Assessment of Nuclear Energy to Support Negative Emission Technologies

Published: Sept. 7, 2023

The feasibility and performance of nuclear energy coupled with Negative Emission Technology (NET) processes were investigated in this report. Three overarching questions from NET systems guided research: which would be able to use heat and/or electricity power plants (NPPs); what is the cost a system; market outlook for system? Among various NETs that are actively being developed, several found potentially benefit coupling an NPP via (1) large amounts decarbonized constant-output electricity; (2) free waste or cheap low-temperature heat; (3) high-temperature heat. NPPs compatible Direct Air Capture (DAC) systems, detailed techno-economic analysis NPP&DAC was performed. Preliminary also indicated biomass water-based NPPs, but further work needed quantify these systems. Design analyses completed both liquid solvent DAC (L-DAC) solid sorbent (S-DAC) technologies. A 1.0-GWth L-DAC S-DAC capture 12–15 Mt CO2/yr 1.0–1.5 CO2/yr, respectively. While process enables much greater CO2 than when sized 1 GWth NPP, NPP&L-DAC system considered requires >2 natural gas oxy-combustion reach adequate temperature calciner. generated combustion captured as part calcination process, addition air, resulting overall sequestration close 30% more air. carbon calculated levelized (LCOD) had range $\$170–260$/tCO2 $\$650–680$/tCO2 NPP&S-DAC For provides economic compared previous National Energy Laboratory (NETL) studies non-nuclear leading reduction LCOD by 5–7% L-DAC, 8–13% S-DAC. preliminary reviewed potential prices eligibility incentives. estimated revenues (coming federal incentive, commodity markets, offset market) $\$170–979$ tCO2, results show because lower LCOD, attractive process. investment require long-term certainty sufficient size, prices, Enabling ramp operation up down based on price not expected significantly increase system. This required very high justify deployment continuous expensive In analysis, new research uncovered, follow-up recommended investigation, including study other such pyrolysis gasification storage, seawater capture.

Language: Английский

---

Reaction Layer Formation on MgO in the Presence of Humidity

ACS Applied Materials & Interfaces, Journal Year: 2023, Volume and Issue: 16(1), P. 712 - 722

Published: Dec. 29, 2023

Mineralization by MgO is an attractive potential strategy for direct air capture (DAC) of CO2 due to its tendency form carbonate phases upon exposure water and CO2. Hydration during this process typically assumed not be rate limiting, even at ambient temperatures. However, surface passivation hydrated likely reduces the capacity. Here, we examine initial hydration reactions that occur on MgO(100) surfaces determine whether they could potentially impact uptake. We first used atomic force microscopy (AFM) explore changes in reaction layers (pH = 6 12) MgO-saturated solution 11) found are heterogeneous nonuniform. To how relative humidity (R.H.) affects reactivity, reacted samples room temperature nominally dry N2 (∼11–12% R.H.) up 12 h, humid (>95% 5, 10, 15 min, 33 75% R.H. 8 days. X-ray reflectivity electron analysis reveal rapidly air, but growth layer slows after formation. Reaction thickness strongly correlated with R.H., denser forming compared 33% or N2. The amorphous poorly crystalline based grazing incidence diffraction measurements. After days, increases density as sample 5–15 min. This may represent step toward crystallization layer. Overall, high favors formation a hydrated, disordered MgO. Based our results, DAC location higher will favorable, slow significantly from rates short timescales, presumably passivation.

Language: Английский

---

Carbon dioxide sequestration through mineralization from seawater: The interplay of alkalinity, pH, and dissolved inorganic carbon

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 500, P. 156380 - 156380

Published: Oct. 5, 2024

Language: Английский

---

Seawater Enables High-Quality Carbon Removal

˜The œminerals, metals & materials series, Journal Year: 2024, Volume and Issue: unknown, P. 95 - 100

Published: Jan. 1, 2024

Language: Английский

---

Comment on egusphere-2024-108

Published: Feb. 29, 2024

Abstract. Ocean alkalinity enhancement (OAE) is a promising approach to marine carbon dioxide removal (mCDR) that leverages the large surface area and storage capacity of oceans sequester atmospheric CO₂ as dissolved bicarbonate (HCO₃^-). The SEA MATE (Safe Elevation Alkalinity for Mitigation Acidification Through Electrochemistry) process uses electrochemistry convert some salt (NaCl) in seawater or brine into aqueous acid (HCl), which removed from system, base (NaOH), returned ocean with remaining seawater. resulting increase pH causes shift inorganic (DIC) speciation toward carbonate decrease surface-ocean pCO₂. pCO­₂ results enhanced CO₂ uptake reduced loss by due gas exchange. net result this DIC, where it durably stored as mostly carbonate. In study, we systematically test efficiency treated NaOH at beaker (1 L), aquaria (15 tank (6000 L) scales establish operational boundaries safety scaling up field experiments. Preliminary show equilibration occurred on order weeks months, depending circulation, air forcing, bubbling conditions within tanks. An ~0.7–0.9 mol DIC/ added (in form NaOH) was observed through analysis bottle samples sensor data, consistent value expected given values system equilibrium calculations range salinities temperatures tested. Mineral precipitation when bulk exceeded 10.0 Ω_aragonite exceeded 30.0. This dominated Mg(OH)₂ over hours 1 day before shifting CaCO_{3, aragonite} precipitation. These combined models dilution advection alkaline plumes, will allow estimation amount OAE pilot studies. Future experiments should better approximate including sediment interactions, biological activity, air-sea exchange rates, mixing-zone dynamics.

Language: Английский

---