Biomass CCS

Dr Amit Bhave

CEO, cmcl innovations

7th IEAGHG International CCS Summer School21st -26th July, University of Nottingham, UK

TESBiC: Techno-economic analysis and road-mapping of biomass to power with

CO2 capture

C-FAST: Carbon-negative hydrocarbon fuels from algal biomass

K2: Coupling of real world data and fast response algorithms

Modelling low carbon technologies

cmcl innovations

Engineering software, technical consulting & training

- automotive, truck & non-road

- clean energy and process engineering

innovation awards

kinetics & srm engine suite: advanced IC engine fuels, combustion and emissions simulator

mod suite: model development suite, data standardisation, uncertainty

propagation, parameter estimation, optimisation

Contents

• Biomass CCS: scope and context

• Impetus for biomass CCS

• Bioenergy strategy and biomass supply chain

• Biomass CCS technology combinations

• A case study

• Summary

biomass CCS: scope

Source: EBTP and ZEP joint report on BioCCS, 2012

Biomass fuelled power generation with CCS for heat and/or power

Impetus for biomass CCS

• ETI’s ESME toolkit’s least-cost options for meeting the UK’s energy demand and emissions reduction targets to 2050, identify biomass CCS as vital with large, negativeemissions, a high option value and high persistence

• IEAGHG, 2011: Despite its strong GHG reduction potential, there is a considerable dearth of information for biomass CCS as compared to that for fossil based CCS

• APGTF, 2011/2012: RD&D strategic themes and priorities - whole system : focus on virtual system simulation and optimisation- capture technologies: focus on economics, efficiency penalty, emissions,

co-fired biomass, 2nd and 3rd generation technologies

• EBTP/Zep 2012: Accelerate deployment of advanced biomass conversion processes and establish an EU biomass CCS roadmap towards 2050.

• TESBiC 2011/2012: Significant gaps that exist in the understanding of biomass CCS -key technical and economic barriers, and UK deployment potential to 2050

Bioenergy strategy

• Renewable Energy Strategy (RES) 15% renewable energy by 2020

• Sustainable biomass could contribute 8%-11% of the total UK energy demand by 2020

• International supplies (USA/Canada for example) will be the key contributors

• Current use of biomass in EU27 and projections for 2020, 2030 up to 2050 reveal a four-fold increase to ~370 Mtoe.

Biomass CCS: a system-level approach

Biomass supply chain

Biomass pre-processing Biomass thermo-chemical conversion to power

and CO2 capture

CO2 transport and storage

Biomass supply chain

Important characteristics of the biomass supply chain :

• Cost/availability of local vs. imported biomass

• Location of local biomass sources w.r.t. CO2 network

• Quality of biomass: low sulfur content, but chloride and potassium salts and ash chemistry (rather than the ash content)

Types of biomass:

• Forestry biomass

• Agricultural residues

• Energy crops

• Municipal solid waste

• Industrial waste

Biomass supply chain structure:

• In-field/in-forest collection/harvesting

• In-field/in-forest handling and transport

• Loading to/unloading from transportation

• Transportation

• Storage

• Pre-processing

Biomass sustainability criteria

• UK government’s Sustainability Criteria require an independently verified minimum 60% GHG savings (vs. EU fossil grid average) across the whole biomass supply chain

• If criteria not met, biomass generators will not receive government support necessary to make businesses economically viable

• Sustainability challenges:

– Ensuring significant reductions (vs. fossils) in CO2 emissions

– No negative impact on forest productivity, biodiversity and cover, indigenous populations, etc.

– Avoiding illegal logging

Biomass sustainability measures

For example, Drax, UK’s largest coal power station (4000 MW capacity) in its transformation to a predominantly biomass-fuelled power generator has incorporated a comprehensive “sustainable biomass procurement programme”

• Rejection of all non-sustainable biomass

• All supply chain stages are investigated - cultivation and harvesting, transforming, processing and transportation.

• Minimum standards on life cycle GHG savings

• Compliance with policy written in to contracts

• Extensive data gathering and assessment through a programme of information exchange and an improvement programme

• Independent 3rd party audit

Biomass feedstock pre-processing

• Coal vs. biomass at plant-site: – Dust management: risk of fire, explosion, etc.– Volume: Lower energy density, distribution– Storage: dry storage and self-heating minimisation

• Wood chips (1-5 cm long), moisture content high, stored for a limited time, less energy to produce

• Pellets made from chips, particle size < 2mm, more energy to produce than chips

• But higher energy density with pellets, do not degrade (rot) so easily, preferred for transport over large distances

• Torrefaction: – Biomass: Moulds/rot during storage, heterogeneity/particle size reduction– Mild pyrolysis. Range: 230-290oC. Mass loss up to 30%. Retained energy

content 90%. – Behaves more like coal good feedstock for transition from fossils to biomass– Exothermic nature requires good temperature control– Powdered torrified biomass – high reactivity– Torrefied pelletization requires additive binder– Unknowns: Scale-up and CAPEX, OPEX implications (LCA)

Biomass feedstock: pellets[50 pence coin added for scale]

Biomass conversion to power

Coal technologies

• Pulverised coal combustion:

• Direct co-firing of biomass

• Conversion to 100% biomass

• Integrated gasification combined cycle (IGCC) coal gasification:

• Direct co-firing of biomass

• Conversion to 100% biomass

Biomass technologies

• Dedicated biomass combustion:

• Bubbling fluidised bed

• Circulating fluidised bed

• Fixed grate

• Dedicated biomass gasification:

• Bubbling fluidised bed

• Circulating fluidised bed

• Dual fluidised bed

• Entrained flow

Biomass firing capacity pathways:• Co-firing: cheapest way to get new biomass firing capacity, • Other options such less cost-effective options involve converting existing coal fired plants to operate dedicated biomass, or a new build plant

CO2 capture techniques

Post-combustion

• Solvent scrubbing, e.g. amines, chilled ammonia

• Low-temperature solid sorbents, e.g. supported amines

• Ionic liquids

• Enzymes

• Membrane separation of CO2 from flue gas

• High-temperature solid sorbents, e.g. carbonate looping

Pre-combustion

• IGCC with physical solvent absorption

• Membrane syngas generation, with physical solvent absorption

• Membrane separation of H2 from syngas

• Sorbent enhanced reforming using carbonate looping

• ZECA concept

Oxy-combustion

• Oxy-fuel boiler with cryogenic O2separation from air

• Oxy-fuel boiler with membrane O2separation from air

• Chemical-looping-combustion using solid oxygen carriers

TRLs: CCS technologies

1 2 3 4 5 6 7 8 9

Solvent scrubbing

Low-temp solid sorbents

Ionic liquids

Enzymes

CO2 membrane separation

Carbonate looping

Oxy-fuel with cryogenic O2

Oxy-fuel with membrane O2

Chemical-looping-combustion

IGCC with solvent absorption

H2 membrane separation

Syngas membrane

Sorbent enhanced reforming

ZECA concept

TRL

Co-firing

Dedicated

TRL = Technology Readiness LevelTRL 1 = Basic researchTRL 2 = Theoretical researchTRL 3 = Applied researchTRL 4 = Bench-scale test rigTRL 5 = Pilot plantTRL 6 = Small-scale demonstration plantTRL 7 = Full-scale demonstration plantTRL 8 = First commercial plants TRL 9 = Mass deployment of fully commercial plants

Biomass CCS roadmap: assessment criteria

Development aspects and prospects

• Key drivers for development

• Key development issues, potential show-stoppers

• Main players internationally

• Pilot/demonstration /commercial plants and R&D activities

• Current TRL

• Likely TRL in 2020

• Environmental issues

Feedstocks and feasibility

• Contaminants of risk, required specifications

• Pre-processing needs, benefits

• Appropriate feedstocks, robustness to variability

• Maximum % co-firing feasible

• Technical feasibility of component combination

• Ease of changing to high co-firing / 100% dedicated conversion

Techno-economics

• Equipment scales (MW min, MW max), suitability for small-scale

• Plant LHV efficiency with capture

• Flexibility, ability to load follow

• Capital cost with capture

Technology combinations

Solvent

scrubbing,

e.g. MEA,

chilled

ammonia

Low-temp

solid

sorbents,

e.g.

supported

amines

Ionic

liquidsEnzymes

Membrane

separation

of CO2 from

flue gas

High-temp

solid

sorbents,

e.g.

carbonate

looping

Oxy-fuel

boiler with

cryogenic O2

separation

Oxy-fuel

boiler with

membrane

O2

separation

Chemical-

looping-

combustion

using solid

oxygen

carriers

IGCC with

physical

absorption

e.g.

Rectisol,

Selexol

Membrane

separation

of H2 from

synthesis

gases

Membrane

production

of syngas

Sorbent

enhanced

reforming

using

carbonate

looping

ZECA

concept

Direct cofiring

Conversion to 100% biomass

Direct cofiring

Conversion to 100% biomass

Fixed grate

Bubbling fluidised bed

Circulating fluidised bed

Bubbling fluidised bed

Circulating fluidised bed

Dual fluidised bed

Entrained flow

22 24

12

14

9 11 13

Not feasible

18 20

11a

12a

Not feasible

Dedicated

biomass

gasification

Not feasible 16

Dedicated

biomass

combustion

2 4 6 8 106a

Post-combustion Oxy-combustion Pre-combustion

Coal IGCC

gasificationNot feasible Not feasible 15 17 19 21 23

Pulverised coal

combustion1 3 5 75a

Short-listed biomass CCS technologies

Criteria

Co-firing amine

scrubbing

Dedicated biomass with

amine scrubbing

Co-firing oxy-fuel

Dedicated biomass oxy-fuel

Co-firing carbonate looping

Dedicated biomass chemical looping

Co-firing IGCC

Dedicated biomass BIGCC

Likely TRL in

2020

7 to 8 6 to 7 7 6 5 to 6 5 to 6 7 5 to 6

Key technical

issues

Scale-up, amine

degradation,

Scale-up, amine

degradation,

O2 energy costs, slow response

O2 energy costs, slow

response

Calciner firing, solid degradation, large purge of CaO

Loss in activity, reaction

rates, dual bed

operation

Complex operation,

slow response, tar

cleaning, retrofit

impractical

Complex operation,

slow response, tar

cleaning, retrofit

impractical

Suitability for

small scale

Low High Low High Low High Low High

Plant

efficiency

with capture

OK Low OK Low Good Good High, Good

Capital costs

with capture

OK Expensive OK High ASU costs

OK OK OK Expensive,

UK

deployment

potential

Immediate capture retrofit

opportunities,

retrofit opportunities

high long-term

potential

retrofit opportunities

, long-term doubtful

retrofit opportunities

, high long-term

potential

capture retrofit opportunities,

cement integration

Likely first demos in

Europe, UK in ~2020. High long term potential

No current UK plants,

several demos by

2020Long-term

doubt

No current UK plants,

demo unlikely by

2020.High long-

term potential

Techno-economics: a case study

Biomass chemical looping

Biomass chemical looping: costing

Variable Costs Usage £M/yr

1. Wood fuel 8.29 108 kg/yr 116.0

2. Oxygen carrier (new) 1.19 106 kg/yr 4.74

3. Spent carrier (credit) -4.22

4. Fly ash disposal 1.78 106 kg/yr 0.00356

5. Cooling water make-up 9588 kg/s 51.4

Variable costs 167.9

Maintenance and Labour 20.37

Insurance 5.09

Fixed costs 25.46

Total O&M costs 193.36

Capacities investigated: 40 to 300 MWe

Item £M, 2011

Storage and handling of solid materials 41.1

Boiler island 220.5

CO2 compression and drying plant 31.4

Power island 76.5

Air reactor (458 m3) 64.8

Fuel reactor (581 m3) 74.9

Total installed CAPEX 509.2

Operation and utilities (% of TIC) 25.5

Civils and land costs (% of TIC) 50.9

Project Development Costs (% of TIC) 25.5

Contingency (% of TIC) 50.9

Total investment cost 661.9

Specific investment cost (£M/MWe) 2.21

268 MWe, net LHV efficiency ~ 38.7%

Model formulation: CAPEX, OPEX, generation efficiency, and emissions as a function of the nameplate capacities and extent of CO2 capture.

Biomass CCS: techno-economic comparison

TRL

Summary - 1

• To date, little activity at industrial scale on the application of CO2 capture technologies to co-fired or dedicated biomass power plants. This dearth of practical data increases the complexity and uncertainties associated with the estimation and roadmapping of biomass CCS technologies.

• The industry’s progression to the large fossil-based CCS demonstration projects is slow due to high costs and requirement of significant government subsidies.

• Dependency on fossil based CCS: Recent setbacks and cancellations of the coal-based CCS projects will further delay the development of biomass CCS. This, however, also presents an opportunity for lower TRL biomass CCS technologies.

• Incentivising negative CO2 emissions via the capture and storage of biogenic CO2 under the EU emissions trading scheme (ETS) is highly important.

Summary - 2

• Biomass CCS attractive for small (50 MWe), intermediate (250 MWe) and large (~600 MWe) scales. At large scales, the issue of “sustainable biomass procurement” also needs careful consideration.

• For the eight biomass-based power generation combined with carbon capture technologies varying over a wide range of TRLs, from TRL 3 to TRL 8, the range of techno-economic parameters are the following:

• ~ 5% to 15% : Range of the efficiency drop

• ~ 45% to 130%: Range of the increase in specific CAPEX (£/MWe) with CO2 capture

• ~ 4% to 36%: Range of increase in OPEX (£/yr) with carbon capture

• CAPEX, LCOE: Generation scales and fuel costs the main drivers