Paradise ScrubbersParadise ScrubbersAll 3 scrubbers are Wet Limestone Flue GasAll 3 scrubbers are Wet Limestone Flue GasDesulfurizationDesulfurizationSystems with Forced OxidationSystems with Forced OxidationUnit 1 and 2 scrubbers are identical and wereUnit 1 and 2 scrubbers are identical and werebuilt in the early 1980built in the early 1980’sUnit 3 scrubber was finished in 2006 and wasUnit 3 scrubber was finished in 2006 and wasbuilt as a result of CAA 1990 regulationsbuilt as a result of CAA 1990 regulationsUnits 1 and 2 produce gypsum/ash slurry, Unit 3Units 1 and 2 produce gypsum/ash slurry, Unit 3produces a gypsum slurryproduces a gypsum slurryAll slurry pumped to gypsum pondAll slurry pumped to gypsum pondParadise ScrubbersParadise ScrubbersUnit 1 and 2Unit 1 and 26venturiventuriabsorbers (VA)absorbers (VA)with 6 recycle tankswith 6 recycle tanksOpen spray towers (3Open spray towers (3levels)levels)Vertical MEVertical ME’sOxidizing air headersOxidizing air headersSide-mounted/Topmounted/Top-mounted agitatorsmounted agitatorsID fans downstreamID fans downstreamRemoves ashRemoves ashRE U1 86%, U2 84%RE U1 86%, U2 84%Unit 3Double contact fountainDouble contact fountainspray (DCFS)spray (DCFS)CocurrentCocurrenttower andtower andcountercurrent tower withcountercurrent tower with1 common tank1 common tankHorizontal MEHorizontal ME’sAir rotaryAir rotaryspargersspargersformixing and oxidationmixing and oxidationBooster fans downstreamBooster fans downstreamof ID fans and upstreamof ID fans and upstreamof moduleof moduleRE 97.6% (98%)RE 97.6% (98%)ScrubberChemistryVenturi AbsorberUnit 1/2 Scrubber Flow DiagramGas Path Through U1/2 ScrubbersNorthGas Path Through U1/2 Scrubbers Looking Toward PowerhouseNorthUnit 3 Scrubber Flow DiagramScrubber OperationScrubber OperationControl pH (U1 and U2: 5.8, U3: 5.8Control pH (U1 and U2: 5.8, U3: 5.8–6.0 depending on6.0 depending oncontrol mode)control mode)Control density(U1 and U2: 7%Control density(U1 and U2: 7%-12% solids, U3: 23%12% solids, U3: 23%solids)solids)Control oxidizing airControl oxidizing airWash mist eliminatorsWash mist eliminatorsMaintain water balanceMaintain water balanceKeep flows up in all slurry piping to avoidKeep flows up in all slurry piping to avoidpluggagepluggageFlush equipment after shutdown to avoidFlush equipment after shutdown to avoidpluggagepluggageMaintain tank levelsMaintain tank levelsOn U1/U2 wash ID fansOn U1/U2 wash ID fansScrubber MaintenanceScrubber MaintenanceCleaningCleaningPacking leaksPacking leaks–pumps,sidemountedsidemountedagitatorsagitatorsPump, Ox air blower and agitator repair and replacementPump, Ox air blower and agitator repair and replacementValve repair/replacementValve repair/replacementPiping repair/replacementPiping repair/replacement–rubber lined and FRPrubber lined and FRPTank and Duct repairTank and Duct repairTank repairTank repairME repairME repairTangential and spray nozzle replacementTangential and spray nozzle replacementInternal slurry and oxidizing air header repairInternal slurry and oxidizing air header repairGear box repair/replacementGear box repair/replacementBall Mill OperationBall Mill OperationControl densityControl densityMaintain water balanceMaintain water balanceKeep flows up in all slurry piping andKeep flows up in all slurry piping andhydrocycloneshydrocyclonesto avoidto avoidpluggagepluggageFlush equipment after shutdown to avoidFlush equipment after shutdown to avoidpluggagepluggageMaintain tank levelsMaintain tank levelsBall Mill MaintenanceBall Mill MaintenanceCleaningCleaningPacking leaksPacking leaks–pumpsPump repair/replacementPump repair/replacementValve rebuild/replacementValve rebuild/replacementPiping repair/replacementPiping repair/replacementAgitator repair/replacementAgitator repair/replacementTank repairTank repairGear box repair/replacementGear box repair/replacementThe EndThe End