Waste air treatment

HDN-Technik GmbH (Rednitzhembach, Germany), K. W. Hofmann information concerning odor abatement (gaseous systems) and waste air treatment and a photograph of a photoreactor. 

Because of the new concept of collection of waste air from viscose production, the spinning machines, stretching and tow washing, and subsequent waste-air treatment, today most of the carbon disulfide can be recovered from the waste gas. 

Implementation of waste air treatment as a secondary measure in paint application facilities... 

The need for waste air treatment can generally be avoided by replacing conventional, high-solvent paints by low-solvent coatings. In some cases smaller waste air treatment plants may be necessary for specific demarcated areas where, for example, a solventborne layer is applied. 

Deshusses MA (1997) Biological waste air treatment in biofilters. Curr Opin Biotechnol 8 335-339... 

Selected physical properties of oxygen are included in Table 9.24. It is a colourless, odourless and tasteless gas which is essential for life and considered to be non-toxic at atmospheric pressure. It is somewhat soluble in water and is slightly heavier than air. Important uses are in the steel and glass industries, oxyacetylene welding, as a chemical intermediate, waste-water treatment, fuel cells, underwater operations and medical applications. 

Wastewater treatment plants are also a significant source of refinery air emissions and solid wastes. Air releases arise from fugitive emissions from the numerous tanks, ponds, and sewer system drains. Solid wastes are generated in the form of sludges from a number of the treatment units. 

An air monitoring study at a waste-water treatment plant in Australia found time-averaged hydrogen sulfide levels of 1-2 ppm near the primary clarifiers and inlet structure, and levels <1 ppm at various other locations in the 10-hectare plant site (Koe 1985). 

The environmental fate of chemicals describes the processes by which chemicals move and are transformed into the environment. Environmental fate processes that should be addressed include persistence in air, water and soil reactivity and degradation migration in groundwater removal from effluents by standard waste-water treatment methods and bioaccumulation in aquatic or terrestrial organisms. 

Naf, C., Broman, D., Ishag, R., Zebuhr, Y., PCDDs and PCDFs in water, sludge and air samples from various levies in a waste water treatment plant with respect to composition changes and total flux, Chemosphere 20,1990,1503-1510. 

Environmental risk assessment examines the potential adverse effects to ecosystems from exposure of the aquatic, terrestrial and air components. Initial assessment normally focuses on the aquatic compartment, including effects on microorganisms in waste water treatment plants. This first tier risk assessment can be extended to cover the sediment part of the aquatic compartment and the soil compartment. At higher tonnage levels, effects relevant to the food chain are evaluated, i.e., secondary poisoning. Diderich in Chapter 8 of (73) discusses the principles of EU environmental risk assessment. 

Exposure Levels in Environmental Media. All humans are exposed to at least low levels of chloroform via inhalation of contaminated air, and most humans are exposed by drinking contaminated water. Estimates from intake via inhalation and ingestion of drinking water, based on limited data, are available (see Section 5.5). Exposure from foods cannot be estimated, due to the lack of data. Current information on exposure to chloroform from water, air, and foods, especially for workers or people who live near manufacturing and use facilities, water and waste water-treatment plants, municipal and industrial... 

Municipal waste water treatment plant. Consider a municipal water treatment plant for a small community (Fig. Pl.l). Waste water, 32 000 m3/day, flows through the treatment plant with a mean residence time of 8 hr, air is bubbled through the tanks, and microbes in the tank attack and break down the organic material... 

A minor part of mined fossil fuels is used as a raw material for the chemical industry (e.g., plastics, synthetic fabrics, carbon black, ammonia, and fertilizers). The major part supplies the energy needs for modem society. Fossil fuels supply about 86% of global primary energy consumption (39% oil, 24% coal, and 23% natural gas), providing energy for transportation, electricity generation, and industrial, commercial, and residential uses (El A 2001). Coal, and to a lesser extent oil, combustion leaves a significant amount of solid waste. The treatment of solid waste from fossil fuel combustion is treated in different chapters of this book. In this chapter we focus on air emissions of fossil fuel combustion, and their impact on human health and the environment. 

Clean air is an important prerequisite for sustainable development and is a basic requirement for human health and welfare. In addition, air pollutants contribute to atmospheric problems such as acidification and global climate change, which have impacts on crop productivity, forest growth, biodiversity, buildings, and cultural monuments. The benefits from the progress made in the areas of waste gas treatment and environmental legislation are partially offset by industrialization, an increase in the number of private cars in use, and overpopulation. 

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