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1.
Sławomir Stelmach Ryszard Wasielewski 《Journal of Material Cycles and Waste Management》2008,10(2):110-115
More than 1.1 million tons of municipal and industrial sewage sludge is produced annually in Poland. Most of this sewage sludge
is landfilled or used for recultivation and fertilization of soil. After accession of Poland to the EU, large investments
are planned for wastewater treatment, so it is expected that the amount of sewage sludge produced in Poland will grow in the
near future. It is well known that the combustion of sewage sludge is becoming a more and more popular utilization method
of such waste. Unfortunately, the current situation in Poland makes it impossible to incinerate the sewage sludge because
of a lack of incinerators. One possible solution for Poland is the co-firing of dried sewage sludge in existing coal-fired
utility boilers. This article presents results of initial Polish industrial trials of dried municipal sewage sludge and hard
coal co-combustion in an OP-230 pulverized coal boiler. Such a solution was shown to be technically viable and not to require
changes to the existing technological system. Cocombustion of sewage sludge with coal in power plants seems to be the best
solution for sludge utilization in the near future in Poland. 相似文献
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分析了燃煤电厂自动配煤功能难以实现的原因,介绍了手动配煤过程出现的诸多问题。结合秦皇岛电厂输煤程控系统的特点,对自动配煤系统的控制原则、参数设定以及操作实现进行了全方位的研究分析。 相似文献
3.
Wastewater remediation using coal ash 总被引:2,自引:0,他引:2
D. W. Kirk C. Q. Jia J. Yan A. L. Torrenueva 《Journal of Material Cycles and Waste Management》2003,5(1):0005-0008
Small-scale domestic septic tanks discharge excess nutrients such as phosphorus and nitrogen, as well as pathogens, which
can degrade local water supplies. Unfortunately, traditional chemical and physical treatments are not practicable for single-home
dwellings. This work reports on a potentially attractive solution to protect local water supplies by using a low-cost industrial
waste, coal ash, for contaminant removal. Coal ash is produced as a consequence of electric power generation. The majority
of the ash is disposed of in landfills and surface impoundments, or stored on- or off-site, producing large hills or leveling
valleys. Only a small portion of the ash is ever utilized, mainly by cement industries and road construction. For example,
in Canada less than 25% is used. Therefore, if useful applications can be found, an opportunity exists to make better use
of this waste material. Bench-scale laboratory experiments and full-scale field tests show that coal ash has the capacity
to remove phosphorus from domestic waste water. The experimental and field data demonstrate that phosphate levels and calcium
levels can be correlated, although not in a simple manner. In addition, the ash in packed beds removed total suspended solid
(TSS), biological oxygen demand (BOD), ammonia nitrogen (NH3—N), total Kjeldahl nitrogen (TKN), and E. coli. The removal of E. coli was close 100% in the cases studied.
Received: May 20, 2002 / Accepted: October 5, 2002 相似文献
4.
Refuse from passenger trains is becoming a significant issue with the development of the Chinese railway. Co-firing is regarded as a promising thermal technology, both environmentally and economically, in reducing the quantity of refuse. The co-firing property of passenger train refuse with coal, however, may differ due to the differences in the composition of the refuse. In the present study, combustion properties of refuse from passenger train samples and the mixture of refuse with coal were studied in a tube furnace. Thermo analysis methods, such as thermogravimetry (TG), differential scanning calorimetry (DSC), differential thermal analysis (DTA) and derivative thermogravimetry (DTG) analyses were employed to evaluate combustion performance. We found that the mixture of passenger train refuse and coal at a ratio of 1:1 has a lower ignition and burnout temperature than the coal-only sample. Moreover, refuse from railway passenger trains has more reactive combustion properties than the coal-only sample, and the addition of railway passenger train refuse to coal can promote the reactivity of coal. 相似文献
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Journal of Material Cycles and Waste Management - Zeolites NaA and NaX were synthesized from initial coal gangue (milled sample) and pretreated coal gangue (calcinated and acid immersed sample) by... 相似文献
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James C. Hower Uschi M. Graham Amy S. Wong J.David Robertson Bethel O. Haeberlin Gerald A. Thomas William H. Schram 《Waste management (New York, N.Y.)》1997,17(8):523-533
Two Kentucky power plants burning similar blends of high-sulfur western Kentucky and southern Indiana coal provide a unique opportunity to examine the variations in coal combustion by-products due to differences in the method of wet flue-gas desulfurization (FGD). One plant employed carbide lime-based scrubbing for two units and a dual-alkali process for the third unit. The second plant employed a Mississippian limestone from Kentucky for all four units. This study provides an example of optical and SEM petrographic techniques, supplemented by chemical analyses, applied to the study of, at least from the geologic perspective, non-traditional materials. The coal sources comprise a blend of high volatile C and B bituminous, high vitrinite (85–90%, mmf), high-sulfur (> 3%, dry) coals. The fly ash is dominated by glassy phases (70–80%) with about 5–10% spinel (predominately magnetite), 3–10% quartz, and 4–10% isotropic coke comprising the remaining portion of the ash. SEM observations indicate that the glassy particles exhibit a bimodal size distribution with sub-micron glass spheres and a population of larger (several 10s of microns) spheres. The bottom ash has higher proportions of spinels and mullite, with negligible carbon forms, compared to the fly ash from the same units. Fly ashes were observed to be lower in Fe and higher in Al, Si, and S compared to the bottom ashes. Carbide lime, a by-product of acetylene manufacture, soda ash, and limestone were the reagents used in the flue-gas desulfurization processes. The primary FGD by-product is a calcium sulfite slurry which is vacuum filtered and mixed with fly ash and, usually, lime, to form a stable product for disposal. The FGD by-products have some potential, as yet unrealized, for utilization. 相似文献
8.
燃煤锅炉低NOx燃烧器的类型及其发展 总被引:3,自引:3,他引:3
阐述了3种控制燃烧过程NOx的低氮燃烧技术——空气分级燃烧、燃料分级燃烧及烟气再循环技术,分别介绍了几家著名的锅炉公司所开发的具有代表性的低NOx燃烧器的原理、结构及发展趋势。 相似文献
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国外煤炭产业发展循环经济的历史经验与趋势 总被引:2,自引:0,他引:2
孟赤兵 《再生资源与循环经济》2008,1(12):41-44
在过去两个多世纪里,煤——这种黑色的财富见证了世界经济的发展、科技进步、政治风云和社会变迁。煤炭支撑了世界经济的发展,推动了发达国家工业化进程,也给人类带来了难以抹掉的记忆。当人类为自己的工业成就欢欣鼓舞之时,又不得不在污浊的空气中忍受煎熬。50多年前的“伦敦烟雾事件”虽已成久远的历史,但它对今天的世界,尤其对那些正在经历工业化、现代化进程的国家,仍具有强烈的警示意义,经济的发展不能以污染环境作为代价,要加快发展循环经济,否则类似的悲剧就会重演。 相似文献
11.
介绍了壳牌煤气化技术的工艺特点和发展现状,分析论述了分布式能源系统技术,将煤气化与分布式能源系统两种技术完美结合,是当今煤-电-化组合的优良模式. 相似文献
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Xingrun Wang Yiying Jin Zhiyu Wang Yongfeng Nie Qifei Huang Qi Wang 《Waste management (New York, N.Y.)》2009,29(4):1330-1335
In this study, dry sewage sludge (DSS) as the principal material was blended with coal ash (CA) to produce lightweight aggregate. The effects of different raw material compositions and sintering temperatures on the aggregate properties were then evaluated. In addition, an environmental assessment of the lightweight aggregate generated was conducted by analyzing the fixed rate of heavy metals in the aggregate, as well as their leaching behavior. The results indicated that using DSS enhanced the pyrolysis–volatilization reaction due to its high organic matter content, and decreased the bulk density and sintering temperature. However, the sintered products of un-amended DSS were porous and loose due to the formation of large pores during sintering. Adding CA improved the sintering temperature while effectively decreasing the pore size and increasing the compressive strength of the product. Furthermore, the sintering temperature and the proportion of CA were found to be the primary factors affecting the properties of the sintered products, and the addition of 18–25% of CA coupled with sintering at 1100 °C for 30 min produced the highest quality lightweight aggregates. In addition, heavy metals were fixed inside products generated under these conditions and the As, Pb, Cd, Cr, Ni, Cu, and Zn concentrations of the leachate were found to be within the limits of China’s regulatory requirements. 相似文献
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Ling Wang He Sun Zhihui Sun Enqing Ma 《Journal of Material Cycles and Waste Management》2016,18(4):763-770
China has ranked first in the coal fly ash emission in the world. The multipurpose use of the fly ash from power plant waste is always an important topic for the Chinese environmental protection, which has drawn the concern of the government, scientific research departments, manufacturing enterprises and industry experts. This paper introduces an experimental research on how to recycle fly ash effectively, a kind of new technology of making bricks by which fly ash content could be amounted to 50–80 %. The article introduces raw materials of fly ash brick, production process and key control points. It introduces how to change the technical parameters of the existing brick-making mechanical device, optimize the parameters combination and improve the device performance. High-content fly ash bricks are manufactured, which selects wet fly ash from power plants, adding aggregate with reasonable ratio and additives with reasonable dosage, and do the experimental research on manufactured products for properties, production technology and selection about technology parameters of production equipment. All indexes of strength grade, freezing-thawing resisting, and other standards of the studied bricks reached the national standards for building materials industry. 相似文献
14.
Chien-Song Chyang Yun-Long Han Li-Wei Wu Hou-Peng Wan Hom-Ti Lee Ying-Hsi Chang 《Waste management (New York, N.Y.)》2010,30(7):1334-1340
Pollutant emissions from co-firing of refuse derived fuel (RDF) and coal were investigated in a vortexing fluidized bed combustor (VFBC). RDF-5 was made of common municipal solid waste (MSW). CaCO3 was injected in the combustor to absorb HCl at 850 °C. The results show that NOx and HCl emissions increase with RDF-5 co-firing ratio. The NOx concentration in flue gas at the bottom of the combustor is higher than that at the top. However, the trend of HCl released is reverse compared with NOx emissions. It was found that the HCl concentration decreases with increasing the molar ratio of Ca/Cl. However, the effect of CaCO3 addition on HCl retention is not significant when the molar ratio of Ca/Cl is higher than 5. The chlorine content in fly ash increases obviously with the molar ratio of Ca/Cl. PCDD/Fs emissions decrease slightly with an addition of CaCO3. In this study incomplete combustion is regarded as the main cause for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) formation. 相似文献
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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。 相似文献
16.
在简要说明生物质与煤共燃意义的基础上,对低温热解生物质和煤共燃的污染性能和经济性能进行了研究和评价.认为低温热解生物质(锯屑、谷壳和花生壳)与煤共燃能够减排CO2、CH4等温室气体及NOX和SO2等大气污染物,减排重金属污染物和其它微量有毒有害元素;同时,二者共燃可以在运输成本、存储成本、电厂生物质处理费用、设备改造费用和节约煤炭等方面降低电厂的运营成本,但也可能在生物质低温热解产品加工上提高生产费用以及在因燃用热解生物质可能造成的积灰结渣上提高设备维护费用.可以预见,生物质与煤共燃的研究将是实现能源可持续发展的有效措施之一. 相似文献
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《Waste management & research》1990,8(6):429-449
The results of large-scale lysimeter tests in which two pulverized coal fly ashes (PCFA) have been exposed to natural weather conditions for up to seven years are presented and compared with those of laboratory leaching tests. Laboratory column leaching tests on PCFA show good reproducibility, and comparisons between lysimeter and laboratory leaching results are promising for several salt ions and trace elements in the leachate when expressed in terms of the leachate to solids ratio (L/S). A long-term disposal strategy which takes into account the largely insoluble nature of PCFA is suggested. 相似文献
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Lakes caused by coal mining processes are characterized by low pH, low nutrient status, and high concentrations of Fe(II) and sulfate due to the oxidation of pyrite in the surrounding mine tailings. Fe(III) produced during Fe(II) oxidation precipitates to the anoxic acidic sediment, where the microbial reduction of Fe(III) is the dominant electron-accepting process for the oxidation of organic matter, apparently mediated by acidophilic Acidiphilium species. Those bacteria can reduce a great variety of Fe(III)-(hydr)oxides and reduce Fe(III) and oxygen simultaneously which might be due to the small differences in the redox potentials under low pH conditions. Due to the absence of sulfide, Fe(II) formed in the upper 6 cm of the sediment diffuses to oxic zones in the water layer where itcan be reoxidized by Acidithiobacillus species. Thus, acidic conditions are stabilized by the cycling of iron which inhibits fermentative and sulfate-reducing activities. With increasing sediment depth, the amount of reactive iron decrease, the pH increases above 5, and fermentative and as yet unknown Fe(III)-reducing bacteria are also involved in the reduction of Fe(III). Sulfate is reduced apparently by the activity of spore-forming sulfate reducers including new species of Desulfosporosinus that have their pH optimum similar to in situconditions and are not capable of growth at pH 7. However, generation of alkalinity via sulfate reduction is reduced by the anaerobic reoxidation of sulfide back to sulfate. Thus, the microbial cycling of iron at the oxic-anoxic interface and the anaerobic cycling of sulfur maintains environmental conditions appropriate for acidophilic Fe(III)-reducing and acid-tolerant sulfate-reducing microbial communities. 相似文献