Time series analysis of CO concentrations from an Eastern Kentucky coal fire

Coal fires in natural outcrops, in abandoned and active coal mines, and in coal and coal-refuse piles are responsible for the uncontrolled emissions of gases, including CO, CO₂, H₂S, hydrocarbons, and volatile aromatics. Typically, measurements of gases at a mine vent are made over a short time interval, perhaps no more than 10 min, including the time for replicate measurements. Such timing provides little information on longer-term variations in emissions, although comparisons of seasonal measurements suggest such changes do occur. To address this problem, we placed temperature and CO data loggers in coal fire vents to collect time series measurements for a period of up to three weeks. For one experiment, 11 days of data at one-minute intervals indicated that the CO emissions were generally in the 400–550 ppmv range. However near daily depressions in CO concentrations occurred and in some cases fell below 50 ppmv; followed by an increase to ~ 700–800 ppmv; in turn followed by a return to the ambient conditions. Data for a separate 21-day collection period in a different vent of the same fire exhibited similar trends, albeit at a higher CO concentration. The drop in CO concentration may be associated with a meteorologically-driven inhalation cycle of the fire, whereby air diluted the combustion generated CO. We propose this was followed by an increase in the intensity of the fire due to increased O₂ from the inhaled air, producing increased CO concentrations, before settling back to the ambient conditions.     

Impact of mercury emissions from incineration of automobile shredder residue in Japan

Mercury emissions from the incineration of automobile shredder residues (ASRs) were investigated. Continuous monitoring of elemental and reactive gaseous Hg in flue gas was performed in lab-scale and plant-scale ASR incineration. Results of continuous monitoring agreed with those obtained using the JIS K0222 method and Ontario-Hydro method. Before cleaning by air pollutant control devices (APCDs), reactive Hg was the dominant form of that element in both lab-scale and plant-scale results. Emission factors of reactive Hg before APCDs estimated from monitoring results showed large differences between plant-scale and lab-scale emissions. The emission factor in the plant scale was more than 10 times larger than that in the lab-scale, which is explainable by the different Hg contents of ASR. Based on plant-scale monitoring at the stack, emission factors after APCDs were estimated as 0.79 mg-Hg/Mg-ASR for elemental Hg and 6.8 mg-Hg/Mg-ASR for reactive Hg. Using these emission factors, total Hg emissions from ASR incineration were estimated as 2.2 kg/a. An ASR incineration plant investigated in this study used highly effective APCDs. Consequently, these emission factors might result in underestimation of national Hg emissions from ASR incineration. Emission factors estimated from lab-scale monitoring at a fabric filter outlet side might be more appropriate. However, even if emission factors calculated from plant-scale or the lab-scale monitoring are used, estimated emissions are still less than 1.0% of total Hg emissions in Japan. Therefore, Hg emissions from ASR incineration can be evaluated as insignificant. Unless Hg contents of ASR increase extremely, ASR incineration would be a minor source of Hg atmospheric emission in Japan, even if all ASRs were incinerated.     

An integrated analysis of air pollution from US coal-fired power plants

The United States is one of the world's leaders in electricity production, generating about 4116 billion kWh in 2021, of which coal accounted for 21.8% of the total. This study applies an integrated approach using both terrestrial and satellite data to specifically examine emissions from coal-fired power plants and its spatial extent. The study also highlights the effectiveness of government policies to reduce emissions. It was found that emission of pollutants from the country's energy sector has been steadily declining, with annual emissions of sulfur dioxide (SO₂) and nitrogen oxides (NO_x) decreasing from the US electric power sector between 1990 and 2020 by 93.4% and 84.8%, respectively, and carbon dioxide (CO₂) by 37% between 2007 and 2020. Although overall emissions from coal-fired power plants are declining, some individual plants have yet to install environmental equipment to control emissions. According to US government data, major emitters of SO₂, NO_x, and CO₂ in the US are the Martin Lake power plant in East Texas, the Labadie power plant near St. Louis, Missouri, and the James H Miller Jr plant near Birmingham, Alabama. This study also integrates TROPOMI satellite data to detect point emissions from individual power plants. While the highest levels of measured pollutants were over the country's major cities and areas of fossil fuel extraction, TROPOMI could clearly distinguish the pollution caused by power plants in more rural areas. Although the US has made great strides in reducing emissions from coal-fired power plants, these plants still represent a major source of pollution and remain a major concern. Totally eliminating coal as a power source will be difficult with the higher power demands resulting from the transition to electric automobiles.     

Assessment of the impact of biogenic VOC emissions in a high ozone episode via integrated remote sensing and the CMAQ model

In many metropolitan regions, natural sources contribute a substantial fraction of volatile organic compound (VOC) emissions. These biogenic VOC emissions are precursors to tropospheric Ozone (O₃) formation. Because forests make up 59% of the land area in Taiwan Province, China, the biogenic VOC emissions from forests and farmland could play an important role in photochemical reactions. On the other hand, anthropogenic emissions might also be one of the major inputs for ground level O₃ concentrations. Hence, emission inventory data, grouped as point, area, mobile and biogenic VOC sources, are a composite of reported and estimated pollutant emission information and are used by many air quality models to simulate ground level O₃ concentrations. Before using relevant air quality models, the emission inventory data generally require huge amounts of processing for spatial, temporal, and species congruence with respect to the associated air quality modeling work. The fist part of this research applied satellite remote sensing and geographic information system (GIS) analyses to characterize land use/land cover (LULC) patterns, integrating various sources of anthropogenic emissions and biogenic emissions associated with a variety of plant species. To investigate the significance of biogenic VOC emissions on ozone formation, meteorological and air quality modeling were then employed to generate hourly ozone estimates for a case study of a high ozone episode in southern Taiwan, which is the leading industrial hub on the island. To enhance the modeling accuracy, a unique software module, SMOKE, was set up for emission processing to prepare emission inputs for the U.S. EPA’s Models-3/CMAQ. An emission inventory of Taiwan, TEDS 4.2, was used as the anthropogenic emission inventory. Biogenic emission modeling was accomplished by BEIS-2 in SMOKE, with improvement of local LULC data and revised emission factors. Research findings show that the majority of biogenic VOC emissions occur in the mountainous areas and farmlands. However, the modeling outputs show that downwind of the most heavily populated and industrialized areas, these biogenic VOC emissions have less impact on air quality than do anthropogenic emissions.     

Computer simulated versus observed NO2 and SO2 emitted from elevated point source complex

ISC-AERMOD dispersion model was used to predict air dispersion plumes from an diesel power plant complex. Emissions of NO₂and SO₂from stacks (5 numbers) and a waste oil incinerator were studied to evaluate the pollutant dispersion patterns and the risk of nearby population. Emission source strengths from the individual point sources were also evaluated to determine the sources of significant attribution. Results demonstrated the dispersions of pollutants were influenced by the dominant easterly wind direction with the cumulative maximum ground level concentrations of 589.86 μg/m³ (1 h TWA NO₂) and 479.26 μg/m³ (1 h TWA SO₂). Model performance evaluation by comparing the predicted concentrations with observed values at ten locations for the individual air pollutants using rigorous statistical procedures were found to be in good agreement. Among all the emission sources within the facility complex, SESB-Power (diesel power plant) had been singled out as a significant source of emission that contributed >85% of the total pollutants emitted.     

Ambient nanoparticles/nanominerals and hazardous elements from coal combustion activity:Implications on energy challenges and health hazards

Coal is the most abundant fossil fuel in the world. Because of the growth of coal mining, coal-fired power plants and coal-burning industries, the increase of the emission of particulates(coarse, fine or ultrafine)is of great concern. There is a relationship between increasing human morbidity and mortality and progressive environmental air pollution caused by these types of particles. Thus, the knowledge of the physico-chemical composition and ambient concentrations of coal-derived nanoparticles will improve pollution control strategy. Given the current importance of this area of research, the advanced characterization of this coal combustion-derived nanoparticles/nanominerals as well as hazardous elements is likely to be one of the hottest research fields in coming days. In this review, we try to compile the existing knowledge on coal-derived nanoparticles/nanominerals and discuss the advanced level of characterization techniques for future research. This review also provides some of aspects of health risks associated with exposure to ambient nanoparticles. In addition, the presence of some of the hazardous elements in coal and coal combustion activities is also reviewed.     

煤基石墨烯原料与制备技术研究进展

作为21世纪的新兴碳纳米材料,石墨烯具有十分优异的性能,在众多领域中都展现出巨大的应用潜力。煤是储量最丰富、价格最低廉的碳源,且具有独特的结构和物质组成。将煤用于石墨烯等新型碳质材料及其复合材料的开发应用,是一项值得深入探索的工作。煤基石墨烯的发展既能促进煤的洁净利用也能提升煤炭资源的附加值。通过综述分析煤结构研究、煤石墨化机理以及煤基石墨烯研究与制备等方面的发展概况,并提出煤基石墨烯研究的现存问题和未来展望。认为,目前以煤为碳源制备石墨烯及其衍生物的研究尚属于起步阶段,研究的重点是在优化产品制备和性能的方面上,有关煤岩特性对产品质量影响的研究较少。原料煤的结构和物质组成的差异最终会影响煤基石墨烯产品的结构和性能,而煤的结构演变受地质因素影响显著。因此,未来煤基石墨烯的发展应该加强地质作用下的煤原始结构和物质组成对煤基石墨烯产品的影响研究,进而为加快煤基石墨烯研究和提高煤的清洁高效利用提供理论支撑。      

The quantification of atmospheric emissions from complex configuration sources using reverse dispersion modelling

Reverse dispersion modelling was employed to quantify sulphur dioxide (SO₂) and nitrogen dioxide (NO₂) emissions from brick firing clamp kilns and spontaneous combustion from a coal discard dump. Reverse dispersion modelling technique integrates ambient monitoring and dispersion simulation to calculate actual emission rates from an assumed rate of 1 g per second (g/s). Emission rates and emission factors were successfully quantified for SO₂, but not for NO₂, due to the influence of external sources and the complexity regarding the varying proportion of nitrogen oxides released from the kiln. Quantified emission factor for clamp kiln firing ranged from 1.91–3.24 g of SO₂ per brick fired and 0.67–1.14 g of SO₂ per kilogram of bricks fired. The variation in SO₂ emission factors was linked to high variability in energy input. The source configuration input to the dispersion model, assumed to represent the kiln, was changed from a volume source to a more effective “bi-point” source situated at the top of the kiln, with buoyancy calculated from the carbon combustion rate. In addition, SO₂ emission rate for spontaneous combustion from the discard dump was quantified as 0.35 g/s. 274 tons of discard material was estimated to burn annually, assuming that the emission rate is consistent over a year. Consequently, the reverse dispersion modelling and the elevated “bi-point” source technique may be considered a novel approach for quantifying emissions from combustion of materials or mixture of materials where knowledge of source parameters is limited.     

论煤地质学与碳中和

煤基碳排放构成了中国碳排放总量中最重要的部分,做好煤基碳减排和煤炭高效洁净低碳化利用是实现“碳中和”国家目标的重要途径,碳中和背景下的煤地质学发展值得关注。系统评述与碳中和相关的煤地质学研究领域,分析煤地质学在碳中和研究与工程实践中的作用和应用前景,探讨碳中和背景下煤地质学的重要发展方向。取得以下认识:推进清洁煤地质研究、服务煤的高效洁净化燃烧,勘探开发煤系天然气低碳燃料、优化一次能源结构和化石能源结构,开展煤化工资源勘查与开发地质保障研究、推动煤炭的低碳能源转化和新型煤化工产业发展,深化瓦斯地质研究、提高煤矿瓦斯（井下）抽采率、控制煤矿瓦斯的大气排放和泄漏,研究煤层甲烷天然逸散和煤层自燃排放、控制煤层露头的天然排放,发展煤层CO₂地质封存与煤层气强化开发（CO₂-ECBM）技术、推动碳捕获、利用与封存（CCUS）技术发展及其在火力电厂烟气碳减排中的商业化应用,研究煤炭勘查企业的碳足迹、实现企业净零排放,是与煤地质学紧密相关的碳减排技术路径;其中煤层甲烷与煤系气高效勘探开发、深部煤层CO₂-ECBM、煤层露头气体逸散与自燃发火控制、洁净煤地质与煤炭精细勘查是碳中和背景下煤地质学优先发展的重要领域。      

Assessment of greenhouse gas emissions from coal and natural gas thermal power plants using life cycle approach

The importance of mitigation of climate change due to greenhouse gas (GHG) emissions from various developmental and infrastructure projects has generated interest at global level to reduce environmental impacts. Life cycle assessment may be used as a tool to assess GHG emissions and subsequent environmental impacts resulting from electricity generation from thermal power plants. This study uses life cycle approach for assessing GHG emissions and their impacts due to natural gas combined cycle (NGCC) and imported coal thermal power plants using the IPCC 2001 and Eco-Indicator 99(H) methods in India for the first time. The total GHG emission from the NGCC thermal power plant was 584 g CO₂ eq/kWh electricity generation, whereas in case of imported coal, it was 1,127 g CO₂ eq/kWh electricity generation. This shows that imported coal has nearly ~2 times more impacts when compared to natural gas in terms of global warming potential and human health as disability-adjusted life years from climate change due to GHG emissions such as carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O).     

Ambient air quality of Kathmandu valley as reflected by atmospheric particulate matter concentrations (PM10)

This paper presents the analysis and interpretation of ambient particulate matter concentrations measured as PM₁₀ at a network of six air monitoring stations in Kathmandu valley during the years, 2003 through 2005. The purpose was to understand the pollution trends associated with different areas considering levels particulate matter concentrations representing the ambient air quality of Kathmandu valley. The study indicate that particulate concentrations (PM₁₀) measured are persistently higher at air sampling sites representing roadside areas compared to the background sites. The inter-station network variability with respect the particulate pollution suggests optimizing resources. The comparison of annual average PM₁₀ concentration observed at six air-monitoring sites in Kathmandu Valley with standard annual average concentration prescribed by World Health Organization as well as Europe Union indicates serious PM₁₀ pollution in Kathmandu valley.     

川渝地区煤的石墨化潜势研究

煤及煤系石墨化利用对于增强石墨矿产的战略保障能力、促进煤系矿产资源高效利用和推动煤炭企业转型升级等均具有重要意义。在能源矿产改革转型的关键时期,为了厘清川渝地区煤的石墨化潜势,在梳理分析煤的石墨化、煤基碳材料前驱体选择和川渝地区煤田地质概况的基础上,通过对川渝地区主要赋存煤类、煤质和显微组分特征的分析,从影响煤石墨化的内在因素和煤基碳材料的需求出发,采用主成分分析法探讨了川渝地区煤基碳材料前景和煤系石墨资源赋存潜力。结果表明:研究区煤的显微组分以镜质组为主,低灰、低硫,演化程度更高的无烟煤更易于石墨化,煤石墨化后的产物则是制备碳材料的极佳前驱体;根据主成分分析的定量评价结果,可将川渝地区煤系石墨资源潜力区带划分为Ⅰ级优势区、Ⅱ级良好区和Ⅲ级潜力区。四川雅安?攀西Ⅰ级区带三叠系上统须家河组煤具有变质程度高、低灰、低硫特征,龙门山构造岩浆带是煤石墨化的外在条件,是煤系石墨矿产资源优势赋存区和制备煤基碳材料的优选资源;渝东北Ⅱ级区带和渝东南Ⅱ级区带具有构造条件复杂、煤演化程度高的特点,为煤系石墨资源赋存良好区;南桐松藻Ⅲ级区带和四川芙蓉?古叙Ⅲ级区带则为煤系石墨资源的潜力区。煤系石墨的潜力研究是能源矿产由粗放型利用向高端新型材料精细化应用转变的重要桥梁,为实现煤炭资源高价值、绿色开发利用提供了指导方向。      

Emissions of greenhouse and non-greenhouse air pollutants from fuel combustion in restaurant industry

Information on emissions from restaurant industry is limited in scientific literature. Emission inventory of greenhouse and non-greenhouse air pollutants from restaurant industry was prepared for two Class 1 Indian cities, viz. Nagpur and Raipur for 2010. Emissions were estimated from a primary database on type and amount of cooking fuel combusted in restaurant industry in the selected cities. Liquefied petroleum gas, charcoal, wood, coal, diesel and candy coal are used in this industry, first three being the major ones. Carbon dioxide emission was highest in both cities and liquefied petroleum gas, charcoal and wood were the major contributors to emissions. Total annual emissions of greenhouse gases, viz. carbon dioxide, methane and nitrous oxide were estimated to be 19,251, 27 and 1 Mg year^?1 in Nagpur and 21,207, 34 and 1 Mg year^?1 in Raipur, whereas total annual emissions of non-methane hydrocarbon (NMHC), carbon monoxide, total suspended particulate (TSP), sulphur dioxide, nitrogen oxides and black carbon (BC) were 96, 959, 31, 12, 19, 3 Mg year^?1 and 87, 1141, 78, 37, 28, 6 Mg year^?1 in Nagpur and Raipur, respectively, from all the fuels used in restaurant industry. Considering the huge growth of Indian restaurant industry in the last decade and the predicted growth in future, emissions from this industry is assumed to grow and will play a major role in governing regional and national emissions in India.     

我国煤系石墨研究及资源开发利用前景

煤系石墨属于特殊的非典型晶质矿物,多为隐晶质石墨,既是石墨矿产的重要组成部分,也是煤系综合矿产的一种。煤系石墨与煤层为同层异矿,煤向石墨演化的实质在元素组成上表现为富碳、去氢和脱氧,在分子结构上表现为有序化增强和石墨晶体结构的逐渐形成。煤岩组分、岩浆热和地质构造等均对煤成石墨化作用具有重要的影响,在多因素综合作用下,煤系石墨成矿常表现出差异石墨化特征。从煤系石墨成矿机理入手,提出了以化学组成参数为基础指标,以结构参数为精确指标的煤系石墨鉴别指标体系;从资源评价需求出发,将不同演化程度的煤系石墨划分为Ⅰ级（石墨）、Ⅱ级（半石墨）和Ⅲ级（石墨化无烟煤）等3类。煤系石墨的形成与岩浆活动和挤压性构造环境密切相关,受区域性构造-岩浆带控制,煤系石墨分布具有方向性、递变性、集中成带的特点,成矿区带呈现出“一纵三横”的分布特点,划分为滨太平洋成矿域、南岭成矿域、秦岭-大别山成矿域和阴山-燕山成矿域和9个成矿带。分析了我国煤系石墨资源现状,指出由于我国煤炭资源丰富和赋煤区构造-热叠加作用显著,煤系石墨资源潜力巨大。煤系石墨开发利用对于增强石墨矿产的战略保障能力、促进煤系矿产资源合理开发利用和推动煤炭企业转型升级等均具有重要意义。分析了当前煤系石墨矿产资源开发利用方面存在的问题,提出了相应的政策建议。      

Assessment of elemental content of milled coal,combustion residues,and stack emitted materials: Possible environmental effects for a Canadian pulverized coal-fired power plant

Two monitoring studies were carried out at four-year intervals on a power plant that uses western Canadian subbituminous coal and generates approximately 800 Mw/h of electricity. The distributions of elements of environment concern (As, Hg, Ni, Pb, and Cd) and elements of environmental interest (B, Ba, Be, Cl, Co, Cr, Cu, Mn, Mo, Th, Se, V, U, and Zn) in milled coals, power plant ashes, and emitted materials from the stack were determined using neutron activation analysis (NAA), Inductively Coupled Plasma Emission Spectroscopy (ICPES), and Inductively Coupled Plasma-Mass spectroscopy (ICP-MS) for most elements, Graphite Furnace Atomic Absorption (GFAA) for Pb, and Cold Vapor Atomic Absorption (CVAA) for Hg.The concentrations of most of elements in milled coal are low as compared to world coals and other Canadian milled coals. For example, in both studies mercury is within the lower range of world coal. Bottom ashes from both studies have low concentrations of As, Cd, Hg, Pb, and Zn, as well as low relative enrichment factors (RE) for the same elements, indicating that they were not enriched in the bottom ash. The ESP's remove most of the elements of environmental interest as indicated by their high RE ratios of greater than > 0.7.The rates of input of elements of environmental concern (As, Cd, Hg, Pb and Ni) for this station were 23.65, 1.24, 0.54, 98.2 and 95.2 kg/day, respectively, of which only 0.20, 0.02, 0.31, 0.48 and 0.36 kg/day were emitted from the stack. Thus only a small amount of these elements found in the milled coal was emitted while most were captured in the bottom and the ESP ashes. Nickel has the highest rate of emission (0.48 kg/day) within the elements of environmental concern group. However, the Ni emitted from this station does not belong to the toxic species. The element with the lowest rate of emission is Cd (0.02 kg/day). The total emission of elements of environmental concern is 1.37 kg/day, which is low as compared their ambient concentrations in either rural or urban air. The total rate of emission of B, Ba, Be, Co, Cr, Cu, Mn, Mo, Se, Th, U, V, and Zn is 56.51 kg/day and is mostly comprised of the total emission of Ba (21.73 kg/day) and Zn (19.14 kg/day).     

中国煤炭甲烷管控与减排潜力

甲烷是最主要的非二氧化碳温室气体,受到越来越多的重视。煤炭甲烷是我国最主要的甲烷排放源类型,我国也是世界煤炭甲烷排放量最大的国家,煤炭甲烷的有效排放管控与高效开发利用兼具温室气体减排、能源气体开发利用和灾害气体防治三重意义。基于系统调研和研究工作积累,概述了煤炭甲烷排放管控背景,总结了全球与代表性国家煤炭甲烷排放及其管控现状,阐释了我国煤炭甲烷开发利用与排放管控历程及发展趋势,讨论和前瞻了我国煤炭甲烷减排路径与减排潜力。已有研究工作表明:我国煤炭甲烷排放主要来自煤炭地下开采风排瓦斯,且较长时期内仍是我国煤炭甲烷的主要来源;随着我国关闭矿井增多,由此产生的关闭矿井甲烷排放量呈增长趋势,是我国煤炭甲烷不容忽视的来源。随着碳中和目标的提出,温室气体减排的政策导向逐渐成为我国煤炭甲烷排放管控的重点,明确了煤炭甲烷减排方向。我国煤炭甲烷排放管控形成了以煤层气勘探开发利用、煤矿瓦斯抽采利用、关闭/废弃矿井瓦斯抽采利用、乏风瓦斯利用等全浓度利用,煤炭采前、采中和采后全周期利用为特征的关键技术路径。我国煤炭甲烷排放管控面临巨大压力和严峻挑战,诸多政策、机制、技术问题亟待破解。突破复杂地质条件适配性煤层...     

Multi-peril risk assessment for business downtime of industrial facilities

The chemical industry is one of the most important industry sectors in terms of energy consumption and CO₂ emissions in China. However, few studies have undertaken accounting of the CO₂ emissions in the chemical industry. In addition, there are some shortcomings in the traditional accounting method as a result of poor data availability, such as the incomplete consideration of emission sources and overestimation of actual emissions. Based on the traditional accounting method and the actual situation of the chemical industry, this study proposes a method called the Emission Accounting Model in the Chemical Industry, which covers fossil energy-related emission, indirect emission generated by electricity and heat, carbonate-related process emission and the reuse of CO₂. In particular, fossil energy used as feedstock is included. By applying the Emission Accounting Model in the Chemical Industry in China, the calculated CO₂ emissions would be 19–30% less than the result from the traditional method. In addition, it is found that the indirect CO₂ emissions generated by electricity and heat account for 67% of the total amount, the fossil energy-related emissions account for approximately 37%, the process-related emissions accounted for 2%, and reuse of CO₂ accounts for ??6% in 2016. The production of ammonia, ethylene and calcium carbide generated approximately half of the total CO₂ emissions in 2016. In addition, in view of emission sources and carbon source flow, two other bottom-up accounting methods are proposed that can take effect when the chemical plant-level data are available.

     

Serviceability-related reliability for mainshock-damaged reinforced concrete piers considering the aftershock-induced seismic hazards

To investigate the impact of carbon emission reduction paths on energy demand and CO₂ emissions in China, in this study, quantitative carbon emission reduction paths in the period 2014–2020 are established by decomposing the target for emissions reduction. An optimization model of energy demand, into which reduction paths are incorporated, is then constructed from a goal-oriented perspective. The results suggest that energy consumption varies under different emission reduction paths. Coal demand is found to be much more sensitive to the choice of emission reduction path than other forms of energy; in particular, it responds strongly to the decreasing reduction path. We conclude that the decreasing reduction path is a better means than the increasing reduction path of achieving China’s emission reduction target for 2020 with the least amount of energy and the least amount of CO₂ emissions.     

Assessing the technology impact for industry carbon density reduction in China based on C3IAM-Tice

Thermal power, steel, cement, and coal chemical industries account 62.6% energy consumption and 84.6% carbon emissions of China simultaneously in 2015. This research use C³IAM-Tice model to analyze the impact of advanced technologies ratio increasing quantitatively. The model can explore the balance of emission reduction and economy efficiency of energy use, finally got the technology structure optimization for these four industries. The paper uses the historical energy consumption and CO₂ emission, combing with the low-carbon developing goal objection, to create the database for these four energy- and carbon-intensive industries. As the result, the scenario-4, which is the most advanced technology-oriented strategy, shows 282 Mt CO₂ emission reductions for the 2020 Goal. In this scenario, 26.19%, 47.43%, 65.39%, and 28.98% of the CO₂ emissions per unit of added value in thermal power industry, steel industry, cement industry, and coal chemical industry could be reduced comparing with data in 2005. Although the advanced technology-oriented strategy shows the positive impact, we need to consider the cost of elimination of existed technology. On the other hand, the paper notices the future technology, with new energy alternative, low-carbon economy development, and industry restructure together, which are important factors for the low-carbon development of China.

     

Estimation of atmospheric iodine emission from coal combustion

Coal combustion is the primary anthropogenic source of atmospheric iodine, which has important environmental and health effects. The iodine distribution in Chinese coals and the atmospheric iodine emission factors of coal-fired boilers are studied to estimate the iodine atmospheric flux from coal combustion in China from 1995 to 2009. The national average iodine content weighted by coal yield fluctuated from 2.61 mg kg^-1 in 1995 to 2.09 mg kg^-1 in 2009, recording an annual decline of 1.42 %. By establishing a monitoring program, iodine distribution in coal by-products after the coal is consumed in combustors is measured, and atmospheric iodine emission factors by sectors are calculated. Based on the coal consumption by sectors, the annual atmospheric iodine emission from coal combustion in China increased at an annual rate of 4.3 % from 3031.1 tons in 1995 to 4872.6 tons in 2009. Anthropogenic atmospheric iodine emission is significantly underestimated, and its environmental and health effects must be given more attention.