Processing Exhaust

Air cleaning systems are often used to remove dust or vapors from plant or process exhaust streams. Dust collecting systems such as filters or electrostatic precipitators that handle heavy loads of dust are usually designed to be self-cleaning, but it is stiU. necessary to enter the air cleaner periodically for inspection or repair. Dust deposits inside the equipment are likely to be stirred up and inhaled by unprotected workers. Baghouses are particularly likely to cause exposure because large amounts of dust may be retained in the cloth and released when the bags are handled. 

Calcium carbonate is finding increasing use in flue gas desulfurization. This appHcation by a variety of engineering processes traps the sulfur—oxygen compounds produced in the combustion of coal (qv) (see Coal conversion process Exhaust contdol, industrial Sulfurremoval and recovery). 

Fig. 5. Catalytic system designs (11) of (a) basic VOC catalytic converter containing a preheater section, a reactor housing the catalyst, and essential controls, ducting, instmmentation, and other elements (b) a heat exchanger using the cleaned air exiting the reactor to raise the temperature of the incoming process exhaust and (c) extracting additional heat from the exit gases by a secondary heat exchanger.

Special reactions Haber process, exhaust clean up etc. Hydroformylation of alkenes, methanol carbonylation, asymmetric synthesis etc... 

In order to treat gases exceeding 500°F, an upstream gas cooling device is a necessary addon to the Alka/Sorb system. Also, a secondary scrubber is required to process exhaust gases containing a high load of sulfur oxides. 

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. 

Can recovery mercury contaminants in chloride, sulfide, or oxide forms while preventing the release of sulfur or chlorine into the process exhaust. 

Batch Dyeing. Because of the low substantivity of leuco esters of vat dyes for cellulose, batch processes (exhaustion processes) are rather unimportant. 

Monitoring pollutants in a variety of composition ranges in motor vehicle and chemical process exhaust gases is a major area of research in pollution abatement technology. Low-temperature CO oxidation catalysts are needed for zero emission vehicles, CO gas sensors, selective oxidation of CO in H2 rich streams in fuel cell applications,1,2 and in closed-cycle C02 lasers used for remote sensing in space applications.3"5 Effective oxidation of CO during... 

If the technology is accessible and the cost of applying it is not too great, precombustion removal of potential air pollutants has substantial merit. At this stage the offending substance (or substances) present in the raw material has not as yet been burned or reacted to form the process exhaust gases, which should make recovery easier. 

M. Nakamura et al.. In situ analysis of perfluoro compounds in semiconductor process exhaust Use of Li+ ion-attachment mass spectrometry, J. Vac. Sci. TechnoL, A, 19, 1105, 2001. 

In rubber processing, exhaust air is produced in the following process steps [1] ... 

Another usable by-product is the process exhaust air of aPEM-FC or HT-PEM-FC which accumulates at the cathode side. Because half of the oxygen in the intake air reacts with the hydrogen only 10.5 % oxygen remains in the exhaust stream. The remaining gas of the exhaust is mostly nitrogen. This oxygen concentration is so low that in such an atmosphere the majority of substances cannot bum [20]. Since no further reactants than water is in the exhaust gas, it is not poisonous. Further explanations are in Chap. 8. 

What monitoring will be installed to monitor the process, exhaust, or control device ... 

Performance of KPR Systems Processing Exhaust Gas from Paint Spray Booths... 

In addition, solid particles in the feed stream can cause plugging of fixed beds of catalyst. In processing exhaust air streams containing VOCs, the presence of halogens is normally the most significant problem. Particulates, if present, can be filtered from the gas stream before they reach the catalyst, and the other poisons listed are seldom present in significant quantities in such streams. 

The use of FTIR monitoring methods for HAP, VOC, PFC and HFC emissions for identification and quantification in process exhaust and in clean room air, is discussed. A summary is included of the various protocols, test methods and references for the use of FTIR spectroscopy to generate verifiable data. Results of field trials and laboratory study trials are presented, which demonstrate its value as a monitoring method in the semiconductor industry USA... 

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