INSTRUMENTS FOR FLUE GAS DESULFURIZATION S p e c i a l A p p l i c a t i o n S e r i e s LEVEL AND FLOW

Flue Gas Desulphurization is widely acknowledged as today’s state-of-the art technology for removing sulfur dioxide from the exhaust flue gas in coal- and oil-fired power plants. In the "wet limestone-gypsum" form of FGD, an aqueous slurry of finely ground limestone is introduced into an absorber tower and contacted with the flue gas. The interaction results in the conversion of SO2 in the gas stream into calcium sulfate, or gypsum, with carbon dioxide (CO2) being routed up the stack. As diagrammed at right, a typical FGD system consists of four units operating simultaneously: (1) Limestone Processing;...

Limestone Store Limestone is delivered either as crushed stone or pre-ground powder. Unground limestone from road or rail hoppers is conveyed to the limestone store for storage. A limestone reclaim machine operates within this vessel. Point Level: Solitel® Vibrating Rod Level Switch for bulk solids. Limestone Bunker Unground limestone is transferred from the limestone store to a bunker prior to its conveyance to the ball mill for grinding. The bunker is a day silo containing a 16- to 24-hour supply. Point Level: Solitel Vibrating Rod Level Switch for bulk solids Pump Protection Process water...

Centrifuge Feed Tank The gypsum slurry is pumped from the absorber to the centrifuge feed tank. Centrifuge operation is initiated by a level controller located in the centrifuge feed tank. Continuous Level: Eclipse or Horizon GWR; or Pulsar Thru-Air Radar Transmitters Centrate Tank The gypsum slurry stream (centrate) produced in the gypsum dewatering operation is routed for residence in a centrate tank prior to its introduction into the limestone slurry feed tank to serve as an additive. Continuous Level: Eclipse or Horizon GWR; Pulsar Thru-Air Radar; Echotel Ultrasound; Kotron® RF Capacitance;...

Water Equalization Tanks Wastewater is held in the equalization tank to allow solids to begin settling and to help maintain a more constant flow rate through the treatment unit. Continuous Level: Eclipse or Horizon GWR; Pulsar Thru-Air Radar; Echotel Ultrasound; Kotron RF Capacitance; or E3 Modulevel Displacer Transmitters Point Level: Echotel Ultrasonic Switch; Kotron RF Capacitance Switch; or Float and Displacer Switches Chemical Storage Tanks An array of chemicals are added from feed tanks to facilitate processing, adjust water quality and chemistry, and inhibit corrosion, scaling, or other...

TO GYPSUM RECOVERY BOILER PRECIPITATOR LIMESTONE SLURRY IN FLUE GAS STREAM TANK SUMPS ACID STORAGE TANK AIR COMPRESSOR REACTION TANK DEMISTER WATER FEED FLUE GAS PURGE TANK TO WATER TREATMENT HYDROCYCLONES UNDERFLOW TANK FEED TANK STACK SO2 Absorption System The SO2-laden boiler flue gas stream passes through the electrostatic precipitators and into the absorber column. Inlet wash water used to prevent a buildup of solids in the inlet duct cools the flue gas as it enters the absorber. The SO2 absorption process begins as the flue gas is scrubbed by the recirculating limestone slurry that also...

Sump Overflow and Leak Detection Small sumps are positioned under tanks plantwide to contain leaks or spills. Sumps also contain leaks from pumps, valves, and pipelines. Point level: Top Mounting Displacer Switch; Echotel Ultrasonic Switch; Float-actuated Flood Level Switch; Thermatel TD1/TD2 Switch with a Spherical Tip; or Kotron RF Capacitance Switch Dibasic Acid (DBA) Storage Tank Organic acid additives improve scrubbing efficiency and reliability, and reduce tower operating cost. DBA is typically stored in a heated, agitated tank from where the acid is fed into a limestone slurry tank or...

Guided Wave Radar Thru-Air Radar Ultrasound RF Capacitance Magnetostriction Thermal Dispersion Float & Displacer Instrumentation from Magnetrol Eclipse and Horizon transmitters are twowire, loop-powered, 24 VDC level transmitters based on Guided Wave Radar (GWR) technology. Available in coaxial, twin rod and single rod probes, these leading-edge transmitters provide measurement performance well beyond that of many traditional technologies. Available with HART®, FOUNDATION fieldbus™ and PROFIBUS® outputs CORPORATE HEADQUARTERS: 5300 Belmont Road • Downers Grove, Illinois 60515-4499 USA • Phone:...