Flue-gas desulphurization

Applicattoiis of the device include fractionation of blood plasma, isolation of enzymes from muscle extracts and the separation and concentration of platelet cells from red blood. 

One of the major atmospheric pollutants is sulphur dioxide, which is released during combustion of sulphur-containing fuels, particularly at coal- and oil-fired power stations. Sulphur dioxide has been associated with acid ratn which attacks building materials, steelwork and possibly woodland. It is obviously important to substantially remove sulphur dioxide from flue gases prior to discharge. 

Traditional treatment has largely involved treatment with lime, producing gypsum. Unfortunately, Such a process involves large quantities of both chemicals which then require disposal a considerable amount of waste water is also produced.  

Following research under the European Economic Community s hydrogen programme (1977 1980), a more attractive treatment technique, the 1SPRA Mark XIH A process, has been developed. This process (Fig. 7.25) involves removal of SO via reaction with bromine in the solution phase  

The bromine is generated from hydrobromic acid via electrolysis  

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Merrick, 1989. David Merrick and Jan Vernon, "Review of Flue Gas Desulphurization Systems," Chemistry and Industry, February 6, 1989. 

PF, pulverised fuel fgd, flue gas desulphurization IGCC, integrated gasification combined cycle ... 

Langenkamp, H. and Van Velzen, D., Flue-gas Desulphurization by the Ispra Mark 13 Process. The European Commission, Ispra, Italy, 1988. 

Flue gas desulphurization (FGD) is postcombustion technology that cleans gases after they leave the boiler or combustion zone. The basic approach to cleaning flue gas is to react alkaline minerals with the gaseous S02. Calcium is the principal alkaline sorbent used, although Mg or K are also used. Slurry made from limestone and water, or lime and water,... 

Bottom ash from power stations is less of a problem compared with fly ash for the contamination of natural waters firstly because the proportions of fly ash to bottom ash are approximately three to one and a greater proportion of the bottom ash is used (ECOBA 2003). Secondly, the volatile elements are depleted compared with fly ash (Clarke Sloss 1992). Other combustion residues include fluidized-bed boiler ashes and the products from flue gas desulphurization (FGD). The non-regenerable FGD systems commonly use limestone, slaked lime, or a mixture of slaked lime and alkaline fly ash that are sprayed into the flue gases to remove SO2 (Clarke Sloss 1992). Although 90 wt% of the product is used to replace natural gypsum in plasters and wallboards, there is currently a small excess production in Europe of that is disposed of in landfill and equivalent sites (ECOBA 2003). Because the FGD plant treats the cooled flue gases volatile elements are concentrated and there will be similarities with fly ash. 

FAA FA FBC FC FEBEX FFFF FGD FP FSU FT FTIR FUETAP Flame atomic absorption Fly ash Fluidized bed combustion Filter cake Full-scale engineered barriers experiment (in crystalline host rock) Flow-field flow fractionation Flue gas desulphurization Fission products Former Soviet Union Fourier transforms Fourier transformed infrared spectroscopy Formed under elevated temperature and pressure... 

In flue gas desulphurization systems, equipment such as absorber towers, demister supports, gas outlets, recycle and process pipings, process tanks, and agitators are highly exposed to corrosive and abrasive environments. Chlorobutyl rubber of 60 Shore A... 

Rubber Compound Development for FGD (Flue Gas Desulphurizing) Systems [8]... 

Some convention is employed in the sources of AS, mainly for the benefit of statisticians, who try to follow developments in the AS business. AS that is obtained from caprolactam or acrylonitrile manufacture is normally referred to as co-product. On the other hand, AS that is produced from coke ovens, flue gas desulphurization, smelter tail gas, sewage treatment, gypsum, waste acid from methyl methacrylate and from other chemical processes is usually termed byproduct241. 

Graf. R. "First operating experience with a dry flue gas desulphurization (FGD) process using a circulating fluid bed (FGD-CFB), in "Circ. Fluid. Bed Technol. (Basu, P., and Prabir, X., eds.), pp. 317-27. Pergamon, Toronto (1986). 

Graf, Rolf. Riley, John D., and Erdoel Kohle. "Dry/semi-dry flue gas desulphurization Lurgi circulating fluid bed absorption process, Erdgas, Petrochem., Vol. 40, pp. 263-8 (1987). 

The SVZ plant produces synthetic gas or fuel gas at atmospheric or elevated pressure, with the recovery of minerals in slag. There is a partial gas conditioning (CO shifting), a gas pnrification system with flue gas desulphurization. This plant is characterized by a high thermal efficiency and a flexible feedstock. A 120 000 t/a methanol plant is associated with it. 

Downstream the air preheater fly ash is collected by means of the electrostatic precipitators. Via a heat exchanger and flue gas desulphurization, the flue gas is passed to the stack. The SCR catalyst used in this way is in the so-called high dust mode. This means that the resistance of the catalyst against attrition should be very high. That is one of the reasons for using titania as a support. 

Bulewicz, E.M. Janicka, E. Catalytic effect of NaCl on flue-gas desulphurization by limestone-based sorbents during the FB combustion of coal. J. Inst. Energy 1990, 63, 124-130. 

Dennis, J.S. Hayhurst, A.N. Alternative sorbents for flue-gas desulphurization, especially in flui-dized-bed combustors. J. Inst. Energy 1989, 62, 202-207. 

Honnen et al. [121] found reversible deactivation of SCR catalysts downstream a flue gas desulphurization plant of a waste incinerator. The SO2 concentration varies from 40 to 80mgm and results in the formation of ammonium sulfates at temperatures below 600 K. These sulfates could be removed easily by heating the catalyst to a temperature of about 660 K. 

Hastelloy C276 N10276 59Nil6Crl6Mo5Fe4W Components in chemical, and petrochemical, organic chloride processes, pulp and paper industry, food processing, flue gas desulphurization. 

Inconel 625 N06625 63Ni22Cr9Mo2Fe4(Nb+Ta) High-strength components, in seawater, oil/gas production where H2S and S exist above 150 C, flue gas/flue gas desulphurization, flare stacks offshore, hydrocarbon proc. ... 

Masters, K., Spray drying in environmental control with special reference to flue gas desulphurization, Drying 80, Vol. 2, A.S. Mujumdar, ed., Hemisphere, New York, 1980, pp. 401 04. 

Klaassen R, Jansen AE. Achieving flue gas desulphurization with membrane gas absorption. Filtration Sep 2003 40 26. 

The new technology of coal combustion in fluidized bed has been implemented in some power plants, recently. The temperature of this process is much lower, about 900 °C, thus its phase composition and properties are totally differenL At low combustion temperature only the dehydroxylation of clay minerals occurs and the produced amorphous substance is one of the main components of fluidized bed ash [106] (Fig. 7.20). Simultaneously with coal combustion the flue gas desulphurization is performed and the sorbent, usually calcium carbonate, is introduced into the fluidized bed. Becarrse that the excess amount of sorbent must be added (Ca/S... 

Wallach, D.L. (1997) Ammonium sulphate as a by-product in flue gas desulphurization. ACS Symposium Series No. 668, 244-254. 

The inorganic constituents of coal are often expressed in the form of ash yield and sulfur content. It is, however, often necessary to express an inorganic constituent relative to environmental emissions, such as the amount of sulfur dioxide produced during combustion (Chapters 14 and 15). Furthermore, many of the elements that may be of environmental concern occur in the fly ash after coal combustion (Chapter 14) and, in the case of power plants using flue gas desulphurization (FGD) systens, in the FGD (or scrubber) by-products (Chapter 15). 

Kreysa, G., Bisang, J. M., Kochanek, W., Linzbach, G. (1985). Fundamental studies on anew concept of flue gas desulphurization. Journal of Applied Electrochemistry, 15, 639—647. http //dx.doi.Org/10.1007/BF00620559. 

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