investing in r&d pathway to low-carbon lignite...
TRANSCRIPT
Investing in R&D
Pathway to Low-Carbon Lignite Utilization
Mike Holmes
Director of Energy Systems Development
PRESENTATION OUTLINE
• Investment in R&D
– Industry Pathway
– Carbon Management
– Next-Generation Lignite Fired Power
PIONEERS AND SYNERGIES
TRENDS
www3.epa.gov/airtrends/aqtrends.html
www.eia.gov/totalenergy/data/monthly/#electricity
CO, O3, Pb, NO2, PM, SO2
CARBON MANAGEMENT
5
• Carbon Utilization and Storage / EOR
• CO2 Capture Technology Development
• Development of Next Generation Power Systems
Oil Fields
6000+ fields evaluated.
Fields in the Williston, Powder River,
Denver–Julesberg, and Alberta Basins
were evaluated.
Used two methods:
enhanced oil recovery (EOR) and volumetric
• EOR approach:
Evaluated ~160 fields.
Sequestration capacity
= 1 billion tons
Incremental oil
>3 billion bbl
• Volumetric approach:
Thousands of fields, total
capacity >10 billion tons.
BAKKEN CO2 DEMAND FOR NORTH DAKOTA –
A 30,000-FT VIEW
Based on the following:
• Traditional evaluation techniques
• North Dakota Industrial Commission (NDIC)
original-oil-in-place (OOIP) estimates
• 4% incremental recovery
• Net utilization of 5000 and 8000 ft3/bbl
2–3.2 Bt of CO2 needed, yielding 4–7 Bbbl of oil.
North Dakota currently produces ~33 Mtpy of CO2.
Bakken growth is creating a projected increase in
power demand.
PATHWAY TO LOW-CARBON LIGNITE UTILIZATION
PROJECT TEAM AND INDUSTRY CONTACTS
• State of North Dakota – Mike Jones, LEC/LRC
• ALLETE (MP and BNI) – Bill Sawyer
• Basin Electric (Basin and DGC) – Jim Sheldon
• 8 Rivers Capital – Mike McGroddy
• EERC – Jason Laumb
9
PATHWAY TO
LOW-CARBON
LIGNITE
UTILIZATION
WHAT IS THE ALLAM CYCLE?
The Allam Cycle is a supercritical CO₂ Brayton cycle:
– Oxy-fueled and direct-fired.
– Recuperates turbine exhaust heat via a recycle stream.
– Can utilize a heat sources in addition to the turbine exhaust.
– Turbine inlet temperature above 800°C (1000°‒1200°C optimal)
– Turbine inlet pressure above 80 bar (200‒400 bar optimal).
– Exhaust is CO2 with moderate impurities.
Contains the intellectual property of 8 Rivers Capital, LLC and NET Power, LLC
Natural Gas Allam Cycle 58.9% Efficiency LHV
ALLAM CYCLE PROCESS DIAGRAM
9
Core Allam Cycle
Natural Gas
Process
• High efficiency with
existing gasifier
technologies
• Minimal gasifier
integration required,
low complexity
• Process simplification
significantly reduces
cost vs. IGCC
• Zero emissions. No
additional capture or
compression
equipment needed
Efficiency LHV HHV
Gross Turbine Output 76.3% 72.5%Coal prep & feed -0.2% -0.2%
ASU -10.2% -9.7%CO2, Syngas Comp. -9.1% -8.7%Other Auxiliaries -6.5% -6.1%
Net Efficiency 50.3% 47.8%
• The Allam Cycle can be used with both natural gas and
solid fuels while maintaining full carbon capture.
• Use with solid fuels requires the addition of a coal gasifierExisting, mature,
proven
technology
13
PHASE 1A TECHNICAL CHALLENGE AREAS
Gasifier Selection 2
Combustor Modeling4
1
3
Corrosion
Impurities Removal
14
Task 1 - CORROSION MANAGEMENT
• Undertaking two stages to the study:
– Under Phase 1A: Static coupon testing at the EERC.
– Under Phase 1B: Dynamic testing at a selected facility.
• The results of Phase 1A will enable high-level design decisions.
15
LOW-TEMPERATURE ALLOYS
• Alloy 20 – 34% Ni, 20Cr, 4Cu, 3Mo, balance Fe, resists
pitting, acid corrosion, and stress corrosion cracking.
• AL-6XN – 24% Ni, 21Cr, 7Mo, balance Fe, super austenitic,
stronger than stainless, resists corrosion and stress
corrosion cracking.
• 347 Stainless – 11% Ni, 18Cr, 1(Nb+Ta), balance Fe
• 321 Stainless – 11% Ni, 18Cr, 0.75Cu, 0.75Mo, 0.7Ti,
balance Fe.
• 316L Stainless – 12%Ni, 17Cr, 3Mo, balance Fe.
• 304L Stainless – 9% Ni, 19Cr, balance Fe.
Decreasing
Nickel
Increasing Cost
3.91
3.42
1.21
1.10
1.29
1.00
Relative
Cost
Factor
ADVANCING THE PROJECT, CORROSION
• Results to date indicate that exotic alloys are not needed in areas exposed to liquid
pH as low as 3.
• Impurity removal testing has highlighted the possibility of selective condensation of
acids.
– The final test will aid in determining the resistance of these alloys to this type of
attack.
• Result of the work will be projections of material corrosion rates to be used during
Phase 2a discussions with vendors: a basis to determine materials of construction
and design specifications for system components.
• No major barriers.
16
17
TASK 2 –GASIFIER SELECTION
• Gasifier selection will impact all areas
of the Allam Cycle.
• Lignite fuel spec developed.
• The team is currently developing
process models for selected
technologies.
• The goal is to have identified two to five
technologies for further consideration in
Phase 1b.
18
DETAILS OF SELECTED SYSTEMS
• The team is progressing on further downselection of gasification systems based on additional criteria:
– Costs
– Commercial guarantees
– Sodium impacts
– Overall system efficiency
Gasifier Name Vendor
Vendor
Headquarters System Type Feed Ash
Original
Rank
Lurgi Air Liquide Germany Fixed bed Dry Nonslagging 1
BGL Envirotherm Germany Fixed bed Dry Slagging 2
SE ECUST/Sinopec China Entrained flow Dry Slagging 3
TRIG KBR/Southern Company USA Fluid bed Dry Nonslagging 4
HTW ThyssenKrupp Uhde Germany Fluid bed Dry Nonslagging 5
U-GAS SES USA Fluid bed Dry Agglomerated 6
SFG Siemens Germany Entrained flow Dry Slagging 7
SCGP Shell Netherlands Entrained flow Dry Slagging 8
Prenflo ThyssenKrupp Uhde Germany Entrained flow Dry Slagging 9
TASK 3 – IMPURITY MANAGEMENT
• The Allam Cycle lends itself to cost-effective
postcombustion removal of impurities; however, this
requires that the turbine and heat exchanger have high
resistance to corrosive materials.
• Precombustion technologies are commercially available.
• The team will review options for both technical fit in the
process and commercial readiness.
20
TASK 3 – IMPURITY MANAGEMENT
• Three test campaigns completed.
– Two under oxy-combustion conditions.
– One under a two-stage concept with
gasifier and syngas combustor.
• DeSNOx process tested as
postcombustion removal.
21
22
AREA 3: IMPURITIES REMOVAL
• High SOx and NOx removals
– SOx: >99% removal
– NOx ~95% removal
23
ADVANCING THE PROJECT, IMPURITY MANAGEMENT
• The DeSNOx process provides a high degree of acid gas capture.
• The pH of solutions in the process must be controlled to prevent selective acid
condensation.
– Specialty metals
– Corrosion task
• Sulfur can be removed with oxygen if NOx is not present.
– 60% removal at 1% oxygen, >90% removal at 3% oxygen
• Water management will be critical for DeSNOx
– pH <1 without water additions
• Precombustion removal tested in the next phase.
• No major barriers.
TASK 4 –SYNGAS COMBUSTOR DESIGN
• Development of the syngas combustor variant is a critical item for the coal-based Allam Cycle.
• DOE program (~$1M) at 8 Rivers Capital has completed initial phase to develop initial specifications for pilot-scale test article:
– Now undertaking selection of partner to support subsequent testing phase.
– EERC evaluating capabilities to support both design and testing phases of the program.
• Gasifier selection and syngas stability study are key inputs needed from the current work.
24
26
ADVANCING THE PROJECT, SYNGAS COMBUSTOR
DESIGN
– 2-D and 3-D CFD models indicate good mixing of fuel and oxidizer. Negligible
pressure oscillations.
– Four fuel compositions were simulated to verify capability for burning a range of
fuels.
– CFD shows that excess O2 leads to low levels of CO in the exhaust but increases
O2 content.
– Full mechanical test of combustor design was conducted to verify structural
integrity and instrumentation of the test rig.
– Test rig and program design completed.
TASK 4 –STATUS UPDATE
• Several viable test sites identified and vetted, with preliminary costing
and rig design completed for each
– NASA White Sands and DGC are leading candidates
• NET Power demo is also a possible site (time line issues)
• Team is talking with EPRI regarding support
• First step funded with University of Central Florida (~$60K)
• 8RC applying for SBIR (~$150K) to avoid delay in progress
27
28
BUYING DOWN THE OVERALL PROGRAM RISK
• Materials exist that can survive in low-temperature areas.
– Dynamic and high-temperature tests forthcoming
• Gasification platforms exist that will gasify lignite.
– Which is best for the Allam Cycle?
– Consider polygen?
• Post-combustion sulfur removal technology shows great promise:
– pH dependent
– Water addition crucial
– Technologies do exist – energy penalty
– Precombustion testing coming
• Syngas combustor evaluation
– Design for syngas
– Demonstration on natural gas
SUMMARY
• World coal use is growing, while U.S. coal use is losing ground because of regulations, low natural gas prices, policy uncertainties …
• Technology advancements are needed to both meet compliance goals and maintain the current cost of electricity (COE).
• CO2 EOR can be a large factor in economics to help drive carbon capture, utilization, and storage (CCUS) applications.
• Supercritical CO2 cycles offer great potential for next-generation power.
– High efficiency, low COE, simplified CCUS …
– Barriers need to be addressed.
– Accelerated schedules needed.
• Leadership, teamwork, taking advantage of synergies will be key to the future of coal.
28
POLYGENERATION
EERC Working on Front-End Engineering and Design (FEED) and Regional, Economic, and Political Factors
Polygen considerations
• Direct or indirect liquefaction
• Gas separation for CO2 and H2 production
• Syngas to liquid fuels, chemicals, fertilizer, and other
products
Electricity considerations
• Supercritical combustion or high-efficiency advanced
integrated gasification combined cycle (IGCC)
• CO2 capture for EOR
THANK YOU!
CONTACT INFORMATION
Energy & Environmental Research Center
University of North Dakota
15 North 23rd Street, Stop 9018
Grand Forks, ND 58202-9018
www.undeerc.org
701.777.5000 (phone)
701.777.5181 (fax)
Mike Holmes
Director of Energy Systems Development
701.777.5267