization of the gypsum–lime fertilizer granulation process. The results of the study of granulation of gypsum–lime mixture realized in one-stage technology in a disc granulator were compared with the effects of two-stage agglomeration. During the research, a mixture (in a 1:1 ratio) of waste sulfogypsum and lime flour was used. Such a weight ratio provides maximum use of the sulfogypsum waste while maintaining good mechanical properties of the granulate. The granulated bed was moistened with a lignosulfonate solution. The process was carried out periodically. After the experiment, the grain composition of the granulate obtained was determined and tests were performed to determine the strength of the product. The test results were compared with analogous ones obtained during granulation with the use of molasses (waste from sugar production). The results obtained were verified during a trial carried out on an industrial scale.

The Application of base isolation in a power plant structure

In this paper, large general finite element software ABAQUS is used to contrast the isolation before and after the seismic performance of a large coal-fired power plants, the application of isolation technology in the main factory building structure has carried on the preliminary discussion. Through to the main factory building structure system of isolation design and comparison analysis, get the following conclusion: after using isolation technology, obviously improve the seismic performance of the structure, under the effect of earthquake resistance, the structure of the floor shear, layer displacement and acceleration were significantly decreased, and the upper structure under earthquake is basic to keep translation, isolation effect is obvious.

Installment of desulfurization equipment at coal-fired power plants in North Carolina and associations with preterm birth among surrounding residents

Background: Coal-fired power plants (CFPPs) are major contributors of air pollution globally. In 2002, North Carolina (NC) adopted regulation that required CFPPs to substantially reduce their sulfur dioxide (SO2) emissions by 2013. CFPPs complying with this regulation have resulted in measurable decreases of ambient SO2 across NC. Air pollution research suggests an association between ambient SO2 and preterm birth (PTB, gestational age < 37 completed weeks). PTB is an important risk factor for neonatal mortality and associated with high healthcare costs. This study aims to evaluate the impact of SO2 emissions reduction strategies at CFPPs on preterm birth in North Carolina.Methods: The US Environmental Protection Agency’s Air Markets Program data were used to determine when the SO2 emissions reduction strategies were implemented at NC’s largest CFPPs (capacity > 150 megawatts). The study population was derived from geocoded NC resident singleton live birth data from 2003-2015 obtained from the NC State Center for Health Statistics. A difference-in-difference analysis using a linear mixed model with random intercepts for the CFPPs will be employed to compare the risk of PTB for mothers living 0-5 miles and 5-10 miles from the CFPPs before and after the intervention, with a control of mothers living 10-15 miles from the CFPPs.Results: During the study period, 7 CFPPs installed desulfurization equipment (i.e. SO2 scrubbers). The median concentration for reported monthly SO2 air emissions from the CFPPs in the pre-period and post-period were 4,421 tons and 281 tons, respectively. With the spatial and temporal exposure restrictions applied, there were 42,076 births within 15 miles of the CFPPs.Conclusions: This study comes at a time when the United States government is considering whether to move away from or reinvest in coal for electricity generation.

Nanomineralogy of evaporative precipitation of efflorescent compounds from coal mine drainage

Efflorescent nanophases (NPs) are found as a transitory accumulation of potentially hazardous elements (PHEs), particularly in tropical climates. The central objective of this study was to investigate the distribution of PHEs with NPs through the evaporative formation structures (EFS) of enormously PHEs-rich coal-mine drainages (CMD). The EFS were studied in natural coal mine drainage for five months in order to determine their geochemical and ecological structures and to assess their position in the reduction of PHEs in nature. The largest coal-fired power plant in South America, located in south Brazil, is used as an example of such a problem. In this work, a novel methodology for the analysis of PHEs in CMD precipitates is proposed for this affected coal area. The analytical method, combining X-Ray Diffraction (XRD) and advanced electron microscopies, shows the importance of nanomineralogy in understanding different circumstances of coal contamination. Several ultrafine-nanoparticles (UNPs) were identified in the sampled soils and river sediments together with the PHEs. A decrease in PHEs was identified in association with UNPs. However, further investigations are required with regard to the mobility of PHEs in water, atmosphere, soils, and sediments. The EPS was thoroughly studied, acquiring suitable understanding with investigational facts for Ca and Fe-sulphates, pickeringite, and several amorphous phases.

Valorization Method for Hard Coal as Fuel for Nonindustrial Combustion Installations with Special Regard to Reduction of Mercury Content

Mercury and its compounds are classified as very toxic and they pose a real threat to human health. Coal combustion processes constitute one of the main sources of mercury emission to the environment. The use of hard coal by the sector of non-industrial combustion installations (among others households) is a special issue. In contrast to large coal-fired power plants, such users are not equipped with systems for reducing emissions. For this group of users, it is necessary to use hard coal with the lowest possible mercury content. In the paper, a method for the production of hard coal with low mercury content based on combined processes of the dry deshaling and thermal pretreatment was proposed. The proposed method allowed for a reduction of mercury content in the analyzed coals in the range from 43 to even 92% (in relation to its lower heating value). The produced coals were characterized by relatively low mercury contents from 1.5 to 4.8 µg/MJ with the average of 2.4 µg/MJ. The application of this method...

PM10 and PM2.5 Qualitative Source Apportionment Using Selective Wind Direction Sampling in a Port-Industrial Area in Civitavecchia, Italy

The possibility to discriminate between different emission sources and between natural and anthropogenic contributions is a key issue for planning efficient air pollution reduction and mitigation strategies. Moreover, the knowledge of the particulate matter (PM) chemical composition for the different size fractions is recognized as increasingly important, in particular with respect to health effects of exposed population. This study is focused on the characterization of PM10 and PM2.5 main sources located in the Civitavecchia harbor-industrial area (Central Italy), namely a large coal-fired power plant, a natural gas power plant, the harbor area, the vehicular traffic (due to both the local traffic and the highway crossing the area) and small industrial activities. The approach was based on PM10/PM2.5 samples monthly collected for one year and a further relative chemical characterization of organic and inorganic fractions. Wind-select sensors, allowing a selective PM10 and PM2.5 sampling downwind to specific emission sources, were used for the overall sampling. This methodology manages to explain specific emission patterns and to assess the concentration levels of the micro pollutants emitted by local sources and particularly toxic for health. A descriptive statistical analysis of data was performed, also verifying the occurrence of legislative threshold exceedances. Moreover, in order to highlight the contribution of specific sources, the differences in the measured micro pollutants concentrations between wind directions, PM size fractions and sampling sites have been investigated, as well as the seasonal trends of pollutants concentrations. These results allow to highlight that the applied methodology represents a valid support in source apportionment studies.

Renewable energy as a factor of sustainable development and regulation of ecological problems in Africa

The analysis of the main directions of renewable energy in Africa, as a factor in sustainable development and reduction of greenhouse gas emissions is performed. The ecological problems of the modern and prospective development of the energy complex of African countries are considered. For African countries the issue of ensuring reliable and environmentally friendly access to electricity for the population is extremely acute. It is shown, that the electricity demand for industry in Sub-Saharan Africa the most problematic region is growing on a very large scale. The construction of new large coal-fired thermal power plants in the required volumes will lead to serious environmental and climatic consequences. The study of regional data allowed us to conclude that PV solar systems are of priority importance for increasing people’s access to electricity in rural SubSaharan Africa. Based on numerous materials from international energy structures the estimates and calculations of volumes of reduction of greenhouse gas emissions due to the use of renewable energy sources as an alternative to carbon fuel are carried out. The study has shown that of particularly great importance for reducing CO2 emissions in Kenya is the development of geothermal energy.

МЕЗОМАСШТАБНЫЕ ПРОЦЕССЫ ПЕРЕНОСА АТМОСФЕРНЫХ ЗАГРЯЗНЕНИЙ В РАЙОНЕ ЮЖНОГО БАЙКАЛА

The article considers the results of experimental studies of mesoscale processes of atmospheric pollution transfer to the southern Baikal in the system of low-level atmospheric jet flows in the atmospheric boundary layer at heights up to 100–600 m. It is shown that the plumes of atmospheric emissions of large coal-fired power plants can be captured by the atmospheric jets and transferred to hundreds of kilometers without significant scattering and deposition. Such cases are observed, as a rule, at night and more often in the cold season of the year. The main pollutants in these plumes are sulfur dioxide and nitrous oxides, concentration of which in the region of Lake Baikal (70 km from the source) can reach the level from hundreds to thousands µg/m3. In the process of transfer, nitrogen oxides are partially oxidized by atmospheric ozone to nitrates (mainly to nitric acid), while ozone concentrations in the plume zone drop to zero, completely expending on oxidation.

Atmospheric protection technologies for coal thermal power plants in eastern regions of Russia

Environmental problems of thermal power plants in the eastern regions of Russia are associated with emission of a significant amount of pollutants into the atmosphere. In recent years, documents have been adopted in Russia at the government level concerning the introduction of modern innovative technologies in all industries, including the energy sector. On July 1, 2018, a reference book of the best available technologies became operative. This reference book contains a list and analysis of the best available technologies for large coal-fired heat power plants, including atmospheric protection measures. For large thermal power plants, three pollutants are primarily considered: particulate matter, nitrogen oxides and sulfur dioxide. For each of them, the article discusses the best available technologies for reducing emissions into the atmosphere. The atmospheric protection technologies include technologies of the preliminary preparation of fossil fuel for combustion as well as technical purification systems of each pollutant. Sulphur dioxide is the main impurity of emission from coal-fired thermal power plants, and one of the attractive ways to reduce its emissions is the thermal preparation of coal before combustion. This technology has been experimentally tested at ESI SB RAS. This article discusses preliminary estimates and calculated emissions obtained.

Distribution of potentially harmful elements in soils around a large coal-fired power plant.

An understanding of the spatial distribution and contribution of a power plant to local soil contamination is important for the planning of soil use and prioritizing remedial actions for public safety. Consequently, the aim of this study was to map the spatial distribution of potentially hazardous elements (PHEs; Cu, Pb, Zn, Ni, Cr, Fe, Mn, Cd, As, and Se) in soils around a large (796MW) coal-fired power plant in Brazil. For the purpose, 33 soil samples were collected in the area within a radius of approximately 17.5km from the plant and subsequently analyzed for PHEs. The frequency and direction of winds were also obtained from a meteorological station in the region. The sampling area was divided into four quadrants (northwest: N-NW; northeast: N-NE; southeast: S-SE; southwest: S-SW), and there were significant negative correlations between the distance and the concentrations of Se in the S-SE quadrant and As in the S-SW and S-SE quadrants. There were positive correlations between distance from the plant and the concentration of Mn in the N-NE quadrant and the concentration of Cd in the S-SW quadrant. The dominant direction of the winds was N-NE. The indexes used in this study showed low-to-moderate enrichment factor, but detailed analysis of the dominant quadrant of the winds showed a correlation with higher concentrations in the soils closer to the power plant for at least seven of the PHEs analyzed, especially with regard to As. Therefore, we conclude that the distribution of the metalloid As can be used as a marker of the spatial distribution of contamination from the thermoelectric plant, but the dynamics of the other elements suggests that the presence of other sources of contamination may also compromise the quality of local soils.

Air quality and health benefits from potential coal power plant closures in Texas

ABSTRACTAs power production from renewable energy and natural gas grows, closures of some coal-fired power plants in Texas become increasingly likely. In this study, the potential effects of such closures on air quality and human health were analyzed by linking a regional photochemical model with a health impacts assessment tool. The impacts varied significantly across 13 of the state’s largest coal-fired power plants, sometimes by more than an order of magnitude, even after normalizing by generation. While some power plants had negligible impacts on concentrations at important monitors, average impacts up to 0.5 parts per billion (ppb) and 0.2 µg/m3 and maximum impacts up to 3.3 ppb and 0.9 µg/m3 were seen for ozone and fine particulate matter (PM2.5), respectively. Individual power plants impacted average visibility by up to 0.25 deciviews in Class I Areas. Health impacts arose mostly from PM2.5 and were an order of magnitude higher for plants that lack scrubbers for SO2. Rankings of health impacts were largely consistent across the base model results and two reduced form models. Carbon dioxide emissions were relatively uniform, ranging from 1.00 to 1.26 short tons/MWh, and can be monetized based on a social cost of carbon. Despite all of these unpaid externalities, estimated direct costs of each power plant exceeded wholesale power prices in 2016.Implications: While their CO2 emission rates are fairly similar, sharply different NOx and SO2 emission rates and spatial factors cause coal-fired power plants to vary by an order of magnitude in their impacts on ozone, particulate matter, and associated health and visibility outcomes. On a monetized basis, the air pollution health impacts often exceed the value of the electricity generated and are of similar magnitude to climate impacts. This suggests that both air pollution and climate should be considered if externalities are used to inform decision making about power-plant dispatch and retirement.

A Pilot Survey of Potentially Hazardous Trace Elements in the Aquatic Environment Near a Coastal Coal-Fired Power Plant in Taiwan.

Background:A limited number of potentially hazardous trace elements were quantified in the aquatic environment near the world’s second largest coal-fired power plant (CFPP) and the coal combustion residual (CCR) disposition sites in Central Taiwan. We postulated that contamination from specific trace elements would be present in the abovementioned aquatic environments.Methods:Cross-sectional sampling of trace elements was first performed between September 24, 2017 and October 3, 2017 outside the CFPP, in the effluent sampled from Changhua, a county south of metropolitan Taichung, and at the historical CCR disposal sites, using the intertidal zone surface seawater and the seawater in an oyster farm as controls. Aqueous samples were collected from 12 locations for analysis of 13 trace elements (Al, As, B, Cd, total Cr, Co, Fe, Pb, Mn, Se, Sr, Tl, and V). We used inductively coupled plasma (ICP) optical emission spectrometry to determine B and Fe levels, and ICP mass spectrometry for all other trace elements. The Spearman rank correlation coefficient (Rho) was calculated to examine the pairwise relation among the trace elements.Results:Al (50% of all samples), B (66.7%), Fe (25%), Mn (50%), Sr (8.3%), and V (25%) were identified as being above the Environmental Protection Agency (EPA) regulation limit. The oyster farm seawater had no concerns. Mn (96.4 μg/L) in the CFPP drainage effluent was 1.9-fold above the regulation limit. Fe, Mn, and V were detected from the cooling channel at 4379, 625, and 11.3 μg/L, respectively. The effluent and water from the areas surrounding the 2 CCR dump sites revealed similar magnitudes of trace element contamination. B is highly correlated with Sr (Rho = 0.94, 95% confidence interval [CI], 0.80-0.98). Meanwhile, Fe is highly correlated with Al (Rho = 0.77), Pb (Rho = 0.71), Co (Rho = 0.75), and V (Rho = 0.84).Conclusions:The EPA must set an explicit regulation limit for aluminum, boron, iron, and strontium in the aquatic environment. This exploratory research will inform policymaking regarding certain trace elements that could potentially have an adverse impact on public health and wildlife.

Discussion on the cause of scaling in wet desulfurization system of large coal-fired power plants

The flue gas desulfurization method of large coal-fired power plants is generally limestone/gypsum wet method. But many equipments of this wet desulfurization system during daily operation often cause scaling problems. At present, more literature think s this scale is caused by the mixing of desulfurized gypsum and fly ash in flue gas. However, this paper analyzes the scale composition and appearance of several power plants in China, which shows that the scale is not a simple mixture of gypsum and fly ash, and is a smelting reaction of fly ash in a complex environment and forms a hard scale of gypsum/limestone-fly ash gel. This kind of scale will endanger the safe and stable operation of the desulfurization system, specific operational and maintenance recommendations are proposed for reference.

Fog Water Chemical Composition on Ailaoshan Mountain, Yunnan Province, SW China

ABSTRACT Between December 2015 and March 2016, fog water was collected at the subtropical mountain cloud forest site Ailaoshan in SW China at 2476 m above mean sea level. An active fog collector was employed to collect 117 samples during more than 140 hours of fog, covering 6 major fog events. The chemical analysis included acidity and inorganic ion concentrations. The median pH values of the fog events varied between 3.7 and 4.2, characterizing the fog water as acidic (pH < 5.0) to very acidic (pH < 4.0). The ion composition was dominated by H+, NH4+, SO42– and NO3–, which made up more than 86% of the total ionic concentration (TIC). The generally rather high ion concentration levels cannot be explained by nearby emission sources but rather by long-range transport of air pollutants from various sources in East Asia. During one event on February 8, 2016, it is evident that it was the emissions from a large coal-fired power plant in Myanmar that led to high concentrations of sulphuric acid. This pilot study of fog chemistry in rural, mountainous SW China should be complemented by studies spanning the moist summer monsoon season and covering more chemical species.

The impact of time-varying CO2 injection rate on large scale storage in the UK Bunter Sandstone

Carbon capture and storage (CCS) is expected to play a key role in meeting targets set by the Paris Agreement and for meeting legally binding greenhouse gas emissions targets set within the UK (Energy and Climate Change Committee, 2016). Energy systems models have been essential in identifying the importance of CCS but they neglect to impose constraints on the availability and use of geologic CO2 storage reservoirs. In this work we analyse reservoir performance sensitivities to varying CO2 storage demand for three sets of injection scenarios designed to encompass the UK's future low carbon energy market. We use the ECLIPSE reservoir simulator and a model of part of the Southern North Sea Bunter Sandstone saline aquifer. From a first set of injection scenarios we find that varying amplitude and frequency of injection on a multi-year basis has little effect on reservoir pressure response and plume migration. Injectivity varies with site location due to variations in depth and regional permeability. In a second set of injection scenarios, we show that with envisioned UK storage demand levels for a large coal fired power plant, it makes no difference to reservoir response whether all injection sites are deployed upfront or gradually as demand increases. Meanwhile, there may be an advantage to deploying infrastructure in deep sites first in order to meet higher demand later. However, deep-site deployment will incur higher upfront cost than shallow-site deployment. In a third set of injection scenarios, we show that starting injection at a high rate with ramping down, a low rate with ramping up or at a constant rate makes little difference to the overall injectivity of the reservoir. Therefore, such variability is not essential to represent CO2 storage in energy systems models resolving plume and pressure evolution over decadal timescales.

Assessment of dose rate to terrestrial biota in the area around coal fired power plant applying ERICA tool and RESRAD BIOTA code

This paper presents the environmental radiation risk assessment based on two software program approaches ERICA Tool (version 1.2) and RESRAD BIOTA (version 1.5) to estimate dose rates to terrestrial biota in the area around the largest coal fired power plant in Serbia. For dose rate assessment software's default reference animals and plants and the best estimated values of activity concentrations of 238U, 234U, 234Th, 232Th, 230Th, 226Ra, 210Pb, 210Po, 137Cs in soil were used. Both approaches revealed the highest contribution to the internal dose rate due to 226Ra and 210Po, while 137Cs contributed the most to the external dose rate. In the investigated area total dose rate to biota derived using ERICA Tool ranged from 0.3 to 14.4 μGy h−1. The natural radionuclides exhibited significantly higher contribution to the total dose rate than the artificial one. In the investigated area, only dose rate for lichens and bryophytes exceeded ERICA Tool screening value of total dose rate of 10 μGy h−1 suggested as confident that environmental risks are negligible. The assessed total dose rates for reference animals and plants using RESRAD BIOTA were found to be 7 and 3 μGy h−1, respectively. In RESRAD BIOTA - Level 3, 10 species (Lumbricus terrestris, Rana lessonae, Sciurus vulgaris, Anas platyrhynchos, Lepus europaeus, Vulpes vulpes, Capreolus capreolus, Suss crofa, Quercu srobur, Tilia spp.) representative for the study area were modeled. Among them the highest total dose rate (4.5 μGy h−1) was obtained for large mammals. Differences in the predicted dose rates to biota using the two software programs are the consequence of the difference in the values of transfer parameters used to calculate activity concentrations in biota. Doses of ionizing radiation estimated in this study will not exhibit deterministic effects at the population level. Thus, the obtained results indicate no significant radiation impact of coal fired power plant operation on terrestrial biota. This paper confirms the use ERICA Tool and RESRAD BIOTA softwares as flexible and effective means of radiation impact assessment.

Local steam temperature imbalances of coal-fired boilers at very low load

In order to remain economically viable, even large coal-fired power plants must be operated more often in partial load. Due to an unfavourable coal mills configuration, the local temperatures in the combustion chamber can differ. This can affect the temperatures in two parallel steam lines so much that even a shut-down of the entire system would be necessary. The modelling and subsequent simulation of the plant is a proven way to identify problems and to show the limits of the minimum load.

Linking the Effect of Reservoir Injectivity and CO2 Transport Logistics in the Nordic Region

We compare the cost for CO2-transport by ship with cost for pipeline transport in the Nordic region as a function of transport volume and distance. We also calculate the pipeline volumetric break-even point yielding the minimum CO2 volume required from a specific site for pipeline to become the less costly transport option and finally, we investigate the effect injectivity may have on the choice of reservoir and transport mode. Most stationary CO2-emissions in the Nordic region originate from emission intensive industries such as steel, cement and chemical plants and refineries. Typically, their emissions are modest (less than 1 Mt per year) compared to large coal fired power plants, while distances to potential storage sites are considerable, often 300km or more. Hence, build-up of clusters of emission sources and CO2-volumes is likely to take time and be costly. At the same time, many of the emission sources, both fossil based and biogenic, are located along the coast line. The results imply that due to modest CO2-volumes and relatively long transport distances CO2 transport by ship is the least costly transportation option for most of the sources individually as well as for most of the potential cluster combinations during ramp-up of the CCS transport and storage infrastructure. It is furthermore shown that cost of ship transport increases modestly with increasing transport distance which, in combination with poor injectivity in reservoirs in the Baltic Sea, indicate that it may be less costly to transport the CO2 captured from Finnish and Swedish sources located along the Baltic Sea a further 800-1300km to the west by ship for storage in aquifers with higher injectivity in the Skagerrak region or in the North Sea.

Long-range transport of plumes of atmospheric emissions from regional coal power plants to the South Baikal water basin

We compare cases of actually observed regional transport of atmospheric pollutants to Lake Baikal against calculations according to a mathematical model. The observational data suggest that the most severe atmospheric pollution over the Lake is associated with atmospheric transport of sulfur and nitrogen dioxides from large coal-fired power plants both from the direction of Irkutsk and Angarsk, and from the direction of Buryatia (Ulan-Ude and Gusinoozersk). Transport of sulfur and nitrogen oxides to the Baikal atmosphere is especially strong at nighttime, under inversion-type meteorological conditions, in the form of weakly dispersed plumes from tall stacks of power plants. Data of automatic measurements of sulfur and nitrogen oxides demonstrate that actual mechanisms of anthropogenic pollutant transport to Lake Baikal are more complex and multiform as compared to model results. Model estimates of SO2 concentrations over the Lake are close to monthly average measurements; however, they fail to explain certain specific cases of increased pollutant concentrations in the Baikal atmosphere.

Greening the future: a case for environmental impact bonds

A central puzzle for environmental economics is how to integrate long-run costs and benefits into present-day decision making. Commonly this puzzle is described in terms of externalities. These occur when ‘an activity or transaction by some party causes an unintended loss or gain in welfare to another party, and no compensation for the change in welfare occurs’ (Daly and Farley, 2011, p.184). For example, the millions of tonnes of carbon dioxide that a large coal-fired power plant releases annually contributes to the cumulative problem of climate change, yet those who profit from producing electricity do not bear the burden of the negative consequences. Rather, these costs fall disproportionately upon future generations and communities uniquely vulnerable to the impacts of climate change. Thus, the emission of greenhouse gases creates a negative externality, because its costly impacts are external to the accounting of the actors who emit them.