Carbon monoxide electricity from oxidation

An improved approach from the point of view of thermal efficiency is the electrothermal process in which the mixture of zinc oxide and carbon, in the form of briquettes, are heated in a vertical shaft furnace using the electrical resistance of the briquettes to allow for internal electrical heating. The zinc vapour and CO(g) which are evolved are passed tluough a separate condenser, the carbon monoxide being subsequently oxidized in air. 

Although the occupational human health impact of bioelectricity is smaller than that of coal-fired electricity, the overall human health impact of bioelectricity is higher than that of electricity because of the large contribution of environmental human health impact (Table 14.7). In both systems, the environmental human health impacts come from the emission of carbon monoxide, methane, and sulfur oxides. The hotspots are also similar for the two product systems, because most of these emissions come from the electricity and bioelectricity generation stages. However, the contributions of these emissions are a htde bit different, as sulfur dioxide from coal contributes mostly to human health impacts of electricity, while in the bioelectricity product system there is a small difference in contribution of carbon monoxide and sulfur oxides to human health impact. Fig. 14.5 represents the contributions of main emissions to environmental human health impact for the two product systems. 

Metafile arsenic can be obtained by the direct smelting of the minerals arsenopyrite or loeUingite. The arsenic vapor is sublimed when these minerals are heated to about 650—700°C in the absence of air. The metal can also be prepared commercially by the reduction of arsenic trioxide with charcoal. The oxide and charcoal are mixed and placed into a horizontal steel retort jacketed with fire-brick which is then gas-fired. The reduced arsenic vapor is collected in a water-cooled condenser (5). In a process used by Bofiden Aktiebolag (6), the steel retort, heated to 700—800°C in an electric furnace, is equipped with a demountable air-cooled condenser. The off-gases are cleaned in a sembber system. The yield of metallic arsenic from the reduction of arsenic trioxide with carbon and carbon monoxide has been studied (7) and a process has been patented describing the gaseous reduction of arsenic trioxide to metal (8). 

Human-made sources cover a wide spectrum of chemical and physical activities and are the major contributors to urban air pollution. Air pollutants in the United States pour out from over 10 million vehicles, the refuse of over 250 million people, the generation of billions of kilowatts of electricity, and the production of innumerable products demanded by eveiyday living. Hundreds of millions of tons of air pollutants are generated annu ly in the United States alone. The five main classes of pollutants are particulates, sulfur dioxide, nitrogen oxides, volatile organic compounds, and carbon monoxide. Total emissions in the United States are summarized by source categoiy for the year 1993 in Table 25-10. 

Current US primary energy consumption is about 102 exajoules (EJ) (97 Quads) and is expected to increase to >137 EJ (130 Quads) by 2020. Transportation fuels produced from oil are projected to account for nearly one-third of the projected energy use by 2020, with nearly 68% of the oil imported from unstable and/or unfriendly countries, resulting in a trade imbalance of more than 206 billion (US in 2001). Additionally, the use of fossil fuels for transportation and electricity is a significant contributor of greenhouse gasses such as carbon dioxide, nitrogen oxides, and carbon monoxide (1-4). 

The calcium oxide is produced immediately prior to reduction from high purity limestone. This enthalpy of the reaction is +465.6kJ/mol and is provided by electric power and results in the consumption of Soderberg electrodes made from anthracite. The cell is tapped to release the molten carbide which is produced in 80% purity. The off-gas from the cell is typically 80% carbon monoxide and about 10% hydrogen. Following the production of calcium carbide, acetylene is produced by addition of water to the carbide ... 

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