浅论石油化工企业二氧化硫总量减排

为满足石油化工企业总量控制的要求,采取相应的治理措施,降低污染物排放总量,避免采取大量投资和占地的末端治理措施,在工艺过程中采取措施降低主要污染物排放总量是行之有效的途径,采用催化工艺中添加硫转移脱氮剂的办法、热电厂锅炉采用改善炉体燃烧状态、配合石灰石脱硫等工艺过程措施,探讨进一步减少二氧化硫排放总量的可行性。     

新疆某伴生放射性钒矿氡浓度水平调查及防治措施的探讨

在伴生矿的勘探、开采过程中,如果井下工作场所通风不足,矿石、土壤和岩石等所释放的氡气会造成局部的放射性污染,因此了解伴生矿矿井中氡气的水平并探讨有效的防护措施是非常必要的。本文就新疆某矾矿在矿井建设初期和通风设施建成后两时间段的氡浓度水平及防治措施进行探讨,并提出相应的防护措施和建议。     

西宁市大气降水酸度监测与分析

大气降水的酸化是当今世界面临的重大环境问题之一,它主要是指工业、生活和交通运输工具所产生的硫氧化物(SO_x)和氮氧化物(NO_x)释放进入大气后,在云雾的吸收和降水的洗脱作用下,经复杂的物理、化学变化而形成酸性降水(简称酸雨)(pH< 5.6的天然降水)。酸性降水可以对环境造成长期有害的影响,它包括土壤的酸化和脱矿质作用;对森林和地面建筑物的损坏;对湖泊、河流、地下水水体的酸化,其后果是损害鱼类和水生生态系统,以及饮用水质量的改变等。这些影响都是由于长期累积或短时段最大酸雨事件所造成的。鉴于酸雨对环境造成的严重危害,根据西宁市大气污染逐年加重的情况,1990年,我站在西宁市开展了系统的大气降水监测工作,初步掌握了西宁市降水水质现状及其形成原因,现介绍如下。     

川东地区气田水水质特性研究

气田水是天然气开采过程中采出的地层水,因其来源广泛、类型众多以及成分复杂等原因导致其很难达标处理,且容易对土壤、地表水以及地下水造成污染。因此,本文以川东地区气田水为研究对象,通过常规水质分析和GC-MS等技术手段对其进行全面分析,结果表明：①川东地区气田水特征污染物为氯化物、COD、SS、阴离子表面活性剂以及硫化物等物质;②根据其水质特性可以将川东地区气田水分为两类,一类是高矿化度、高含有机物气田水;另一类是高含硫、高含有机物气田水;③川东地区气田水中共有17种有机污染物,主要为烷烃类、醇类、酯类以及少量酸类等物质。     

川东地区气田水水质特性研究

气田水是天然气开采过程中采出的地层水,因其来源广泛、类型多以及成分复杂,导致难达标处理且易对土壤、地表水以及地下水造成环境污染。文章以川东地区气田水为研究对象,通过常规水质测定和气相色谱-质谱联用(GC-MS)检测等方法对其进行全面分析,结果表明:川东地区气田水的特征污染物为氯化物、COD、SS、阴离子表面活性剂以及硫化物等物质;根据其水质特性可以将川东地区气田水分为两类,一类是高矿化度、高含有机物气田水,另一类是高含硫、高含有机物气田水;川东地区气田水中共有17种有机污染物,主要为烷烃类、醇类、酯类以及少量酸类等物质。     

蜂窝煤中硫和灰分的测定

常见的空气污染物有总悬浮颗粒物、二氧化硫、氮氧化物、氧化碳和苯并芘等.它们在一定条件下还可形成二次污染,造成更严重危害.燃烧是烟尘和SO2的主要排放源.为此,本文对北京5个城区74块煤中硫和灰分的含量进行了测定.测定结果如下蜂窝煤中水分含量为3.4%～10.6%,超标者6.8%,其余含水量正常;全硫含量为0.2%～0.4%,北京市地方标准DB 11/097-1998＜低硫优质煤及制品中规定煤中的全硫值≤0.5%,说明符合标准;灰分含量为25%～35%(无规定标准).1个月中燃煤含硫量的连续测定值为0.2%～0.4%,表明北京地区对高硫煤的控制卓有成效.在煤样中添加一定量的秸秆粉、CaCO3粉和粘合剂,含硫量平均值为0.18～0.28%,灰分为25.5～27.4%.实验表明固硫效果显著.     

石油污染土壤植物修复的影响因素

为修复石油开采工艺过程中对环境土壤造成的污染,对植物修复土壤方法进行盆栽实验。采用紫花苜蓿和多花黑麦草两种植物,对油田固体污染物进行植物修复实验,并考察石油污染土壤的不同比例系数稀释对比和紫花苜蓿、多花黑麦草两种不同科类植物的修复效果。研究结果表明:紫花苜蓿、多花黑麦草对重金属的富集迁移效果明显,提高了生物可利用性,降低了土壤毒理性。     

我国酸雨污染及其控制规划构想

针对我国酸雨污染比较严重的情况,从可持续发展角度提出了控制我国酸雨污染的各种方法和手段,并根据我国的致酸污染物主要是煤炭燃烧产生的实际情况,从煤炭生命周期入手,提出了包括“无行动方案”、“替代方案”、“清洁生产工艺”等控制措施。     

洁净煤──中国能源的未来

煤是当今世界能源结构中仅次于石油而居第二位的重要能源，在我国的能源结构中居第一位。1994年我国的煤炭产量达12．l亿吨，是世界上最大的煤炭生产国消费国。我国煤炭资源丰富，在未来3（y50年或更长的时间里，以煤为主的能源结构不会改变。但是，煤本身存在许多弱点，除开采运输不便、热值较低外，更为重要的是燃烧过程中会排放二氧化硫、二氧化碳、氢氧化物、粉尘等有害气体和物质，污染大气，产生酸雨，危害社会。为此，世界上许多国家大力开展洁净煤技术的研究，从煤燃烧前、燃烧过程中和燃烧后进行净化处理，将煤液化或气化，已取得…     

《“钻井废弃物不落地达标处理技术”适用性研究》项目完成

钻井废弃物主要是指废弃钻井泥浆、钻井废水和钻屑等混合物的总称。钻井泥浆（即钻井液）是石油气钻井过程中以其多种功能满足钻井工作所需的各种循环流体,用于石油勘探、钻井、开采等工艺过程,主要起到携带、悬浮钻屑,稳定井壁,平衡地层压力,冷却、润滑钻头钻具的作用。其中含有大量的无机盐、高分子量的有机化合物、某些重金属离子（如汞、砷、Cd、铬、铅等）。这些污染物有的来自钻井液化学添加剂,有的是从地层中携带而来。若不加处理长期存储或掩埋,这些有害物质会对土壤、地表水、地下水造成污染,直接或间接影响人类生态环境。     

National benefits,local costs? Local residents' views on environmental and social effects of large‐scale mining in Chingola,Zambia

This study examined the environmental and social effects of large‐scale mining in Chingola, Zambia. Data was collected through semi‐structured interviews with 164 residents living close to Zambia's largest open pit mine, key informants and desk analysis of secondary data. Quantitative data was analysed using the chi‐square test, one sample T‐test and two sample Z‐proportions test, while qualitative data was analysed using content analysis. Results show that the residents reported being most affected by sulphur dioxide air emissions and noise pollution due to the proximity of the copper smelter and heavy moving machinery to their residences. The residents received domestic water containing rust and copper ore particles from the water utility company which draws raw water from the mine. Although the mine was a source of employment for locals, over 4,000 jobs (representing a 33% decrease) have been lost over a period of 4 years, negatively affecting the local economy. Mine management attributed the job losses to high production costs and mechanization of mining processes. The residents perceived the job losses to have led to crime, alcohol abuse and prostitution among youths as well as a general increase in poverty levels. Analysis of air emissions data from the mine found elevated levels of dust, cadmium, copper and lead pollutants. Key informants from Nchanga Mine reported implementing bioremediation to reduce soil contamination by the heavy metals and recycling SO₂ to produce sulphuric acid. The study recommends an increase in social corporate responsibility from the mine management to ensure residents derive more substantive benefits from their proximity to the mine.     

碱锰型电解二氧化锰生产环境影响与环保措施

主要以某公司9000t/a碱锰型电解二氧化锰技改项目环境影响评价为例,结合验收监测数据,简要介绍碱锰型电解二氧化锰生产的环境影响与环保措施.该公司采用氧化锰矿和硫铁矿混合硫酸溶液浸出--电解的生产工艺生产碱锰型电解二氧化锰,生产过程中大气污染源主要有锅炉排放的烟气,化合、电解工序产生的硫酸雾;生产废水主要有锅炉除尘废水、漂洗水及炭黑生产废水;废渣主要是压滤锰渣.     

Characteristics of coal mine ventilation air flows

Coal mine methane (CMM) is not only a greenhouse gas but also a wasted energy resource if not utilised. Underground coal mining is by far the most important source of fugitive methane emissions, and approximately 70% of all coal mining related methane is emitted to the atmosphere through mine ventilation air. Therefore, research and development on mine methane mitigation and utilisation now focuses on methane emitted from underground coal mines, in particular ventilation air methane (VAM) capture and utilisation. To date, most work has focused on the oxidation of very low concentration methane. These processes may be classified based on their combustion kinetic mechanisms into thermal oxidation and catalytic oxidation. VAM mitigation/utilisation technologies are generally divided into two basic categories: ancillary uses and principal uses. However, it is possible that the characteristics of ventilation air flows, for example the variations in methane concentration and the presence of certain compounds, which have not been reported so far, could make some potential VAM mitigation and utilisation technologies unfeasible if they cannot cope with the characteristics of mine site ventilation air flows. Therefore, it is important to understand the characteristics of mine ventilation air flows. Moreover, dust, hydrogen sulphide, sulphur dioxide, and other possible compounds emitted through mine ventilation air into the atmosphere are also pollutants. Therefore, this paper presents mine-site experimental results on the characteristics of mine ventilation air flows, including methane concentration and its variations, dust loadings, particle size, mineral matter of the dust, and other compounds in the ventilation air flows. The paper also discusses possible correlations between ventilation air characteristics and underground mining activities.     

基于产业链分析的长三角地区CO2与大气污染物排放研究

长三角地区作为我国大气污染较为严重区域之一,如何在保持经济增长的同时减少CO₂与大气污染物的排放已成为一个重要挑战。本研究基于2007年与2012年长三角区域间投入产出表,定量分析了长三角地区省市间贸易引致的二氧化碳和大气污染物排放转移特征和变化趋势。同时,运用产业关联系数法,从前向关联与后向关联双重视角分析了长三角地区减缓CO₂和大气污染物排放的关键行业。研究结果表明,长三角的SO₂、PM_2.5排放总量表现为消费端大于生产端,CO₂、NO_x排放总量表现为生产端大于消费端。安徽省总体呈现为长三角地区贸易的SO₂、NO_x与PM_2.5排放净调出地,而上海与浙江表现为多数污染物排放净调入地。CO₂与大气污染物协同前向减排的关键行业为江苏省、浙江省和安徽省的电力、热力的生产和供应业,安徽省的煤炭开采和洗选业等,可以通过生产端技术革新和能源结构优化来促进减排;CO₂与大气污染物后向协同减排的关键行业为江苏省、浙江省和安徽省的建筑业等,对于这些行业,调整消费结构是有效的减排措施。为更好地制定长三角地区减排与污染防治政策,应当综合考虑行业减排、协同减排等,以确保经济持续增长的同时达到减排目标。     

Technological reviews of particulate matter and their source identification techniques

Particulate matter (PM) is one of the primary pollutants produced from mining operations. This paper summarizes the existing techniques used to identify sources of PM and their contribution to ambient air pollution. Human health studies indicate that there is an association between airborne PM and adverse health effects. Particularly in coal mining areas, the burning of coal and PM from machinery operations cause low air quality that is physically harmful. Thus, the sources of smoldering combustion, that are typical in coal mine burns, increase the risk to mine workers who are exposed to high concentrations of known toxicity associated with PM. Recent studies on the modeling of PM concentration profiles across various sources were reviewed for this paper.     

A novel process integration,optimization and design approach for large-scale implementation of oxy-fired coal power plants with CO2 capture

The widespread use of fossil fuels within the current energy infrastructure is considered as the largest source of anthropogenic emissions of carbon dioxide, which is largely blamed for global warming and climate change. At the current state of development, the risks and costs of non-fossil energy alternatives, such as nuclear, biomass, solar, and wind energy, are so high that they cannot replace the entire share of fossil fuels in the near future timeframe. Additionally, any rapid change towards non-fossil energy sources, even if possible, would result in large disruptions to the existing energy supply infrastructure. As an alternative, the existing and new fossil fuel-based plants can be modified or designed to be either “capture” or “capture-ready” plants in order to reduce their emission intensity through the capture and permanent storage of carbon dioxide in geological formations. This would give the coal-fired power generation units the option to sustain their operations for longer time, while meeting the stringent environmental regulations on air pollutants and carbon emissions in years to come.Currently, there are three main approaches to capturing CO₂ from the combustion of fossil fuels, namely, pre-combustion capture, post-combustion capture, and oxy-fuel combustion. Among these technology options, oxy-fuel combustion provides an elegant approach to CO₂ capture. In this approach, by replacing air with oxygen in the combustion process, a CO₂-rich flue gas stream is produced that can be readily compressed for pipeline transport and storage. In this paper, we propose a new approach that allows air to be partially used in the oxy-fired coal power plants. In this novel approach, the air can be used to carry the coal from the mills to the boiler (similar to the conventional air-fired coal power plants), while O₂ is added to the secondary recycle flow as well as directly to the combustion zone (if needed). From a practical point of view, this approach eliminates problems with the primary recycle and also lessens concerns about the air leakage into the system. At the same time, it allows the boiler and its back-end piping to operate under slight suction; this avoids the potential danger to the plant operators and equipment due to possible exposure to hot combustion gases, CO₂ and particulates. As well, by integrating oxy-fuel system components and optimizing the overall process over a wide range of operating conditions, an optimum or near-optimum design can be achieved that is both cost-effective and practical for large-scale implementation of oxy-fired coal power plants.     

Study on assessment of slope stability and mixed disposal of overburden in voids of Singrauli Coalfield

The mining industry can be considered the backbone of the Indian economy as well as facilitating the power that drives most of the other industries in the company. The overburden and waste rocks produced during coal mining are major concerns in regard to the amount of land that is required for their disposal, as well as the stability of dumps for these materials, which are of increasing height. Land reclamation issues are also a concern. In this work the adverse impacts caused by the dumping of overburden on land and acidic mine water on water bodies is discussed. Remote sensing tools were used along with the laboratory experimentation to assess the various impacts. This study also shows that silt released from waste dumps, can affected the angle of repose of the overburden dump slope. The angle of repose of the overburden materials varies with particle size composition. Thus, use of in‐pit crushers in large opencast mining operations can effectively reduce the area locked under the waste dumps. The acid neutralization potential of fly ash and overburden for the treatment of acid water was tested in the laboratory by using fly ash and waste rock materials on acidic coalfield water. The results are encouraging, and fly ash may prove to be a good acid neutralizer when used in conjunction of coal overburden material.     

Acid Deposition and Integrated Zoning Control in China

China's rapidly growing economy is coupled with the consumption of large amounts of coal. An energy mix dominated by coal and inefficient energy utilization processes have led to increasingly serious problems of acid rain and sulfur dioxide pollution. Moreover, trends in the emissions of acidifying air pollutants lead to predictions of a very serious acid deposition problem in the future. In the absence of mitigating actions, these trends foretell a future of increasingly detrimental impacts to ecosystems in China and, potentially, to ecosystems in neighboring countries. China has implemented a two control zone (TCZ) policy, resulting in the establishment of acid rain and sulfur dioxide control zones, in an attempt to implement a cost-effective approach to mitigating acid deposition problems. While some short-term successes have resulted from management actions associated with the TCZ policy, it is clear additional measures and new policy directions are needed to reverse worsening acid deposition problems in the long term. To this end the following recommendations are presented: adjusting the primary energy mix, placing a greater emphasis on abating the effects of acid deposition, concentrating pollution control on large point sources, implementing an emission permit system for coal-fired power plants, utilizing an integrated approach in designing and evaluating control measures, and developing a greater research capacity. Research strategies must be developed that will lead to: (1) an improved scientific understanding of the sources of acidifying pollutants, their associated migration patterns, and their impacts; and (2) an identification of cost-effective mitigating strategies for the entire country.     

Oxy-fuel coal combustion—A review of the current state-of-the-art

Carbon dioxide emissions will continue being a major environmental concern due to the fact that coal will remain a major fossil-fuel energy resource for the next few decades. To meet future targets for the reduction of greenhouse gas (GHG) emissions, capture and storage of CO₂ is required. Carbon capture and storage technologies that are currently the focus of research centres and industry include: pre-combustion capture, post-combustion capture, and oxy-fuel combustion. This review deals with the oxy-fuel coal combustion process, primarily focusing on pulverised coal (PC) combustion, and its related research and development topics. In addition, research results related to oxy-fuel combustion in a circulating fluidised bed (CFB) will be briefly dealt with.During oxy-fuel combustion, a combination of oxygen, with a purity of more than 95 vol.%, and recycled flue gas (RFG) referred to as oxidant is used for combusting the fuel producing a gas consisting of mainly CO₂ and water vapour, which after purification and compression, is ready for storage. The high oxygen demand is supplied by a cryogenic air separation process, which is the only commercially available mature technology. The separation of oxygen from air as well as the purification and liquefaction of the CO₂-enriched flue gas consumes significant auxiliary power. Therefore, the overall net efficiency is expected to be decreased by 8–12% points, corresponding to a 21–35% increase in fuel consumption. Alternatively, ion transport membranes (ITMs) are proposed for oxygen separation, which might be more energy efficient. However, since ITMs are far away from becoming a mature technology, it is widely expected that cryogenic air separation will be the selected technology in the near future. Oxygen combustion is associated with higher temperatures compared with conventional air combustion. Both fuel properties as well as limitations of steam and metal temperatures of the various heat exchanger sections of the boiler require a moderation of the temperatures in the combustion zone and in the heat-transfer sections. This moderation in temperature is accomplished by means of recycled flue gas. The interdependencies between the fuel properties, the amount and temperature of the recycled flue gas, and the resulting oxygen concentration in the combustion atmosphere are reviewed.The different gas atmosphere resulting from oxy-fuel combustion gives rise to various questions related to firing, in particular, with respect to the combustion mechanism, pollutant reduction, the risk of corrosion, and the properties of the fly ash or its resulting deposits. In this review, detailed nitrogen and sulphur chemistry was investigated in a laboratory-scale facility under oxy-fuel combustion conditions. Oxidant staging succeeded in reducing NO formation with effectiveness comparable to that typically observed in conventional air combustion. With regard to sulphur, a considerable increase in the SO₂ concentration was measured, as expected. However, the H₂S concentration in the combustion atmosphere in the near-flame zone increased as well. Further results were obtained in a pilot-scale test facility, whereby acid dew points were measured and deposition probes were exposed to the combustion environment. Slagging, fouling and corrosion issues have so far been addressed via short-term exposure and require further investigation.Modelling of PC combustion processes by computational fluid dynamics (CFD) has become state-of-the-art for conventional air combustion. Nevertheless, the application of these models for oxy-fuel combustion conditions needs adaptation since the combustion chemistry and radiative heat transfer is altered due to the different combustion gas atmosphere.CFB technology can be considered mature for conventional air combustion. In addition to its inherent advantages like good environmental performance and fuel flexibility, it offers the possibility of additional heat exchanger arrangements in the solid recirculation system, i.e. the ability to control combustion temperatures despite relatively low flue gas recycle ratios even when combusting in the presence of high oxygen concentrations.     

Coal energy conversion with carbon sequestration via combustion in supercritical saline aquifer water

The standard idea for deep saline aquifer sequestration is to separate carbon dioxide from a process stream, compress it, and inject it underground. However, since carbon dioxide is less dense than water, even at the high pressures found in aquifers, it is buoyant and will move towards the surface unless trapped by an impermeable seal. Also, significant energy expenditure is required to separate and compress carbon dioxide, even though neat carbon dioxide is not a desired product. These issues may be addressed by combining the idea of fast dissolution at the surface with supercritical water oxidation (SCWO). By burning coal at high pressure in supercritical water drawn from an aquifer, and then sequestering the entire pre-equilibrated effluent, all carbon from the fuel is captured, as well as all non-mineral coal combustion products including sulfur and metals.A possible block diagram of an SCWO-based electric power plant is proposed, including processes to handle salts from the aquifer brine and minerals from coal. The plant is thermodynamically modeled, using an indirectly fired combined cycle to convert energy from hot combustion products to work. This model estimates the overall thermal efficiency that can be achieved, and reveals unanticipated interactions within the plant that have significant effects on efficiency. The assumptions and results of the model highlight design challenges for an actual system.