Apparatus and process for flue gas desulphurization

#I. Field of the Invention

#The present invention relates to the removal of sulphur and sulphur dioxide components from gas streams, and more specifically to the removal of these and other similar elements from stack gasses and smelter gasses of the type produced from the combustion of hydrocarbons such as coal, etc.

#II. Description of the Prior Art

#Other objects, features and advantages of the present invention will be apparent from a study of the written description and the drawings in which:

#FIG. 1 illustrates a partially cross-sectioned frontal perspective view of a system for removing stack gas effluents in accordance with the present invention.

#FIG. 2 illustrates a frontal view along section lines 2--2 of FIG. 1 showing the construction of the heater coils within the breech.

#A first preferred embodiment of an apparatus in accordance with the present invention is illustrated generally in FIGS. 1, 2 and 3. The apparatus is shown as associated with a typical electrical generating facility of the type employing coal or fuel oil for the combustion process, with the heat furnished from the combustion process being used to superheat water. The steam produced from the superheated water is transferred through high pressure turbines which run the generators for producing electricity. The present invention relates to an improvement for removing SO.sub.x, NO.sub.x and other components from the flue gasses which are produced as a by-product of the combustion process of the fuel oil or coal. While the system as illustrated in the attached drawings is specific in nature, it should be recognized that various modifications will be required in order for the method as disclosed herein to be utilized efficiently with power plant units of various types.

#With specific reference to FIG. 1, a water circulation system, shown generally as 20 in the diagram, includes a riser pipe 22 which generally communicates up the outside of a smokestack 10. A plurality of spray rings including a first spray ring 24, a second spray ring 26 and a third spray ring 28 are all located within the inner cylinder defined within the smokestack 10. Each of the spray rings is generally similar in that the water or other liquid which is transported through the riser pipe 22 will be forced from each of the spray rings under high pressure through standard spray nozzles in order to produce a fine mist throughout the upper volume within the smokestack 10. The purpose of the spray mist is to separate the soluble contaminant and particulate matter from the flue gasses and also to wash down an inside surface of the smokestack 10. The volume of the water or other fluid which is sprayed from the spray rings 24, 26 and 28 must be determined according to the rate of flow of the flue gasses traveling through the smokestack 10 and also the level of contaminants within the flue gasses.

#A lime rock bed, shown generally as 30 in FIG. 1, is located immediately above the third spray ring 28. Multiple spray nozzles 112 located on the third spray ring 28 should be adjusted so as to at least partially moisten the lime rock within the bed 30. The lime rock bed 30 comprises a screen or mesh-type support structure 32 which traverses the entire diameter of the inside surface of the smokestack 10 so that all of the flue gasses passing therethrough must travel through the lime rock 34 located within the support structure 32. The function of the lime rock 34 is to filter and chemically remove any further impurities which may escape the spraying system as previously described.