Effect of utilization of hydrogen-rich reformed biogas on the performance and emission characteristics of common rail diesel engine

The utilization of renewable gaseous fuels in the diesel engine has gained significant interest in recent years due to its clean-burning nature and higher availability. In this study, hydrogen-rich reformed biogas was used as a gaseous fuel in a common rail diesel engine with diesel as pilot fuel. The hydrogen-rich reformed gas was synthesized through dry-oxidative reforming. The experimentations were performed in the load range from 6 to 24 N m with two different flow rates of gaseous fuel (0.5 and 1.5 kg/h) at a constant speed of 1800 RPM. The effects on engine performance parameters (brake thermal efficiency, brake specific energy consumption, and brake specific diesel consumption), combustion parameters (rate of pressure rise and maximum heat release rate) and emission parameters (Unburnt hydrocarbons, nitrogen oxides, carbon monoxide, and carbon dioxide) were assessed. The induction of gaseous fuel led to an increase in brake thermal efficiency by 10.5%, reduction in brake specific energy consumption by 13.6%, and a reduction of 26.4% in brake specific diesel consumption with a flow rate of 0.5 kg/h when compared to diesel-only mode at 24 N m load. The HC, NO_X and CO₂ emissions were reduced by 18.2%, 7.4% and 1.4% with a flow rate of 0.5 kg/h when compared to diesel-only mode at 24 N m load due to lower availability of carbon content in the combustible mixture. The utilization of renewable fuel like hydrogen-rich reformed biogas has great potential for overcoming the issue related to both biogas and hydrogen in diesel engines. Moreover, the higher diesel substitution also demonstrates the potential for cost-saving and fossil fuel conservation.     

环境中污染源废气检测方法及影响因素分析

对污染源废气监测原理进行了简单分析,阐述了当前我国常用的环境中污染源废气检测方法,并对废气检测影响因素及质量控制进行了深入探究。     

A Method to Measure Emissions from Dryers with Diffuse Leakages, Using Evaporated Water as a Tracer

This paper describes a novel method to measure emission from dryers. The method resolves the known difficulties caused by diffuse emissions, and also solves the problems associated with high moisture content of the drying medium. The basic idea is to use water vapor to determine the exhaust flow, while a dry ice trap is used both to preconcentrate emitted VOCs and to determine the moisture content of the drying medium.     

镧系钙钛矿型氧化物（LaBO3）的催化氧化性能及其净化效果的研究

本文在气相色谱仪联用微反应器装置上,研究了LaBO_3型催化剂中的B位元素对催化氧化活性的影响规律,并进行了程序升温脱附实验。另外,还对LaBO_3型载体催化剂进行了活性筛选,并在柴油机台架上与贵金属Pt/Al_2O_3进行了有害气体净化效果的对比实验。实验结果表明,LaBO_3氧化物中LaMnO_3对CO、CH_4的催化氧化活性最高,且CO、CH_4活性中心并不一致。LaMnO_3/γ-Al_2O_3浸渍微量助化剂后,能使CO在130℃完全氧化,CH_4的氧化温度在300～500℃范围内,LaMnO_3载体催化剂对柴油机有害排放物的净化率很低,浸渍微量助化剂后,净化率提高一倍以上,特别是LaMnO_3/堇青石蜂窝陶瓷,浸渍后的净化效果同贵金属Pt/Al_2O_3接近。     

An integrated system of biological and catalytic oxidation for the removal of o-xylene from exhaust

Biofiltration is an efficient technology for treatment of gaseous waste. Its disadvantages, however, include large volume of bioreactor and slow adaptation to fluctuating concentrations in waste gas. Catalytic oxidation offers a high destructive efficiency at relatively low operating temperature and small unit. A bench scale system integrated with a biofilter and a catalytic oxidation unit for the treatment of gases containing o-xylene was investigated in this study. The catalytic oxidation unit was packed with Cu/Al₂O₃ catalyst. The results showed that 90% of o-xylene could be removed in the biofilter at the load below 38.2 g m⁻³ h⁻¹. High o-xylene concentration in inlet gas resulted in an overload of the biofilter. Using the Cu/Al₂O₃ catalytic oxidation unit, the concentration of o-xylene could be reduced evidently. The combination of the chemical and microbial processes not only led to a high and stable efficiency of o-xylene conversion, but also improved capacity resisting the shock loads. The Cu/Al₂O₃ was studied for o-xylene oxidation in temperature range of 90–320 °C. The o-xylene conversion was improved correspondingly with the increasing of oxidation temperature. The reaction mechanism of o-xylene oxidation on Cu/Al₂O₃ was also investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS).     

汽车排放控制系统中的氧传感器现状及展望

介绍了浓差型(Nernst型)、极限电流型和半导体电阻型等汽车排放控制系统中的氧传感器原理及结构。在综合该领域国内外研究现状的基础上,对氧传感器的发展进行了展望。     

A source apportioned mercury mass balance across a coal-based petrochemical complex

Coal-fired power generation facilities are the largest single anthropogenic source of mercury to the atmosphere. Global mapping of anthropogenic emissions has previously estimated the mercury emission from stationary combustion from South Africa at being 82.6 tonnes per annum, but preliminary in-house calculations have placed this at a significantly lower amount. A petrochemical facility in South Africa, utilising a significant amount of coal in its gasification and steam generation processes, undertook a project to determine a mercury mass balance across the complex, and to apportion the Hg emissions from the facility.     

Pathways to eliminate carbon emissions via renewable energy investments at higher education institutions

Higher education institutions are among the many public and private sector entities that have committed to long-term sustainability goals in response to the threat of climate change. A key challenge for these institutions is establishing a commitment to make targeted investments in renewable energy technologies in support of emissions reduction goals. Such strategies require a vision to simultaneously coordinate strategic investments in renewable energy technologies with tactical operational decisions to achieve the desired benefits. In this paper, we formulate and solve a least-cost renewable energy capacity investment planning model to determine pathways to achieve emissions reduction strategies. Specifically, we apply our model to Rutgers University to evaluate its target of 100 % carbon neutrality. Using these insights, we share recommendations on how these strategies can be executed. This research serves as a springboard for administrators to assess and deploy their emissions reduction strategies, while ensuring system and financial constraints are satisfied.     

Belgian Experiences in the Ozonization of Water

After reviewing the uses of ozone in the preparation of drinking water, high purity water for Pharmaceuticals industries, and swimming pools throughout Belgium, a discussion of technological developments made at the Tailfer plant (serving Brussels) concerning the uses of ozone is presented. These subjects include analytical and monitoring techniques developed for ozone, procedures for ozone contacting employed at this plant, treatment of ozone contactor off–gases, and the use of oxygen–enriched process gas to produce supplemental amounts of ozone required periodically. Capital and operating cost data are presented.