基于危险源的水利工程施工全过程安全管理研究

水利工程的特殊性,决定了其在安全管理构建中更加注重全过程管理机制的构建,以及危险源下的精准安全管控。在传统安全管理模式之下,水利工程安全管理盲点多、效率低,不利于全过程安全管理的高效实施。文章立足水利工程的危险辨识,分析了水利工程危险源全过程安全管理中的问题,并在此基础之上,从强化危险源精准辨识、构建危险源动态管理机制、优化危险源评价工作、加快危险源信息库建设等方面,具体论述了危险源下水利工程全过程安全管理措施。     

Simulation Study on Hydrogen-Heating-Power Poly-Generation System based on Solar Driven Supercritical Water Biomass Gasification with Compressed Gas Products as an Energy Storage System

Supercritical water gasification driven by solar energy is a promising way for clean utilization of biomass with high moisture content, but direct discharge of liquid residual causes energy waste and decreases energy efficiency. To reduce energy waste, a poly-generation system for hydrogen-rich gas production coupling heat supply and power generation based on supercritical water gasification of biomass driven by concentrated solar energy was established in this paper, which also provided a novel energy storage method to overcome the shortcomings of solar discontinuity. Thermodynamic model of the system was proposed and life cycle assessment(LCA) of the system was conducted. Influence of different parameters(temperature of 600℃ to 800℃, outlet temperature of heat exchanger of 42℃ to 56℃, biomass slurry concentration of 5% to 6.5%) on the gasification performance, energy and exergy efficiency, energy distribution and global warming potential(GWP) was discussed. The results indicated that hydrogen yield increased as gasification temperature increased since free radical reaction was enhanced which gas production reaction was classified into. Molar fraction of hydrogen increased as gasification temperature increased and reached 65.6% at 750℃. Energy and exergy efficiency of the system reached 74.84% and 34.87% at 700℃ and 600℃ respectively and that of gas production was 18.15% at 650℃, which was the highest. Increasing reaction temperature and decreasing biomass slurry concentration were effective ways to decrease GWP. Optimal operating parameter was reaction temperature of 650℃, outlet temperature of heat exchanger of 50℃ and biomass concentration of 5%.     

松木颗粒热解与高温蒸汽气化半焦产率及形貌特征分析

以成型松木颗粒为原料，进行低温热解，研究了热解温度和升温速率对生成的松木半焦产率及官能团的影响。以试验得到的松木半焦进行蒸汽气化试验，对比分析了温度对半焦重整气化形貌特征、比表面积和平均孔径的影响。研究表明：随着热解温度升高，松木半焦脂肪族结构峰消失转化为烃等小分子物质及气化气，进而降低半焦产率。升温速率升高，半焦产率呈先下降后升高的趋势，在800℃升温速率为30K/min时半焦产率最低。不同温度热解和蒸汽气化对比试验表明，温度相对较低时（500℃）热解和蒸汽气化半焦孔隙结构相近，随着温度的升高，蒸汽气化半焦结构发生明显变化，900°C时出现了更小的孔道结构且比表面积增加明显。蒸汽引入使松木半焦和水蒸气发生热解反应的同时发生了脱氢反应，气化半焦形貌出现熔融和烧结现象。     

Experimental investigation on gasification characteristics of polycarbonate (PC) microplastics in supercritical water

In order to solve the problem of marine microplastics and realize the harmless resource utilization of plastics, the gasification experiments of polycarbonate (PC) microplastics were carried out in supercritical water and a novel seawater gasification of microplastic experiment was investigated. In this paper, the effects of different operating conditions (temperature, time, feedstock concentration, pressure) on gasification performance were discussed. The gasification kinetic of microplastics in supercritical water was calculated. The experimental results showed that the increase in gasification temperature and time enhanced the cracking reaction and free radical reaction of the microplastics to increase the gasification efficiency, while the reduction in feedstock concentration improved the gasification efficiency by increasing the gasification level of unit feedstock. The change in pressure had no significant effect on gasification due to the fact that the properties of the supercritical water were not significantly changed. It was found that the valuable results that all alkali metal salts in seawater promote hydrogen conversion, while in terms of carbon conversion, only KCl, CaCl₂, NaHCO₃ and seawater had a significant catalytic effect on the gasification. Seawater gasification of microplastics was a potential resource utilization method. Finally, it was considered that the PC plastic gasification conformed to the random nucleation and subsequent growth model (n = 3), and the reaction activation energy was 230.45 kJ/mol, which was smaller than that of traditional pyrolysis.     

多晶硅生产中残液搅拌罐密封结构的改造

在处理多晶硅生产中产生的残液时,残液搅拌罐填料密封出现泄漏,针对此问题提出了优化措施,达到了预期效果。     

水位骤降对下伏隧道堤防安全影响研究

建立了考虑水位骤降条件下的下伏隧道堤防模型,依托湘江某下伏隧道堤防工程,基于堤防边坡渗流原理,结合有限元应力计算,探讨了不同水位骤降速率下的浸润线情况,计算了堤防安全系数。研究结果表明:湘江水位骤降速率越快,浸润线变化范围越大,浸润线变化范围与水位降落速率成正比;湘江水位骤降速度在3 m/d^4 m/d,水位降到28.8 m时,堤岸失去稳定;水位骤降并非整个过程中堤岸均处于失稳状态,而是水位降至某高度后堤岸失稳,骤降速率增快对堤防安全系数有一定负面作用。研究结果对隧道下穿堤防建设具有一定指导意义。     

65号航空冷却液的泡沫倾向性研究

针对65号航空冷却液在过滤循环中出现泡沫较多的现象，对65号航空冷却液泡沫倾向性进行探究。按照石化行业标准《发动机冷却液泡沫倾向测定法（SH /T 0066-2002）》，利用冷却液泡沫倾向测定仪来评价65号航空冷却液泡沫倾向性，并进行水乙二醇溶液对照试验。结果表明，航空冷却液在低温和循环时间较长的情况下，其泡沫倾向性较大，而随着温度的升高和循环时间的缩短，泡沫倾向性有一定程度的改善；并且通过水乙二醇对照试验可知，冷却液的基础液泡沫倾向性较小。航空冷却液在过滤循环中出现的泡沫问题，是加入的添加剂所引起的。     

卡尔费休法测定液态氯乙烯中水含量的研究

采用卡尔费休法测定了液态氯乙烯单体中的水含量。试验确定了采样工具、样品的预处理方式及选用溶剂的最优方案,并进行了精密度与准确度的验证。结果表明卡尔费休法测定液态氯乙烯单体中的水含量准确、快速,可以用来准确、及时地指导生产。     

智能工作面电液控制装置水处理系统应用分析

为保证智能综放工作面电液控制装置运行稳定和支架等设备的安全运行,采用由过滤器组、软化水装置、储水箱、自动配比装置等组成的水处理系统;该系统对进水进行高精度过滤,并进行酸碱等离子成分处理,保证乳化液的纯净度,维护电液系统及设备运行安全。试验表明,工作面回采过程中未出现电液装置及设备故障,应用效果好。     

瓦斯抽采钻孔水射流协同修护技术研究与应用

瓦斯抽采钻孔普遍存在因变形、煤渣积聚及塌孔等导致钻孔堵塞和抽采效果差的问题。通过分析钻孔塌堵失稳机制,得出煤岩体性质、地质构造及多应力耦合条件是造成钻孔失稳的主要因素,进而推断相应堵孔段情形。利用高压水射流解堵作用,提出了水射流疏通-筛管护孔协同修护技术,并研制出轻型气动钻孔修复装备。应用结果表明,该协同修护技术能有效解决瓦斯抽采钻孔塌堵后无法有效抽采的技术难题,试验钻孔修护深度达到50 m,修护完成后单孔抽采瓦斯浓度和瓦斯纯流量比修复前提高0.57~3.67倍和0.99~5.15倍,抽采效果大幅改善,实现了塌堵钻孔的快速便捷修复进而确保了瓦斯流动通道的畅通。