The overall goal of this project was to produce a working dynamic model to predict the transformation and partitioning of trace metals resulting from combustion of a broad range of fuels. The information provided from this model will be instrumental in efforts to identify fuels and conditions that can be varied to reduce metal emissions. Through the course of this project, it was determined that mercury (Hg) and arsenic (As) would be the focus of the experimental investigation. Experiments were therefore conducted to examine homogeneous and heterogeneous mercury oxidation pathways, and to assess potential interactions between arsenic and calcium. As described in this report, results indicated that the role of SO2 on Hg oxidation was complex and depended upon overall gas phase chemistry, that iron oxide (hematite) particles contributed directly to heterogeneous Hg oxidation, and that As-Ca interactions occurred through both gas-solid and within-char reaction pathways. Modeling based on this study indicated that, depending upon coal type and fly ash particle size, vaporization-condensation, vaporization-surface reaction, and As-CaO in-char reaction all play a role in arsenic transformations under combustion conditions.

Combustion Emissions: Formation, Reaction, and Removal of Trace Metals in Combustion Products presents the latest scientific knowledge on combustion, with a particular focus on the behavior of elements in this high temperature method of energy generation. The book describes methods of control and establishes a solid base of understanding for future research. Encyclopedic in style and consistent in format, each chapter systematically presents a complete analysis of the combustion behavior of each element and guides the reader in resolving specific problems. This includes source levels in fuels and fuel usage, emission and pollutant release into the environment and environmental effects, and more. Societal impacts and environmental concerns are considered throughout, highlighting sustainability aspects across a diverse range of applications, such as within power plants, automobiles and propulsion. Presents the latest research in a very systematic way Includes methods of control and establishes a base of understanding for future research in energy systems Analyzes the individual behavior of 34 elements, considering their chemistry, nature and environmental impacts

This paper deals primarily with the case of vapor-phase burning. Heterogeneous reaction of metal vapor and oxygen (and possibly of volatile oxide species) may take place at the surface of growing oxide smoke particles, in competition with homogeneous gas-phase reaction followed by condensation. The relative importance of the heterogeneous and homogeneous reaction paths is currently the subject of some speculation and controversy. In this connection, a knowledge of the collision efficiency of the heterogeneous reaction was of considerable interest. For the Mg - O2 reaction, an average collision efficiency of 0.075 was previously derived but this value cannot be regarded as very reliable. Results obtained by a recently developed method indicate larger values, probably exceeding 0.3. The mechanism of the reaction of metal vapor and oxygen at the oxide surface is unknown. However, from analogy with chemisorption and catalysis at oxide surfaces, it is found that electron transfer plays an important role, and, under some conditions, may become rate-controlling. Observations of luminescence and of anomalous electron emission during reaction of Mg vapor and oxygen at the oxide surface have provided evidence for electronic excitation in the oxide layer.

"Mercury Emission and its Control in Chinese Coal-Fired Power Plants" focuses on investigating mercury emissions samplings and measurement in Chinese coal-fired power plants, mercury emission estimations and future trends, mercury speciation transformation during coal combustion, mercury control and mercury stability in byproducts. The book not only introduces mercury emissions from actual coal-fired power plants, but also presents studies on the mechanism of mercury emission and its control. This is a valuable reference for engineering thermal physicists, thermal engineers, and chemical engineers. Jinsong Zhou, Zhongyang Luo, and Mengxiang Fang are Professors in the College of Mechanical and Energy Engineering, Zhejiang University, China. Yanqun Zhu is Associate Professor in the College of Mechanical and Energy Engineering, Zhejiang University, China.

Cleaner Combustion and Sustainable World is the proceedings of the 7th International Symposium on Coal Combustion which has a significant international influence. It concerns basic research on coal combustion and clean utilization, techniques and equipments of pulverized coal combustion, techniques and equipments of fluidized bed combustion, basic research and techniques of emission control, basic research and application techniques of carbon capture and storage (CCS), etc. Professor Haiying Qi and Bo Zhao both work at the Tsinghua University, China

An up-to-date overview of the characterization, risk assessment and remediation of mercury-contaminated sites. The book summarizes, for the first time, works from Europe, Russia and the American continent, and review chapters are supplemented by detailed, international case studies.