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101.
102.
《International Journal of Hydrogen Energy》2020,45(15):8757-8773
The subsurface storage of hydrogen (H2) provides a potential solution for load-balancing of the intermittent electricity production from renewable energy sources. In such technical concept, surplus electricity is used to power electrolyzers that produce H2, which is then stored in subsurface formations to be used at times when renewable electricity is not available. Blending H2 with natural gas (NG) for injection into depleted gas/oil reservoirs, which are already used for NG storage, is considered a good option due to the lower initial capital cost and investment needed, and potential lower operating costs. In this study, the potential impact of storing a mixture of H2 and NG in an existing NG storage field was investigated. Relevant reservoir, caprock and cement samples from a NG storage formation in California were characterized with respect to their permeability, porosity, surface area, mineralogy and other structural characteristics, before and after undergoing 3-month incubation experiments with H2/NG gas mixtures at relevant temperature and pressure conditions. The results indicated relatively small changes in porosity and mineralogy due to incubation. However, the observed changes in permeability were more dramatic. In addition, polymeric materials, similar to those used in NG storage operations were also incubated, and their dimensions were measured before and after incubation. These measurements indicated swelling due to the exposure to H2. However, direct evidence of geochemical reactions involving H2 was not observed. 相似文献
103.
介绍了焦化厂半干法烟气脱硫脱硝除尘一体化技术在焦化厂中的应用,描述了半干法烟气脱硫、低温选择性催化还原法(SCR)脱硝+除尘一体化工艺流程,该工艺运行效果、运行参数、工艺技术的特点,运行中常见问题及解决方法和未来需要进一步思考和解决的问题等。实践证明,该工艺技术在焦化厂能够长期稳定运行,脱硫脱硝及除尘效果较好,烟气指标可达到环保要求。 相似文献
104.
《能源学会志》2020,93(2):766-773
Ash deposition and condensation of acid vapors under deep-cooling of exhaust gas in a 1000 MW ultra-supercritical power plant were investigated. X-ray diffraction, X-ray fluorescence and laser particle size analyzers were employed to characterize the components, elements and particle size distribution of deposits at different metal wall temperatures. The results show that the deposits formed at the metal wall temperatures of 40 °C–60 °C were much thicker than the deposits at 70 °C–90 °C from the perspectives of the morphology and thickness. Fluorides and chlorides were observed in deposits formed at the metal wall temperatures of 40 °C–60 °C. Thin deposits were composed of Al-Si oxides and simple sulfates when the metal wall temperatures were 70 °C–90 °C. The dew-point temperatures of water, HCl and HF vapors were around 40 °C, 60 °C, and 60 °C, respectively. Basic ferric, aluminum and calcium sulfates, which were acted as traps to absorb the condensate and fly ash. Hydration played an important role in the growth of deposits formed at the metal wall temperature of 40 °C–60 °C. 相似文献
105.
为了研究缓蚀剂组分及添加条件对发射药性的影响,设计并制备了一种含新型有机硅的缓蚀剂材料;采用烧蚀管法,对比石蜡+TiO2型缓蚀剂,研究了新型有机硅缓蚀剂的静态降烧蚀效果;采用密闭爆发器研究了不同缓蚀剂添加条件对高能硝胺发射药点火和燃烧性能的影响;采用14.5mm弹道枪和壁温测试装置,研究不同缓蚀剂添加条件对膛壁温度、内弹道性能和枪口烟雾的影响。结果表明,采用含新型有机硅的缓蚀剂,降烧蚀效果更为显著;随着缓蚀剂添加量的增加,压力峰值、弹丸初速也会产生小幅下降,但总体影响幅度较小;添加缓蚀剂后,射击过程膛壁峰值温度显著下降,下降幅度随着缓蚀剂添加量的增加而增加,在缓蚀剂质量分数为3%时,对身管壁温降低幅度可达17.1%,且产生的枪口烟雾量较少;在缓蚀剂质量分数为5%时,缓蚀剂添加过量,枪口产生较大烟雾。该缓蚀剂及添加条件有望应用于低烧蚀发射药配方中。 相似文献
106.
针对高温烟气中煤焦的气化行为,本文采用FactSage 6.1计算了煤焦在高温烟气下的高温反应特性,并利用热重分析仪分析了煤焦气化行为。通过沉降炉实验进一步研究了不同温度、气体配比、粒径条件下气体产物的动态析出特性,同时计算了评价指标α、β、LHV值。结果表明:随着温度的升高,气体产物H2和CO的含量增加,β、α、LHV值增大,CH4和CO2的含量下降。在温度为1200℃时,β、α值分别由CO2/CO比为10∶70时的10.80%、5.21%增加到CO2/CO比为50∶30时的24.71%、41.06%。同时,随着CO2/CO比值的增大,高温烟气对煤焦气化反应抑制减弱。通过对比反应温度和粒径对煤焦气化反应的影响,得出反应温度远大于粒径对煤焦气化反应的影响。通过实验验证了向高温烟气中喷吹煤焦制备高品质可燃气体方法的可行性。 相似文献
107.
108.
《能源学会志》2020,93(4):1341-1353
This study focused on the effects of pyrolysis temperature on the structural characteristics and combustion properties of low rank coal. The combustion performance of semi-coke at different temperatures was studied by using low-temperature pyrolysis technology and non-isothermal thermogravimetric analysis. The variation of functional groups and carbon structure was quantitatively analyzed. The results show that the temperature has a significant effect on the semi-coke structure and flammability. In the middle and low temperature pyrolysis stage, the removal of water, volatile matter and functional groups is mainly carried out, and the degree of condensation and graphitization of carbon atoms is not obvious. The semi-coke performance with a pyrolysis temperature of 1023K is close to that of anthracite. The pyrolysis process is accompanied by the destruction of carbonaceous and the formation of mesopores, which affects the combustion performance. As the temperature increases, the flammability of the semi-coke is lowered, and the chemical structure of the semi-coke is a major factor affecting the flammability. The method of Coast-Redfern integration was used to calculate the kinetic parameters of the semi-coke. As the pyrolysis temperature increases, the activation energy of the combustion reaction increases, which is consistent with the trend of combustion performance change. 相似文献
109.
110.