VOC abatement technologies

Table 1 Applicability of VOC abatement technologies to VOC concentration data adapted from [1]...

Table 3.1. Suitability of various VOC abatement technologies for VOC concentration data adapted from Ref. 1.

Catal3Ttic oxidation has been established as one of the most appropriate technologies for VOC abatement. An assessment of the suitability of catalytic oxidation for hydrocarbon control, along with competing processes, is given in Table 3.2. In the literature there are many studies focusing on the catalytic oxidation of VOCs, however, it is beyond the scope of this work to comprehensively review these studies. Rather we will concentrate on the catalytie total oxidation of simple short-chain alkanes and aromatic compounds as illustrative examples of VOC abatement. 

Catal3dic oxidation as a method for VOC abatement is now a well-established technology, and one which offers sigiuficant advantages over other abatement methods. A wide variety of catalysts have been studied for the total oxidation of common... 

The objective of this chapter is to illustrate the point of view of industry with some applications in volatile organic compound (VOC) abatement (i) vent gases from purified terephthalic acid (PTA) plants, (ii) nitrogen-containing VOC (acrylonitrile), (iii) regenerative oxidation catalyst technology. 

Different aspects of total oxidation processes are reviewed in the first part of the book hydrocarbon oxidation (Chapter 1) and soot oxidation (Chapter 2) for mobile appficafions while oxidation of volatile organic compounds (VOC) is treated in the next five chapters. Chapter 3 provides a general overview of VOC oxidation while chlorinated VOCs are specifically discussed in Chapter 4 and persistent VOC in Chapter 5. Plasma catalysis processes for VOC abatement are reviewed in Chapter 6. Finally, Chapter 7 gives the point of view of industry for the development and applications of catalysis for air depollution technologies. Total oxidation is also used for energy production by combustion processes exemplified in Chapter 8. The last two chapters are devoted to oxidation processes in liquid media by electrochemical techniques (Chapter 9) or more generally as "advanced oxidation processes" for water depollution (Chapter 10). 

PTR-MS has also been used to investigate the emissions from intensive pig production in Denmark [150-152], which is an obvious and often cited cause of foul air in populated rural areas. The highest emissions detected by PTR-MS were found to be associated with hydrogen sulfide and acetic acid. Also in Denmark, PTR-MS was used to quantify and study the temporal variation of gas emissions from a model pig house (scale 1 12.5 of a commercial pig house) under varying ventilation rates [153]. The aim of such model studies is to aid in the development of emission abatement technology. In order to do that, it is first necessary to identify the different factors that can affect the emission of VOCs. Concentrations of two inorganic volatiles (NH3 and H2S) and fourteen VOCs were measured coming from a slurry pit and at the outlet of the model pig house. The fourteen VOCs and their protonated mJz values were methanethiol miz 49), acetone (miz 59), trimethylamine miz 60), acetic acid (m/z 61), dimethyl sulfide m z 63), C4-carbonyls (e.g. 2-butanone) miz... 

The Econ-Abator system is a fluidized-bed catalytic oxidation system. Catalytic fluidized beds allow for destruction of volatile organic compounds (VOCs) at lower temperatures than conventional oxidation systems (typically 500 to 750°F). The technology uses a proprietary catalyst consisting of an aluminum oxide sphere impregnated with chromium oxide. 

The term catalytic combustion generally means a complete oxidation of hydrocarbons to C02 and H20 over solid catalysts. Catalyst technology for air-pollution control such as exhaust gas treatment, abatement of the emission of VOCs, combustion of diesel soot particles, and high temperature combustion have boosted research in catalytic combustion. 

The 1990 Clean Air Act requires the reduction of volatile organic compound (VOC) emissions. All VOC emission sources of 10 tons/year or greater are required to retrofit abatement processes using the best available control technology (BACT). 

More recently, a new technology for NO removal has been proposed as an alternative to SCR. This technology with the trade name SCONOx (8) allows the abatement of NO, CO, and volatile organic compounds (VOC) and is based on a cyclic operation NO are stored on a catalyst/sorber material during the adsorption phase, whereas during the subsequent regeneration phase the adsorbed NO species are reduced to nitrogen. 

A number of technologies are currently used for the abatement of VOCs into the atmosphere. In general, these can be divided into two types those that remove VOCs from aerial effluent, but do not destroy them, and technologies which remove... 

Engelhard Corporation, 1991, Brochure entitled "Engelhard s Catalyst Technology—for VOC Air Pollution Abatement that Meets Everyone s Approval, EC-5249 Rev. 4/91. Environmental Protection Agency (EPA), 1991, Handbook, Control Technologies for Hazardous Air Pollutants, Report No. EPA/625/6-91/014, June. 

Section 6 discussed various techniques to reduce VOC emissions. A number of end-of-pipe solutions are available to producers. It was also said that the adoption of waterbased formulations (i.e. an example of cleaner technology as it minimizes the actual use of solvents) would represent a dramatic step forward in terms of VOC emission abatement. From the interviews it is clear that there is no natural progression from the adoption of end-of-pipe solutions to the introduction of cleaner technologies in the case studied. In short, it seems that the incentives and the capabilities required to implement specific solutions are quite different. 

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