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541.
矿井风流流经井下热水、干热岩、火灾地点等局部高温区域时,风流吸收热量使其内能增加,高温风流在巷道内流动时会产生热阻力。针对如何确定井下风流加热流动时巷道内热阻力的实测范围这一问题,通过理论推导与数值模拟的方法对巷道内热阻力分布情况进行分析。由压力场的模拟结果得出风流加热流动时,所产生的热阻力不仅存在于加热区,高温风流向加热区下风侧流动时热阻力仍然存在。模拟结果表明:对于水平等截面管道,风流流经加热区时,风流速压增加,加热区内风流的静压降幅大于全压降幅;流出加热区的风流向管道出口处流动时,高温风流不断克服阻力做功,并与管道内的新鲜风流、壁面进行热交换,风流温度逐渐下降,当测定区间为加热区入口至模拟管道出口时,风流的静压降幅与全压降幅近似相等。研究结果对井下巷道、隧道及实际工程应用中热阻力的分析与研究都具有重要价值。 相似文献
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生物质气化站在气化间与净化间之间设置防火墙后,会使气化反应余热无法向净化间内传递,使得我国北方地区气化站在冬季严寒情况下出现湿式净化装置冻裂,进而发生燃气泄漏的情况,增加了火灾、爆炸、中毒隐患。提出了一种利用风机套管将反应余热送入净化间采暖的技术,采用CFD(computational fluid dynamics)技术对采暖效果进行数值模拟,分析风机风量对采暖效果的影响,得出在风机风量对应进气口空气流速9 m/s时可获得最佳采暖效果,可使室外温度243.15 K时净化间内温度达到277~281 K。该技术利用余热进行采暖,达到了低碳环保、节能减排的目的。 相似文献
545.
随着我国电力事业的快速发展,电厂循环冷却水(温排水)的余热排放对受纳水体生态环境造成的负面热影响(即热污染)已日益引起社会关注。基于国内现有的温排水排放控制标准可执行性不强的现状,对我国电厂温排水的热污染控制标准的基础技术要素——温排水混合区边缘温升限值进行了研究。以我国北方某典型滨海核电厂址邻近海域的代表性海洋生物为研究对象,以各季节不同受试物种最大临界温度(CTM)的统计分析结果,作为确定该厂址温排水混合区边缘温升限值的主要依据。并结合法规调研法,最终确定该典型滨海核电厂址温排水混合区边缘温升限值的推荐值为3.6℃。 相似文献
546.
火电行业"十三五"主要大气污染物减排潜力情景分析研究 总被引:3,自引:0,他引:3
火电行业是总量减排的重点行业,也是主要大气污染物削减量的首要贡献者,其主要大气污染物排放量的削减抵消了其他行业的排放增长,为"十二五"全国减排任务的完成做出了重大贡献.本研究在火电行业主要大气污染物排放控制现状分析的基础上,结合火电行业技术政策措施要求,对火电行业"十三五"新增排放量进行了预测,并设置基于技术可行、排放标准以及超低排放三套减排情景,测算"十三五"减排潜力,评估火电行业"十三五"减排空间,对全国及各省火电行业减排形势提出了相应的意见和建议. 相似文献
547.
以武钢焦化公司6 m、7 m、7.63 m 3种炉型焦炉为对象,研究了焦炉加热过程中热力型氮氧化物的生成规律和影响因素。结果表明,焦炉氮氧化物排放量与炉型、空气过剩系数以及立火道温度有着直接的关系。7 m、7.63 m焦炉的氮氧化物排放量平均值均在210 ppm以下,6 m焦炉氮氧化物排放量平均值在400 ppm以上。6 m焦炉废气中NOx排放量明显高于7 m和7.63 m焦炉,这是由于7 m和7.63 m焦炉采用了分段加热方式,可以有效控制在焦炉加热过程中热力型NOx的生成,有利于减少最终烟气中NOx的浓度。 相似文献
548.
FENGQING LI YONG‐SU KWON MI‐JUNG BAE NAMIL CHUNG TAE‐SUNG KWON YOUNG‐SEUK PARK 《Conservation biology》2014,28(2):498-508
Globally, the East Asian monsoon region is one of the richest environments in terms of biodiversity. The region is undergoing rapid human development, yet its river ecosystems have not been well studied. Global warming represents a major challenge to the survival of species in this region and makes it necessary to assess and reduce the potential consequences of warming on species of conservation concern. We projected the effects of global warming on stream insect (Ephemeroptera, Odonata, Plecoptera, and Trichoptera [EOPT]) diversity and predicted the changes of geographical ranges for 121 species throughout South Korea. Plecoptera was the most sensitive (decrease of 71.4% in number of species from the 2000s through the 2080s) order, whereas Odonata benefited (increase of 66.7% in number of species from the 2000s through the 2080s) from the effects of global warming. The impact of global warming on stream insects was predicted to be minimal prior to the 2060s; however, by the 2080s, species extirpation of up to 20% in the highland areas and 2% in the lowland areas were predicted. The projected responses of stream insects under global warming indicated that species occupying specific habitats could undergo major reductions in habitat. Nevertheless, habitat of 33% of EOPT (including two‐thirds of Odonata and one‐third of Ephemeroptera, Plecoptera, and Trichoptera) was predicted to increase due to global warming. The community compositions predicted by generalized additive models varied over this century, and a large difference in community structure in the highland areas was predicted between the 2000s and the 2080s. However, stream insect communities, especially Odonata, Plecoptera, and Trichoptera, were predicted to become more homogenous under global warming. Impacto Potencial del Calentamiento Global sobre la Diversidad y la Distribución de Insectos de Arroyo en Corea del Sur 相似文献
549.
Socio-environmental conflict in the construction of a power plant in Spain's Basque Country: strategies,expertise and certifications 总被引:1,自引:0,他引:1
Gloria Baigorrotegui 《Local Environment》2015,20(1):114-129
Social and anthropological studies show a growing number of conflicts surrounding energy projects, as governments and companies insist on their implementation despite the concerns of local actors about their perceived socio-environmental risks. In this context, the purpose of this paper is to analyse the politicisation of expertise and certifications in a conflict over the construction of a combined cycle power plant by linking strategic assumptions from two particular sociological approaches. The first approach is based on the study of frame alignment in social movement organisations and the second on the translating interests in actor–network theory. These linked premises are examined in the conflict arising from the construction of a combined cycle natural gas plant in Boroa, in the Basque Country of Spain. This case study brings to light interesting findings on the strategies of the different agencies, certifications, politicisation of expertise and the increasing hostility in local conflicts. 相似文献
550.
AARON S. RUESCH CHRISTIAN E. TORGERSEN JOSHUA J. LAWLER JULIAN D. OLDEN ERIN E. PETERSON CAROL J. VOLK DAVID J. LAWRENCE 《Conservation biology》2012,26(5):873-882
Abstract: Climate change will likely have profound effects on cold‐water species of freshwater fishes. As temperatures rise, cold‐water fish distributions may shift and contract in response. Predicting the effects of projected stream warming in stream networks is complicated by the generally poor correlation between water temperature and air temperature. Spatial dependencies in stream networks are complex because the geography of stream processes is governed by dimensions of flow direction and network structure. Therefore, forecasting climate‐driven range shifts of stream biota has lagged behind similar terrestrial modeling efforts. We predicted climate‐induced changes in summer thermal habitat for 3 cold‐water fish species—juvenile Chinook salmon, rainbow trout, and bull trout (Oncorhynchus tshawytscha, O. mykiss, and Salvelinus confluentus, respectively)—in the John Day River basin, northwestern United States. We used a spatially explicit statistical model designed to predict water temperature in stream networks on the basis of flow and spatial connectivity. The spatial distribution of stream temperature extremes during summers from 1993 through 2009 was largely governed by solar radiation and interannual extremes of air temperature. For a moderate climate change scenario, estimated declines by 2100 in the volume of habitat for Chinook salmon, rainbow trout, and bull trout were 69–95%, 51–87%, and 86–100%, respectively. Although some restoration strategies may be able to offset these projected effects, such forecasts point to how and where restoration and management efforts might focus. 相似文献