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551.
随着我国医疗废物处理的各项法规、条例等规章制度的建立和健全,彻底实现医疗废物的无害化、减量化、资源化,对处理工艺及主要设备的合理选择提出了更高的要求。在此就中原某市医疗废物无害化处理工程设计工艺及热分解炉的选择特点做出了较明确的阐述,可供参考。 相似文献
552.
热水解预处理改善污泥的厌氧消化性能 总被引:35,自引:9,他引:26
先将污泥进行热水解预处理 ,其后测定生物化学甲烷势(BMP)来研究热水解对污泥厌氧消化性能的影响 .结果表明 ,热水解预处理能加速污泥中固体有机物的溶解 ,溶解后的有机物进一步水解生成低分子物质 ,其中挥发性有机酸占溶解性COD(SCOD)的30%~40% ,从而污泥的厌氧消化性能得到明显改善 .最合适的热水解温度和热水解时间为170℃、30min.此条件下 ,污泥厌氧消化时总COD(TCOD)去除率从预处理前的38.11%提高到56.78% ,污泥中TCOD的沼气产率从16.0mL/g提高到250mL/g . 相似文献
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对2004-2005年上报国家环境保护总局环境工程评估中心的437个火电项目环境影响和宏观对策分4种方案进行了分析和探讨.结果表明:方案Ⅰ和方案Ⅱ的能源弹性系数分别为3.6和2.2,对环境、资源影响较大,不利于可持续发展;方案Ⅲ能源弹性系数为0.5,对环境、资源影响小,符合可持续发展,但目前难以实现;方案Ⅳ能源弹性系数为0.8,对环境、资源影响较小,按方案Ⅳ模式发展也有一定难度,但经过艰苦努力可以实现.分析了火电发展对煤炭资源和环境等方面的影响,并提出应尽快将我国能源弹性系数恢复到正常值,统筹火电厂规划,坚持经济发展模式的转变、节能降耗、调整产业结构等建议. 相似文献
555.
ABSTRACT: A scaled hydraulic model was used as a schematic representation of the Peach Bottom Atomic Power Station (PBAPS) discharge into Conowingo Pond during critically low river flows. The model approximated flow and temperature patterns and the degree of recirculation are assessed. Under normal operation the effluent is carried downstream and dissipated within about two miles. However, during dry weather years, river inflows can decrease substantially, resulting in unknown recirculation of effluent and flow patterns in Conowingo Pond. This study was conducted to investigate and predict flow patterns in Conowingo Pond under critically dry weather conditions. A threshold river flow is also identified that indicates a measure of the river's ability to maintain downstream advection of the effluent. The study suggests a number of unexpected current patterns, potential recirculation of the effluent, and changes in the dilution of the effluent. 相似文献
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558.
Ivan Dolezal Kausik Bal 《International journal of occupational safety and ergonomics》2019,25(4):562-567
Measurement of thermal resistance of polymer sheets and fibrous layers is important in various applications including those within the engineering, ergonomics, clothing design and personal protective equipment fields. Standard methods for measurement of thermal resistance of plain materials are generally time consuming, expensive and often require the sample to be cut. Moreover, the temperature difference between the surfaces of both plates surrounding the sample must be known, as well as the sample thickness. This article describes a new measuring device named the Thermoscope. The Thermoscope is not limited by the aforementioned requirements and is able to evaluate the thermal resistance of polymer sheets and textiles by touching the sample on one surface alone. Simultaneously, the other surface is kept in thermal contact with the supporting base. The accuracy of this device was compared with the Alambeta thermal insulation tester. Effects of various base materials on measurement precision were also studied. 相似文献
559.
《International Journal of Sustainable Engineering》2013,6(2):128-134
Natural fibres are nowadays increasingly being employed for producing protective clothing and sportswear. Due to economic and/or environmental considerations they are replacing synthetic materials. The present work provides an insight into the design and development of a novel comfort liner for a motorcycle helmet. The liner is produced from wool and Tunisian alfa fibre. The plant of the alfa fibre is abundantly available in Tunisia. Furthermore, we describe a design concept for a liner that uses these natural fibres and phase change material to improve sweat absorption and perception of thermal comfort. The raw material, the processes involved and the solution to use the phase change material are analysed. The novel comfort liner can facilitate breathability and evaporative transfer of heat in the safety helmet. In addition, it increases comfort, well-being, and provides an indirect message to use natural fibres for textile support to preserve our environment. 相似文献
560.
Sirkka Rissanen Hannu Rintamäki Ingvar Holder 《International journal of occupational safety and ergonomics》2013,19(4):451-461
The suitability of the IREQ (insulation required) index for predicting the thermal responses of 6 participants wearing chemical protective clothing was tested during exercise at -20 and -25 °C. IREQ was used to calculate duration limited exposure (DLE). Measured DLE correlated (r= .899, p < .001) with the predicted DLE. In exposures exceeding 40 min, however, the predicted DLE tended to be 10-20 min too short compared to the measured one. During short exposures the prediction was 5-20 min too long. The results show that IREQ overestimated the cold strain in participants wearing chemical protective clothing during cold exposures longer than 40 min. Nevertheless, predicted DLE never exceeded measured times and thus the prediction was always safe from the occupational point of view. 相似文献