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Control of Organic and Inorganic Gaseous Emission
Published in Jeff Kuo, Air Pollution Control Engineering for Environmental Engineers, 2018
Combustion is the process of burning. For a more scientific definition, combustion is a chemical reaction process in which a substance reacts rapidly with oxygen at an elevated temperature. The substance is in a more reduced form and often called the fuel, while the source of oxygen is called the oxidizer. The fuel is typically an organic compound that possesses a heating value. The combustion is a destruction process in which the fuel gets destroyed and the process is exothermic (i.e., energy is released from the reaction). It is often called a thermal oxidation process. We burn fossil fuels, such as coal, natural gas, and gasoline to generate energy for many daily activities. Incineration is a waste treatment process that destroys organic substances in a waste solid, liquid, or gas stream.
Biological Waste Treatment
Published in Syed R. Qasim, Wastewater Treatment Plants, 2017
Biological waste treatment involves bringing the active microbial growth into contact with wastewater so that they can consume the impurities as food. A great variety of microorganisms come into play that include bacteria, protozoa, rotifers, nematodes, fungi, algae, and so forth. A general overview of important microorganisms in biological waste treatment is given in Chapter 3. These organisms, in the presence of oxygen, convert the biodegradable organics into carbon dioxide, water, more cell material, and other inert products. The basic ingredients needed for secondary biological treatment are the availability of (1) mixed populations of active microorganisms, (2) good contact between the microorganism and waste material, (3) availability of oxygen, (4) availability of nutrients, and (5) maintenance of other favorable environmental conditions, such as temperature, pH, sufficient contact time, and so on.
Recycling and Disposal of Waste Plastics
Published in Manas Chanda, Plastics Technology Handbook, 2017
Substantial progress has been made over the last 25 years in the recovery rate of waste plastics as well as in the efficiency of the recycling industry, accompanied by sophisticated sorting and recycling systems developed to automate and upgrade the process. In addition, researches have continued to explore innovative ways to derive more value from waste plastics ranging from plastics conversion to energy to plastics conversion to oil. There are now a number of treatment and disposal methods for waste plastics (although when most people think about waste disposal, it is typically the landfill that comes to mind). Treatment techniques that act to reduce the volume and toxicity of solid waste, transforming it into more convenient form for disposal besides deriving fuel from it, have been developed. The major treatment and disposal methods are thermal treatment, dumps/landfills, and biological waste treatment.
Separation of Cobalt, Nickel, and Copper from Synthetic Metallic Alloy by Selective Dissolution with Acid Solutions Containing Oxidizing Agent
Published in Mineral Processing and Extractive Metallurgy Review, 2022
Thanh Tuan Tran, Hyun Seung Moon, Man Seung Lee
In recent years, the demand for strategic metals like cobalt, nickel, and copper has considerably increased (Elshkaki, Reck and Graedel 2017) due to their applications in various fields such as catalysts (Marafi and Stanislaus 2003), special alloys (Shen, Xue and Niu 2008), and rechargeable batteries (Elshkaki, Reck and Graedel 2017) as their sulfide ores have been depleted (Meshram, Abhilash and Pandey 2018). The recovery of these metals from secondary resources like alloy scraps, magnets, and the end of life batteries can be considered to be sustainable solutions for meeting the demands as well as avoiding the waste of natural resources. Moreover, the recovery processes will also bring benefits to both economy and environment such as minimizing the discharge of waste into the environment and cost for waste treatment or landfill disposal (Dunn et al. 2012; Gaines 2014; Sonoc, Jeswiet and Soo 2015; Velázquez-Martínez et al. 2019).
A genetic-algorithm-aided fuzzy chance-constrained programming model for municipal solid waste management
Published in Engineering Optimization, 2020
Ye Xu, Xin Liu, Xiaoguang Hu, Guohe Huang, Na Meng
Municipal solid waste (MSW) management continues to be a major challenge for urban communities throughout the world (Huang and Chang 2003). This is mainly caused by the rapid increase in waste-generation rates, limited treatment capacities and irrational waste allocation patterns. Along with rapid socioeconomic development, the amount of waste generated has increased significantly. The average growth rate in China is maintained at approximately 3.5%. However, not only are existing treatment facilities almost at full capacity, but also activities such as new construction and capacity expansion of disposal facilities are often opposed and rejected by local authorities and residents owing to limited land resources, unreasonable site selection and potential environmental pollution problems. These facts lead to difficulties in satisfying waste treatment requirements and to potential pollution issues caused by untreated waste. It is therefore a critical problem for waste managers to design and generate a cost-effective waste-flow allocation pattern based on advantageous optimization techniques.
Sustainable supply chain planning for biomass-based power generation with environmental risk and supply uncertainty considerations: a real-life case study
Published in International Journal of Production Research, 2021
Mohammad Fattahi, Kannan Govindan, Mehdi Farhadkhani
Incineration includes the combustion of organic substances in waste materials as a waste treatment process. The combustion process is commercially available and a relatively old method for electricity generation from biomass. Combustion generally includes burning biomass to boil water which powers steam generators that produce electricity (Parkes, Lettieri, and Bogle 2015). The developments of combustion technology for electricity generation in terms of environmental issues are discussed by Beer (2000). It is possible to use combustion for any type of biomass. However, before burning the biomass with moisture content >50%, it should be pre-dried (McKendry 2002). Delivand et al. (2011) discussed the economic feasibility of using combustion for power generation in Thailand.