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����Chemistry in Gas Turbine Power PlantsTopics

Gas Turbine Operating Media:� Gas Turbine Fuels (Oil, Gas)� Air� Water

Systems:� Hot Gas Path� Air Path� Cooling Systems

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����Chemistry in Gas Turbine Power PlantsProcess Diagram

Hot Gas PathCorrosion & Fouling

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����Chemistry in Gas Turbine Power PlantsImpurities in Fuel: Trace Metals & Salts

Hot corrosion(sulphidation) causedby excessive alkalimetal content in fuel.

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����Chemistry in Gas Turbine Power PlantsFuel Additive Dosing

Mg additive is dosed into heavy fuel oil against corrosion attackby vanadium oxide melts:

Switch to low sulphurfuel resulted in non-washable Mg oxidedeposits.

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����Chemistry in Gas Turbine Power PlantsImpurities in Fuel: Corrosion Products

Deposits of molteniron oxides from fuelgas on GT blading.

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����Chemistry in Gas Turbine Power PlantsProcess Diagram

Air Intake FilterFouling

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����Chemistry in Gas Turbine Power PlantsGT Air Intake Filter I

Overloadedcoalescer filter

Salts and dust fromprefilter

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����Chemistry in Gas Turbine Power PlantsGT Air Intake Filter II

Water on floor betweenprefilter and fine filter

Salts on floor after fine filter

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����Chemistry in Gas Turbine Power PlantsProcess Diagram

Inlet Air Cooling

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����Chemistry in Gas Turbine Power PlantsEvaporative Cooling

Evaporative cooling cells

Deposits in in evaporativecooling sump.

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����Chemistry in Gas Turbine Power PlantsAir Inlet Fogging

Fogginng inoperation

Fouling of nozzle filter

Fogging Rackwith nozzles

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����Chemistry in Gas Turbine Power PlantsProcess Diagram

GT Compressor Corrosion & Fouling

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����Chemistry in Gas Turbine Power PlantsGT Compressor Erosion & Fouling

Erosion of compressorblade leading edge bydust and water droplets

Salt deposits Soot and tar-like deposits

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����Chemistry in Gas Turbine Power PlantsGT Compressor Corrosion

Standstillcorrosion ofcompressor

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����Chemistry in Gas Turbine Power PlantsProcess Diagram

Cooling Channel Blocking

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����Chemistry in Gas Turbine Power PlantsGT Cooling Channel Blocking

Blocking ofcoolingchannels

Exfoliatedscale

Salts &rust

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����Chemistry in Gas Turbine Power PlantsSummary

� In order to guarantee the perfomance andcomponent‘s lifetime in gas turbine power plants theimpurity levels in all operating media have to becontrolled.

� Fot the achievement of this goal suitable measureshave to be taken during desing and operation.

� If the boundary conditions (fuel compostion, ambientair conditions, water purity) change their impact onthe gas turbine operation has to be evaluated.