Fluid bed gasification – Plasma converter process generating energy from solid waste: Experimental assessment of sulphur species

Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed.Notable SO₂ and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO₂’s generation. The response of COS to sulphur in the feed was quite prompt, whereas SO₂ was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO₂ generation. The more reducing gas phase regions above the bed would have facilitated COS – hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.     

Heat illness among high school athletes--United States, 2005-2009

Introduction

Heat illness is a leading cause of death and disability among U.S. high school athletes.

Methods

To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005–2009.

Results

During 2005–2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in ≥ 1 day of time lost from athletic activity, a rate of 1.6 per 100,000 athlete-exposures, and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported.

Conclusions

Consistent with guidelines from the National Athletic Trainers’ Association, to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after sports activities.

Impact of industry

By implementing preventive recommendations and quickly recognizing and responding to heat illness, coaches, athletic trainers, and the sporting community can prevent future deaths.     

Optimized acid rain abatement strategies using ecological goals

This article addresses the use of critical loads in optimized emission abatement strategies. Critical loads represent the maximum tolerable deposition possible without adverse impacts, a limit that is highly spatially variable. As deposition targets, critical loads cannot be satisfied at all receptors in Europe. Consequently, there is a need for alternative criteria that still relate to ecological indicators, yet that are feasible, consistent, and equitable. Two criteria are suggested: the relative critical load coverage and the relative deposition reduction. Deposition goals based on these criteria will guarantee that a specified fraction of ecosystems will attain target loads and thus will be protected from adverse environmental impacts. In areas that cannot achieve target loads with the best available control measures, deposition can be reduced to a specified fraction of the unabated level. Examples are presented that demonstrate their derivation and application of the two criteria. The criteria have been implemented in the European-scale Regional Acidification Information and Simulation (RAINS) model. Results obtained indicate that optimized emission strategies based on critical loads may be similar to emission strategies based on deposition reductions at certain levels of the two criteria. This suggests that it may not be necessary to utilize critical loads to formulate deposition targets. A second example shows the effect of excluding countries from European cost minimization. A country's participation can save costs with moderate deposition targets; however, significant costs can be imposed with low (stringent) deposition targets. These preliminary results have significant implications for multilateral negotiations.     

Work domain analysis for air traffic controller weather displays

INTRODUCTION: Adverse weather conditions have a major impact on National Airspace System (NAS) operations. They create safety hazards for pilots, constrain the usable airspace for air traffic control (ATC), and reduce the overall capacity of the NAS. A system-wide dissemination of weather information to controllers could theoretically improve safety and efficiency. PROBLEM: However, it is currently unclear what weather information would be beneficial for tactical operations. Furthermore, no previous research has empirically evaluated optimal presentation designs for ATC weather displays. Ill-designed weather displays can cause safety hazards by presenting redundant information (i.e., by increasing the cognitive load) and display clutter (e.g., by interfering with the visual extraction of traffic data). METHOD: In the present paper, we outline our use of cognitive work analysis (CWA) techniques for the assessment of weather information needs for terminal controllers. RESULTS: Specifically, we describe how the CWA modeling tools helped us reveal instances in the terminal domain where weather information is lacking or insufficiently disseminated. We used our CWA results to drive the development of weather display concepts and to set up a high-fidelity simulation capability. IMPACT ON INDUSTRY: By means of high-fidelity simulations, we can empirically evaluate controller weather information needs in order to propose weather displays for increased aircraft safety and efficiency of terminal operations.     

A CASE STUDY IN THE IMPLEMENTATION OF THE FEDERAL WATER POLLUTION CONTROL ACT AMENDMENTS1

ABSTRACT: A general model of the policy implementation process is utilized to facilitate a discussion of the way Section 208 of PL 92-500 is being carried out on an areawide basis. A study of four “208 areas” in the “New York-Philadelphia corridor” highlights the operation of several variables used in the model. The varying political and socioeconomic conditions in geographic areas which have similar water quality problems are leading to the evolution of vastly different implementing structures, or institutional arrangements. The analysis suggests that these differences may have important implications for the success of the program in each of these areas. A major underlying theme is that such problems are characteristic of the 208 process nationwide and reflect general difficulties associated with managing water quality in a federal system.     

压入式局部通风工作面风流分布数值模拟研究

笔者应用三维k -ε紊流模型描述压入式局部通风工作面风流的流动过程 ,并采用控制容积法导出了描述流体流动方程的离散化方程式 ;用计算流体力学的方法求得了三维k -ε紊流模型的数值解。采用SIMPLE(压力耦合方程式的半阴解法 )算法解算流场 ;TDMA(三对角线算法 )和Gauss Seidel法结合通过线顺法求解离散方程。利用弱松弛法防止非线性方程组迭代求解过程中的发散现象 ,获得了掘进工作面空间的速度分布 ;并将模拟解算结果与在具有实际尺寸的拱形巷道模型中测得的实验结果进行了对比。数值计算结果与模型实验测定结果非常一致 ,验证了笔者的数学模型和数值模拟方法的正确性。     

车辆超限超载的危害性与治理对策研究

调研了我国公路超载的现状 ,分析了车辆超限超载对于损害公路和桥梁、危害交通安全、扰乱运输市场秩序、污染环境的危害性 ,探讨了超限超载屡禁不止的各种原因 ,指出了治理工作的艰巨性和复杂性 ;通过对美国、韩国、德国、日本、南非等国治理超限超载经验的研究 ,分析了超载中需要处理的几个重要关系 ,据此提出了我国应采取“广泛宣传、统一行动、多方合作、依法严管、把住源头、经济调节、短期治标、长期治本”的 8项对策。     

杭州西湖水体富营养化的控制

本文综述了杭州西湖水体富营养化的状况,并为西湖水体富营养化的控制提出了建议和对策。     

Volatile organic compounds concentration profiles and control strategy in container manufacturing industry: Case studies in China

Volatile organic compounds (VOCs), important precursors of ozone (O₃) and fine particulate matter (PM_2.5), are the key to curb the momentum of O₃ growth and further reducing PM_2.5 in China. Container manufacturing industry is one of the major VOC emitters, and more than 96% containers of the world are produced in China, with the annual usage of coatings of over 200,000 tons in recent years. This is the first research on the emission characteristics of VOCs in Chinese container manufacturing industry, including concentration and ozone formation potential (OFP) of each species. The result shows that the largest amounts of VOCs are emitted during the pretreatment process, followed by the paint mixing process and primer painting process, and finally other sprays process. The average VOC concentrations in the workshops, the exhausts before treatment and the exhausts after treatment are ranging from 82.67–797.46 , 170–1,812.65 , 66.20–349.63 mg/m³, respectively. Benzenes, alcohols and ethers are main species, which contribute more than 90% OFP together. Based on the emission characteristics of VOCs and the technical feasibility, it is recommended to set the emission limit in standard of benzene to 1.0 mg/m³, toluene to 10 mg/m³, xylene to 20 mg/m³, benzenes to 40 mg/m³, alcohols and ethers to 50 mg/m³, and VOCs to 100 mg/m³. The study reports the industry emission characteristics and discusses the standard limits, which is a powerful support to promote VOCs emission reduction, and to promote the coordinated control of PM_2.5 and O₃ pollution.     

武汉市湖泊侵占现状分析与洪涝灾害

湖泊是集提供水源、补充地下水、调节径流、抵御洪涝灾害、改善微小气候等功能为一体的重要水域,是湿地的重要组成部分。分析武汉市湖泊侵占与洪涝灾害现状发现,武汉市湖泊侵占现状严重,面积锐减,从而影响了湖泊在防洪排涝体系中的重要作用,是造成了武汉市历年遭受特大洪涝灾害的原因之一。2016年的洪涝灾害应该进一步敲醒警钟,保护武汉市湖泊资源迫在眉睫。为政府决策部门、职能部门、科研机构保护武汉市湖泊资源提供依据。