2008.03.11
CATO board meeting
Integrated Surface Mineralisation
Process
Mineralisation
Contents
• Mineralisation in CATO
• Integrated surface mineralisation process
• Perspectives for surface mineralisation
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Mineralisation
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Mineralisation - characteristics
• Geochemical weathering of olivine rock:
2 CO2 (g) + Mg2SiO4(s) → 2 MgCO3 (s) + SiO2 (s)
• Very slow process (geological time scale):
- lack of surface area
- low CO2 concentration in atmosphere
• Exothermic reaction:
∆H= -134 kJ/mole Mg2SiO4
• Capacity approximately
0.625 ton CO2 / ton rock
• Abundant raw material
Stable end products
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Mineralisation
WP4: Mineralisation
Prof. Chris Spiers, Geowetenschappen Univ.Utrecht
Mineralisation: CO2 trapping by reaction with rock
→ stable minerals or solutions
WP4.1: Subsurface Mineralisation (Shell, U-Utrecht)
accompanies geological storage
WP4.2: Surface Mineralisation (TNO, ECN, Geochem)
= industrial process
WP4+: Accelerated weathering of olivine (Schuiling)
= crushed olivine → beaches / land
Geochem Research BV
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Mineralisation
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WP4.2: Surface Mineralisation
• ECN (TU Delft)
- use of industrial minerals (slags) for CCS
- thesis Wouter Huijgen
• Geochem Research
- process for acidic digestion with acid recycle
- alternative to MgO production from MgCO3 kilns
• TNO
- process with for acidic digestion (nitric acid)
- followed by precipitation with base (ammonia)
- integrated with production fertilizer
Geochem Research BV
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Mineralisation
TNO integrated process for mineralization
• Dissolution of olivine rock with nitric acid:
4 HNO3 (aq) + Mg2SiO4(s) → 2 Mg(NO3)2 (aq) + SiO2 (s) + 2 H2O (l)
• Precipitation of magnesium hydroxide with ammonia:
Mg(NO3)2 (aq) + 2 NH4OH (aq) → 2 NH4NO3 (aq) + Mg(OH)2 (s)
• Capture of carbon dioxide with magnesium hydroxide:
CO2 (g) + Mg(OH)2 (s) → MgCO3 (s) + H2O (l)
• Overall mineralisation reaction for CO2 capture and storage :
2 CO2 (g) + Mg2SiO4(s) + 4 HNO3 (aq) + 4 NH3 (g) →
2 MgCO3 (s) + SiO2 (s) + 4 NH4NO3 (aq)
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Mineralisation
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Conventional NH4NO3 process
HNO3 (aq)
NH3 (g)
NH4NO3 (aq)
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Mineralisation
Modified NH4NO3 process for Mg(OH)2 co-production
Mg2SiO4 (s)
NH3 (g)
HNO3 (aq)
T=80°C
SiO2 (s)
Mg (NO3)2 (aq)
T=80°C
pH=8
Mg(OH)2 (s)
NH4NO3 (aq)
TNO patent WO 2007/055570
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Mineralisation
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Modified NH4NO3 process for direct CO2 sequestration
Mg2SiO4 (s)
HNO3 (aq)
NH3 (g)
T=40-80°C
pH=7-8
MgCO3 (s)
T=80°C
SiO2 (s)
CO2 (g)
Mg (NO3)2 (aq)
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NH4NO3 (aq)
Mineralisation
Post combustion capture Amine solvent recovery
• Capture of CO2 with amine solvent:
RNH2 (aq) + CO2 (g) → RNH3+ (aq) + HCO3- (aq)
• Regeneration of the amine with magnesium hydroxide:
RNH3+ (aq) + HCO3- (aq) + Mg(OH)2 (s) →
RNH2 (aq) + MgCO3 (s) + 2 H2O (l)
• Source needed for magnesium hydroxide: olivine rock
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Mineralisation
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Modified NH4NO3 process CO2 sequestration with amine-solvent regeneration
Mg2SiO4 (s)
HNO3 (aq)
NH3 (g)
T=80°C
T=40°C
pH=8
MgCO3 (s)
T=80°C
pH=8
SiO2 (s)
Mg (NO3)2 (aq)
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RNH3+HCO3- (aq)
Mg(OH)2 (s)
RNH2 (aq)
NH4NO3 (aq)
Mineralisation
Process Flow Sheet
Flowsheet versie 1.01
Auteur: R.J.M. Bisselink
Datum: 17 november 2006
Olivijn (03 wt% als Fe)
6.0E+05 t.year-1
HNO3 (57%)
-1
2.3E+06 t.year
-1
3.5E+05 t.year
CO2
8.2E+04 t.year-1
NH3
2.8E+05 t.year-1
NH3
-1
6.8E+05 t.year
MgCO3
-1
4.7E+05 t.year
Mg(OH)2
Q
pH ~ 4
Q
-1
1.7E+06
3.6E+04 t.year
NH3
pH ~ 7
NH4NO3
(22% N)
-1
2.7E+06 t.year
2.5E+05 t.year
SiO2
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-1
2.1E+04 t.year
FeO
-1
Mineralisation
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CO2 sequestration potential
Emission
Syngas + NH3 production
process emission
combustion
total
total
Sequestration
CH4
coal
1.29
0.5
1.79
2.07
0.8
2.87
[ton CO2/ton NH3]
[ton CO2/ton NH3]
[ton CO2/ton NH3]
0.38
0.61
[ton CO2/ton NH4NO3]
0.22
0.22
[ton CO2/ton NH4NO3]
Capacity: worldwide 30-40 Mtpa CO2 (5 Magnums)
based on worldwide 120 Mtpa NH4NO3
*Emission mineralisation process not included
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Mineralisation
Process economics
• Two scenarios:
a. stand-alone (sea port / NH3 terminal) with local HNO3production
b. integrated with fertilizer plant – fee for use HNO3 and NH3
• Sensitive to cost/revenue raw materials/products
- logistics / solids handling
- large scale application for MgCO3 and SiO2 required
- carbon credits optional for economic feasibility
• Better estimates required for:
- CAPEX: investment costs, equipment sizing
- OPEX: transport, materials handling, heat integration
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Mineralisation
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Summary integrated surface mineralisation process
Match with fertilizer industries
• Production of NH4NO3 directly coupled with CO2-production
• Part of CO2 is sold as product or as ureum H2NCONH2
• Proposed is a modified process for production of NH4NO3
with simultaneous CO2 capture
Advantages
• Enables increased production without higher CO2 emission
• Or use of cheaper feedstock (coal, heavy oil) with larger CO2
emission compare to methane
• Applicable by-products SiO2, MgCO3, FeO, Ni(OH)2
Opportunity
• Application of MgCO3 in product formulation
• Replacement of crushed/ground Dolomite
• Reactivity carbonate minerals issue
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Mineralisation
Outlook surface mineralisation
Integrated surface mineralisation process:
• Niche application fertilizer industry
- potential 30-40 Mtpa CO2 but not Gtpa
- carbonates potentially applicable in product formulation
• Challenges:
- proof-of-concept
- geographic and logistic constraints
- integration with fertilizer plant
- market for solid products, Mg products
- technical/economic evaluation
Perspectives surface mineralisation:
• Direct mineralisation process
• Enhanced chemical weathering
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Mineralisation
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Direct CO2 sequestration
2 CO2 (g) + Mg2SiO4(s) → 2 MgCO3 (s) + SiO2 (s)
Mg2SiO4 (s)
salt (aq)
T=185°C
Pco2=115 bar
SiO2 (s)
MgCO3 (s)
[O’Connor ]
•
•
•
•
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Salt solution accelerated
Time scale ~minutes
Integrated with gasification
Mixed by-products
CO2 (g)
salt (aq)
Mineralisation
Accelerated weathering of olivine (Schuiling)
Concept: mine → crush/grind → transport → weather
Assumes: 4CO2 (g) + Mg2SiO4(s) + 2H2O → 2 Mg2+ + 4HCO3− + SiO2 (s)
- CO2 trapped in dissolved bicarbonate
- 1.25 ton CO2 / ton Olivine !!!!
Coastal distribution - Reaction slow (UU:50% in 250 yrs)
Tropical weathering - more promising (hot, acid)
Unclear:
Reaction OK? CO2 remain fixed?
Environmental impact?
Costs, practicality of transport ?
Geochem Research BV
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Mineralisation
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Thank you for your attention.
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Mineralisation
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