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81.
以河津腾晖煤业为研究对象,基于智能化工作面开采及安全生产的需要,设计了智能化降尘系统,对该系统智能化控制关键技术进行了分析,提出了降尘点优化布置方案。该智能化降尘系统能较好地适应智能化开采技术的要求,实现了与综采智能控制系统的联动控制,降尘效果理想,为智能化开采提供了安全保障。 相似文献
82.
为了降低煤层气井排采过程中的储层伤害,通过分析松河井田的资源开发条件及煤层气井排采数据,总结各排采阶段不合理排采控制引起的储层伤害特征,提出不同排采阶段合理的排采工艺对策。分析结果表明:松河井田煤层气资源丰度达到2.09×10^8m^3/km^2,煤层气资源开发条件较好;松河井田多煤层合层排采过程中,不合理排采控制工艺对煤层气井的产气量影响较大;排采初期以速敏伤害为主,排采中期以气锁和应力闭合伤害为主;修井作业及停抽期间,气锁效应及应力闭合对煤层造成伤害的可能性增大。合理的排采控制能够有效降低煤层气井的储层伤害,提高煤层气井产气量。 相似文献
83.
为保障8809工作面推进过空巷区域的安全生产,通过对过空巷区域时覆岩变形规律的分析,得出工作面与未支护的空巷间煤柱宽度为14m时,空巷围岩出现失稳。基于分析结果,确定J09-01和J09-02空巷采取锚网索+工字钢梁的支护技术,J09-03和J09-04空巷采用预充填技术,工作面顺利通过补强支护和充填空巷区域。 相似文献
84.
85.
以煤矿放顶煤安全开采问题为对象开展分析探究。结合具体工程实际,在分析综放工艺技术特征的基础上,对综采放顶煤安全开采需注意的问题与防范措施开展深入分析,希望能够为其他矿井综放开采的有效开展提供借鉴和帮助。 相似文献
86.
87.
Zhenling Liu 《Energy Sources, Part B: Economics, Planning, and Policy》2018,13(3):169-172
The most important characteristics and limitations of solar energy were reviewed in this study. The analysis of different aspects indicated that the most important global challenges of solar energy development were climatic challenges, technical constraints, and unwillingness to make investments. After describing current conditions and predicting the future of solar energy, this study analyzed the policies formulated by developed countries to develop this from of energy. Accordingly, China has gotten ahead of other countries in this industry due to the technological production of solar panels and governmental supports. Finally, the economic estimation of solar energy was presented by dealing with the economic barriers to this form of energy in developed countries. According to the significant growth in the reduction of solar energy electricity production cost, this source of energy can be used as a major source in the future. It was then recommended to use a hybrid of solar energy with other sources such as wind to reduce the costs. 相似文献
88.
《Advanced Powder Technology》2020,31(1):287-299
The parameters governing the crystallisation of paracetamol using various conventional techniques has been extensively studied, however the factors influencing the drug crystallisation using spray drying is not as well understood. The aim of this work was to investigate the crystallisation of an active pharmaceutical ingredient through evaporative crystallisation using a spray dryer to study the physicochemical properties of the drug and to use semi-empirical equations to gain insight into the morphology and particle size of the dried powder. Paracetamol solutions were spray dried at various inlet temperatures ranging from 60 °C to 120 °C and also from a series of inlet feed solvent compositions ranging from 50/50% v/v ethanol/water to 100% ethanol and solid-state characterisation was done. The size and morphology of the dried materials were altered with a change in spray drying parameters, with an increase in inlet temperature leading to an increase in particle Sauter mean diameter (from 3.0 to 4.4 µm) and a decrease in the particle size with an increase in ethanol concentration in the feed (from 4.6 to 4.4 µm) as a result of changes in particle density and atomised droplet size. The morphology of the dried particles consisted of agglomerates of individual crystallites bound together into larger semi-spherical agglomerates with a higher tendency for particles having crystalline ridges to form at higher ethanol concentrations of the feed. 相似文献
89.
大气田是指天然气探明地质储量超过300×10~8 m~3、天然气峰值年产量在10×10~8 m~3以上且具有一定稳产期的气田。其是中国天然气储产量快速增长和未来长期稳定发展的重要基础,也是保障我国供气安全的关键。通过对国内外260余个大气田开发实践的系统分析和典型气田的解剖模拟,综合研究了大气田科学开发的内涵、核心技术以及全生命周期指标体系。大气田科学开发的内涵包括:①提出以"识别水、控制水、治理水"为技术体系的天然气开发理念,即常规气田"控水开发"、非常规气田人工压裂"注水开发",根据气藏类型和气藏特征,确定合理的采气速度;②综合评价气田开发经济效益和社会效益,保障气田长期稳产;③根据气井生产特征和储层发育特征,选取适用的气田稳产方式;④依据对常规与非常规气藏不同开发阶段的精细描述、气藏开发特征和生产动态的监测,确定气田可采储量、气田水与人工注水开发规律、气田提高采收率技术对策、气田效益稳产期与发展战略。大气田科学开发的核心技术包括:规模优化技术、科学布井技术、均衡开采技术和深度挖潜技术。进而综合优选出产量、压降、采出程度、单位压降产量等多个参数作为评价大气田科学开发的关键指标,建立了高压、低渗透—致密、裂缝—孔隙型和页岩气等4类气藏的全生命周期指标体系。结论认为,该研究成果有助于指导不同类型大气田的科学开发,进一步促进我国天然气产业的快速发展。 相似文献
90.
《中国稀土学报(英文版)》2020,38(11):1190-1200
Herein, a new mechanism involving Lewis acid-oxygen vacancy interfacial synergistic catalysis for aniline N,N-diethylation with ethanol was proposed, and the SO42−/Ce0.84Zr0.16O2–WO3–ZrO2 catalyst (SCWZ) with both Lewis acid sites and oxygen vacancies was synthesized by the hydrothermal method, which shows better catalytic activity than the reported solid acidic catalysts. Besides, the SO42−/ZrO2 (SZ) and SO42−/WO3–ZrO2 (SWZ) catalysts were also prepared and compared with SCWZ to investigate the synergistic effect of each component. The SO42− and WO3 mainly generate Lewis acid by bonding with ZrO2, which is beneficial for the fracture of the N–H bond in aniline. The Ce0.84Zr0.16O2 solid solution mainly plays a vital role in generating the oxygen vacancies as the interface active species, which can participate in stripping –OH from ethanol, then the carbocation will also be released, which only needs 1.3805 kcal/mol energy, calculated by density functional theory (DFT), to be input. In comparison, the traditional reaction mechanism needs the Brønsted acidic sites to promote the protonation of ethanol, then dehydration and subsequent formation of carbocation followed, and 108.6846 kcal/mol energy needs to be input, which is far higher than that of the new mechanism. The apparent activation energy (Ea) over SCWZ was measured by experiment to be 34.09 kJ/mol, which is much lower than that of SWZ (47.10 kJ/mol) and SZ (54.37 kJ/mol), illustrating comparatively preferable kinetics for SCWZ than that of SWZ and SZ. Besides, the conversion of aniline and selectivity to N,N-diethylaniline over SCWZ reach almost 100% and 73%, respectively. The SCWZ can be renewed for 4 times without rapid deactivation, and the longevity of SCWZ is longer than that of SWZ and SZ, as the loaded SO42− and tetragonal ZrO2 are stabilized by Ce0.84Zr0.16O2 and WO3, respectively. 相似文献