Abstract: Finely atomized alkaline sorbent salt solutions are injected into a hot flue gas stream to remove SO2. Flash evaporation of the droplets produces very fine dried sorbent particles, which react efficiently with SO2 in the flue gas. The liquid sorbent may be sodium carbonate, sodium hydroxide, sodium sulfite, potassium carbonate, potassium hydroxide or the like. In a coal-fired boiler, the liquid sorbent may be injected after the economizer section, where the flue gas temperature is below 850° F., and upstream of a particulate collection device. The dried sorbent particles react with SO2 and then are removed from the flue gas stream in the particulate collection device, producing a cleaned flue gas stream.

Abstract: Finely atomized alkaline sorbent salt solutions are injected into a hot flue gas stream to remove SO2. Flash evaporation of the droplets produces very fine dried sorbent particles, which react efficiently with SO2 in the flue gas. The liquid sorbent may be sodium carbonate, sodium hydroxide, sodium sulfite, potassium carbonate, potassium hydroxide or the like. In a coal-fired boiler, the liquid sorbent may be injected after the economizer section, where the flue gas temperature is below 850° F., and upstream of a particulate collection device. The dried sorbent particles react with SO2 and then are removed from the flue gas stream in the particulate collection device, producing a cleaned flue gas stream.

Abstract: The installation of one or more prefabricated drains beneath the surface of sediment in a sediment pond utilizing suction or a vacuum to withdraw water from the sediment material to lower the water level down to the level of the prefabricated drains below the pond surface. Dewatering may be coupled with imparting vibrations to the material to further promote both additional dewatering and compaction of the sediment material in the pond. A suitably graded bottom ash, fly ash, sand or large-diameter-solid particle or sediment layer may be added on top of the horizontal drains to enhance dewatering of finer sediment material.

Abstract: The installation of one or more prefabricated drains beneath the surface of sediment in a sediment pond utilizing suction or a vacuum to withdraw water from the sediment material to lower the water level down to the level of the prefabricated drains below the pond surface. Dewatering may be coupled with imparting vibrations to the material to further promote both additional dewatering and compaction of the sediment material in the pond. A suitably graded bottom ash, fly ash, sand or large-diameter-solid particle or sediment layer may be added on top of the horizontal drains to enhance dewatering of finer sediment material.

Abstract: The installation of prefabricated drains in a horizontal, generally co-planar pattern below the surface of the CCR with suction or a vacuum to withdraw water from the CCR material to lower the water level down to the level of the prefabricated drains below the CCR surface. Dewatering may be coupled with imparting vibrations to the material to further promote both additional dewatering and compaction of the CCR material in the pond. A suitably graded bottom ash, fly ash, sand or large-diameter-solid particle layer may be added on top of the horizontal drains to enhance dewatering of finer CCR material.

Abstract: A flue gas desulfurization unit is converted from operating with lime or magnesium enhanced lime under inhibited oxidation into a unit that operates using limestone under inhibited oxidation conditions. A ball mill grinding unit may be installed to crush the limestone thereby producing a suspended slurry of fine limestone particles which is pumped to the reaction vessel. When installed, the ball mill may be installed in the process immediately downstream of the existing slaking equipment. The suspended solution may be maintained at a pH in the range of 3.0 to 6.5, optimally at approximately 5.0 to increase the dissolution rate of the limestone reagent produced by the ball mill. The post-conversion process may also require the addition of organic acids and oxidation inhibitors to achieve better SO2 removal from the flue gas.

Abstract: A device for installing horizontal drains in a coal combustion residual or other sludge pond consists of a trenching device that extends downwardly to the depth of required installation of the drains and an attachment through which the drains are fed during installation. The trenching device and attachment are mounted onto a carrier for floatation of the required equipment on the surface of a water-filled sludge pond. The carrier can be winched, hauled or driven across the surface of the sludge. A hydraulic system may be used to raise and lower the trenching device and attachment. The trenching device may be equipped with a chain driven blade mechanism or dredging device for the purpose of cutting a trench into the pond sludge, and a vibratory trenching device may be used to effectively liquefy the material to make the trenching device easier to pull or tow through the sludge in the pond.

Abstract: The installation of prefabricated drains in a horizontal, generally co-planar pattern below the surface of the CCR with suction or a vacuum to withdraw water from the CCR material to lower the water level down to the level of the prefabricated drains below the CCR surface. Dewatering may be coupled with imparting vibrations to the material to further promote both additional dewatering and compaction of the CCR material in the pond. A suitably graded bottom ash, fly ash, sand or large-diameter-solid particle layer may be added on top of the horizontal drains to enhance dewatering of finer CCR material.

Abstract: A process for treating a flue gas desulfurization discharge stream containing dissolved sulfates is presented. Soluble barium compounds, such as barium chloride or barium carbonate are added to the stream in lieu of the traditional two-step lime/carbon dioxide process. The barium compounds cause the sulfate to precipitate as insoluble barium sulfate. The barium sulfate solids settle out of the discharge stream and can be filtered from the process water. The use of soluble barium compounds eliminates the need for subsequent pH adjustment, results in lowering calcium and magnesium concentrations in the discharge stream, and decreases scaling potential in downstream equipment.

Abstract: A flue gas desulfurization unit is converted from operating with lime or magnesium enhanced lime under inhibited oxidation into a unit that operates using limestone under inhibited oxidation conditions. A ball mill grinding unit may be installed to crush the limestone thereby producing a suspended slurry of fine limestone particles which is pumped to the reaction vessel. When installed, the ball mill may be installed in the process immediately downstream of the existing slaking equipment. The suspended solution may be maintained at a pH in the range of 3.0 to 6.5, optimally at approximately 5.0 to increase the dissolution rate of the limestone reagent produced by the ball mill. The post-conversion process may also require the addition of organic acids and oxidation inhibitors to achieve better SO2 removal from the flue gas.

Abstract: When using soda ash reagent in an SBS injection system, various impurities from various possible sources can form suspended solid particles and also form scale that may foul the filtration screens, piping, reagent storage tanks, and instrumentation in the injection system. A system and method are disclosed in which a chelating agent cleaning process removes existing scale, or alternatively, prevents the particles and scale from forming. Various embodiments operate in batch or continuous modes or a combination of both.