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Sustainable Energy Production from Distributed Renewable Waste Resources through Major Waste-to-Energy Activities
Published in Vladimir Strezov, Hossain M. Anawar, Renewable Energy Systems from Biomass, 2018
Tao Kan, Vladimir Strezov, Tim Evans
For the most commonly used technology of WtE incineration, the flue gas from waste incineration generally contains particulate matter (PM), elements of S, Cl, F, and N, and components of N2, CH4, CO, NOx, and SO2, volatile organic compounds (VOCs), vaporised heavy metals (e.g., Pb, Hg, and Cd), polychlorinated dibenzodioxines and furans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAH), HCl, HF, NH3, and others (Damgaard et al. 2010, Chen et al. 2017). Total organic carbon (TOC) is also used as a parameter that refers to the total carbon amount of the organic compounds. Table 3.5 lists typical component concentrations (in descending order) in the crude flue gas from MSW incineration after the boiler and before the flue-gas cleaning systems.
Environmental Hazards and Their Management
Published in Danny D. Reible, Fundamentals of Environmental Engineering, 2017
Another means of measuring oxygen demand, the chemical oxygen demand (COD) is measured by refluxing the waste sample with hot potassium dichromate for 2 to 3 h. The primary advantage of this measure of oxygen demand is its rapidity, although the process results in the oxidation of many compounds not normally biodegradable. An even quicker measurement procedure is the combustion of the sample by reaction with oxygen over a catalyst at 900°C. If the oxygen requirements are measured in this manner, the total oxygen demand (TOD) can be estimated. If the rate of evolution of CO2 is measured, the total organic carbon (TOC) can be estimated. Because organic materials provide the largest source of oxygen-demanding compounds, TOC is also a useful measure of oxygen demand. Each of the oxygen demand measures, BOD, COD, and TOD, are generally expressed as milligrams of oxygen required per liter of the waste stream. Historically, oxygen demand by one or more of these measures has been the most important indicator of industrial effluent quality.
Introduction
Published in Jamie Bartram, Richard Ballance, Water Quality Monitoring, 1996
Jamie Bartram, Richard Ballance
Measurement of TOC is a much more rapid means of determining the organic content of water and wastewater than is the measurement of biochemical oxygen demand (BOD). In addition, two of the methods also provide more rapid measurement than the chemical oxygen demand (COD) test. Because of the presence of non-biodegradable organic compounds, BOD is not directly related to total organic carbon, and COD analyses may include reduced inorganic compounds. However, if the relative concentrations of organic compounds in the samples do not change greatly, empirical relationships can be established between TOC and BOD or COD to permit speedy and convenient estimations of the latter. Measurement of TOC can be used to monitor processes for the treatment or removal of organic contaminants without undue dependence on the oxidation states, and is valid at low concentrations.
Drinking water quality and human health risk evaluations in rural and urban areas of Ibeju-Lekki and Epe local government areas, Lagos, Nigeria
Published in Human and Ecological Risk Assessment: An International Journal, 2020
Temitope O. Sogbanmu, Sherifat O. Aitsegame, Olubunmi A. Otubanjo, John O. Odiyo
Most of the physicochemical parameters (EC, turbidity, TDS, chlorides and nitrates) analyzed in water samples from the study areas were below the maximum permissible limits by NSDWQ (2007). However, the pH of water samples collected from rural communities in Ibeju-Lekki was above the recommended maximum limit of 8.5 (NSDWQ 2007). Drinking water with a pH level above 8.5 indicates that high levels of alkaline minerals are present. High alkalinity does not pose a health risk but can cause esthetic problems such as alkali taste to water (WHO/United Nations International Children’s Fund 2010). Also, the mean concentrations of TOC in the study area exceeded the NSDWQ (2007) limit of 5 mg/L. TOC is used as an indicator of the natural organic matter (NOM) and inorganic matter (bromide) in water. All commonly used chemical disinfectants (such as chlorine, chlorine dioxide, chloramines and ozone) react with organic matter and/or bromide to varying degrees to form different disinfection byproducts (DBPs) such as trihalomethanes (THMs). People can be exposed to THMs in drinking water through ingestion of drinking water, inhalation of indoor air largely due to volatilization from drinking water, inhalation and dermal exposure during showering and bathing. THMs are suspected to have negative effects on birth such as low birth weight, intrauterine growth retardation in terms of births as well as gestational age and preterm delivery. THMs have also been found to be carcinogenic and mutagenic with the greatest amount of evidence being related to bladder cancer (Mohamadshafiee and Taghavi 2012).
Treatment of Leather Dyeing Wastewater with Associated Process of Coagulation-Flocculation/Adsorption/Ozonation
Published in Ozone: Science & Engineering, 2018
Bianca Mella, Brunna Samuel de Carvalho Barcellos, Dimitrius Extralazon da Silva Costa, Mariliz Gutterres
The Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) are the most widely used indicators of water/wastewater organic pollution. BOD determination involves the measurement of the dissolved oxygen used by microorganisms in the biological oxidation of organic matter. The reason is that BOD test results are now used to determine the approximate quantity of oxygen that will be required to biologically stabilize the organic matter present, to determine the size of wastewater facilities, to measure the efficiency some treatment processes and to determine compliance with wastewater discharge permits (Sibil, Berkun, and Bekiroglu 2014). COD is the amount of oxygen required to oxidize the organic fraction of a sample, susceptible to oxidation by a strong chemical oxidant under acidic conditions. Total Organic Carbon (TOC) indicates the amount of total organic carbon in an effluent.
Measurement of specific surface area of barite in drilling fluid and its applications
Published in Petroleum Science and Technology, 2022
Di Wang, Zhengsong Qiu, Hanyi Zhong, Xin Zhao, Jian Su, Lijun Fan
Total organic carbon (TOC) is the total amount of organic matter in water expressed by the mass concentration of carbon (mg/L). In order to determine the carbon content of the sample, first configure the sample into solutions with different concentrations, draw the TOC standard curve, and determine the accuracy by fitting the curve. Then, the excess sample is added to the powder suspension and fully stirred to ensure that the powder surface reaches the saturation adsorption of the sample. Finally, the suspension was filtered and dried, and the TOC measurement experiment was carried out on the powder to obtain the adsorption amount of the powder on the sample.