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211.
本文总结了各种类型除尘器在使用当地含挥发份较高的长焰煤种过程中的除尘效率,及其性能特点,详细阐述了冲击式湿式除尘器在燃用高挥发份煤锅炉除尘中的应用效果。 相似文献
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润湿性是水处理滤料的一个十分重要的表面性质.以Washburn方程为原理,用动态渗透压力法研究了无烟煤、铝矾土陶瓷及磁铁矿滤料的亲油亲水润湿性.实验结果表明,方法的重现性较好,误差在10%以内.当滤料的粒径范围在0.6~0.9mm之间时.以该法测得无烟煤、铝矾土陶瓷及磁铁矿滤料的亲油亲水比(LHR)值依次为2.511、1.748和1.317,说明无烟煤滤料的亲油性最好,铝矾土陶瓷次之,而磁铁矿的亲油性最差.XPS和FTIR分析结果表明,无烟煤、铝矾土陶瓷及磁铁矿滤料润湿性差别主要归因于其表面化学结构的不同. 相似文献
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为研究三元锂离子电池在空运低压环境中的安全性,通过自主设计搭建的封闭式变压实验舱开展相关实验,对不同荷电状态(SOC)下的三元锂离子电池在不同压力环境(101,80,60,40 kPa)下的热失控特性进行研究,采集电池热失控过程中的温度以及实验舱内的压力变化,并对热失控后实验舱内的气体成分进行分析。结果表明:三元锂离子电池热稳定性随着SOC的升高而下降,常压下100%SOC的电池热失控温度可达650.8 ℃,初始环境压力越低,相同SOC的电池热失控最高温度越低。随着环境压力的降低,相同SOC的电池在热失控后会生成更多CO,且电解液占比升高。研究结果可为锂离子电池空运安全性研究提供理论依据。 相似文献
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为研究加氢站用高压储氢容器在火灾下的安全性能,采用计算流体力学(CFD)方法对45 MPa高压储氢瓶式容器火烧试验过程进行模拟研究,结合气瓶火烧试验,分析高压储氢容器火灾下的热响应过程,研究不同因素对储氢容器压力泄放装置动作时间的影响。结果表明:613 s以内试验压力与模拟数据的最大相对误差为3.9%,模型误差在可接受范围;不同充装介质对安全泄放装置动作时间影响不大;不同充装压力对容器内介质压升速率影响较大,充装水平较高时压力泄放装置更快动作,较低的充装压力下容器内介质温升较快;不同环境温度对介质温升影响较小。 相似文献
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Felipe Silva Lilyan Fulginiti Richard Perrin Karina Schoengold 《Journal of the American Water Resources Association》2019,55(5):1085-1101
The High Plains Aquifer (HPA) underlies parts of eight states and 208 counties in the central area of the United States (U.S.). This region produces more than 9% of U.S. crops sales and relies on the aquifer for irrigation. However, these withdrawals have diminished the stock of water in the aquifer. In this paper, we investigate the aggregate county‐level effect on the HPA of groundwater withdrawal for irrigation, of climate variables, and of energy price changes. We merge economic theory and hydrological characteristics to jointly estimate equations describing irrigation behavior and a generalized water balance equation for the HPA. Our simple water balance model predicts, at average values for irrigation and precipitation, an HPA‐wide average decrease in the groundwater table of 0.47 feet per year, compared to 0.48 feet per year observed on average across the HPA during this 1985–2005 period. The observed distribution and predicted change across counties is in the (?3.22, 1.59) and (?2.24, 0.60) feet per year range, respectively. The estimated impact of irrigation is to decrease the water table by an average of 1.24 feet per year, whereas rainfall recharges the level by an average of 0.76 feet per year. Relative to the past several decades, if groundwater use is unconstrained, groundwater depletion would increase 50% in a scenario where precipitation falls by 25% and the number of degree days above 36°C doubles. Editor’s note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series. 相似文献
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Blessing Masasi Saleh Taghvaeian Prasanna H. Gowda Jason Warren Gary Marek 《Journal of the American Water Resources Association》2019,55(4):976-993
Use of models to simulate crop production has become important in optimizing irrigation management in arid and semiarid regions. However, applicability and performance of these models differ across regions, due to differences in environmental and management factors. The AquaCrop model was used to simulate soil water content (SWC), evapotranspiration (ET), and yield for grain sorghum under different irrigation regimes and dryland conditions at two sites in Central and Southern High Plains. Prediction error (Pe), estimated as the difference between simulated and measured divided by measured, for SWC ranged from ?17% to 4% in fully irrigated, ?3% to ?10% in limited irrigated, and ?16% to 25% in dryland treatments. The Pe within ±4%, ?5%, and ?17% to 24% were attained for seasonal ET under fully irrigated, limited irrigated, and dryland conditions, respectively. Pe values for grain yield were within those previously reported and ranged from ?10% to 12%, ?12% to 7%, and 9% to 17% for fully irrigated, limited irrigated and dryland conditions, respectively. Overall performance of the AquaCrop model showed it could be used as an effective tool for evaluating the impacts of variable crop and irrigation managements on the production of grain sorghum in the study area. Finally, the application of the model in the study area revealed planting date has a significant impact on sorghum yield and irrigation requirements, but the impact of planting density was negligible. Editor's note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series. 相似文献
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