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The effects of coal blending on the formation and properties of particulate matter during combustion
Ke Zhou,MingHou Xu,DunXi Yu,Chang Wen,ZhongHua Zhan,Hong Yao
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-010-3250-z
Abstract: The control of particulate matter (PM) emissions from coal combustion becomes an urgent work due to their adverse effects on human health. Coal blending is a promising option for submicron particulate (PM1) reduction. This study addressed the effects of coal blending on the formation and properties of particulate matter in combustion process. Coal blends from lignite and bituminous coal, with different blend ratios (9:1, 7:3, 5:5, 3:7 and 1:9), were combusted in a drop tube furnace. The mass size distribution, concentration, elemental composition and morphology of the particulate matter generated under O2/N2 and O2/CO2 conditions were characterized. Particulate matter was collected by a low pressure impactor (LPI), which aerodynamically segregated particulates into thirteen fractions with sizes ranging from 0.03 to 9.8 μm. The results showed that coal blending reduced PM1 generation, compared with the calculated average values from the combustion of constituent coals. This indicated that the mineral interactions had a great effect on PM1 reduction. The blend ratio also played an important role in the suppression of PM1 generation. In this experimental study, PM1 generation suffered a maximum suppression at the blend ratio of 7:3. The O2/CO2 atmosphere affected the formation and properties of the PM1 during coal blends combustion. Compared with the O2/N2 combustion, the interaction of minerals was weakened under O2/CO2 combustion, thus the suppression of PM1 generation decreased after coal blending. Compared with the calculated values, the concentrations and percentages of Ca, Fe in PM1 decreased, but the concentrations of Ca, Fe, Si and Al in coarse particulates (PM10+) increased after coal blends combustion. The interactions between the aluminosilicates in the bituminous coal and volatile elements Ca, Fe in the lignite were thought to contribute to the suppression of PM1 generation during the combustion of coal blends.
Coal Fineness Effect on Primary Particulate Matter Features During Pulverized Coal Combustion
煤粉细度对一次颗粒物特性的影响研究

L,
吕建燚
,李定凯

环境科学 , 2007,
Abstract: Three kinds of coal differed from fineness were burned in a laboratory-scale drop tube furnace for combustion test, and an 8-stage Andersen particle impactor was employed for sampling the primary particulate matter(PM), in order to study coal fineness effect on primary PM features during pulverized coal combustion. It has been shown that the finer the coal was, the finer the PM produced. PMi emission amount augmented with coal fineness decreased, and the amount of PM10 increased from 13 mg/g to 21 mg/g respectively generated by coarse coal and fine coal. The amount of PM2.5 increased from 2 mg/g to 8 mg/g at the same condition. Constituents and content in bulk ash varied little after three different fineness coal combustion, while the appearance of grading PM differed visibly. The value of REE increased while the coal fineness deceased. The volatility of trace elements which were investigated was Pb>Cr>Zn>Cu>Ni in turn. The concentration of poisonous trace elements was higher which generated from fine coal combustion. The volatilization capacity was influenced little by coal fineness,but the volatilization extent was influenced differently by coal fineness. Fine coal combustion affects worse environment than coarse coal does.
Caracterización de Partículas Suspendidas (PST) y Partículas Respirables (PM 10) producidas en áreas de Explotación Carbonífera a Cielo Abierto Characterization of Total Suspended Particles (TSP) and Inhalable Particulate Matter (PM 10) generated in Open Pit Coal Mining Areas  [cached]
Luis C Angulo,José I Huertas,Gloria M Restrepo
Información Tecnológica , 2011,
Abstract: Se presenta una revisión de la literatura sobre la cuantificación y caracterización de partículas suspendidas (PST) y partículas respirables (PM10) producidas en áreas de explotación carbonífera a cielo abierto. El material particulado es un contaminante complejo por sus características físicas (distribución de tama o de partícula, morfología y densidad) y por sus características químicas (compuestos orgánicos e inorgánicos, metales y contaminantes primarios y secundarios). Estas características son críticas para determinar el tipo y magnitud de los efectos sobre la salud humana. Se encontró que los trabajos realizados, han empleado experimentos de laboratorio y de campo, así como estudios de modelación. Esta revisión bibliográfica contribuye a una mejor comprensión y evaluación de las tecnologías que se deben usar para encontrar soluciones a este problema de contaminación. This article presents a literature review about the quantification and characterization of total suspended particles (TSP) and inhalable particulate matter (PM 10) generated in open pit coal mining areas. Particle matter is a complex pollutant due to its physical characteristics (particle size distribution, morphology and density) and its chemical characteristics (organic and inorganic components, metals, and primary and secondary pollutants). These characteristics are critical to determine the type and the magnitude of their effects on human health. It was found that the different works published in the literature have used lab and field experiments, and also modeling studies. This literature review contributes to improve the understanding and evaluation of technologies that must be used to find solutions to this atmospheric pollution problem.
Study of the Changes on Tree Shrew Bronchial Epithelium ?Induced by Xuanwei Bituminous Coal Dust  [PDF]
Xiaobo CHEN, Meng HE, Guangjian LI, Yongchun ZHOU, Guangqiang ZHAO, Yujie LEI, Kaiyun YANG, Linwei TIAN, Yunchao HUANG
- , 2015, DOI: : 10.3779/j.issn.1009-3419.2015.08.01
Abstract: Background and objective Lung cancer is the type of cancer with the highest incidence and mortality in numerous countries and regions. Establishing an appropriate animal model that can be used to simulate lung cancer etiology, pathogenesis, and similar processes, is urgent. We explore the feasibility of establishing a lung cancer model induced by Xuanwei bituminous coal dust PM10 (particulate matter with diameters of 10 μm or less), which affects bronchial epithelium of tree shrews. Methods The neck skin of adult tree shrews is dissected, and the thyroid cartilage is fully exposed. Subsequently, the weak part at the top of the thyroid cartilage is treated with intratracheal agents by perfusion via a special infusion needle puncture method. Regular X-ray examination and lung tissue biopsy were performed on the sacrificed animals to observe changes in pulmonary imaging and bronchial epithelial cells after perfusion of Xuanwei bituminous coal dust PM 10. Results The tree shrews of the experimental group (exposed to bituminous coal dust) died in a week after perfusion with PM10, whereas no animal died until the end of the experiment in the blank control and the solvent control groups. Sections of lung tissue biopsy of the regularly killed tree shrews were stained with hematoxylin and eosin. The lung tissues of tree shrews in the experimental group showed a serial changes caused by bronchial epithelial hyperplasia, such as squamous metaplasia, dysplasia, and early invasive carcinoma, whereas no significant pathological changes were observed in the blank control and solvent control groups. Conclusion Endotracheal infusion of Xuanwei bituminous coal dust PM10 induces lung cancer in tree shrews. Thus, the lung cancer model was established.
CHEMICAL CHARACTERIZATION OF THE INHALABLE PARTICULATE MATTER IN CITY OF CHILLAN, CHILE
Celis,José; Morales,Roberto; Zaror,Claudio; Inzunza,Juan; Flocchini,Roberto; Carvacho,Omar;
Journal of the Chilean Chemical Society , 2003, DOI: 10.4067/S0717-97072003000200009
Abstract: inhalable particulate matter (pm10) measurements were performed in six different sites in the city of chillán, chile, during september 2001 to september 2002. chemical composition of pm10 was performed to samples of 47 mm diameter teflon membranes within the city of chillán. the spatial and temporal variability of the chemical composition of pm10 was evaluated taking into account additional data from meteorology and further air pollutants. the chemical analyses of pm10 showed that carbonaceous substances and crustal material were the most abundant components of pm10 during the winter and summer, respectively. the concentrations of pm10 were higher during the cold season than during the warm season. this was explained mainly due to the massive use of wood as fuel for residential heating within the city of chillán, producing a dense smoke cloud in those days of atmospheric stability. the pm10 concentrations were higher in the downtown area of the city of chillán, where also the chemical composition was more variable due to urban traffic and other anthropogenic sources
CHEMICAL CHARACTERIZATION OF THE INHALABLE PARTICULATE MATTER IN CITY OF CHILLAN, CHILE  [cached]
José Celis,Roberto Morales,Claudio Zaror,Juan Inzunza
Journal of the Chilean Chemical Society , 2003,
Abstract: Inhalable particulate matter (PM10) measurements were performed in six different sites in the city of Chillán, Chile, during September 2001 to September 2002. Chemical composition of PM10 was performed to samples of 47 mm diameter Teflon membranes within the city of Chillán. The spatial and temporal variability of the chemical composition of PM10 was evaluated taking into account additional data from meteorology and further air pollutants. The chemical analyses of PM10 showed that carbonaceous substances and crustal material were the most abundant components of PM10 during the winter and summer, respectively. The concentrations of PM10 were higher during the cold season than during the warm season. This was explained mainly due to the massive use of wood as fuel for residential heating within the city of Chillán, producing a dense smoke cloud in those days of atmospheric stability. The PM10 concentrations were higher in the downtown area of the city of Chillán, where also the chemical composition was more variable due to urban traffic and other anthropogenic sources
Primary investigation of the pollution status of polycyclic aromatic hydrocarbons (PAHs) in water and soil of Xuanwei and Fuyuan, Yunnan Province, China
JunGang Lü,RenJi Xu,QingHua Zhang,JiYan Liu,ChunYang Liao,FuSheng Wei
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0499-2
Abstract: Lung cancer incidence in Xuanwei and Fuyuan is extremely high. The air pollution, especially indoor airborne PAHs generated by burning smoky coals, has been considered as the most probable reason. The air pollution may affect drinking water and soil through dry and wet deposition. In this study, the concentrations of PAHs in water and soil samples from Xuanwei and Fuyuan were monitored to investigate the influence of atmospheric PAHs pollution on water and soil. No obvious PAHs pollution in water was found in these two areas, indicating that airborne PAHs have no apparent effect on the drinking water (well water). The smoky coal combustion from household and industry, such as the activities related to power plants, coking plants and chemical industries, is responsible for the soil PAHs pollution in these two areas. The soil pollution might be the reemission source and would pose long-term threat to the local environment and health of residents.
Molecular Epidemiology Study in Xuanwei: the Relationship among?Coal Type, Genotype and Lung Cancer Risk  [PDF]
Jihua LI, Jun HE, Rui TANG, Wei HU, Qing LAN, Xingzhou HE, Yun LI, Yunsheng ZHANG
- , 2015, DOI: : 10.3779/j.issn.1009-3419.2015.01.03
Abstract: Background and objective It has been proven that the lung cancer mortality rate in Xuanwei County, China was among the highest in the country and has been associated with exposure to indoor smoky coal emissions that contain high levels of polycyclic aromatic hydrocarbons. This risk may be modified by variation in genetic polymorphisms and coal subtypes. Our objective was to use molecular epidemiological techniques to investigate the relationship among genetic polymorphisms, coal subtype and lung cancer risk in Xuanwei County. Methods On the basis of two population-based case-control studies in residents of Xuanwei County, China, questionnaires covering demographic information, smoking history, family and personal medical history, and information on other variables were administered and buccal cells and sputum samples were collected separately from each subject enrolled to extract DNA. GST superfamily, AKR1C3 superfamily, OGG1 superfamily and other genotype were scanned by useing PCR method. ORs and 95%CIs were used to estimate the association between genotypes, coal subtypes and lung cancer risk factors by conditional Logistic regression using Statistical Analysis Software. Results Compared with subjects who using smokeless coal or wood, smoky coal use was statistically significantly associated with lung cancer risk (OR=7.7, 95%CI: 4.5-13.3). There was marked heterogeneity in risk estimates for specific subtypes of smoky coal. Estimates were highest for coal from the Laibin (OR=24.8), Longtan (OR=11.6) and Baoshan (OR=6.0) coal types, and lower for coal from other types; the risk within the same subtype of coal in male and female were similar. The GSTM1-null genotype, the AKR1C3 (Ex1-70C>G), OGG1 (Ex6-315C>G) genotypes were closely associated with increased risk of lung cancer in Xuanwei County, and their odds ratios (95%CI) were 2.3 (1.3-4.2), 1.8 (1.0-3.5) and 1.9 (1.1-3.3), respectively. Compared to subjects who with GSTM1-positive and used less than 130 tons of smoky coal during their lifetime, higher risks were closely associated with GSTM1-null and heavier users (≥130 tons), with the OR was 4.9 (95%CI: 1.3-18.2) and 2.7 (95%CI: 1.0-7.4) for female and male, respectively. However, higher risks were only found within female for AKR1C3 (Ex1-70C>G) and OGG1 (Ex6-315C>G), with OR (95%CI)=12.9 (2.2-107.8) and 5.7 (1.1-34.2), respectively. Conclusion Lung cancer risks varied among coal subtypes; however, risks were similar between men and women exposed to the same type of coal. The GSTM1-null genotype may enhance susceptibility to air
Navajo Coal Combustion and Respiratory Health Near Shiprock, New Mexico  [PDF]
Joseph E. Bunnell,Linda V. Garcia,Jill M. Furst,Harry Lerch,Ricardo A. Olea,Stephen E. Suitt,Allan Kolker
Journal of Environmental and Public Health , 2010, DOI: 10.1155/2010/260525
Abstract: Indoor air pollution has been identified as a major risk factor for acute and chronic respiratory diseases throughout the world. In the sovereign Navajo Nation, an American Indian reservation located in the Four Corners area of the USA, people burn coal in their homes for heat. To explore whether/how indoor coal combustion might contribute to poor respiratory health of residents, this study examined respiratory health data, identified household risk factors such as fuel and stove type and use, analyzed samples of locally used coal, and measured and characterized fine particulate airborne matter inside selected homes. In twenty-five percent of homes surveyed coal was burned in stoves not designed for that fuel, and indoor air quality was frequently found to be of a level to raise concerns. The average winter 24-hour PM2.5 concentration in 20 homes was 36.0 g/m3. This is the first time that PM2.5 has been quantified and characterized inside Navajo reservation residents' homes.
Effective identification of the three particle modes generated during pulverized coal combustion
DunXi Yu,MingHou Xu,Hong Yao,XiaoWei Liu,Ke Zhou
Chinese Science Bulletin , 2008, DOI: 10.1007/s11434-008-0192-x
Abstract: Based on the mass fraction size distribution of aluminum (Al), an improved method for effectively identifying the modes of particulate matter from pulverized coal combustion is proposed in this study. It is found that the particle size distributions of coal-derived particulate matter actually have three modes, rather than just mere two. The ultrafine mode is mainly generated through the vaporization and condensation processes. The coarse mode is primarily formed by the coalescence of molten minerals, while the newly-found central mode is attributed to the heterogeneous condensation or adsorption of vaporized species on fine residual ash particles. The detailed investigation of the mass fraction size distribution of sulfur (S) further demonstrates the rationality and effectiveness of the mass fraction size distribution of the Al in identifying three particle modes. The results show that not only can the number of particle modes be identified in the mass fraction size distributions of the Al but also can their size boundaries be more accurately defined. This method provides new insights in elucidating particle formation mechanisms and their physico-chemical characteristics.
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