Negative Emissions Technologies and Reliable Sequestration A Research Agenda (2019) / Chapter Skim
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6 Carbon Mineralization of CO2
6 Carbon Mineralization of CO2
Pages 247-318
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From page 247... ...
Because they utilize this naturally available chemical energy, these methods may offer a low cost means to mitigate greenhouse gas emissions. And because the CO2 is locked into solid carbonate minerals, storage has a strong potential to be permanent and nontoxic.
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From page 248... ...
or both removing CO2 from air and storing it in carbonate minerals (referred to as combined mineral capture and storage)
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From page 249... ...
surficial carbon mineralization -- CO2-bearing fluid or gas is reacted with mine tailings, alkaline industrial wastes, or sedimentary formations rich in reactive rock fragments, all with a high proportion of reactive surface area, and 3. in situ carbon mineralization -- CO2-bearing fluids are circulated through suit able rock formations at depth.
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From page 250... ...
In situ carbon mineralization CO2 storage in basaltic rocks has been studied in two medium-scale experiments and warrants further exploration at the scale of Mt/y CO2. Natural examples of extensive in situ mineral capture and storage in ultramafic rocks, rapid reaction rates in laboratory studies, and the potential for permanent storage of hundreds of trillions of tons of CO2 warrant continued basic research into this little-studied, high-risk, high-reward opportunity.
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From page 251... ...
When fully carbonated, a ton of wollastonite can store 0.33 tons of CO2, so these costs correspond to $600-1,000/tCO2. Even if these are the only costs of CO2 storage using wollastonite, these costs are more than 10 times higher than the cost of storing CO2 in subsurface pore space ($10-20/t)
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From page 252... ...
. NOTE: Carbon mineralization rates for basalt, olivine and shale in "damp", H2O-bearing, supercritical CO2 are approximately the same as carbonation rates for the same materials in aqueous fluid with the same P(CO2)
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From page 253... ...
were thought to be essential for olivine carbonation because of the perceptions that (a) aqueous fluids with high P(CO2)
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From page 254... ...
In natural systems, and proposed, engineered, in situ carbon mineralization involving subsurface reaction of CO2-bearing fluids with olivine-rich rocks, use of NaHCO3 would probably not be required to achieve the same effect, because reaction path modeling has repeatedly shown that low pH, CO2-rich fluids reacting with olivine-rich (ultramafic) rocks are rapidly buffered to high pH (e.g., Bruni et al., 2002; Paukert et al., 2012)
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From page 255... ...
The data in Figure 6.2C illustrate the basis for the widely held view that olivine-rich ultramafic rocks such as mantle peridotite dissolve faster than basalt and the plutonic equivalent of basalt, gabbro. Basalt and gabbro are rich in alumino-silicate minerals such as plagioclase feldspar with molar Ca/(Ca+Na)
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From page 256... ...
undergoes rapid carbonation during exposure of ultramafic mine tailings to air. Figure 6.4 compares rates of carbon mineralization at elevated P(CO2)
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From page 257... ...
situ carbon mineralization using heat-treated serpentine and CO2-rich fluids remain higher than injection of CO2 into subsurface pore space (Table 6.1)
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From page 258... ...
TABLE 6.1 Solid Storage of CO2 via Carbon Mineralization at Elevated P(CO2) and/or Temperature 258 CO2 reservoir Max CO2 produc- CO2 res- weight frac Weight frac- t CO2/ tion ervoir tion in 1 y at Gt/y Method tion CO2/hr km3/y Gt rock/y Gt rock rate in table CO2 $/t CO2 References Notes Ex situ carbon mineralization Peridotite Elevated tempera- 0.1-0.3 Some 0.1-0.5 0.02-0.1 50-100 Recent compre- 2, 3 and olivine ture and pressure fraction hensive reviews reaction with of 0.2 Gt by Bodenan et al., purified CO2 or ultramafic 2014; Chizmeshya et water saturated at tailings al., 2007; Gadikota high P(CO2)
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From page 259... ...
, ambient fraction of 0.02 temperature gas 0.2 through brucite powder + H2O Brucite Manufacture 0.3? Some 0.03-0.1 0.01- 200-600 Madeddu et al., 2 of brucite from fraction of 0.02 2015 mine tailings via 0.2 reaction at elevated temperature with NaOH-H2O solution, plus sparging with CO2-rich gas Serpentine Elevated tempera- Much slower Some 0.03-0.1 0.01- 200-600 Bodenan et al., 2, 4 ture and pressure re- than olivine fraction of 0.02 2014; Gerdemann action with purified 0.2 et al., 2007; Huijgen CO2 or water satu- et al., 2007; Khoo et rated at high P(CO2)
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From page 260... ...
TABLE 6.1 Continued 260 CO2 reservoir Max CO2 produc- CO2 res- weight frac Weight frac- t CO2/ tion ervoir tion in 1 y at Gt/y Method tion CO2/hr km3/y Gt rock/y Gt rock rate in table CO2 $/t CO2 References Notes Serpentine Elevated tempera- Still slower Some 0.03-0.1 0.01- 200-600 Hariharan et al., 2, 4 ture and pressure than olivine, fraction of 0.02 2013; Hariharan reaction with flue passivation 0.2 and Mazzotti, 2017; gas or water satu- problems Mazzotti personal rated in flue gas, communication, and/or with prior 2017; Sanna et al., heat treatment 2013, 2014; Werner et al., 2011, 2013, 2014 Wollastonite Elevated tempera- 0.2-0.6 0.00055 0.1 0.3 0.0002 80-160 Gerdemann et al., 1 ture and pressure 2007; Giannou reaction with puri- lakis et al., 2014; fied CO2 or water Huijgen et al., 2007; saturated at high O'Connor et al., P(CO2)
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From page 261... ...
± various weight frac pretreatment steps tion CO2 for steel slag to this com modity Construction Elevated tempera- Faster than 1.4-5.8 0.08-0.11 0.1-0.6 Probably Renforth et al., 2011 5 and demoli- ture and pressure wollastonite steel tion waste reaction with puri- slag cost fied CO2 or water divided saturated at high by ratio P(CO2) ± various of weight pretreatment steps fraction CO2 for steel slag to this commodity continued 261
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± various of weight pretreatment steps fraction CO2 for steel slag to this commodity
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± various weight frac pretreatment steps tion CO2 for steel slag to this com modity continued 263
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TABLE 6.1 Continued 264 CO2 reservoir Max CO2 produc- CO2 res- weight frac Weight frac- t CO2/ tion ervoir tion in 1 y at Gt/y Method tion CO2/hr km3/y Gt rock/y Gt rock rate in table CO2 $/t CO2 References Notes Bituminous Elevated tempera- Faster than 0.15-0.28 0.003-0.020 0.0004- Probably Renforth et al., 2011 5 ash ture and pressure wollastonite 0.006 steel reaction with puri- slag cost fied CO2 or water divided saturated at high by ratio P(CO2) ± various of weight pretreatment steps fraction CO2 for steel slag to this commodity Red mud, Elevated tempera- Faster than 0.12 0.04-0.07 0.00001- ~150 Gomes et al., 2016; 5 residue of ture and pressure wollastonite 0.006 International Alu Al2O3 extrac- reaction with puri- minium Institute, tion from fied CO2 or water 2018; Sanna et al., bauxite saturated at high 2014 P(CO2)
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From page 265... ...
Other alka- See comprehensive line wastes, list in Sanna et al., mostly 2014 produced at rates less than 0.01 Gt per year Ultramafic mine tailings at ambient temperature Ultramafic Sparging CO2-rich 0.03-0.30 1E8-1E9 0.200 0.03-0.10 0.006- 10-30 Assima et al., 2013a; mine tailings gas through mine 0.02 Harrison et al., 2013; tailings U.S. Geological Sur vey, 2018a, b, c In situ mineral carbonation Peridotite Drill to depth where 0.1-0.3 3E8-1E9 1-100 1E5-1E8 0.1-0.6 0.1-60 10-30 Kelemen and Mat- 6 temp > 90°C, inject ter, 2008; Kelemen CO2-rich fluid at et al., 2011, 2016; P(CO2)
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TABLE 6.1 Continued 266 CO2 reservoir Max CO2 produc- CO2 res- weight frac Weight frac- t CO2/ tion ervoir tion in 1 y at Gt/y Method tion CO2/hr km3/y Gt rock/y Gt rock rate in table CO2 $/t CO2 References Notes Basaltic Drill to depth where >0.0003 at >10,000 0.00003 0.01-0.25 3E7-8E6 10-30 Aradóttir personal 6 lava, specific temp > 25°C, inject CarbFix, ~ communication CarbFix and CO2-rich fluid at 0.001 at Wal- 2017; Gislason and Wallula sites P(CO2) > 60 bars lula Oelkers, 2014; Matter et al., 2016; Sigfusson et al., 2015; Xiong et al., 2018 Basaltic lava, Drill to depth where 1-100 1E5-1E6 0.01-0.25 0.01-25 10-30 McGrail et al., 2017a 7 global on- temp > 25°C, inject for Columbia River land flood CO2-rich fluid at Basalt and Deccan basalts P(CO2)
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2. Production and CO2 capacities assuming that peridotite, olivine, brucite, and/or serpentine are derived from serpentinized, ultramafic mine tailings.
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In altered ultramafic rocks, the minor mineral brucite (0 to 10% by weight) , together with asbestiform chrysotile serpentine, provides the best reactant for combined mineral capture and solid storage at low-temperature, near-surface conditions, for example in mine tailings.
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From page 269... ...
The mineral olivine, and rocks containing tens of percent olivine, such as mantle peridotite, ultramafic intrusions, and basaltic lavas, are widely available and react rapidly, and therefore are the most commonly considered solid reactants for carbon mineralization. Many industrial processes produce alkaline waste materials, such as steel slag, construction and demolition wastes, and cement kiln dust, that are rich in metal cations and have relatively low SiO2 and Al2O3 contents.
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From page 270... ...
in newly produced mine tailings would consume less than 36 million tons of CO2 per year. Because this storage capacity is small, the question arises whether one could mine ultramafic rock for the purpose of creating fine-grained rock reactants for CO2 mineral capture from air and storage.
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From page 271... ...
Rates of ultramafic mineral carbonation at ambient surface temperatures increase with elevated CO2 pressure (Figure 6.4) , suggesting that sparging CO2-rich gas or fluids through tailings piles could accelerate CO2 uptake in mine tailings for solid storage.
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From page 272... ...
Some of this could be overcome by stirring the tailings and similar lowcost methods. Grinding ultramafic or mafic basaltic rock reactants to smaller sizes than typical of mine tailings, and spreading them in agricultural soil, forest soil, or along beaches has been suggested as a means for CO2 removal from air (e.g., Schuiling and Krijgsman, 2006)
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From page 273... ...
IN SITU CARBON MINERALIZATION In situ storage -- via circulation of CO2-rich fluids (CO2-rich water or H2O-bearing supercritical CO2) in appropriate formations to form subsurface carbonate minerals -- addresses many of the problems of ex situ solid storage but remains a largely speculative alternative.
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From page 274... ...
,6.6 Relationship σ/µ, rate, and time required to achievea90% byrequired to achieve 90% by(covariance σ/µ, FIGURE mineral dissolution CV = 2.0) , mineral dissolution rate, and time particle size distribution volume mineral bution (covariance between initial mean particle size in typical volume dissolution of an arbitrary using a shrinking core an arbitrary mineraltime required to achieve 90% by volume dissolution of an arbitrary mineral CV = 2.0)
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Carbon Mineralization of CO2 275
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Side cores from the main borehole wall revealed the presence of abundant, newly formed carbonate minerals precipitated by reaction of the basalt with injected CO2, consistent with the composition of water in the borehole. Extensive surface studies and borehole observations for several years revealed no leakage of CO2 from the highly permeable horizon into which it was injected.
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From page 277... ...
Over the time span of several years to decades, passivation of reactive surfaces may decrease the mineralization rate. For this and other reasons, it is not known how much of the injected CO2 formed carbonate minerals, and how much still remains within fluid in pore space at the Wallula site.
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From page 278... ...
For Phase II, then, the mass fraction of CO2 within this volume is approximately 3.6 10-4 (~0.7 wt% carbonate minerals) and the CO2 uptake rate to date, in mass fraction per second, has been approximately 10-11/s over 3 years.
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From page 279... ...
Carbon Mineralization of CO2 FIGURE 6.9 Predicted concentration and isotope ratio of carbon in water at the CarbFix Phase I production well, based on observed concentration of conservative tracers such as SF6. NOTE: The observed deficit in carbon concentration and 14C are consistent with loss of consumption of almost all injected CO2 along the flow path to form solid carbonate minerals.
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From page 280... ...
There must be an annulus around the injection site where existing carbonate minerals dissolve in low pH fluid and new carbonate will not precipitate. As the fluid to rock ratio increases around the injection well over time, this low pH annulus is likely to grow, with a widening volume of dissolution of newly formed carbonate pushing the zone of new carbonate precipitation outward, as predicted via modeling by Aradóttir et al., 2012.
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From page 281... ...
However, recent addition of a ClimeWorks direct air capture unit at the CarbFix site serves as a concrete reminder that direct air capture systems, together with in situ carbon mineralization in basaltic lavas, could be a potent combination to achieve negative emissions. The CarbFix methodology can be seen as a two-stage storage technique, first trapping CO2 dissolved in water at depth, and then converting the dissolved CO2 to solid carbonate minerals over the time groundwater flows over 2,000 m.
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From page 282... ...
should not be overlooked. In Situ Carbon Mineralization in Peridotite and Other Ultramafic Rock Formations The classic paper of Barnes and O'Neil (1969)
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From page 283... ...
Keith Natural 20-200 4.0E+04 3.6E-03 9.0E+06 0.011 0.03-0.1 0 Wilson et al., 1, 2 rich in brucite Mine, AU percolation 2014 and fine chrysotile Mine tailings Diavik Natural 20-200 3.0E+04 4.0E-05 1.6E+04 0.002 0.03-0.1 0 Wilson et al., 1, 2, 3 rich in brucite Mine, CA percolation 2011 and fine chrysotile Serpentinite Black Lake Natural 20-200 6.0E+03 5.0E-05 2.0E+04 0.120 0.03-0.1 0 Pronost et al., 1, 2 mine tailings Mine, CA percolation 2012 Global Global Natural 20-200 0.200 <10 0.03-0.1 0 Dipple and ultramafic percolation Kelemen, mine tailings personal communica tion, 2017 Fractured Oman, Natural 1–1E6 3.3E-07 1.0E+03 50,000 0.60 0 Kelemen and 4, 5, 6 peridotite depth <3 groundwater Matter, 2008 aquifers km circulation 283 continued
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TABLE 6.2 Continued 284 Grain Rate CO2 Max CO2 size and weight reservoir CO2 weight crack Natural frac- produc- reser- fraction Cost spacing rate t/y tion Rate t CO2/ tion voir at rate in $/t Location Method microns CO2 CO2/y km3/y Gt rock/y Gt rock table CO2 References Notes Global On land, Natural 2–1E6 3.3E-07 1.0E+03 1E5-1E6 0.60 0 Kelemen et 4, 5, 6 fractured depth groundwater al., 2011 peridotite below circulation aquifers surface <3 km Global Seafloor, Natural 3–1E6 3.3E-07 1.0E+03 ~1E8 0.60 0 Kelemen et 4, 5, 6 fractured depth groundwater al., 2011 peridotite below circulation aquifers seafloor <3 km Soils Newcastle, Natural 1-100 4.6E-03 9.2E+06 ~ 0.015 0 Manning and 3, 7 contaminated UK percolation Renforth, with Ca-rich 2013; building Renforth waste et al., 2009; Washbourne et al., 2015 Enhanced processes Nearly pure Lab ex- Air sparged 2-40 9.9E-05 2.5E+05 0.200 <10 0.03-0.1 10-30 Harrison et 1 Mg(OH) 2 periment through al., 2013 from brucite brucite + mine H 2O
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From page 285... ...
Bioleaching Proposed Bioengi- 3.6E-3– 0.200 <10 0.03-0.1 10-30 Power et al., 7 and microbial neered 3.6E-2 2010, 2011, carbonate 2013a precipitation Thinner Generic Mechanical 3.6E-3– 0.200 <10 0.03-0.1 Assima et 7 distribution, 3.6E-2 al., 2013a; stirring of Harrison et ultramafic al., 2013; mine tailings Power et al., 2013c; Wilson et al., 2014 Ground Lab ex- Grinding and 0.01-1.0 5E-11– 0.025-0.25 28,000 0.05? 25- Hartmann 3, 8-11 peridotite periment broadcast 5E-10 115 et al., 2013; or basalt on Köhler et soils, beaches al., 2013; Montserrat et al., 2017; Renforth, 2012; Renforth et al., 2015; Rigopoulos et al., 2018 continued 285
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From page 286... ...
TABLE 6.2 Continued 286 Grain Rate CO2 Max CO2 size and weight reservoir CO2 weight crack Natural frac- produc- reser- fraction Cost spacing rate t/y tion Rate t CO2/ tion voir at rate in $/t Location Method microns CO2 CO2/y km3/y Gt rock/y Gt rock table CO2 References Notes Produce Generic Drill, pump if NA ~10? Kelemen et 5, 12, alkaline necessary al., 2016 13 water from peridotite aquifers Circulate Generic Drill to depth 1–1E6 1.5E-4– 4.5E5–4.5E6 1E5-1E8 0.60 30-60 Kelemen 5, 14 water where temp 1.5E-3 et al., 2011, through high ~90°C, flow 2016 permeability and recharge peridotite driven by hy aquifers drothermal via thermal convection, convection permeability 10-12 m2 Circulate Too costly Drill to depth 1–1E6 1.5E-4– 4.5E5–4.5E6 1E5-1E8 0.60 3,000- Kelemen et 5, 11, water where temp 1.5E-3 6,000 al., 2016 14 through low ~ 90°C, flow permeability and recharge peridotite driven by aquifers via pumping, pumping permeability 10–14 m2
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2. Impacts may be confined to mine tailings sites, assumed density of tailings 2.5 t/m3.
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From page 288... ...
14. Crystallization of carbonate minerals in subsurface could destroy permeability and armor reactive surfaces, or alternatively could maintain or enhance permeability and reactive surface area via reaction-driven cracking (Jamtveit et al., 2008; Kelemen and Hirth, 2012; MacDonald and Fyfe, 1985; Zhu et al., 2016)
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From page 289... ...
Olivine and brucite undergo rapid carbonation because their solubility in aqueous fluids is moderately high, and intra-mineral diffusion is relatively fast, compared to rock-forming alumino-silicate minerals such as plagioclase feldspars, which are abundant in basalt. Second, high solubilities and rapid reaction rates for carbon mineralization in olivine and other minerals in mantle peridotite are due, in part, to the fact that they are far from CO2, H2O, and O2 exchange equilibrium with air and surface waters.
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From page 290... ...
. Alkaline spring waters are interpreted as products of precipitation of Mg-carbonate minerals during reaction of groundwater with peridotite, together with dissolution of Ca-bearing silicates in peridotite (e.g., pyroxenes and plagioclase)
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From page 291... ...
Many of these record replacement at ~ 100°C, within the temperature range where carbon mineralization rates are high. The presence of listvenites reveals that there are natural pathways to complete reaction under such temperature conditions, despite potential negative feedbacks discussed in the "Feedbacks between reaction and fluid flow during in situ carbon mineralization" section.
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From page 292... ...
The combination of these five factors has sustained basic research on natural and engineered in situ carbon mineralization in peridotite massifs for a decade. However, there have been no field-scale investigations of engineered, in situ carbonation of peridotite.
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From page 293... ...
Filling of pore space with reaction products may reduce permeability and armor reactive surfaces, forming a solid diffusive boundary layer between fluid and solid reactants. These negative feedbacks may commonly cause peridotite carbonation (and hydration and oxidation)
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From page 294... ...
may be a very small-scale result of the reaction-driven cracking process, in which observed layers of amorphous SiO2 on olivine surfaces (Béarat et al., 2006; Chizmeshya et al., 2007) fracture and spall off dissolving grains, or are "pushed" from the surface by precipitating reaction products.
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From page 295... ...
If natural systems can do it, it is likely to be possible to design engineered systems that emulate this process. Moreover, understanding of the feedbacks that lead to reaction-driven cracking could be applied to geothermal power generation, in situ mining for, for example, uranium, and extraction of oil and gas 295
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From page 297... ...
in 2D model of a tabular zone of high porosity infiltrated by CO2-rich fluid, reacting with olivine to produce carbonate minerals with volume expansion.
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From page 298... ...
Ongoing research seeks to outline a "phase diagram" delineating the conditions for reaction-driven cracking, and the surrounding parameter space dominated by clogging and armoring of reactive surfaces. Solid storage of CO2 via in situ carbon mineralization in peridotite Kinetic data summarized in the "Carbon Mineralization Kinetics" section yield empirical predictions of olivine carbonation rates (mass fraction olivine ≤ 75 microns)
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From page 299... ...
weathering, shallow groundwater, equilibrated with atmospheric CO2, reacts with peridotite in the subsurface, in a system closed to CO2 exchange with the atmosphere. This quickly reduces dissolved carbon concentrations to zero, via precipitation of Mgand Ca-carbonate minerals in veins (Figure 6.11)
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From page 300... ...
An exception could be co-located geothermal power generation and CO2 capture. Large geothermal power plants commonly employ pumps at the surface and within boreholes, optimizing the flow rate to generate maximum electricity at a minimum pumping rate.
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From page 301... ...
Where peridotite is abundant, then, this could be the optimal storage method for CO2. And finally, as for direct air capture via in situ carbon mineralization driven by circulation of surface water through peridotite, in situ CO2 storage via injection of CO2-rich fluids into peridotite could be combined with geothermal power generation.
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From page 302... ...
In addition, in some cases ex situ carbon mineralization acts to mitigate environmental hazards.
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From page 303... ...
SUMMARY: COST AND CAPACITY OF CARBON MINERALIZATION METHODS This chapter outlined several proposed methods for engineered acceleration of natural carbon mineralization processes, to achieve either solid storage of CO2, or combined mineral capture from air and storage. Here we summarize the data in Tables 6.1 and 6.2 to provide a concise evaluation of the cost and capacity for various proposed methods, as compared to direct air capture systems and/or storage of supercritical CO2 fluid in pore space.
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From page 304... ...
Combined mineral capture from air and solid storage, via surficial processes using existing ultramafic mine tailings, could be a relatively inexpensive and straightforward technology, but has a limited storage capacity. Current, highly approximate cost estimates suggest that mining, crushing, and perhaps additional milling of appropriate lithologies -- with a focus on mantle peridotite -- for the purpose of mineral capture from air and storage via enhanced weathering may be cost-competitive with direct air capture systems, within the uncertainties for cost estimates for each type of process (Figure 6.20)
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From page 305... ...
, or mass fraction per second at a common grain size, is a worthy research goal in itself, and would likely reveal a need for additional, comparative experimental studies. Ex Situ Carbon Mineralization Laboratory studies of ex situ carbon mineralization processes for CO2 storage have been extensive and are ongoing.
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From page 306... ...
Rock reactants, particularly mantle peridotite, could potentially be used to achieve this conversion (e.g., McCollom et al., 2010) , although direct air capture technologies may be a less expensive source of CO2.
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From page 307... ...
Carbonation of industrial wastes to mitigate hazards is of potential interest to EPA and DOE. A basic research area with high potential, but whose effectiveness and cost are currently impossible to assess, is microbial acceleration of carbon mineralization in mine tailings (e.g., Power et al., 2013a)
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From page 308... ...
. Work has focused on local modifications to ultramafic mine tailings, particularly mine tailings from highly altered serpentinites that include abundant brucite (and asbestiform chrysotile)
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From page 309... ...
In the United States, this exploration might be best undertaken by the USGS. In Situ Carbon Mineralization in Basaltic Lavas The Wallula and CarbFix projects have established the viability of combined CO2 storage in pore space and carbon mineralization in basaltic lavas.
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From page 310... ...
Recommended laboratory experiments and numerical modeling studies to address these feedbacks for in situ carbon mineralization in basaltic lavas are essentially identical to those for in situ mineralization in ultramafic rocks (see the next section, "In situ Carbon Mineralization in Ultramafic Rocks")
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From page 311... ...
They could also be used to optimize engineered methods to achieve rapid carbon mineralization and minimize negative feedbacks. We envision multistep pilot projects on in situ carbon mineralization in ultramafic rocks, with gradually increasing cost, ambition, and risk and funded by DOE, USGS, and/or state sources, ideally in combination with industry partners.
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From page 312... ...
Assuming that geologically and socially appropriate sites can be identified, a next step would be to produce water from existing, alkaline, carbon-depleted aquifers for direct uptake of CO2 from air to form carbonate minerals in travertine deposits on the surface, and dissolved bicarbonate in surface water. The size, permeability, productivity, and physical and chemical recharge rates of such aquifers are unknown and could readily be evaluated for several sites at a relatively low cost.
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From page 313... ...
. Cost of the Research Agenda There is far less experience and data on even kiloton-per-year storage of CO2 via carbon mineralization, let alone megaton- and gigaton-per-year processes, compared to experience and data on storage of supercritical CO2 in deep sedimentary formations.
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From page 314... ...
, fluid composition to establish quantitative framework and enable comparisons and optimization. Rock mechanics 6 2 $6M 10 $60M Frontier: exploration of positive and negative feedbacks between reaction and fluid flow, for in situ carbon mineralization, in situ mining, geothermal power generation, extraction of oil and gas from tight reservoirs, ensuring integrity of reservoir caprock and wellbore cement.
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From page 315... ...
Determine the carbon storage limits that can be achieved with mineral addition. Studying the 8 4 $10M 10 $100M STU, C, OENV, G, PBSU environmental impact of mineral addition to terrestrial, coastal and marine environments continued 315
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From page 316... ...
TABLE 6.3 Continued 316 Number of Total cost/project/ academic/national year lab/ industrial partnerships Pilot Studies Ex situb 2 $250K $500K 10 $5M C, EN, OENV, G, M&V, PBSU Mine tailings, alkaline 4 $250K $1M 10 $10M STU, C, EN, OENV, G, M&V, PBSU wastes Soils, beaches 3 $1M $3M 10 $30M Frontier: Challenging field scale characterization of slow rates over large areas with poor controls on natural inputs and outputs In situ basaltc 1 $10M $10M 10 $100M STU,C, EN, OENV, G, M&V, PBSU
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From page 317... ...
b Lab kinetics above, relevant to all categories, but leave larger-scale ex situ studies to the carbon capture, utilization, and storage community. c Constant annual cost listed here, phased project with increasing annual expenses for successive phases described in text and Appendix F, Table F.3.
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From page 318... ...
N E G AT I V E E M I S S I O N S T E C H N O LO G I E S A N D R E L I A B L E S E Q U E S T R AT I O N Research topics spanning NSF and DOE domains could be facilitated by establishing a formal NSF-DOE partnership, focused on funding research on greenhouse gas mitigation (not restricted to CO2 removal from air)
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