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61.
本文通过对重熔用铝锭生产过程中铝的氧化烧损的原因分析,提出了在生产操作中添加熔剂进行渣铝分离和防止氧化烧损工艺技术以及铝渣冷却回收技术,达到减少铝的氧化烧损目的。 相似文献
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我国发展生物质发电技术的前景分析 总被引:10,自引:0,他引:10
介绍了发展生物质发电的必要性和客观必然性及其各方面优势条件,提出焚烧发电是生物发电发展的主流,给出了生物质发电的主要技术及其特点,阐述了生物质发电存在的问题和解决方法。 相似文献
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本文介绍了以低成本的拔头油(液态轻烃)替代液化石油气作为原料生产城市人工煤气的原理、技术方案及实施效果,分析了该项技术的市场应用前景,为科学利用炼油厂重整拔头油找到了一条理想的途径,对煤气生产企业降低成本、提高效益有一定帮助。 相似文献
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Particulate matter chemical component concentrations and sources in settings of household solid fuel use 下载免费PDF全文
Particulate matter (PM) air pollution derives from combustion and non‐combustion sources and consists of various chemical species that may differentially impact human health and climate. Previous reviews of PM chemical component concentrations and sources focus on high‐income urban settings, which likely differ from the low‐ and middle‐income settings where solid fuel (ie, coal, biomass) is commonly burned for cooking and heating. We aimed to summarize the concentrations of PM chemical components and their contributing sources in settings where solid fuel is burned. We searched the literature for studies that reported PM component concentrations from homes, personal exposures, and direct stove emissions under uncontrolled, real‐world conditions. We calculated weighted mean daily concentrations for select PM components and compared sources of PM determined by source apportionment. Our search criteria yielded 48 studies conducted in 12 countries. Weighted mean daily cooking area concentrations of elemental carbon, organic carbon, and benzo(a)pyrene were 18.8 μg m?3, 74.0 μg m?3, and 155 ng m?3, respectively. Solid fuel combustion explained 29%‐48% of principal component/factor analysis variance and 41%‐87% of PM mass determined by positive matrix factorization. Multiple indoor and outdoor sources impacted PM concentrations and composition in these settings, including solid fuel burning, mobile emissions, dust, and solid waste burning. 相似文献
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In the nuclear industry, safely managing spent fuels discharged from PWRs (pressurized water reactors) is an ongoing challenge. In this paper, a synergistic coupling of innovative small long‐cycle PWRs and advanced sodium‐cooled fast reactors is considered to reduce the accumulated TRUs (transuranics) by transmuting them with electricity production. In the coupling strategy, the innovative small PWRs employing UO2–ThO2 and fully ceramic micro‐encapsulated fuels are used to deeply burn TRUs from commercial PWRs, while advanced SFRs (sodium‐cooled fast reactors) with actinide recycling are designed to further transmute the TRUs discharged from innovative small PWRs. This work focuses on the core physics analysis of new SFR burner cores using different TRU feeds discharged from small PWRs. Additionally, quasi‐static reactivity balance analyses are performed to understand the safety of the SFR burner cores. The mass flows of TRUs in the nuclear park, which is composed of PWRs, small long‐cycle PWRs, and SFR burners, are analyzed to evaluate TRU inventory reduction. The results of this study show that the advanced SFR burners with all the TRU feed types discharged from the small long‐cycle PWRs have a high TRU consumption rate. They satisfy all of the conditions for self‐controllability under unprotected accidents with a reasonable number of control rods. This coupling strategy requires ~35% less power in conjunction with the advanced SFR burners in the nuclear park and increases the support ratio of SFR burners by ~42% than does the coupling of commercial PWRs and SFR burners. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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露天矿开采过程中边坡变形破裂过程一直是岩土工程领域研究的难点,尤其考虑含火烧煤层露天矿开采过程中的边坡稳定使得研究问题更加复杂。采用FEPG数值模拟的研究方法,对露天矿某边坡KT3剖面进行了破裂过程分析,得到了含火烧煤层露天矿边坡变形破裂规律,研究结果表明,边坡火烧砂岩的顶部首先出现拉张裂缝,边坡以压剪破坏为主,压剪破坏又促使拉张破坏,二者相互影响,最终导致边坡发生失稳破坏。 相似文献