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111.
为了解决皮带输煤暗道运输过程中粉尘污染严重及冬季供暖不足问题,对暗道通风供热系统进行了优化改造研究。以中煤平朔安家岭264输煤暗道为例,基于气固两相流理论,利用CFD模拟方法,对暗道内由风速对悬浮粉尘浓度分布的影响规律进行数值仿真。模拟结果显示:当输煤暗道排尘风速由0.25 m/s升至0.35 m/s时,粉尘浓度降为3.2 mg/m3,暗道最大通风阻力为245.94 Pa,最低换热量747.68 kW。基于数值模拟结果,从3种优化方案中选定一压一抽联合式通风除尘方案进行改造,现场实测除尘效果良好,表明所提出的输煤暗道通风除尘方案具有实践指导意义。  相似文献   
112.
湿法脱硫石膏脱水系统设备配置及优化   总被引:1,自引:0,他引:1  
石膏脱水系统作为FGD的重要辅助系统,对于吸收塔运行指标、荣液条件、物料平衡、经济运行、副产物综合利用都有重要作用。介绍了湿法脱硫石膏一、二级脱水系统的流程和设备特点,着重分析研究了系统中一级脱水设备、皮带机冲洗系统、滤液水系统、废水旋流设备等的配置、选型和优化方案。  相似文献   
113.
Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental) on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island. M.W. Newcomer, deceased  相似文献   
114.
Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary known feeding area of the endangered western gray whale (Eschrichtius robustus) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution, abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective, the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess (a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related variable (seg3d, i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total) has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding area remained stable during the seismic survey. M. W. Newcomer, Deceased.  相似文献   
115.
以安徽沿江为实证,采用加权平均旅行时间指标,分析了高速公路网构建对节点区内联系及区外联系可达性格局的影响,并以此为基础,综合分析了节点总体可达性格局的变动;随后对总体可达性的变动幅度及其相对可达性变动格局进行了探讨。结果表明:安徽沿江高速公路网络的构建显著提高了区域整体可达性,且促进了可达性的均衡化;区内联系可达性、区外联系可达性及总体可达性三者格局特征不同,路网构建所形成的影响也各有差别;东部及北部地区可达性变动幅度小于西南部地区;根据可达性系数的变化幅度及方向,可将节点归为相对可达性下降、相对可达性稳定及相对可达性上升3类。  相似文献   
116.
马大和 《林业劳动安全》2007,20(2):38-39,21
火烧防火线在东北林区应用广泛,是预防森林火灾的重要措施.这项工作由于受天气、可燃物、点火技术等各方面因素影响较大,应用时具有一定的风险性.本文针对火烧防火线过程中,用火条件的选择、点火技术的运用以及用火安全等方面加以分析.  相似文献   
117.
This paper describes a method of estimating the “true” internal costs of industrial waste, aimed at promoting environmentally friendly waste management. The study employs contribution margin analysis and a model – The Model for Efficient Use of Resources for Optimal Production Economy (EUROPE) – introduced by the author for assigning industrial costs to waste. In a business sense, waste is regarded as having the same basic status as any normal industrial product – the equality principle. Application of the method is suggested to create incentives for environmental improvement and profitability improvement in companies. Although the results of two case studies show the generation of waste to have a substantial negative impact on the final operating income, due to the internal shadow price costs it creates, this is regarded as an unavoidable consequence of the companies' acting in accordance with the principle of sustainable development. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
118.
PROBLEM: In the United States, teenage drivers have a higher crash risk and lower observed seat belt use than other age groups. METHOD: Seat belt use was examined for teenage (16-19 years) drivers who were fatally injured in traffic crashes occurring in the United States during the years 1995-2000. Vehicle, driver, and crash factors potentially related to belt use were examined. State differences in belt use rates among fatally injured teenage drivers were related to states' observed belt use rates for all ages and other state-level variables. RESULTS: During 1995-2000, mean belt use was 36% among fatally injured teenage drivers and 23% among fatally injured teenage passengers. One of the strongest predictors of higher belt use for both drivers and passengers was whether the crash occurred in a state with a primary seat belt law. Belt use rates for 1995-2000 for fatally injured teenage drivers ranged from 20% or less in six states to more than 60% in two states. States with the highest use rates were those with strong primary belt use laws and those with high rates of observed belt use for all ages. Lower belt use among fatally injured teenage drivers was associated with increasing age; male drivers; drivers of SUVs, vans, or pickup trucks rather than cars; older vehicles; crashes occurring late at night; crashes occurring on rural roadways; single vehicle crashes; and drivers with BACs of 0.10 or higher. Teenage driver belt use declined as the number of teenage passengers increased, but increased in the presence of at least one passenger 30 years or older. IMPACT ON TRAFFIC SAFETY: It is suggested that to increase teenage belt use, states should enact strong primary belt use laws and mount highly publicized efforts to enforce these laws. Graduated driver licensing systems should incorporate strong provisions that require seat belt use by teenage drivers and passengers.  相似文献   
119.
On November 13-14, 2003, a symposium on high-visibility safety belt use enforcement in Raleigh, NC: (a) celebrated the 10th anniversary of North Carolina's Click It or Ticket program; (b) documented current knowledge regarding safety belt use; (c) proposed strategies to increase use further; and (d) discussed research to support these strategies.  相似文献   
120.
山脊防火林带有效结构的研究   总被引:4,自引:0,他引:4  
防火林带的防火性能与阻风性能密切相关。本实验采用风洞模拟方法,对通风结构、疏透结构和紧密结构3种防火林带附近的风速进行测定,绘制了3种结构防火林带迎风面的风廊线。结果表明:紧密结构与疏透结构防火林带附近的阻风性能比较好,而通风结构阻风性能最差;但紧密结构防火林带上方的相对风速高达130%,为飞火的产生创造了条件;疏透结构林带上方的最大相对风速只有110%,不具备飞火产生的条件。所以,山脊防火林带的有效结构为疏透结构。  相似文献   
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