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Ethanol Production and Alcoholic Beverages
Published in Debabrata Das, Soumya Pandit, Industrial Biotechnology, 2021
Distillation: Distillation is a system utilizing a vaporization and condensation process which separates more volatile substances from less volatile substances. There will be a discussion of three methods for spirit distillation as follows.
Plant Security
Published in Frank R. Spellman, Fundamentals of Public Utilities Management, 2020
Volatile organic compounds are a group of highly utilized chemicals that have widespread applications, including use as fuel components, as solvents, and as cleaning and liquefying agents in degreasers, polishes, and dry cleaning solutions. VOCs are also used in herbicides and insecticides for agriculture applications. Laboratory-based methods for analyzing VOCs are well established; however, analyzing VOCs in the lab is time consuming—obtaining a result may require from several hours to several weeks depending on the specific method. Faster, commercially available methods for analyzing VOCs quickly in the field include use of portable gas chromatographs (GC), mass spectrometer (MS), or gas chromatographs/mass spectrometers (GC/MS), all of which can be used to obtain VOC concentration results within minutes. These instruments can be useful in rapid confirmation of the presence of VOCs in an asset, or for monitoring an asset on a regular basis. In addition, portable VOC analyzers can analyze for a wide range of VOCs, such as toxic industrial chemicals (TICs), chemical warfare agents (CWAs), drugs, explosives, and aromatic compounds. There are several easy-to-use, portable VOC analyzers currently on the market that are effective in evaluating VOC concentrations in the field. These instruments utilize gas chromatography, mass spectroscopy, or a combination of both methods, to provide near laboratory-quality analysis for VOCs.
Case Study
Published in Stephen S. Olin, Exposure to Contaminants in Drinking Water, 2020
Chemicals in the water supply are made available for uptake into the body in vapor, aerosol, and liquid phases. Volatile chemicals are at least partially released into the vapor phase, whereas less volatile chemicals will be found mainly in the liquid (water) and aerosol phases. Uptake can occur by ingestion, dermal, and inhalation routes; only the dermal and inhalation routes are considered in this case study.
Carcinogenic and health risk assessment of respiratory exposure to acrylonitrile, 1,3-butadiene and styrene in the petrochemical industry using the US Environmental Protection Agency method
Published in International Journal of Occupational Safety and Ergonomics, 2022
Vahid Ahmadi-Moshiran, Ali Asghar Sajedian, Ahmad Soltanzadeh, Fatemeh Seifi, Rozhin Koobasi, Neda Nikbakht, Mohsen Sadeghi-Yarandi
In recent years, following the growth of industries, the reduction of workplace air quality due to chemicals in the air has been evident. Petrochemical and refining plants are among the industries exposed to work-related organic pollutants due to their operation [1]. Volatile organic compounds (VOCs) are one of the leading causes of air pollution, and due to their high evaporation rate and rapid dispersion in the environment, many people are exposed. Consequently, there are irreversible effects on health in various jobs [2,3]. These compounds also enhance atmospheric oxidation and adversely influence respiratory air quality. The diverse effects of these organic compounds include irritation and the creation of various types of occupational cancers [3–6]. Materials released from the refineries and petrochemicals are mainly composed of a mixture of toxic chemicals such as VOCs (e.g., 1,3-butadiene, acrylonitrile, styrene) [3].
EOQ Model for Exponentially Deteriorating Items with Planned Backorders without Differential Calculus
Published in American Journal of Mathematical and Management Sciences, 2022
The basic EOQ model assumes that the items in the inventory can be stocked indefinitely without any physical loss. Perishable or deteriorating items do not satisfy this assumption; the inventory is depleted by both demand and losses due to deterioration. Exponential deterioration is suitable for items that exhibit a constant rate of deterioration per unit over time. Some examples are highly volatile liquids such as gasoline, turpentine, petrochemical products and alcohol; light bulbs, batteries and some electronic parts; and dry bulk food and chemicals. In order to derive the inventory level and the total cost functions, deteriorating items models require solving differential equations. Furthermore, with exponential deterioration, the resulting inventory level and total cost functions are negative exponential, which do not lend themselves to exact closed-form optimal solutions. There is a need for simple models that can be derived without having to use differential equations and result in intuitive closed-form optimal solutions, so that managers and practitioners in the industry who are not well-versed in mathematical analysis and students who do not know differential calculus can easily understand the analysis and interpret the results.
Decrease in evaporative loss of volatile fuels using new mixture of surfactants
Published in Petroleum Science and Technology, 2021
Fateme Beiranvand, Hesam Najibi
Commonly, the losses of hydrocarbon products are classified into three groups, first: when leakage or emission happened, second: when simultaneous decrease in quality of product and quantitative losses happened and third: when decrease in quality of product without quantitative bulk losses happened. Decrease in hydrocarbon losses is very important from economic and environmental points of view. Since the extraction of oil products is expensive, this problem needs to pay attention. Regardless of hydrocarbon loss, some light hydrocarbons eventually evaporate into the atmosphere, which in addition to the possibility of explosive mixtures with air, pollute the environment (Ahmed and Fakhruddin 2018). Emission of volatile organic compounds (VOCs) to the atmosphere can lead to human diseases; Negative effect on bone marrow and blood function, central nervous system depression, decreased consciousness, headache, increased risk of ischemic stroke and increased risk of cancer (Zhang et al. 2019; Abubakar et al. 2015; Chernyak et al. 2010; Kinawy 2009). Environmental pollution caused by VOCs is one of the most emergent collaboration challenges at the world faces today (Zhang et al. 2021; Zhang et al. 2020; Xiang et al. 2020; Hamzehie and Najibi 2016) and then consequently, improvement of hydrocarbon storage techniques is a major concern.