基于性能参数退化的某弹用O型橡胶密封圈贮存寿命评估

目的研究某弹用O型橡胶密封圈的性能参数退化规律,并准确预测其贮存寿命。方法设计4个不同温度下的恒定应力加速退化试验,记录每个温度下不同时间点的性能退化数据,根据退化参数利用高分子材料性能变化与退化时间关系式及阿伦尼乌斯(Arrhenius)方程,建立O型橡胶密封圈压缩永久变形率与贮存时间的老化动力学方程。结果对照当地各个季节的平均温度值,建立了寿命评估模型,并由此预测了该型密封圈在自然环境贮存条件下的失效寿命在8年左右。结论该寿命评估值比较接近实际测量值,精度良好,可为O型橡胶密封圈在自然贮存条件下的寿命评估提供有价值的参考依据。     

油气储运设施事故风险指数模糊逻辑评估方法

油气储运设施风险是其事故发生概率和事故后果的综合度量,而事故概率和后果的定量评估结果往往是具有不确定性的数据,以确定性风险评估准则为基础的传统风险矩阵法和风险值法显然难以评估油气储运设施风险。为此提出开展油气储运设施事故风险的模糊逻辑推理法,首先,对风险矩阵的概率语言等级和损失语言等级的边界进行定量划分;然后,建立油气储运设施风险矩阵模糊集和模糊逻辑推理规则;最后,通过风险模糊推理运算和模糊风险解模糊化以确定油气储运设施的风险水平。实例应用与分析表明,利用推荐方法可得到较为详尽的风险数据信息,不但风险指数更加清晰,而且其所属风险等级类别也更加明确,评估结果能更好地指导油气储运设施的风险管理。     

浅议加油站清罐作业的HSE管理

介绍了加油站清罐作业的常见流程,以及清罐作业前的各项准备工作,探讨了加油站清罐作业过程的HSE管理措施及注意事项。     

某灵巧弹药红外敏感器部件贮存加速寿命试验应力的研究

对于结构复杂的新型弹药元件,难以通过传统的统计试验方法来验证其可靠性,而现阶段基于模型的加速寿命试验方法受到加速模型的限制,只适应于元器件级及材料级的传统弹药元件。在明确某灵巧弹药红外敏感器部件结构特征的基础上,以步进加速寿命试验理论与方法为依据,逐一对各组件进行分层次的贮存失效分析,归纳出贮存环境中导致红外敏感器部件失效的主要应力类型,并提出该部件可采取恒定湿度、步进温度的加速寿命试验方法进行可靠性验证。     

基于氢气充放试验及数值模拟的储氢气瓶安全评价

储氢气瓶是新能源汽车的重要储能设备,其可靠性直接关系到汽车的安全性。研究了不同环境温度下,35 MPa铝合金内胆车用储氢III型气瓶在充放气时的最终温度和应力分布情况,并对其安全性进行了评价。借助试验测试平台,在不同温度下进行了实际充放试验。试验过程中无漏气现象,且最终温度符合要求,表明储氢气瓶在试验条件下是安全的。由此,在获得了储氢气瓶充放时热响应规律的基础上,对不同温度下的氢气充放过程进行了数值模拟,得到其应力分布情况。结果表明,储氢气瓶复合层的应力远小于其材料抗拉强度,即内胆和复合层的强度均可视为满足要求。研究结果可为储氢气瓶的试验开展、安全评价、寿命预测提供依据。     

氯乙烯储罐注水堵漏腐蚀风险的预测方法研究*

为更好地解决氯乙烯储罐注水堵漏可能导致储罐发生腐蚀泄漏的实际问题,提出1种基于ASPEN和神经网络的氯乙烯储罐注水堵漏腐蚀风险的预测方法。运用ASPEN流程模拟软件,对氯乙烯储罐注水堵漏工艺进行模拟,得到不同泄漏孔径下注水速率和HCl浓度的关系;以HCl浓度作为导致腐蚀的主要影响因素,对不同种钢材进行挂片腐蚀实验;结合神经网络分析,得出HCl浓度与腐蚀速率之间的拟合式,预测储罐腐蚀情况。结果表明:神经网络预测结果平均相对误差7.63%,随注水速率的提高,HCl浓度变化呈下降趋势,腐蚀速率变化呈下降趋势;在等效泄漏孔径24 mm、注水速率0.87 m/s时,Q345R腐蚀速率13.93 mm/a,20#腐蚀速率10.48 mm/a,201不锈钢腐蚀速率7.09 mm/a为3者中最低,但此工况下,201不锈钢有点蚀倾向,储罐易发生穿孔,故201不锈钢不宜用作氯乙烯储罐母材,并提出对《石油化工企业设计防火标准(2018年版)》的修订建议。     

机场货站易爆危险品存储区外部安全防护距离研究*

为合理设定机场货站易爆危险品存储区外部安全防护距离,基于爆炸威力计算模型,利用有限元分析软件AUTODYN模拟包装约束下爆炸品爆炸冲击波特性,通过引入包装约束系数,描述包装材料对爆炸威力影响,计算航空运输易爆危险品存储区外部安全防护距离。结果表明:1 mm厚度聚碳酸酯、钢和铝材质外包装的包装约束系数分别为0.904 7,0.860 1,0.870 6,相较于聚碳酸酯和铝材质,钢材质外包装对易爆危险品爆炸威力削弱程度较大。研究结果可为机场货站外部安全防护距离规划设置提供参考。     

Decomposition of forest products buried in landfills

The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5 yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C + H) loss of up to 38%, while loss for the other wood types was 0–10% in most samples. The C + H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27 g OC g^?1 dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than previously reported.     

Characterization of municipal solid waste temporary storage sites: Risks posed to surrounding areas as a consequence of fire incidents

In this study temporary storage sites of municipal solid waste were characterized based on their potential social, health and environmental impacts as a consequence of spontaneous fires, by employing Boolean as well as weighted-linear-combination approaches in connection with various fuzzy set functions of population density around the storage sites. Sweden was used as the case study and data from 105 storage sites were analysed; of these, 38 were identified to be posing high risk for downwind residing population. Furthermore, during the past 10 years, the fire frequency and the average population residing within a radius of 1, 2, and 3 km were found to be comparatively higher for storage sites owned by private companies than for those owned by municipalities. The study provided first-cut information of poorly sited temporary storage sites and can help in formalizing the comprehensive risk analysis in the future.     

Nanoparticles in mitigating gaseous emissions from liquid dairy manure stored under anaerobic condition

A number of mitigation techniques exist to reduce the emissions of pollutant gases and greenhouse gases(GHGs) from anaerobic storage of livestock manure. Nanoparticle(NP)application is a promising mitigating treatment option for pollutant gases, but limited research is available on the mode of NP application and their effectiveness in gaseous emission reduction. In this study, zinc silica nanogel(ZnSNL), copper silica nanogel(CuSNL), and N-acetyl cysteine(NACL) coated zinc oxide quantum dot(Qdot) NPs were compared to a control lacking NPs. All three NPs tested significantly reduced gas production and concentrations compared to non-treated manure. Overall, cumulative gas volumes were reduced by 92.73%–95.83%, and concentrations reduced by 48.98%–99.75% for H_2S, and 20.24%–99.82% for GHGs. Thus, application of NPs is a potential treatment option for mitigating pollutant and GHG emissions from anaerobically stored manure.