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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Novel Flow Sheet for Low Energy CO 2 Capture Enabled by Biocatalyst Delivery System

This report documents a preliminary Techno-Economic Assessment (TEA) for processes utilizing Akermin’s second generation biocatalyst delivery system to enhance AKM24, a non- volatile salt solution for CO 2 capture. Biocatalyst enhanced AKM24 offers the potential to reduce the cost of CO 2 capture in flue gas applications due to its improved equilibrium and stoichiometric properties that result in double the absorption capacity relative to previously demonstrated biocatalyst enhanced solvents. The study assumes a new supercritical pulverized coal fired power plant with a net output of 550 MWe after 90% CO 2 capture and uses the June 2011 cost basis (August 2012 update of Bituminous Baseline Study, or BBS). Power plant modeling, capital cost review, and economic calculations were provided by WorleyParsons. Rate-based CO2 capture process modeling and equipment sizing was performed by Akermin using AspenPlus® V8.4, customized to accurately predict thermodynamics, kinetics, and physical properties of the AKM-24 solvent based on available laboratory data. Equipment capital costs were estimated using Aspen Process Economic Analyzer™ which compared well with published baseline cost estimates. Quotes of equipment costs and power consumption for vacuum blower and CO 2 compression equipment were also provided by Man Diesel & Turbo. Three process scenarios were examined for Akermin biocatalyst enhanced solvent systems including: Case-1A: an absorption-desorption system operated with a reboiler pressure of 0.16 bara (60°C); Case-2A: an absorption-desorption system with moderate vacuum assisted regeneration at 0.40 bara (80°C); and finally, Case-2B: a conventional absorption-desorption system with near atmospheric pressure regeneration at 1.07 bara (105°C). The estimated increases in cost of electricity (ICOE) for these cases were $58.1/MWh, $47.3/MWh and $46.4/MWh, respectively. Case 2B had the best results for this analysis achieving an estimated 30% reduction in ICOE relative to the NETL Case 12 (v2) baseline of $66.3/MWh ICOE. Likewise, Case-2B achieved capture costs of $53.0/tCO2 and 65.7/tCO 2 avoided, which equates to 20.2% and 31.4% savings relative to the Case 12 baseline ($66.4/tCO 2 and $95.9/tCO 2 avoided). While Case 2A and 2B have similar results, Case 2A requires further development. Focus on Case 2B is recommended for this project because its cost performance is closest to the DOE goals, and has it has the best potential to achieve a successful demonstration at the next scale.

Reardon, John↗
DOE OSTI2022

Making Grid-interactive Efficient Buildings a “Win” for Both Customers and Utilities

Buildings account for more than 70% of U.S. electricity use and at least one-third of U.S. economy-wide CO2 emissions. Changing the timing and overall amount of electricity consumption in buildings would significantly reduce energy costs to consumers and facilitate the transition to a decarbonized economy. Grid-interactive efficient buildings (GEBs) incorporate energy efficiency, smart technologies, and active use of distributed energy resources (DERs) to provide these benefits. As the link between the customer and the power system, utilities are central to widespread deployment of GEBs. Yet, despite the significant cost savings and operational benefits of GEBs for utilities, deployment has remained limited. This paper explores emerging models for enabling utilities to facilitate GEB adoption. Building off foundational research conducted to develop the U.S. DOE’s A National Roadmap for Grid-Interactive Efficient Buildings, we describe the most novel recent examples of ways in which utilities and regulators have made demand-side innovation a win for both the customer and the utility. Emerging concepts include: (1) performance incentive mechanisms to align GEB deployment with utility financial motivations, (2) the use of subscription pricing (i.e., fixed monthly bills) to promote load flexibility and energy efficiency, (3) rate-basing utility-controlled behind-the-meter assets, and (4) coupling energy efficiency and load flexibility with electrification proposals to ensure that customer benefits are maximized. The paper concludes with a discussion about prospects for widespread GEB deployment and utilization by utilities, and how to scale efforts.

Satchwell, Andrew↗
DOE OSTI2022

Heat Loss Characteristics and Energy Use of Piperazine with the Advanced Stripper (PZAS) at the UT-SRP Pilot Plant

Heat duty and heat loss were measured at the pilot plant at UT Austin. Heat loss was measured with energy balances using water. Heat loss was studied using surface temperature measurements over 68 different locations at the pilot plant. Surface temperature measurements indicated that bare metal surfaces were the primary source of heat loss from the pilot plant. Heat loss from bare metal surfaces was at least 50% controlled by natural convection and in many cases was as high as 75% natural convection controlled. Measured heat loss at the pilot plant was 20100 BTU/hr and overall heat loss did not show any dependence on the heat rate of the plant. Compared to PZAS™ at the National Carbon Capture Center, heat loss relative to heat rate was higher at 38%. The relative heat loss at the pilot plants was found to decrease by 20% per MW of added capacity. Measured net heat duty was found to be dependent on measured lean loading and cold rich bypass flow rate. Measured net heat duty was between 2.2 and 2.4 GJ/tonne at an optimum lean loading of 0.2–0.21 mol/mol. Data reconciliation by Aspen Plus® Data Fit™ underpredicted CO2 flow rate by 20% due to an overprediction of lean loading by 19%, indicating a necessary change in thermodynamic parameters in the model. This resulted in an over prediction of heat duty by 33% on average.

Amine scrubbing, stripper, energy requirement, hea↗
DOE OSTI2011

Dynamic Absorption Model for Off-Gas Separation

Modeling and simulations will aid in the future design of U.S. advanced reprocessing plants for the recovery and recycle of actinides in used nuclear fuel. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, a rate based, dynamic absorption model is being developed in gPROMS software. Inputs include liquid and gas stream constituents, column properties, liquid and gas phase reactions, number of stages, and inlet conditions. It simulates multiple component absorption with countercurrent flow and accounts for absorption by mass transfer and chemical reaction. The assumption of each stage being a discrete well-mixed entity was made. Therefore, the model is solved stagewise. The simulation outputs component concentrations in both phases as a function of time from which the rate of absorption is determined. Temperature of both phases is output as a function of time also. The model will be used able to be used as a standalone model in addition to in series with other off-gas separation unit operations. The current model is being generated based on NOx absorption; however, a future goal is to develop a CO2 specific model. The model will have the capability to be modified for additional absorption systems. The off-gas models, both adsorption and absorption, will be made available via the server or web for evaluation by customers.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗