“CONTINUOUS METERED INJECTION OF COAL INTO GASIFICATION AND PFBC

SYSTEM OPERATING PRESSURES EXCEEDING 38 Bar (560 PSI)”

Authors:Authors: Derek Aldred, Timothy Saunders Derek Aldred, Timothy Saunders -- Stamet Inc., Stamet Inc.,

International Freiberg Conference on IGCC & International Freiberg Conference on IGCC & XtLXtLTechnologiesTechnologies

June 16-18, 2005

DOE Advanced Gasification Objectives:DOE Advanced Gasification Objectives:

• Expanding Coal-based power production.

• Efficient use of fossil-fuel resources, particularly coal.

• Minimizing emissions.

• Higher operating pressures for improved performance.

• Commercial acceptance.

Gasification Feed Objectives:Gasification Feed Objectives:

• Provide a simple, accurate and reliable feed system.

• Establish controlled, continuous level delivery of coal.

• Minimize gas losses.

• Eliminate high maintenance costs and substantial risks of downtime for existing feed systems.

• Inject at pressures at and beyond 500 PSI (34 Bar).

““FIRTH” Solids PumpFIRTH” Solids Pump

•First Prototype 1978

•Tested the week oil shale program cancelled!

•Concept idle for 10 years

•Stamet Inc., formed to develop concept

Stamet Stamet ““PosimetricPosimetric®”®” Pump TechnologyPump Technology

• Unique concept named for “Positive Metering” of solids.

•One simple continuously rotating element, providing precise flow control.

•Configured machines can deliver solids directly into atmospheric or pressurized environments.

Posimetric Pressure Pump ConfigurationPosimetric Pressure Pump Configuration

First Posimetric First Posimetric Pressure FeederPressure Feeder

•Development Funded by US DOE Clean Coal Program (1994)

•Feeder achieved then record coal injection pressure - over 250 PSI (17 Bar) gas environment

Current DOE Research ProgramCurrent DOE Research Program

• Two year Program schedule Gasifier Visits – define industry needs

– identify typical Coal specificationsSelect Commercial Fuel for Feeder Testing.

• Two-Phased approach:1. Develop semi-scale intermediate pressure feeder2. Develop semi-scale full pressure feeder

Test Feeder Spool AssemblyTest Feeder Spool Assembly

• Shaft

• 2 Discs

• Hub Spacer

• 1 Bearing (of 2)

Test Feeder BodyTest Feeder Body

• Side view showing seal and bearing location

• Body designed for ease of outlet removal and modification

Test Feeder Rig AssemblyTest Feeder Rig Assembly

• Compact for portability

• Tested at multiple locations

• 600 Psi (40 Bar) Vessel pressure rating

Phase 1 Successful Gas Pressure RunPhase 1 Successful Gas Pressure Run

First Run to 300psi

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Torque ft/lb 300psi Achieved24 Bar >

<33900 Nm

Torque

Phase 1 Torque Effect on CoalPhase 1 Torque Effect on Coal

• Compacted Coal Extruded in Feeder Outlet

• High Torque Cause/Effect

• Plug Size 25mm x 50mm x 200mm

Phase 1 Outlet ChangesPhase 1 Outlet Changes

Phase 1 AchievementsPhase 1 Achievements

• Target Feeding into 300psi (20 Bar) Gas Pressure Successfully Achieved

• Optimization Reduced Torque 25%

• Delivery Linear across Full Pressure Range

• High Grip Achieved from Design - Potential for Reduced Machine Size

PhasePhase 2 Objectives2 Objectives

• Develop, test and modify as required a machine for injection of coal into 500 PSI (34 Bar).

• Outline commercial Posimetric® Pump design for coal injection at 500 PSI (34 Bar).

Phase 2 Flow AnalysisPhase 2 Flow Analysis

• Clear disc testing

• Beads used to identify flow regime

• Valuable visualization

of internal flow patterns

Phase 2 Outlet ChangesPhase 2 Outlet Changes

• Revised outlet produced by 3D techniques

• Smoothed transition for flow exiting discs

• Outlet length reduced progressively to determine effect on torque

Phase 2 Success!Phase 2 Success!

Phase 2 FlowPhase 2 Flow--rate Linearityrate Linearity

02-113 DOE Pressure Injection -Test 216. Feeding at 500 psi

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tlet

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< 48 Bar45 Kg >

Phase 2 Gas ConsumptionPhase 2 Gas Consumption

Make-up Gas Consumption vs Outlet Pressure

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Phase 2 Geometry Optimization ResultsPhase 2 Geometry Optimization Results

Outlet Pressure vs Drive Torque Requirements

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Outlet Pressure, psig

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Phase 1 Start

Phase 1 Final

Phase 2

^41 Bar

27000 Nm>

Phase 2 Coal ConditionPhase 2 Coal Condition

• Coal extrusion showing little consolidation.

• “Log” breaks up easily indicating minimal impact from pressure rise.

Phase 2 AchievementsPhase 2 Achievements

• Record pressure level achieved – 560 PSI (38 Bar).

• Very consistent feeder performance.

• Torque reduced 70% over Phase 1.

• Continued linear output against pressure.

• No problems stopping or starting against pressure.

• Coal at outlet little changed from that at inlet.

Phase 2 DeliverablesPhase 2 Deliverables

• Commercial design arrangement finalized.

• Semi-commercial test location identified.

• Off-line site tests anticipated before yearend 2005.

Economic Benefit AnalysisEconomic Benefit Analysis

• Pump Performance data Provided to DOE

• DOE/Parsons Undertaking Benefits Analysis

• Study of Capital and operating cost Savings for Transport and Oxygen Blown (Shell) Gasifiers

• Stamet Pump Eliminates Coal Slurrying/Drying

Plant Capital Cost AnalysisPlant Capital Cost Analysis

Transport Gasifier

Plant Area ($000’s) Design W/Stamet

Coal Prep and Feed 44,473 17,069

Engineering & Contingency 11,118 6,828Auxiliary Power 835 1,988

TOTAL CAPITAL COSTS 56,426 25,885

Balance of Gasifier Island 75,942 75,942

Total Gasifier Island 132,368 101,827

TOTAL GASIFIER ISLAND ($/KW) 437 339

Plant Capital Cost AnalysisPlant Capital Cost Analysis

Shell Gasifier IGCC

Plant Area ($000’s) Design W/Stamet

Coal Prep and Feed 35,670 11,856

Engineering & Contingency 8,918 4,742Auxiliary Power 546 1,300

TOTAL CAPITAL COSTS 45,134 17,898

Balance of Gasifier Island 113,116 113,116

Total Gasifier Island 158,249 131,014

TOTAL GASIFIER ISLAND ($/kW) 611 516

Plant Operating Cost AnalysisPlant Operating Cost Analysis

Transport Gasifier

Plant Output (kWe) Design W/StametGas Turbine Power 197,000 197,000

Steam Turbine Power 140,540 144,000

Auxiliary Load 35,770 39,923

Net Plant Power 301,770 301,077

Net Plant Efficiency (HHV) 40.5% 40.7%

Net Plant Heat Rate (HHV) 8,416 8,386

Plant Operating Cost AnalysisPlant Operating Cost Analysis

Shell Gasifier IGCC

Plant Output (kWe) Design W/StametGas Turbine Power 197,000 197,000

Steam Turbine Power 105,292 107,600

Auxiliary Load 43,150 44,240

Net Plant Power 259,142 260,360

Net Plant Efficiency (HHV) 40.6% 40.9%

Net Plant Heat Rate (HHV) 8,411 8,345

Phase 3 ProgramPhase 3 Program

Expectations:

• 1000 PSI (69 Bar) target for DOE Phase 3.

• Further torque reductions anticipated from

ongoing optimization program.

• Commercial 500 PSI (34 Bar) feeder in 2005.

• 1300 PSI (90 Bar) commercial target requested.

Proposal Submitted – Awaiting Award!