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271.
脱硫产业的发展机遇和面临的挑战 总被引:1,自引:2,他引:1
国家有关燃煤SO2污染控制的一系列法规政策的出台,促使火电厂烟气脱硫市场迅猛发展,为脱硫产业发展提供了良好的机遇。同时指出:脱硫工程正常运行将是对各公司的全面考验。 相似文献
272.
氨法烟气脱硫技术综述 总被引:17,自引:0,他引:17
简述了多种氨法烟气脱硫的原理和技术特点。主要介绍了湿式氨法烟气脱硫技术,为烟气脱硫技术的选择提供参考。 相似文献
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为推广非金属复合管在油田集输油领域的应用,明确其在集输环境中的老化特性是关键问题。基于集输油现场的工程条件,针对长庆油田试用的4731B型钢丝缠绕增强复合管,以采出原油、采出水为实验介质,通过挂片实验、水压爆破实验,借助电镜扫描、拉伸测试对复合管内衬层老化行为、拉伸性能以及复合管极限承压与老化特性进行研究。结果表明:采出原油与采出水均可渗透扩散进入内衬层内部,还会发生局部深入渗透;采出原油、采出水的局部渗透速率分别可达3.4,10.6 mm/a;在某些工况下,内衬层表面产生裂纹;短时间(168 h)内的介质渗透甚至裂纹对其机械性能影响较小,而光氧老化影响显著;现场服役813 d后,复合管极限承压下降2.79%,表明复合管承压性能稳定。 相似文献
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Zihong Xia Jian Li Tingting Wu Caixia Chen Xiaoke Zhang 《Waste management (New York, N.Y.)》2014,34(9):1609-1618
A CFD scheme was presented for modeling municipal solid waste (MSW) combustion in a moving-grate incinerator, including the in-bed burning of solid wastes, the out-of-bed burnout of gaseous volatiles, and the selective non-catalytic reduction (SNCR) process between urea (CO(NH2)2) and NOx. The in-bed calculations provided 2-D profiles of the gas–solid temperatures and the gas species concentrations along the bed length, which were then used as inlet conditions for the out-of-bed computations. The over-bed simulations provided the profiles of incident radiation heat flux on the top of bed. A 3-dimensional benchmark simulation was conducted with a 750 t/day commercial incinerator using the present coupling scheme incorporating with a reduced SNCR reduction mechanism. Numerical tests were performed to investigate the effects of operating parameters such as injection position, injection speed and the normalized stoichiometric ratio (NSR) on the SNCR performance. The simulation results showed that the distributions of gas velocity, temperature and NOx concentration were highly non-uniform, which made the injection position one of the most sensitive operating parameters influencing the SNCR performance of moving grate incinerators. The simulation results also showed that multi-layer injections were needed to meet the EU2000 standard, and a NSR 1.5 was suggested as a compromise of a satisfactory NOx reduction and reasonable NH3 slip rates. This work provided useful guides to the design and operation of SNCR process in moving-grate incinerators. 相似文献
278.
Scale Effects on Spatially Varying Relationships Between Urban Landscape Patterns and Water Quality 总被引:2,自引:0,他引:2
Scientific interpretation of the relationships between urban landscape patterns and water quality is important for sustainable urban planning and watershed environmental protection. This study applied the ordinary least squares regression model and the geographically weighted regression model to examine the spatially varying relationships between 12 explanatory variables (including three topographical factors, four land use parameters, and five landscape metrics) and 15 water quality indicators in watersheds of Yundang Lake, Maluan Bay, and Xinglin Bay with varying levels of urbanization in Xiamen City, China. A local and global investigation was carried out at the watershed-level, with 50 and 200 m riparian buffer scales. This study found that topographical features and landscape metrics are the dominant factors of water quality, while land uses are too weak to be considered as a strong influential factor on water quality. Such statistical results may be related with the characteristics of land use compositions in our study area. Water quality variations in the 50 m buffer were dominated by topographical variables. The impact of landscape metrics on water quality gradually strengthen with expanding buffer zones. The strongest relationships are obtained in entire watersheds, rather than in 50 and 200 m buffer zones. Spatially varying relationships and effective buffer zones were verified in this study. Spatially varying relationships between explanatory variables and water quality parameters are more diversified and complex in less urbanized areas than in highly urbanized areas. This study hypothesizes that all these varying relationships may be attributed to the heterogeneity of landscape patterns in different urban regions. Adjustment of landscape patterns in an entire watershed should be the key measure to successfully improving urban lake water quality. 相似文献
279.
高层建筑竖井火灾中影响因素众多,并且各因素对高层楼梯井火灾中重要现象、关键数值等的影响大小不一,使得此类火灾中的实验或理论研究成本较高。通过建立全局敏感性分析平台,定量考察了高层楼梯井结构所涉及因素的影响大小,并能够方便地筛选掉对所考察量影响较小的因素,以降低实验或计算成本。使用数值模拟方法,通过CFD软件对包含阶梯几何框架的高层楼梯井结构火灾进行了共计60次工况计算。并且根据计算结果,使用全局参数敏感性分析方法,得出建筑尺寸、热释放速率、环境参数对高层楼梯井内烟气湍流特性及输运特性的敏感性排序。结果表明,火源热释放速率对各输出参数的影响均占38%以上。 相似文献
280.
乌东德水库为季调节水库,采用宽度平均的立面二维水温数学模型对水库水温结构进行预测,结果表明:乌东德水库水温结构呈季节性分层特征,电站运行对下游水温过程有一定程度的春季低温水和冬季高温水影响。如果采用单层取水方案,在2~8月的下泄水温低于坝址现状水温,最大降幅为2.0℃,下泄低温水将对坝下鱼类产卵繁殖产生不利影响。乌东德水电站拟采取分层取水的措施,对低温水较为敏感的鱼类产卵期3~6月采用叠梁门取水。相比于单层取水,叠梁门方案对低温水的改善效果较明显,下泄水温提高了0.8~1.1℃,能一定程度地减缓升温期水温延迟效应。 相似文献