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201.
氨联产甲醇物料的危险性辨识、评价及安全措施 总被引:1,自引:5,他引:1
氨联产甲醇生产法是生产甲醇的一种主要方法。甲醇生产中的物料都是比较危险的化学品,该类化学品易燃、易爆,容易使人中毒,如果管理不善,一旦发生意外,将造成巨大经济损失和重大人员伤亡。笔者按照OHSMS(职业安全健康管理体系)标准,对氨联产甲醇生产系统中生产过程物料和成品物料的危险性进行辨识和评价,提出了在氨联产甲醇生产系统中有关生产运行的安全管理控制措施,为氨联产甲醇生产系统的安全生产提供了切实可行的手段和途径,旨在提醒人们对氨联产甲醇生产系统的安全生产引起充分重视。 相似文献
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203.
首先介绍了中国目前高土石坝建设现状,然后回顾了循环加荷动三轴测试技术、堆石料动力性质的研究、高土石坝动力反应分析方法和土石坝地震永久变形的研究进展,最后讨论了高土石坝抗震措施和土石坝地震安全评价及防灾对策专家系统的基本思路。 相似文献
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205.
Jin Zhang Qiang Yang Xiaofei Song Hui Qiao Junhao Zhang 《International Journal of Green Energy》2017,14(12):1011-1019
Electrospun cellulose acetate (CA) nanofibrous mats incorporated with capric acid was studied to fabricate form-stable phase change materials (PCMs) for storing/retrieving thermal energy. Electrospun CA nanofibrous mats with different porous structures and specific surface areas were firstly prepared through regulating the volume ratio of mixture solvent of acetone/dichloromethane (DCM). Effects of different volume ratio of mixture solvent and mat thickness on the morphological structure, specific surface area, and absorption capacity of CA nanofibrous mats were systematically investigated. The results indicated that CA nanofibrous mats were highly porous on the surface; hence, they were capable of absorbing a large amount of capric acid. The maximum absorption capacity of CA mats via electrospinning with volume ratio of acetone/DCM being 5/5 was ~95.8 wt%, due to its higher specific surface area of ~17.1 m2/g. The specific surface area and capric acid absorption capacity of CA nanofibrous mats increased with the increases of mat thickness. As the thickness of nanofibrous mats increased from 10 to 85 μm, the corresponding specific surface area and capric acid absorption capacity of mats increased respectively from 7.2 to 29.0 m2/g and 92.1 to 98.5%. Morphological structures, as well as the properties of thermal energy storage and thermal insulation of the fabricated form-stable PCMs, were studied by scanning electron microscopy, differential scanning calorimetry, and measurement of freezing times, respectively. The results indicated that the resulting form-stable PCMs could well maintain their phase transition characteristics and demonstrated great thermal energy storage capability and temperature regulation ability. 相似文献
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本文采用全国统一方法,检测了广西柳州地区常用建材中~(226)Ra、~(232)Th、~(40)K的比活度.以煤灰砖最高,石灰石最低。比活度依次为煤灰砖>粘土砖≈土壤>水泥>灰砂砖>混凝土制品>石灰石.经估算,煤灰砖致居民的有效剂量当量较大,为3.98mSv·a~(-1);其它各种建材致居民的有效剂量当量在0.23—1.01mSv·a~(-1)之间,低于、等于或略高于本底. 相似文献
208.
废铸砂是铸造工业在金属制品的生产过程中次生出来的一种细颗粒固体废弃物。研究其作为一种资源进行合理再利用是当前处置废铸砂、保护生态环境的良好对策。本文对废铸砂的环境特征、物理性质及废铸砂作为建筑材料在多种建筑制品及工程中的资源化再利用进行了综述研究,涉及的再利用领域包括混凝土、热拌沥青混合料、低强度填料、水泥、路基、路堤、阻水帷幕(屏障)和衬垫。调查发现,次生于黑色金属(铁和钢)铸造生产线的废铸砂是一种无害固体废弃物,正确处置和科学利用,对环境不会产生二次污染,在以上建筑制品及工程中的应用能满足相关技术、性能要求,可以替代相关的材料进行资源化再利用。 相似文献
209.
Combining the use of photocatalysts with cementitious materials is an important development in the field of photocatalytic air pollution mitigation. This paper presents the results of a systematic study on assessing the effectiveness of pollutant degradation by concrete surface layers that incorporate a photocatalytic material – Titanium Dioxide. The photocatalytic activity of the concrete samples was determined by photocatalytic oxidation of nitric oxide (NO) in the laboratory. Recycled glass cullets, derived from crushed waste beverage bottles, were used to replace sand in preparing the concrete surface layers. Factors, which may affect the pollutant removal performance of the concrete layers including glass color, aggregate size and curing age, were investigated. The results show a significant enhancement of the photocatalytic activity due to the use of glass cullets as aggregates in the concrete layers. The samples fabricated with clear glass cullets exhibited threefold NO removal efficiency compared to the samples fabricated with river sand. The light transmittance property of glass was postulated to account for the efficiency improvement, which was confirmed by a separate simulation study. But the influence of the size of glass cullets was not evident. In addition, the photocatalytic activity of concrete surface layers decreased with curing age, showing a loss of 20% photocatalytic activity after 56-day curing. 相似文献
210.
Many secondary materials are being considered for use as substitutes for natural aggregates in highway applications due to their suitable engineering and economic properties. During the design life of the application, recycled materials are exposed to freeze/thaw cycles and other aging processes such as carbonation, coupled with intermittent infiltration/wetting by precipitation events. In such scenarios, leaching of material constituents is a primary pathway for environmental impact. This paper presents results of the effect of freezing and thawing on the leaching behavior of major and minor constituents from a laboratory formulated granular cement-based material. Scenarios considered included water percolating through the material (flow-through) and run-off (flow-around), both important leaching pathways in highway environments. The effect of moisture content at the time of freezing, number of freeze/thaw (F/T) cycles, and material size reduction were investigated. F/T exposure and subsequent infiltration/wetting resulted in consolidation and self-cementing of the granular cement-based material. For the flow-around scenario, F/T exposure resulted in a reduction in constituent release with time and increasing F/T cycles. For the flow-through scenario, moisture content at the time of freezing was an important parameter and an increase in the release was initially observed due to preferential flow/cracks and/or constituent redistribution prior to a decrease that resulted from self-cementing during further thawing and percolation. 相似文献