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691.
高含硫天然气净化厂需对H2S含量较高的原料气进行处理,溶液循环量大、工艺流程长、公用工程消耗量大、能耗高。通过对天然气净化厂脱硫单元的耗能点及耗能关联因素进行分析,从优化工艺方案、采用先进节能设备、回收可回收的能量、减少工艺过程能量损失等方面,提出了热泵、贫液与半贫液分流工艺及板式换热器在MDEA脱硫单元中的应用及改造措施,详细阐述了各种节能措施的优势及适用条件。充分挖掘天然气净化厂的节能潜力,能够创造良好的经济效益和环境效益。  相似文献   
692.
岩体稳定性预报是微震监测工作的重要组成部分。探讨微震活动性参数变化作为岩体稳定性预测的可行性,结合用沙坝矿实际生产过程中观测到的现象,提出微震监测岩体失稳预报的一般模式。根据b值在岩体失稳前先增大后减小的趋势作为危险预警初始条件;并将能量指数、施密特数急剧下降以及累积视体积增加的时间段作为岩体失稳的预警期,将事件数的急剧下降作为危险的临界状态。用沙坝矿根据这一原理建立的岩体失稳预报模式可以达到采场失稳的智能预报,解决了人工判别预警期过程中效率低的难题,保障矿山的生产工作。  相似文献   
693.
我国可持续能源系统发展的途径探讨   总被引:4,自引:0,他引:4  
本文从大规模发展风能所要解决的问题入手,通过借鉴石油和天然气的经验,提出了以租赁方式发展风能的设想,并对我国利用租赁方式发展风能所要解决的问题进行了讨论。  相似文献   
694.
Objective: Fractures are a common injury among motorcycle riders and can have serious health implications. Impact protection (IP) has been designed to help prevent fractures, yet there are conflicting opinions as to whether this IP does in fact help prevent fractures in real-world crashes. This work aimed to (1) use simulated dummy impacts to examine whether existing types of IP could reduce the force transferred to the underlying bone to below fracture tolerance levels and (2) investigate whether current European Standard (EN 1621-1) test procedures for impact protectors designed for motorcyclists are sufficient to ensure fracture protection.

Method: Twenty-three shoulder and 7 knee IP specimens were tested using a 23-kg impactor contacting axially along the clavicle and femur of an anthropomorphic test device (ATD) at an energy level corresponding to the fracture tolerance of these bones. Sixteen IP specimens were the same as those worn by motorcycle riders involved in crashes where injury outcome was known (knee: n?=?3; shoulder: n?=?13) and the IP had been previously tested to EN 1621-1. Other IP tested represented a wide range of IP available for purchase at a motorcycle accessory store. Double and triple layers of IP were also tested. Energy attenuated during the dummy impacts was compared to energy attenuated when tested to EN 1621-1.

Results: Of the 23 shoulder IP tested, the average percentage reduction of transferred force to the shoulder from the baseline test was 7.6?±?4.8%. The percentage reduction of transferred force to the knee from the baseline was 43.9?±?7.5%. The entire group of knee IP tested reduced the transferred force to the knee to below the 10-kN injury threshold for the femur. There was a positive but nonsignificant correlation between the ATD test and the EN 1621-1 impact test performance, suggesting that the European standard test method likely provides a good indication of IP performance. However, given the low correlation coefficient, the relationship between IP performance in the European standard test method and injury protection remains unclear.

Conclusion: Though the energy attenuation test method in the European standard may be an appropriate approach, distinct differences in injury protection performance observed between knee and shoulder IP indicate that there may be a need for different performance criteria for IP designated to protect different body regions.  相似文献   
695.
将2001—2010年的主要能源材料消耗、主要污染物变化及主要行业分布进行了相关性分析,结果表明:兰州市大气4种主要污染物中除烟尘呈下降趋势外,废气总量、SO2、NOx仍呈上升趋势;主要污染源为燃煤,主要污染行业为电力、蒸汽热水产供业;废气和SO2排放总量与燃煤和燃气呈强正相关,而NOx排放只与燃气呈强正相关。建议发挥兰州地域优势,加大以水电供应为主的能源结构调整,对改善当地空气质量有重要价值。  相似文献   
696.
污水生物处理单元能量平衡与分析方法研究与应用   总被引:5,自引:0,他引:5       下载免费PDF全文
在提出污染物内能概念的基础上,对污水生物处理工艺能量平衡和分析的原理与方法进行了探讨,建立了能量平衡研究的基本模型。据此对国内四座不同工艺的城市污水处理厂进行了生物处理单元的能量衡算,并采用两类指标对处理单元耗能状况进行了评价。应用能量平衡分析方法可进行处理工艺的设计遴选和建成后运转效果的评判,以及指导处理厂有针对性地采取节能降耗措施。  相似文献   
697.
The incessant demand and consumption of energy services among individuals’ is increasing throughout the world. Individuals’ electricity consumption in Northern Cyprus has risen considerably. However, the demand for electrical energy services on the island is heavily reliant on imported fossil fuels. Burning fossil fuels has adverse effects on its environment. Therefore, sustainable energy consumption is required and individuals are targeted for energy conservation to reduce electricity consumption. Against this background, using the Structural Equation Modeling approach, this research incorporates social‐psychological factors; personal norms, positive and negative emotions into the theory of planned behaviour (TPB) model to assess the relationships among the variables, explain their impact on consumers’ electricity conservation intentions and enhance the explanatory power of the model. Data was conveniently obtained from a quantitative sample of 400 electricity consumers. The results indicate that negative emotions have the strongest significant influence on intentions, but personal norms have the least effect on intentions to save electricity. Furthermore, the study revealed that our expanded TPB model can provide improved explanatory power more than the original TPB. Policy implications, limitations and future research are discussed.  相似文献   
698.
Daily global solar radiation on a horizontal surface and duration of sunshine hours have been determined experimentally for five meteorological stations in Saudi Arabia, namely, Abha, Al-Ahsa, Al-Jouf, Al-Qaisumah, and Wadi Al-Dawaser sites. Five-years of data covering 1998–2002 period have been used. Suitable Angstrom models have been developed for the global solar radiation estimation as a function of the sunshine duration for each respective sites. Daily averages of monthly solar PV power outputs have been determined using the Angstrom models developed. The effect of the PV cell temperature on the PV efficiency has been considered in calculating the PV power output. The annual average PV output energy has been discussed in all five sites for small loads. The minimum and maximum monthly average values of the daily global solar radiation are found to be 12.09 MJ/m2/d and 30.42 MJ/m2/d for Al-Qaisumah and Al-Jouf in the months of December June, respectively. Minimum monthly average sunshine hours of 5.89 hr were observed in Al-Qaisumah in December while a maximum of 12.92 hr in Al-Jouf in the month of June. Shortest range of sunshine hours of 7.33–10.12 hr was recorded at Abha station. Minimum monthly average Solar PV power of 1.59 MJ/m2/day was obtained at Al-Qaisumah in the month of December and a maximum of 3.39 MJ/m2/day at Al-Jouf in June. The annual PV energy output was found to be 276.04 kWh/m2, 257.36 kWh/m2, 256.75 kWh/m2, 245.44 kWh/m2, and 270.95 kWh/m2 at Abha, Al-Ahsa, Al-Jouf, Al-Qaisumah, and Wadi Al-Dawaser stations, respectively. It is found that the Abha site yields the highest solar PV energy among the five sites considered.  相似文献   
699.
随着污泥处理处置问题的日益严峻,基于清洁生产理念的污泥过程减量化技术已成为业界的研究热点。超声波以其"绿色、高效"在污泥过程减量化工艺中引起了广泛关注。探讨了超声波促进污泥过程减量化的机理和主要影响因素,概述了单独利用超声波及超声波与其他技术联用促进污泥过程减量化的研究现状,展望了低强度超声波在污泥过程减量化中的应用前景和研究方向。  相似文献   
700.
武祝民  于宏兵 《环境工程》2016,34(8):170-173
为了给危险废物处理处置企业开展清洁生产提供一些基础性引导,先对比分析了危险废物处理处置企业和常规企业开展清洁生产的异同,然后以采用水泥回转窑协同处置危险废物的R公司为例,从8个方面进行产排污和清洁生产潜力分析,并结合危险废物处理全过程开展物料平衡分析,提出可行的无/低费方案和中/高费方案共19项。研究结果表明,危险废物处理处置企业存在可观的清洁生产和节能减排潜力,通过开展清洁生产可有效从源头防治二次污染,实现节能减排。  相似文献   
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