大型水煤浆锅炉工业污染特点及其控制

结合国内最大容量的670 t/h水煤浆锅炉的运行情况,介绍了水煤浆燃料及其燃烧方面的一些特点,并进行了相关的分析和探讨,说明水煤浆对于环境保护,尤其是经济相对发达地区的环境保护,确实具有积极意义.同时,针对大容量水煤浆锅炉出现的新的污染问题,也提出了进一步的解决措施.     

应用水煤浆洁净燃烧技术控制燃煤工业锅炉SO2污染--中国燃煤工业锅炉SO2污染综合防治对策(五)

研究了水煤浆洁净燃料及其在燃煤工业锅炉上控制SO2污染的应用。主要内容包括水煤浆洁净燃烧技术概况，生产方法、分类及其物理性能，燃烧系统的工艺过程及其技术性能，水煤浆锅炉的特点及经济效益。研究表明：水煤浆洁净燃烧技术燃烧效率高，燃尽率高，炉渣含碳量低，烟尘和SO2排放浓度低。水煤浆洁净燃烧技术是燃煤工业锅炉理想的替代技术。     

造纸“三废”联合烟气治理技术

结合华丰纸业有限公司和轻华热电有限公司的生产实际，介绍了利用造纸废浆、废渣掺入煤中进行炉内脱硫，废水喷入烟道进行炉后脱硫的联合治理技术，并进行了效益分析。     

青山热电厂200 MW燃煤机组RCFB烟气脱硫装置的特点

RCFB是一种已经在工程中得到成功应用的烟气脱硫技术。以湖北青山热电厂“油改煤”二期工程200MW燃煤机组RCFB烟气脱硫装置为依托，对其特点进行了较为全面的介绍。     

煤浆洗涤法去除烟气中的SO2

分别以高硫原煤、低硫原煤和中煤配制的煤浆作为洗涤介质,去除烟气中的SO2。反应温度高于40℃时,采用高硫原煤煤浆洗涤烟气,SO2去除率在90％以上;O2含量对SO2去除率影响不大;SO2去除率随其含量的增加而降低。低硫原煤煤浆同样可用于烟气脱硫,随温度的升高,煤浆pH的降低幅度和SO2去除率均增大,与用高硫原煤时的情况类似。中煤煤浆亦能有效去除烟气中的SO2,反应过程中煤浆pH的降低对SO2去除率的影响不大。在烟气脱硫的同时,3种煤中的黄铁矿均被不断浸出,浸出铁质量浓度随反应时间的延长和SO2去除率的增大而增加。     

湿法脱硫石膏弃浆与煤灰浆混合排放试验研究

通过华能珞璜电厂现场水质测试和实验室模拟生垢试验研究，认为该厂脱硫石膏浆与煤灰浆混合后的结垢成分以氢氧化镁为主，将脱硫弃浆引入水力输灰系统将可大大降低输灰管的结垢速率。     

水煤浆洁净燃烧技术在南海发电一厂的工程应用与分析

简要介绍了水煤浆的特点及其在广东南海发电一厂的应用,分析了水煤浆洁净燃烧技术的应用在减少SO2排放量及环境保护方面的意义。     

洗精煤混合磨矿制浆工艺

东庞矿水煤浆厂一期工程于1999年底建成，一期设计生产能力为年产水煤浆15～18万t。水煤浆厂建成投产后，技术人员依靠自己的力量进行了大胆的尝试，在原设计基础上对制浆工艺、设备选型、生产控制进行相应的完善和创新。     

水煤浆的燃用及其环境影响

自爆发石油危机以来,寻求取代石油作燃料的研究曾盛极一时,除了刺激核电发展外,对煤碳的一发利用又被重视起来。在模拟液体燃料方面水煤浆独具一格,具有燃油的某些特点,是煤的加工产品中较为理想     

湿法脱硫系统槽内衬的选择

湿法脱硫系统中浆槽接触的浆液具有腐蚀和磨损性，浆槽内部应合理选择内村加以保护。本文介绍了美国湿法脱硫系统浆糟的常用内初材料与内衬方法以及技术经济评估．     

Temporal Trends in Mercury Accumulation in Lake Sediments in Sweden

Lake sediment cores were analyzedto study the history of mercury (Hg) pollution andparticularly to determine whether recent sedimentconcentrations have declined in response todeclining atmospheric deposition of Hg. Sedimentcores from 6 forest lakes distributed fromsouthern to northern Sweden and 3 northernmountain lakes were analyzed for Hg using CVAAS. A400 cm sediment profile from Måkevatten insouthwest Sweden indicates that the onset of Hgpollution occurred in the 18th century. Anindisputable increase in Hg concentrationsoccurred concurrent with the appearance ofspheroidal carbonaceous flyash particles (SCP)derived from fossil-fuel combustion, in themid-19th century. There is a strong correlationbetween Hg and SCP concentrations in the sedimentcores (r=0.67 to 0.91), which suggests a strongrelationship between historical Hg pollution andfossil fuel burning. In contrast to sediment corestaken in 1979, maximum Hg concentrations are nowobserved below the sediment surface and declinetowards the sediment surface. This study confirmsthat reductions in atmospheric deposition of Hgover Sweden have resulted in a decreased transferof total Hg to aquatic environments as reflectedby lake sediments, and that lake sediment profilesof Hg concentrations reflect relative trends inthe atmospheric deposition of Hg rather thanpost-depositional diagenetic processes.     

Elemental Concentration in Lichen in Western Anatolia

The deposition patterns of Mn, Fe, Cr, Sb, Zn and As wereinterpreted together with enrichment factor calculations. Samples collected around iron-steel plant had very high concentrations and EF values of Mn, Fe, Cr, Sb and Zn implying that these plants are serious pollution sources in the region. High As concentrations around the settlementareas showed that coal combustion is another important anthropogenic source in the region.     

Volumetric changes in landfill gas flux in response to variations in atmospheric pressure

This paper develops a quantitative model which attempts to relate volumetric changes in landfill gas emissions to variations in the surface atmospheric pressure. The model considers gas emissions as the sum of two terms, one constant over a period of weeks, and the other able to vary on a scale of hours. Results from computer simulations are given which indicate that the magnitude of the variable factor is proportional to the rate at which surface pressure is changing, rather than the actual value of the surface pressure.     

Sulphate and Nitrate in Precipitation and Soil Water in Pine Forests in Latvia

The SO₄–S and NO₃–N concentrations and pH in bulk precipitation, throughfall, stemflow and soil water for the 1994–2004 period were studied in pine forests in Latvia (Rucava and Taurene Integrated Monitoring stations). The SO₄–S and NO₃–N concentrations decreased over the study period, simultaneously with a decrease of acidity in precipitation. The changes were more evident in the western part of Latvia, probably due to declining long-range air pollution from West Europe. The trend of decreasing sulphate concentrations and increasing pH in precipitation were not followed by respective changes in soil water. In the upper soil horizon sulphate ion concentrations and acidity increased in soil water. Over the observation period, nitrate concentrations also showed an increasing trend in soil water at Rucava and Taurene, but these changes were not statistically significant.     

Variations in the Fluoride Level in Precipitation in a Region of Human Impact

The research concerns the Wielkopolski National Park (West Poland), which suffered a huge human impact in the 1970s and 1980s owing to the nearby location of an industrial plant. Since then, fundamental technological changes that it introduced into its production of phosphate fertilizers have radically reduced the amount of pollution emitted. A three-year study (2002–2004) of fluorides in precipitation in open terrain and under tree crowns showed their concentrations to range from levels below the detection limit (0.003 mg/l) to 0.560 mg/l. Those registered under tree crowns were several times higher and indicated substantial dry deposition of fluorides on the trees. The highest values were recorded in 2003, with 43% of samples ranging from 0.01 to 0.05 mg/l, and with 51% of throughfall ranging from 0.10 to 0.50 mg/l. A strong connection was shown to exist between fluoride and sulphate concentrations in the precipitation. An analysis was made of the available data on F concentrations in the air and the dust levels around the factory, but these figures did not show an unequivocal effect on F concentrations in precipitation. A great similarity was found to occur between the fluoride content in rainwater in the Wielkopolski National Park and in the centre of the nearby Poznań metropolitan area, which indicates that there are also other F sources besides the local factory.     

Difficulties in applying extended producer responsibility policies in developing countries: case studies in e-waste recycling in China and Thailand

Developing Asian countries have started to apply the principle of extended producer responsibility (EPR) to electronics and electrical equipment waste (e-waste). This policy approach aims to give electronic appliance manufacturers and importers responsibility for the collection and recycling of discarded electronic equipment. China and Thailand have drafted regulations on the recycling of e-waste with common characteristics such as the financial responsibility of producers and subsidies for collection. Although the proposed system is sensible, taking into account the fact that e-waste is a market-traded commodity, there are two major difficulties in implementing EPR in developing countries. First, it may be difficult for governments to collect funds from producers or importers if smuggled, imitation, or small shop-assembled products have a large share in the market. Second, the system creates incentives for collectors and recyclers to over-report the amount of collected e-waste in order to gain extra subsidies from the fund. Other policy measures such as the enforcement of pollution control regulations on informal recyclers, the prevention of smuggling, and the protection of intellectual property rights should accompany EPR policies.     

Medical wastes characterisation in healthcare institutions in Mauritius

This study was initiated to characterize solid and liquid wastes generated in healthcare institutions and to provide a framework for the safe management of these wastes. The project was carried at three major medical institutions, namely, the Jeetoo Hospital, the Sir Seewoosagur Ramgoolam National (SSRN) Hospital and the Clinic Mauricienne. A waste audit carried out at these sites revealed that approximately 10% of solid wastes was hazardous in nature, consisting mainly of infectious, pathological and chemical wastes. The average amount of hazardous wastes per patient per day was found to be 0.072 kg at Jeetoo hospital, 0.091 kg at SSRN hospital and 0.179 kg at the clinic. The amount of hazardous wastes generated as a function of the number of occupied beds was found to follow a relationship of type y=0.0006x-0.19, where y was the amount of hazardous wastes generated per bed per day and x was the number of occupied beds. The waste quantifying process also revealed that at SSRN Hospital, 0.654 m(3) of water was being consumed per patient per day and the amount of wastewater produced was 500 m(3)/day. Further analysis revealed that the wastewater was polluting with chemical oxygen demand (COD), biological oxygen demand (BOD(5)), total suspended solids (TSS) and coliform content well above permissible limits.     

Future trends in computer waste generation in India

The objective of this paper is to estimate the future projection of computer waste in India and to subsequently analyze their flow at the end of their useful phase. For this purpose, the study utilizes the logistic model-based approach proposed by Yang and Williams to forecast future trends in computer waste. The model estimates future projection of computer penetration rate utilizing their first lifespan distribution and historical sales data. A bounding analysis on the future carrying capacity was simulated using the three parameter logistic curve. The observed obsolete generation quantities from the extrapolated penetration rates are then used to model the disposal phase. The results of the bounding analysis indicate that in the year 2020, around 41–152 million units of computers will become obsolete. The obsolete computer generation quantities are then used to estimate the End-of-Life outflows by utilizing a time-series multiple lifespan model. Even a conservative estimate of the future recycling capacity of PCs will reach upwards of 30 million units during 2025. Apparently, more than 150 million units could be potentially recycled in the upper bound case. However, considering significant future investment in the e-waste recycling sector from all stakeholders in India, we propose a logistic growth in the recycling rate and estimate the requirement of recycling capacity between 60 and 400 million units for the lower and upper bound case during 2025. Finally, we compare the future obsolete PC generation amount of the US and India.     

Material reuse and recycling in construction works in Japan

Journal of Material Cycles and Waste Management - The status of material reuse and recycling in Japan is reviewed with an emphasis on the efforts by the national government. First, the national...     

Field Intercomparison of Main Components in Air in EMEP

Within the European monitoring network (EMEP, ) several different sampling procedures for measuring the main air components have been applied. This has contributed to systematic concentration differences and a comparability problem. Since 1997 co-located experiments in 15 countries have been carried out to quantify these differences. In addition, three major measurement campaigns were organized by EMEP between 1985 and 1991. Differences among results depend on the concentration level and methods used. The decrease in SO₂ concentrations over the last twenty years has placed greater demands on the methodology. Absorbing solutions methods for SO₂, (H₂O₂ and tetrachloromercurate (TCM)) typically have higher detection limits than the reference method, which uses KOH impregnated filters. The TCM method also has problems with negative interference, especially in summertime. UV fluorescence monitors have in a few cases proven to give good results, but interferences, detection limit and poor maintenance can be problems. For NO₂, many countries are using the TGS absorption solution method, which has a higher detection limit than the reference method using NaI impregnated glass sinters. The Salzmann method gives unreliable results at concentrations below 1 μgN/m³, and even at higher concentrations the uncertainty is rather unsatisfactory. The chemiluminescence monitor with molybdenum converters tends to systematically overestimate NO₂ concentrations, possibly because zero-drift problems and the non-specific response to NO₂. Particulate sulphate measurements in general have lower bias and uncertainties than gas and other aerosol measurements.