Scrubber flue gas

Flue gas handling Flue gas scrubber Flue-gas scrubbers Flue-gas scrubbing FlueUite Fluent... 

Figure 15. Example of a packaged flue gas scrubber system.

Increasing concern over environmental pollution from sulphur-bearing flue gases has led to the development of new and improved nickel alloys for flue gas scrubber systems (e.g. the Ni-Cr-Fe-Mo alloys in Table 4.21). 

An application in power production, particularly in coal-fired power plants, is the analysis of flue gas scrubbers which remove excess SO2 following coal combustion. Tests run by SAMBESRL at the EPA s Research Triangle Park facility (8,9) have demonstrated the effectiveness of IC in determining sulfite and sulfate in flue gas desulfurization systems. Table III gives results of direct IC analysis of scrubber liquors compared with turbidimetric and titration methods. 

More than 80% of all sodium chlorite produced is used for the generation of chlorine dioxide. Sodium chlorite is also used in disinfectant formulations and sterilization. Like chlorine dioxide, it must be registered with EPA under FIFRA for each specific application use as a disinfection. Sodium chlorite is used in other industrial settings in NO and SO combustion flue gas scrubber systems in the treatment and removal of toxic and odorous gases such as hydrogen sulfide and mercaptans and as a solution formulation to oxidize copper surfaces in multilayer circuit boards (Kaczur and Cawlfield 1993). 

Flue gas scrubbing also has high capital and operating costs associated with it, but also offers PM control. An additive-only solution is almost always the least expensive option when including both capital and operating expenses for SO, reduction depending on the feed sulfur. SO, reduction additives can also be effectively used in conjunction with one of the other solution options. For example, several refiners with FCC feed hydrotreaters use a SO, reduction additive to trim the SO, emissions to the required 25 ppm level rather than to hydrotreat the FCC feed more severely or to install a flue gas scrubber. The optimum choice for a given unit is often site specific. 

Table II. Raman Shifts and Relative Molar Intensities of Some Species Involved in Flue Gas Scrubbers...

This result is important in modeling wet S0x-N0x flue-gas scrubbers. It shows that whereas N02 will oxygenate SO 2 " rapidly, it will not initiate the free-radical autoxidation of sulfite (1 7) Further, since the slightly soluble gas NO is the product, this reaction could reduce the efficiency of N0X removal (unless an NO scavenger is added). 

In real-world systems, ranging from atmospheric droplets to flue-gas scrubbers, reactions take place over a wide range of pH, temperature, and ionic strength. Computer modeling incorporating the free radical chemistry of S02 autoxidation needs to be applied to these systems to identify gaps in our knowledge and determine which reactions deserve further study. These models should provide... 

Minor uses of vanadium chemicals are preparation of vanadium metal from refined pentoxide or vanadium tetrachloride liquid-phase organic oxidation reactions, eg, production of aniline black dyes for textile use and printing inks color modifiers in mercury-vapor lamps vanadyl fatty acids as driers in paints and varnish and ammonium or sodium vanadates as corrosion inhibitors in flue-gas scrubbers. 

Fossil fuels Corrosion due to SO2 in coal-fired power plants Flue gas scrubber system eliminates S02... 

If additional systems such as flue gas scrubbers must be fitted to allow the waste to be combusted, then the waste stream value should be discounted to recover the extra cost. 

Shoop, K.J. Blystone, S.S. Kawatra, S.K. Zeta potential measurements of the components of wet flue-gas scrubber sludge. In Proceedings of the 1996 SME Annual Meeting, Phoenix, AZ, Preprint No. 96-99, 1996. 

Mustard Mustard is immediately destroyed at temperatures above 500°C to S02, HQ, C02 and water vapor. The contractor operated a commercial, transportable 7 MM Btu/hr incinerator which could readily achieve an organic destruction efficiency of 99.9999% and which was used to destroy frozen bulk mustard introduced as solid waste and to thermally treat agent-contaminated metal scrap. The incinerator incorporated a two-stage combustion process, e.g., a rotary kiln (900°C, 1.5 tonnes/hr capacity) and a down-fired secondary combustion chamber (1200°C, 2.5s residence time), backed by a venturi wet flue gas scrubber. System components were erected on a prepared concrete foundation and housed in a prefabricated building to provide shelter for the equipment and operators. Natural gas from a nearby well provided a fuel source. 

This describes the specific curing behavior of fly ash, cement dusts, and certain steel works byproducts, is based on the reaction of silicate and aluminous materials with quick lime. Here too, as with the above-mentioned additives, a higher pH causes the precipitation of metal hydroxides and carbonates. The British SEALOSAFE-Process uses fly-ash plus Portland cement, or alkali silicate glass and Fe/Al hydroxides to solidify a broad spectrum of wastes. In the POZ-O-TEC-Process, the wastes from flue gas scrubbers are solidified together with grate ash and fly-ash. The pozzolanic processes have the advantage of excellent longterm stability however, the products solidify rather slowly and are susceptible to acids. 

Neutralization of oxychlorination reaction water, wastewater of ElXi acidic wash, surficial wastewater, or acidic wastewater from flue gas scrubber of heavy ends-tar incineration. 

Also, as precombustion sulfur removal becomes an attractive alternative to flue gas scrubbers, scientists have explored several methods of removing inorganic sulfur from coal and coal chars. Oxidation, microbial oxidation/desulfurization, and halogenation are avenues that are now, and have been, under investigation for some time (Thomas, 1995). 

FGD material Solid/semisolid material obtained from flue gas scrubbers Fine to coarse (dry or wet) 350 Ca, S, Si, Fe, Al ... 

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