Catalytic oxidizer system

Design nd Operation. The destruction efficiency of a catalytic oxidation system is determined by the system design. It is impossible to predict a priori the temperature and residence time needed to obtain a given level of conversion of a mixture in a catalytic oxidation system. Control efficiency is determined by process characteristics such as concentration of VOCs emitted, flow rate, process fluctuations that may occur in flow rate, temperature, concentrations of other materials in the process stream, and the governing permit regulation, such as the mass-emission limit. Design and operational characteristics that can affect the destmction efficiency include inlet temperature to the catalyst bed, volume of catalyst, and quantity and type of noble metal or metal oxide used. 

Catalytic oxidation systems are normally designed for destmction efficiencies that range from 90 to 98% (27). In the early 1980s, typical design requirements were for 90% or higher VOC conversions. More recently, however, an increasing number of appHcations require 95 to 98% conversions to meet the more stringent emission standards (20). 

Performance criteria for SCR are analogous to those for other catalytic oxidation systems NO conversion, pressure drop, catalyst/system life, cost, and minimum SO2 oxidations to SO. An optimum SCR catalyst is one that meets both the pressure drop and NO conversion targets with the minimum catalyst volume. Because of the interrelationship between cell density, pressure drop, and catalyst volume, a wide range of optional catalyst cell densities are needed for optimizing SCR system performance. 

T. G. Otchy and K. J. Herbert "First Large Scale Catalytic Oxidation System for PTA Plant CO and VOC Abatement," paper presented at the... 

A catalytic oxidation system may cost 150 per car, but the catalyst cost is estimated to be 30, less than 1% of the cost of an automobile (2). In a few years, the gross sale of automotive catalysts in dollars may exceed the combined sale of catalysts to the chemical and petroleum industries (3). On the other hand, if the emission laws are relaxed or if the automotive engineers succeed in developing a more economical and reliable non-catalytic solution to emission control, automotive catalysis may turn out to be a short boom. Automotive catalysis is still in its infancy, with tremendous potential for improvement. The innovations of catalytic scientists and engineers in the future will determine whether catalysis is the long term solution to automotive emissions. 

T0383 Huntington Environmental Systems, Econ-Abator Catalytic Oxidation System T0384 Hydraulic Fracturing—General... 

T0374 Horizontal Technologies, Inc., Linear Containment Remediation System T0383 Huntington Environmental Systems, Econ-Abator Catalytic Oxidation System T0398 lEG Technologies Corporation, Vacuum Vaporizer Well (UVB)... 

The SRCO catalytic combustion unit treats volatile organic compound (VOC) laden process exhaust air. SRCO stands for self-recuperative catalytic oxidizer. The SRCO can be furnished as a complete operating vacuum extraction and catalytic oxidation system or as a stand-alone catalytic oxidizer to interface with an existing vacuum extraction and/or air stripper system. HD-SRCO stands for halogenated destruction self-recuperative catalytic oxidizer. This system is basically the same as the SRCO system, except that it remediates halogenated hydrocarbons using a different catalyst. 

Costs for catalytic oxidation systems are often included as a part of the entire remedial activity. Typical operating costs for a catalytic oxidation system alone, operating at 100 to 200 standard cubic feet per minute (scfm), will range from 8 to 15 per day (for natural gas or propane-fired systems) to 20 to 40 per day (for electrically heated systems). Capital costs of equipment operating at throughputs of 100 to 200 scfm are estimated to be in a range from 50,000 to 100,000 (D16641Q, p. 7). 

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 HD CatOx system treats vapor emissions contaminated with halogenated volatile organic compounds (VOCs). HD CatOx is a trade acronym for the term halohydrocarbon destruction catalytic oxidation system. This system is based on the use of a proprietary catalyst for a... 

The CO P catalytic oxidation system is a complete prefabricated unit used to treat wastewater contaminated with volatile organic compounds (VOCs) and high biological oxygen demand and chemical oxygen demand. The system uses ozone, ultraviolet light, and hydrogen peroxide to create hydroxyl radicals used in oxidation. 

In the development of effective catalytic oxidation systems, there is a qualitative correlation between the desirability of the net or terminal oxidant, (OX in equation 1 and DO in equation 2) and the complexity of its chemistry and the difficulty of its use. The desirability of an oxidant is inversely proportional to its cost and directly proportional to the selectivity, rate, and stability of the associated oxidation reaction. The weight % of active oxygen, ease of deployment, and environmental friendliness of the oxidant are also key issues. Pertinent data for representative oxidants are summarized in Table I (4). The most desirable oxidant, in principle, but the one with the most complex chemistry, is O2. The radical chain or autoxidation chemistry inherent in 02-based organic oxidations, whether it is mediated by redox active transition metal ions, nonmetal species, metal oxide surfaces, or other species, is fascinatingly complex and represents nearly a field unto itself (7,75). Although initiation, termination, hydroperoxide breakdown, concentration dependent inhibition... 

The cross-coupling with acylperoxyl radicals was shown to lead to high-valent metal species and reactive organic intermediates (144). The Craq002+/CMe3C(0)00 reaction appears to be the sole example of such chemistry reported so far. Extension to other metals and types of radicals is essential before one can even begin to understand whether such reactions take place in catalytic oxidation systems and/or in aerobic organisms, and whether or how to exploit or suppress them. 

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