China
Africa
Explore chapters and articles related to this topic
Gas Turbine Spray Combustion
Published in Kenneth M. Bryden, Kenneth W. Ragland, Song-Charng Kong, Combustion Engineering, 2022
Kenneth M. Bryden, Kenneth W. Ragland, Song-Charng Kong
Soot is formed in the fuel-rich zones near the fuel droplets. Most of the soot is produced in the primary zone and is consumed in the intermediate and dilution zones in high-temperature turbines. Injecting more air into the primary zone reduces soot emissions but at the expense of increased CO and HC emissions. Sooting is more severe at high pressure in part because soot is formed closer to the spray nozzles. Soot emissions can be reduced by improved mixing, water injection, and increased residence time.
Global Abatement of Air Pollution Through Green Technology Routes
Published in Shrikaant Kulkarni, Ann Rose Abraham, A. K. Haghi, Renewable Materials and Green Technology Products, 2021
Sijo Francis, Remya Vijayan, Ebey P. Koshy, Beena Mathew
Since pollutants in the air are detrimental to human health, the public health is in crisis in cities. The Clean Air Act of United States Environ-mental Protection Agency (EPA) is to protect public health by regulating the emissions of these harmful air pollutants. The main diseases caused by air pollution include respiratory and cardiovascular-related issues. CO, NO, and soot are the main pollutants detrimental to health. CO attacks hemoglobin and as a result carboxyhemoglobin is formed and the oxygen-binging capacity of blood gets reduced. NO can form additional compounds with hemoglobin and thus enter into the bloodstream. Soot is a particulate matter and contains tiny chemical particles, smoke, dust particles, or other allergens. Contents of smog and soot are almost similar. The smallest airborne particles in soot cause health problems including bronchitis, asthma, heart attacks, irritation to eyes and throat, chronic obstructive pulmonary disease, and even death. Besides the above-mentioned pollutants, toxic components such as polynuclear hydrocarbons which are exhausts from traffic exhausts and wildfire also cause lung irritation, liver issues, and even deadly cancer. In addition to the above man-made pollutants, there are also natural air pollutants. Some allergens from trees, grass, and weeds which are known as pollen and mold also cause air pollution. They are carried by air and are hazardous to health. Although no human activity is involved in carrying these allergens, they are also considered air pollution. Some health issues cause by air pollution are mentioned below.
Application of a Spark Discharge Generator for Production of Combustion-Like Aerosols
Published in Andreas Schmidt-Ott, Spark Ablation, 2019
A lot of work has been done recently to reduce emissions of soot particles, on the one hand, by optimizing the combustion and, on the other, by after treatment devices such as particle traps, electrostatic precipitators, etc. New legal limits have been introduced to consider also very small particles. For combustion engines, a number limit for solid particles >23 nm has been established (PMP protocol, UNECE Regulations No. 83 [36]). This requires also new instrumentation.
A review on the heterogeneous oxidation of SO2 on solid atmospheric particles: Implications for sulfate formation in haze chemistry
Published in Critical Reviews in Environmental Science and Technology, 2023
Qingxin Ma, Chunyan Zhang, Chang Liu, Guangzhi He, Peng Zhang, Hao Li, Biwu Chu, Hong He
Soot originates from incomplete combustion of fossil fuel and biomass, and has significant impacts on the environment, climate, and human health (Novakov & Rosen, 2013). The total global annual emissions were estimated at about 8.54 Tg in 2017(Xu et al., 2021). Due to its high surface area and catalytic activity, soot has been recognized as an important medium for atmospheric heterogeneous reactions (Liu et al., 2022; Nienow & Roberts, 2006). Soot particles were found to internally mix with sulfates in polluted urban environments and in the marine troposphere, which is assumed to be formed by the heterogeneous reaction of SO2 with soot (Buseck & Pósfai, 1999; Pósfai et al., 1999). The heterogeneous reaction between SO2 and soot (carbon-based constituents, such as graphite or black carbon) has also attracted much attention since carbon materials with high adsorption capacity are widely used in the adsorption and removal of SO2 (Lizzio & DeBarr, 1997). Black carbon can catalyze the oxidation of SO2 by O2 to form SO3 or H2SO4 in the presence of H2O. For example, Novakov et al. (1974) reported that graphite and propane soot catalyze the oxidation of SO2 to form sulfates in the presence of O2 and water. Chughtai et al. (1998) proposed the reaction scheme of SO2 on soot to occur as follows: where SS is the surface sites on soot.
A Combined Experimental and Computational Study of Soot Formation in Normal and Microgravity Conditions
Published in Combustion Science and Technology, 2022
Richard R. Dobbins, Jesse Tinjero, Joseph Squeo, Xinyu Zhao, Robert J. Hall, Meredith B. Colket, Marshall B. Long, Mitchell D. Smooke
Combustion-generated soot particulates can pose significant health risks and are the subject of stringent EPA regulations. These particulates also play a role in global warming mechanisms, affecting the transfer of atmospheric radiation and serving as sites for water droplet condensation and cloud formation. Furthermore, they enhance the melting of ice and snow by providing an absorptive surface for sunlight. In combustion, soot contributes to thermal radiation loads on combustion liners and turbine blades, and soot deposition on low observable surfaces can compromise the radar signature of aircraft. In some systems, the linkage of soot production to radiation and bulk flame properties is so strong that a careful treatment of this problem is necessary for quantitative modeling of flame structure. In addition, radiative power loss can be such a considerable fraction of total enthalpy release in sooting flames that the gas temperature and soot formation rates themselves can be significantly altered (Dotson et al. 2011; Hall 1988; Hall, et al. 1997a; Markstein 1985; Mueller and Pitsch 2013; Sivathanu and Gore 1997; Smooke et al. 2004).
Experimental Investigation of Emission Characteristics on Can-Combustor Using Jatropha Based Bio-derived Synthetic Paraffinic Kerosene
Published in Smart Science, 2021
Nand Jee Kanu, Suresh Guluwadi, Vivek Pandey, S Suyambazhahan
Combustion products or emissions from the majority of gas turbines are toxic and poisonous in their effect on humans and the environment. The emissions have different effects, for example, carbon dioxide (CO2) causes global warming. Carbon monoxide (CO) is toxic and hazardous to health. The oxides of nitrogen, collectively called NOx, are the main reason for the continued depletion of the earth’s protective ozone layer, particularly from high altitude emissions from aircraft, as these are not reabsorbed by the atmosphere as is the case with territorial NOx. The water vapor in the atmosphere reacts with NOx and leads to the formation of HNO3, thereby causing acid rain. In addition, the soot particle emissions are dangerous and lead to cardiac and respiratory problems.