Coal-fired Electric Power Plants Research Articles

Reduced wettability in compacted coal fly ash due to organosilane treatment

Organosilane (OS) treatment for water repellency has gained attention as a mechanism for mitigating leaching and for possible beneficial reuse of coal combustion residuals, particularly coal fly ash (CFA). However, little effort has been devoted to understanding the interaction between OS-treated CFA and water under conditions representative of field applications. In this study, the construction conditions of OS-treated CFA were simulated in the laboratory, and the degree of induced water repellency was investigated through contact angle measurements. A class F CFA from a coal-fired electric power plant ash impoundment and a commercially available OS were used. Besides CFA geotechnical and geochemical characterisation, samples were prepared by post-compaction treatment of CFA with OS solutions applied by spraying, which simulates a field irrigation truck. Results indicate that a 7% volume concentration of the OS solution is appropriate for construction purposes. However, the degree of water repellency, as measured by using contact angles, is strongly dependent on the water content of the compacted CFA. This suggests that the contractor should compact the CFA first, then apply truck-mounted jet drying or a similar technique and finally spray the OS solution on the surface. Results also demonstrate that about 84% of the treatment accumulates in the upper 5 cm of the compacted CFA.

Coal Criminals: Crimes of the Powerful, Extractivism and Historical Harm in the Global South

AbstractThis article provides a criminological analysis of the extraction, consumption, and disposal of coal in the Caribbean and the global south. It looks at how the transnational corporation Applied Energy System (AES) and its 454-megawatt coal-fired electric power plant in Puerto Rico has manufactured a transnational network of environmental harm and violence. The paper aims to demonstrate how coloniality, law, and state-corporate deviance enable the coal sector- a habitual environmental offender- to engage in systemic harm across different jurisdictions and states of the global south. To do so, we engage with the work of scholars in the green criminology (treadmill of production), state-corporate crimes (crimes of development), and crimes of the powerful (Ecocide and Carbon Criminal) traditions. Furthermore, this article briefly describes the stories of resistance taking place in Puerto Rico. In doing so, the article describes the criminogenic practices behind this fossil fuel industry, and how it has taken advantage of colonial practices, thus enhancing the historical harm manufactured by modernity and replicated within the neoliberal economy.

Spatial distribution, risk assessment, and source identification of the potentially toxic elements in the water-level fluctuation zone of the Dahuofang Reservoir, Northeast China.

Potentially toxic elements (PTEs), including cadmium (Cd), copper (Cu), lead (Pb), zinc (Zn), mercury (Hg), and chromium (Cr), in the water-level fluctuation zone (WLFZ) of the Dahuofang Reservoir were surveyed in regard to their concentrations, spatial distributions, risks, and possible sources. Sediment samples were collected at 12 typical sites located in the WLFZ of the Dahuofang Reservoir. The median values of Cd, Cu, Pb, Zn, and Cr all exceeded the soil background values in Liaoning Province. Based on the spatial distributions of these PTEs, the highest enrichment occurred at the R12 site. Cadmium, Cu, and Pb attained the highest contents at R12. The mean geoaccumulation index (Igeo) value of Cd indicated heavy contamination, and that of Pb indicated moderate to heavy contamination, while those of Cu and Zn indicated none to moderate contamination. The negative Igeo values of Cr and Hg indicated the uncontaminated level. According to the potential ecological risk index (RI), Pb posed a moderate risk, while Cd posed a high risk, Zn, Cr, Hg, and Cu posed a low risk. The R12 site exhibited the highest ecological risk. By applying multivariate statistical analysis, two principal components were extracted representing 62.992% of the total variance, and the results showed that the accumulation of Cr, Pb, and Hg might be ascribed to a nearby coal-fired electric power plant. Cadmium, Cu, and Zn were enriched owing to mineral sources, agricultural contamination, and coal combustion.

Effect of concrete unit weight on the mechanical properties of bottom ash aggregate concrete

The depletion of natural aggregates has already progressed significantly in some regions and countries, including South Korea, and it is critical to identify replacement materials to address this problem. In recent decades, researchers have focused on low-cost industrial residues or solid waste as potential solutions, and this study involves application of bottom ash (BA), a byproduct of coal-fired electrical power plants, as fine and coarse aggregates. The application of BA to the manufacture of concrete is noteworthy in terms of economic as well as ecological aspects for preserving natural resources. In the experiment, a total of 20 concrete containing bottom ash (CCBA) mixtures classified according to W/C and the bottom ash aggregate (BAA) mixing ratios were evaluated for their workability and various mechanical properties. The results of the experiment showed that the factor having the greatest effects on the mechanical properties of concrete was the usage of coarse BAA or lack thereof, and that the rates of decline in mechanical properties due to the replacement of fine BAA were within levels that could be controlled by other design factors, such as W/C. This study provides a comparison between the experimental results and the prediction results of several existing design codes, which will serve as basic data for proposing a reliable, predictive CCBA structural design model.

Research Activities of CO2 Capture and Utilization Technologies at the Wyoming Integrated Test Center

The State of Wyoming along with private partners has constructed a post combustion carbon dioxide (CO2) capture and utilization test center, the Wyoming Integrated Test Center (ITC) for the testing of post-combustion CO2 separation and utilization technologies at a coal-fired electric generation power plant located at Basin Electric Power Cooperative’s Dry Fork Station (DFS). The plant is located seven miles north of Gillette, Wyoming. Additional project partners include Tri-State G&T, National Rural Electric Cooperative Association, Black Hills Energy, and Rocky Mountain Power. The ITC provides space for researchers to test CO2 capture, utilization (CCU) technologies using a combined 26 MWe of actual coal based flue gas. The 26 MWe equivalent of flue gas is split among one large test center and six smaller test bays. During commissioning of the flue gas delivery system, 23.5 MWe was determined to be available for the large test center while 2.5 MWe was available for distribution to the 6 smaller test bays. The flue-gas slip-stream is taken downstream of the state-of-the-art emissions control systems which substantially reduce criteria pollutants such as SO2, NOX, and Hg. Flue gas is supplied to the test bays with the following composition for the coal derived flue gas: Component Minimum Maximum Average CO2 12% 13.1% 12.7% O2 1.7% 4.2% 2.5% N2 + Ar 66.7% 66.7% 66.7% H2O 15.2% 18.3% 18.1% SO2 0.0 ppm 114.9 ppm 23.1 ppm NOx 19.2 ppm 38.4 ppm 27.8 ppm Temperature (1) 80 C 90 C 85 C The ITC’s first tenant deployed in 2019, and is a hybrid CO2 capture system designed by TDA Research. Using a membrane supplied by Membrane Technology and Research, the TDA system uses a combination of membrane and proprietary sorbent developed by TDA Research to capture 90% of the CO2 from the flue gas with a lower energy penalty than conventional amine based systems. TDA’s system will be followed up by a novel system developed by Kawasaki Heavy Industries that uses a solid sorbent combined with temperature and pressure swing to regenerate the material using waste heat. This project is advancing into the detailed design phase to determine precise footprint and utility interconnect requirements at the Wyoming ITC. In addition, in Q1 of 2020, teams competing for the NRG COSIA Carbon XPRIZE will begin to deploy. The XPRIZE is a $20 million global competition to develop breakthrough technologies that will convert CO2 emissions from power plants and industrial facilities into valuable products like building materials, alternative fuels, and other commercial products. Carbon Upcycling UCLA is in the process of finalizing HAZOP analyses and permitting, and will move to site in February or March 2020 to deploy their system capable of using CO2 from flue gas to cure precast concrete pieces. They will soon be followed by Dimensional Energy which has obtained an operating permit to photo-catalytically convert CO2 to CO for making synthesis gas. Additional contestants include C4X which plans to make polymers and insulation materials, Breathe which will manufacture methanol, and Carbon Capture Machine which has a process to produce precipitated calcium carbonate. Additional research activity continues with the subdivision of the large test center into two bays to accommodate two additional large pilot CO2 capture systems of approximately 200 tons per day each. One system utilizes technology developed at the University of Kentucky Center for Applied Energy Research and will utilize amine based solvents with advanced heat integration. The other system will be a membrane system provided by Membrane Technology and Research. Both projects are currently funded through a phase 2 contract through the National Energy Technology Laboratory and US Department of Energy. Dry Fork Station and the ITC have completed a relative accuracy test audit to verify a sufficient supply of flue gas for both projects. Additionally, utility requirements have been determined to be within the scope and capability of the ITC to provide the necessary power, water, and space requirements to accommodate both systems. Finally, a memorandum of understanding between the Japanese Coal Association (JCOAL), Columbia University, and GreenOre LLC to pursue research in CO2 utilization at the Wyoming ITC. The goal would be to produce a range of products from coal derived fly ash as well as investigate the possibility of concentrating rare earth elements in the residual ash. This paper provides a comprehensive update of the research activities at the Wyoming ITC which has been selected to host nine different technology providers from five different countries at scales ranging from 10 MWe.

Simplified Mercury Extraction from Coal Fly Ash for Quantification of Total Mercury by ELISA-based Immunoassay.

A simplified two-step mercury extraction procedure enabled the selective and reproducible mercury recovery from actual coal fly ash (CFA). The optimized extraction procedure involving conventional enzyme-linked immunosorbent assay (ELISA)-based immunoassay allowed the ultra-sensitive quantification of total mercury content in CFA. The total mercury content of 41 CFA samples were successfully determined using the above-mentioned method, and the results were in agreement with those obtained by standard instrumental analysis (thermal decomposition atomic absorption spectrometry) within a 15% coefficient of variation. Our method for total mercury quantification is not only simple but suitable for management of the mercury content at coal-fired electric power plants and landfill sites, which deal with large amounts of waste CFA.

Effect of crushing conditions of crushing rate in process analysis of sewage-sludge organic solid-fuel crusher using the discrete element method

Owing to environmental problems generated in the course of economie growth, the industry is implementing renewable portfolio stan-dards (RPS) for companies that own power generation facilities with capacities equal to or in excess of 500 MW. In coal-fired electrical power plants, renewable portfolio standards are implemented using sewage sludge organic solid fuels to address environmental problems. Currently, sewage sludge organic solid fuels are crushed using a hammer mill operated in the co-firing mode. However, the hammer mill has low operation efficiency owing to the fast wear and tear and frequent breakdowns of the hammer and grate that constitute two of its key components. Therefore, the development of a crusher with increased durability and high-operation efficiency is necessary. In this study, a roller-type crusher was designed for the organic solid fuels of the sewage sludge that was operated with the use of compression and friction forces. The effect of the crushing condition of the designed roller type sewage-sludge organic solid-fuel crusher was analyzed. In addition, fuel crushing analysis was carried out using the discrete element method (DEM). Based on the DEM analysis results, the effect of process parameters (rotation speed of the rotor, roller size) of the roller type sewage-sludge solid-fuel crusher on the crushing rate was analyzed. A fuel crushing experiment was conducted using the roller-type crusher used for sewage-sludge organic solid fuels. In addition, the crushing rates against the amount of fuel discharge according to the DEM results and fuel crushing experiments were compared.

EPA drops, replaces rules for coal CO2 releases

Carbon dioxide emissions from US coal-fired electric power plants will be allowed to continue unabated for at least 4 more years under the Trump administration’s final Affordable Clean Energy (ACE) rule issued June 19 by the US Environmental Protection Agency. The rule gives states 3 years to develop and the EPA 1 year to approve approaches to comply with new power-plant efficiency requirements. Those requirements include reducing the amount of fuel used to generate a kilowatt-hour of electricity. The ACE rule replaces tougher regulations set by the Obama administration’s Clean Power Plan (CPP), which was intended to reduce coal-based emissions. The CPP regulations are currently on hold under a court-ordered stay. Speaking before an audience of coal-state Congress members, coal miners wearing hard hats, and coal and electricity industry representatives, EPA administrator Andrew Wheeler, himself a former coal lobbyist, stressed the importance of coal to the economy and the need

Coeffect of Air Pollution Control Devices on Trace Element Emissions in an Ultralow Emission Coal-Fired Power Plant

In this study, distribution, partitioning concentration, balance rate, and removal efficiency of trace elements (TEs) in an ultralow emission coal-fired electric power plant (EPP) were investigated and evaluated. Results include determination of the TEs in flue gas, coal, fly ash, bottom ash, gypsum, limestone, makeup water, wet flue gas desulfurization (WFGD) wastewater, and wet electrostatic precipitator (WESP) wastewater. The results indicate that most of the TEs are distributed in the fly ash, with a smaller portion in the bottom ash. The concentration of TEs in the flue gas gradually decreases as the gas moves through the air pollution control devices (APCDs). Only a small amount of TEs is emitted from the stack (Be: 0.039 μg/m3, Cd: 0.019 μg/m3, Cr: 2.229 μg/m3, Ni: 0.350 μg/m3, Pb: 0.194 μg/m3, Sb: 0.017 μg/m3, Se: 0.307 μg/m3, and U: 0.029 μg/m3). The Se concentration in the liquid portion was high and thus significantly contributed to the material balance. The low-temperature economizer-electrost...

Improvement in benthic habitat environment via granulated coal ash in a water body exposed to wastewater discharge

The discharge of untreated wastewater into a water body strongly deteriorates the benthic habitat environment of bottom sediment. In this study, field experiments were conducted in the Fukuyama inner harbor (Hiroshima, Japan), which is exposed to large amounts of untreated domestic wastewater discharge. The water quality in this harbor is seriously deteriorated during the summer season, resulting in an aggravation of the marine biological environment. This study examines the improvement in benthic habitat environment at the bottom of the harbor via the use of granulated coal ash (GCA, a by-product of coal-fired electric power plants). In the field experiments, the pore water quality and benthic habitat quality (i.e., the abundance and species richness) in GCA, gravel, and sediment layers were observed over time. The experiment results suggest that both GCA and gravel provide a better habitat environment for benthos compared to the sediment. In addition, the species richness in GCA was higher than that in gravel, suggesting that benthos can more easily survive in GCA than in gravels. It appears that the absorptive ability of GCA can remove the reductants released from the anaerobic digestion of organic matter and that the dissolution of the chemical components of GCA is significant factors in creating the higher species richness in the GCA layer.

Experimental Study of Thermophysical Properties of Peat Fuel

A study has been made of thermophysical properties of peat pellets of higher-than-average reactivity due to the pretreatment of the raw material. A synchronous differential analysis of the produced pellets was performed to determine the gaseous products of their decomposition by the mass-spectroscopy method. The parameters of the mass loss rate, the heat-release function, the activation energy, the rate constant of the combustion reaction, and the volatile yield were compared to the properties of pellets compressed by the traditional method on a matrix pelletizer. It has been determined that as a result of the peat pretreatment, the yield of volatile components increases and the activation energy of the combustion reaction decreases by 17 and 30% respectively compared with the raw fuel. This determines its prospects for burning in an atomized state at coal-fired thermal electric power plants.

Pollution Abatement and Employment.

Morgenstern et al. (2002) is well-known for its investigation of the employment effects of environmental regulations. However, the cost function specified in that paper is handicapped by its reliance on survey data of the costs of inputs assigned to pollution abatement. In this paper, we specify an input distance function that models the joint production of good and bad outputs. This allows us to measure the relative importance of factors associated with changes in employment without pollution abatement cost data. We operationalize our model using a sample of 80 coal-fired electric power plants from 1995-2005.

Leaching Kinetics of As, Mo, and Se from Acidic Coal Fly Ash Samples

Annually, coal-fired electric power plants produce large volumes of potentially hazardous coal combustion products (CCPs) including fly ash. Since majority of the coal fly ash and other CCPs deposited in dry land fills or wet lagoons, they pose risk of contamination to local environment. In this study, we present results of leaching kinetics for As, Mo, and Se from three acidic fly ash samples collected from coal-fired power plants in the southeastern United States. This study shows that the leachate concentrations of As, Mo, and Se increase over time. Three kinetics equations, pseudo-second order, Elovich, and power-function, are able to adequately describe the experimental leaching kinetics data. Experimental leaching data and modeling results indicate that the rate limiting leaching of As, Mo, and Se is controlled by the diffusional process responsible for transferring these elements from interior to the surface of the particles as well as the dissolution of the fly ash particles. Therefore, it is important to adopt effective containment/treatment schemes to avoid potential and persistent dispersion of trace elements from ash disposal facilities to surrounding environment for a long time.

Adoption of SO2 emission control technologies - An application of survival analysis

Using data on coal-fired electric power plants, this article investigates the contributing factors affecting the investment decisions on flue-gas desulfurization (FGD), a capital-intensive emission control technology. The paper makes two contributions to the literature. First, the public regulatory status of electric power plants is found to have a strong influence on whether FGD investment is made. Compared to deregulated power plants, those that are still under rate-of-return regulations by Public Utility Commissions are more likely to install FGD. Second, a higher rate of inspections of polluting facilities (not just electric utility power plants) in a state in the previous year is associated with a higher probability of power plants adopting FGD this year. In addition, sulfur content of coal and plant size are both positively associated with the likelihood of FGD installation. The service length of boilers is negatively associated with the likelihood.

캐나다 아퀴스토어 탄성파자료를 통한 이산화탄소 지중저장 연구지역 대수층 특성화

캐나다 아퀴스토어 프로젝트는 인근의 화력발전소에서 포집한 이산화탄소를 심부 약 3,500 m에 존재하는 염대수층에 저장하는 포집, 수송, 주입 및 저장의 전 과정을 포함하는 세계 최초의 통합 실증 프로젝트이다. 이산화탄소의 저장소로서의 염대수층은 기존의 한정적으로 분포된 석유가스 저류층과 비교했을 때 전 세계 어디서나 분포하므로 이에 대한 실증 연구는 이산화탄소 지중저장의 저변 확대에 큰 의미가 있다. 염대수층에 이산화탄소를 주입하고 추적하기 위해서는 지하의 물성을 파악하고 특성화해야 한다. 본 연구는 캐나다 아퀴스토어 이산화탄소 지중저장 현장의 탄성파 탐사자료로부터 석유가스 자원 탐사에 이용되는 진폭 변화 분석기술을 응용하여 지중저장 대상지층의 유체 포화 특성을 도출하였다. 시추공 검층자료에서 해석된 이산화탄소 저장층 구간의 상부 및 하부는 Winnipeg층 1,815 ms과 Deadwood 층 1,857 ms로 탄성파 자료와 대비하였다. 대상 구간의 탄성파 기록으로부터 입사각에 따른 진폭 크기변화를 확인한 결과 자료의 상관성은 45 %에서 81 % 범위였다. 종축절편과 진폭구배 속성을 교차출력한 결과는 반비례 관계를 보여 전형적인 함수 퇴적층에 해당하였다. 계산된 속성들에서 대수층의 기저를 공간적으로 도시하였고 이산화탄소 지중저장 구간의 포아송비 변화를 예측하였다. The Aquistore project is the world's first commercial capture, transportation, utilization and storage project of post-combustion <TEX>$CO_2$</TEX> from a coal-fired thermo electric power plant, and the proposed storage is a saline aquifer at a depth of about 3,500 m. Deep saline aquifer, compared to hydrocarbon reservoir, provides the great volumetric potential for storage of <TEX>$CO_2$</TEX> anywhere in the world, therefore the research results from the project may be exported globally to other sites. Geological <TEX>$CO_2$</TEX> storage characterization for saline aquifer instead of hydrocarbon reservoir needs to estimate the geophysical properties of subsurface geology. This study calculated the geophysical property of water-saturated formation by applying amplitude variation analysis developed from oil and gas exploration. We correlated horizon tops at the well logs to seismic traveltime of 1,815 and 1,857 ms as Winnipeg and Deadwood formations. Gradient analysis from seismic traces showed correlation coefficient of 45 - 81 % on amplitude variation with respect to incident angle. Crossplot of intercept and gradient shows the inverse proportional trend which represents typical water saturated sediments. Product attribute of intercept and gradient described the base of wet sediment. Poisson's ratio change attribute increased at the top of target area satisfying with wet sediment and decreased at the top of basement in a dry rock bed.

Mercury deposition and methylmercury formation in Narraguinnep Reservoir, southwestern Colorado, USA

Narraguinnep Reservoir in southwestern Colorado is one of several water bodies in Colorado with a mercury (Hg) advisory as Hg in fish tissue exceed the 0.3μg/g guideline to protect human health recommended by the State of Colorado. Concentrations of Hg and methyl-Hg were measured in reservoir bottom sediment and pore water extracted from this sediment. Rates of Hg methylation and methyl-Hg demethylation were also measured in reservoir bottom sediment. The objective of this study was to evaluate potential sources of Hg in the region and evaluate the potential of reservoir sediment to generate methyl-Hg, a human neurotoxin and the dominant form of Hg in fish. Concentrations of Hg (ranged from 1.1 to 5.8ng/L, n=15) and methyl-Hg (ranged from 0.05 to 0.14ng/L, n=15) in pore water generally were highest at the sediment/water interface, and overall, Hg correlated with methyl-Hg in pore water (R2=0.60, p=0007, n=15). Net Hg methylation flux in the top 3cm of reservoir bottom sediment varied from 0.08 to 0.56ng/m2/day (mean=0.28ng/m2/day, n=5), which corresponded to an overall methyl-Hg production for the entire reservoir of 0.53g/year. No significant point sources of Hg contamination are known to this reservoir or its supply waters, although several coal-fired power plants in the region emit Hg-bearing particulates. Narraguinnep Reservoir is located about 80km downwind from two of the largest power plants, which together emit about 950kg-Hg/year. Magnetic minerals separated from reservoir sediment contained spherical magnetite-bearing particles characteristic of coal-fired electric power plant fly ash. The presence of fly-ash magnetite in post-1970 sediment from Narraguinnep Reservoir indicates that the likely source of Hg to the catchment basin for this reservoir has been from airborne emissions from power plants, most of which began operation in the late-1960s and early 1970s in this region.

Potential gains from trading bad outputs: The case of U.S. electric power plants

Jointly with kilowatt-hours (kWh), electric power plants also produce CO2, NOx, and SO2. In this paper, we apply an environmental production model based on data envelopment analysis (DEA) to compare the production of kWh under command-and-control regulation of the undesirable byproduct with tradable permit regulation of the byproduct. This is done for each of the three undesirable outputs and combinations of them. We apply our model to a dataset of 80 coal-fired electric power plants from 1995 to 2005. From this we can identify the potential gains from trading the most common undesirable outputs produced by coal-fired electric power plants.

Tradable permits and unrealized gains from trade

With the advent of tradable permit programs for bad outputs (e.g., SO2 emissions); concerns arose over whether the theoretical gains from trade would be realized. We will employ a methodology that calculates the potential gains accruing to coal-fired electric power plants from implementing a tradable permit program. The magnitude of the potential gains in a plant's kilowatt hour output from a tradable permit program relative to its observed production provides insights into the existence of intertemporal allocative inefficiencies and spatial allocative inefficiencies after the implementation of a tradable permit program.

Dissolution of Rare Earth Elements from Coal Fly Ash Particles in a Dilute H&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;SO&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; Solvent

Recently, the worldwide supply of rare earth element (REE) resources will be severely restricted. On the other hand, coal fly ash particles emitted from coal-fired electric power plants contain relatively high concentrations of REEs. The contents of REEs in coal fly ash are regularly several hundreds of ppmw. In order to extract and recover REEs from coal fly ash particles, as a first step, we have investigated their dissolution behavior in a dilute H2SO4 solvent. The REE content of coal fly ash specimens has been precisely determined, and their presence in the ash component of the original coal and their enrichment in coal fly ash particles during coal combustion have been suggested. REEs in coal fly ash dissolve gradually in H2SO4 over time, and this implies two types of occurrences of the REEs in coal fly ash particles. By applying the unreacted core model to the dissolution behavior of REEs in a H2SO4 solvent, we can explain both types of occurrences.

Federal Regulation of Coal-Fired Electric Power Plants to Reduce Greenhouse Gas Emissions

This article focuses on legal developments since mid-2011 relating to the control of both carbon dioxide (CO2) and conventional pollutants from coal-fired electric power plants. It deals as briefly as possible with pre-2011 issues that are discussed in the author’s numerous publications over the past decade dealing with climate change.