北京首都机场绿色滑行时间估算

采用北京首都机场2014年实际CDM地面放行数据确定航空器的污染物排放量与离场排队飞机数量和落地滑入飞机数量的强关联性,构建包含这两个解释变量为影响因素的多元线性回归模型,用以估算几种常见机型在首都机场地面运行时的最小污染物排放量和绿色滑行时间。对比实际污染物排放量与最小污染物排放量,得出首都机场离场地面污染物排放量远远超过最小污染物排放量。     

Low-carbon transition of iron and steel industry in China: Carbon intensity, economic growth and policy intervention

As the biggest iron and steel producer in the world and one of the highest CO₂ emission sectors, China's iron and steel industry is undergoing a low-carbon transition accompanied by remarkable technological progress and investment adjustment, in response to the macroeconomic climate and policy intervention. Many drivers of the CO₂ emissions of the iron and steel industry have been explored, but the relationships between CO₂ abatement, investment and technological expenditure, and their connections with the economic growth and governmental policies in China, have not been conjointly and empirically examined. We proposed a concise conceptual model and an econometric model to investigate this crucial question. The results of regression, Granger causality test and impulse response analysis indicated that technological expenditure can significantly reduce CO₂ emissions, and that investment expansion showed a negative impact on CO₂ emission reduction. It was also argued with empirical evidence that a good economic situation favored CO₂ abatement in China's iron and steel industry, while achieving CO₂ emission reduction in this industrial sector did not necessarily threaten economic growth. This shed light on the dispute over balancing emission cutting and economic growth. Regarding the policy aspects, the year 2000 was found to be an important turning point for policy evolution and the development of the iron and steel industry in China. The subsequent command and control policies had a significant, positive effect on CO₂ abatement.     

电化学还原-氧化工艺降解4-氯酚的毒性研究

采用紫外光还原法制备了Pd-Fe/石墨烯催化阴极,并以Ti/IrO_2/RuO_2为阳极,构成三电极体系(双阴极)和两电极体系(单阴极)的电化学还原-氧化降解工艺,分别对4-氯酚进行降解.采用离子色谱、高效液相色谱、TOC仪对4-氯酚降解过程中中间产物及其浓度进行测定.根据公式计算降解过程中理论计算毒性值,应用发光细菌法测定降解过程中的实际毒性值,对理论计算毒性值与实际毒性值进行比较,分析不同体系下降解过程中毒性的变化规律.结果表明,两种工艺体系在最佳降解条件下,阴极室毒性均呈下降的趋势,由于降解过程中在阳极室生成高毒性的苯醌,阳极室毒性均先升高后降低.通过相关性分析得到,两种体系理论计算毒性与实际毒性在P=0.01水平下,相关性系数均为1,显著相关,表明降解过程中实际毒性的测定结果真实可靠.降解至120 min时,三电极体系毒性小于两电极体系,表明三电极体系优于两电极体系.据此提出实际毒性测定方法在电化学还原-氧化工艺降解氯酚类有机废水毒性测试的工业应用中有着广泛的前景.     

分类收集蔬菜垃圾与植物废弃物混合堆肥工艺实例研究

以分类收集的生活垃圾(主要为蔬菜垃圾)和破碎树枝为原料,采用条垛式堆肥工艺,在中试规模条件下考察了原料初始含水率、通风频率、翻堆频率、接种比例4种因素对混合堆肥效果的影响.同时,在试验的9种工况下,对温度、氧浓度、有机碳降解率、有机碳氮比(C/N)、腐殖质含量等指标进行测定.结果表明,堆肥42d时各堆体均已达到稳定化要求.经过比较肥分保持、腐殖化程度和能量投入等指标,获得的最优堆肥控制条件为:初始含水率65%,通风频率15min/60min(开/关),翻堆频率为每3d1次,产物接种比例5%.最优控制方案下的主发酵通风率仅为0.03L.min-1.kg-1(以VS计),可实现堆肥过程的低能耗,适合于我国村镇区域的应用条件.     

爆炸超压场景下危化品社会风险对允许规划人口密度的影响分析*

为研究危化品重大危险源基于社会风险基准的规划管控影响,采用我国标准规定的定量风险评价方法,TNT当量炸药简化方法,针对最大TNT当量炸药、事故发生总累计频率、人口密度分布控制参数等不同工况条件,对比分析国土开发强度的允许人口密度受社会风险约束影响的变化规律。研究结果表明:人口密度指数分布控制参数Nk与Nb的允许取值随最大TNT当量炸药和事故发生总累计频率降低而提高;确定工况下,允许总人口规模受最大TNT当量炸药影响很小;在最大TNT当量炸药大于100 t或事故发生总累计频率小于1×10-8次/a时可按最大事故场景进行规划控制分析。     

复杂地下空间交通体系连接匝道烟气控制方案研究

复杂地下空间交通体系作为新型地下交通形式,车流量大且存在多个分合流点,气流组织复杂,防灾排烟难度极大。以杭州某复杂地下空间交通体系连接匝道为研究背景,提出匝道通风排烟设计方法,再选取其中二合一式连接匝道结构,采用FLUENT模拟其两种防灾排烟方案的有效性。模拟结果表明：两个连接匝道末端单独设置排烟口的设计方案可有效保证火源下游车辆和火源上游人员的逃生安全;根据分合流流速分配理论模型,在合流处只设置一个排烟口且排烟量提高40 m³/s时,也可达到同样的防灾排烟效果,从土建成本考虑,推荐此方案,为同类型隧道结构提供借鉴。     

A disaster scene simulation system in 3D for oil transmission stations: Design and implementation

The disaster scene in three-dimensional (3D) plays a crucial role in disaster emergency management and risk communication of oil transmission stations. However, existing research for the disaster scene mainly focuses on reproducing the disaster environment and rarely predicts the damage state of the disaster-affected object. This paper proposes an object-oriented modeling method that utilizes a multilevel decomposition pattern for disaster scenes. This method combines earthquake vulnerability assessment with 3D visualization technology to predict and characterize the damage state of critical infrastructure in oil transmission stations. To enhance earthquake risk perception, a simulation system is designed and developed, which allows for the construction of virtual scenes and quick simulation of disaster scenes in 3D. The case application shows that the system improves the 3D modeling efficiency of disaster scenes and enhances public awareness of earthquake risks. The simulation system can provide technical support for seismic mitigation planning and emergency management decision-making at oil transmission stations and has good application prospects.     

A data-driven narratives skeleton pattern recognition from accident reports dataset for human-and-organizational-factors analysis

Accidents in the process industry involve several interacting factors, including human and organizational factors (HOFs). A long-standing obstacle to HOFs analysis is lack of data. Accident reports are an essential data source to learn from the past and contain HOFs-related data, but they are usually unstructured text in a not standardized format. Some studies have explored the extraction of information automatically from accident reports based on Natural Language Processing (NLP) techniques. However, they were not dedicated to HOFs. Risk communication is considered an essential pillar in safety and risk science. This research develops a HOFs-focused risk communication framework based on the NLP techniques that can support risk assessment and mitigation. The proposed approach automatically extracts the target groups oriented “Who, When, Where, Why” (4Ws) information from accident reports.This framework was applied to explore the eMARS database. The results show that the “4Ws” skeleton of narratives has appreciated performance in pattern recognition and holistic information analysis. The graphical representation interfaces are designed to display the features of HOFs-related accidents, which can better be communicated to the sharp-end operators and decision-makers.     

Simulation of scenario characteristics of LPG tank explosion accident and its contribution to emergency planning: A case study

Leakage and explosion of hazardous chemicals during road transportation can cause serious building damage and casualties, and adoption of highly-efficient emergency rescue measures plays a critical role in reducing accidental hazards. Considering a liquefied petroleum gas (LPG) transport tanker explosion accident that occurred in Wenling, Zhejiang Province, China on June 13, 2020 as example, this study proposes a risk assessment framework. This framework recreates the leakage and explosion of the accident process using FLACS v10.9, suggests plans for evacuation, describes the rescue areas of different levels, and explores the influence of environmental factors on the evacuation and rescue areas. The results show that simulated and predicted distributions of fuel vapour cloud concentration and explosion overpressure can provide a reference basis for rapid rescue activities; the characterization of the dynamic effects of wind speed, wind direction, and temperature with respect to the evacuation and rescue areas can be used as theoretical support for on-site adjustment of rescue forces. The role of obstacles can prevent the expansion of the evacuation areas under low wind-speed conditions, and the presence of highly congested obstacles determines the level of the rescue area. The results obtained are important for the risk analysis and the development of emergency rescue measures in case of explosion accidents associated with transportation of hazardous chemicals on high-hazard and high-sensitive road sections.     

提高污泥碱性发酵挥发酸积累的新方法

为了加大剩余污泥在碱性条件下的水解酸化程度,本研究尝试了两种新的能促进污泥碱性发酵产酸的方式,分别是向批式的污泥碱性发酵系统中投加未灭菌发酵污泥和投加灭菌发酵污泥,结合温度的影响(10℃和35℃)分别考察了这两种方式对污泥水解酸化效果的影响.结果表明,中温有利于水解酶和产酸菌作用的发挥,增大了污泥的水解酸化程度,体系内有明显的挥发酸(VFAs)积累.35℃条件下,两种方式都在很大程度上促进了新鲜污泥的水解酸化程度,经灭菌后的发酵污泥的投加较等量的未灭菌的发酵污泥的投加效果更为显著.前者的水解速率是后者的2倍,发酵末期酸积累量为后者的1.5倍,且前者在较长的发酵时间内VFAs含量维持恒定.分析两种方式能促进污泥水解酸化的原因得到:未灭菌发酵污泥的投加是向系统中引入了一定量的产酸菌,灭菌发酵污泥的投加引入了大量的较易水解的有机底物.水解产物的增加能在更大程度上影响产酸的效果.因此,中温条件下向污泥碱性发酵系统中投加经灭菌处理后的发酵污泥是提高剩余污泥发酵产酸量更为有效的方式.