Flare gas-to-power by direct intercooled oxy-combustion supercritical CO2 power cycles

Radial inflow turbines are a relevant architecture for energy extraction from supercritical CO2 power cycles for scales less than 10 MW. To ensure stage and overall cycle efficiency, it is desirable to recover exhaust energy from the turbine stage through the inclusion of a suitable diffuser in the turbine exhaust stream. In supercritical CO2 Brayton cycles, the high turbine inlet pressure can lead to sealing challenges at small scale if the rotor is supported from the rotor rear side in the conventional manner. An alternative is a layout where the rotor exit faces the bearing system. While such a layout is attractive for the sealing system, it limits the axial space claim of the diffuser. Designs of a combined annular-radial diffuser are considered as a means to meet the aforementioned packaging challenges of this rotor layout. Diffuser performance is assessed numerically with the use of Reynolds-averaged Navier--Stokes (RANS) and unsteady Reynolds-averaged Navier--Stokes (URANS) calculations. To appropriately account for cross coupling with the stage, a single blade passage of the entire stage is modeled. Assessment of diffuser inlet conditions, and off-design performance analysis, reveals that the investigated diffuser designs are performance robust to high swirl, high inlet blockage, and highly nonuniform mass flux distribution. Diffuser component performance is dominated by the annular-radial bend. The incorporation of a constant sectional area bend is the key geometric feature in rendering the highly nonuniform turbine exit flow (dominated by tip clearance flows at the shroud) more uniform.

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Recuperated versus single-recuperator re-compressed supercritical CO2 Brayton power cycles for DEMO fusion reactor based on dual coolant lithium lead blanket

Energy ◽

10.1016/j.energy.2017.08.105 ◽

2017 ◽

Vol 140 ◽

pp. 307-317 ◽

Cited By ~ 17

Author(s):

José Ignacio Linares ◽

Alexis Cantizano ◽

Eva Arenas ◽

Beatriz Yolanda Moratilla ◽

Víctor Martín-Palacios ◽

...

Keyword(s):

Supercritical Co2 ◽

Fusion Reactor ◽

Power Cycles

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Experimental investigation of thermal-hydraulic performance of discontinuous fin printed circuit heat exchangers for supercritical CO2 power cycles

Experimental Thermal and Fluid Science ◽

10.1016/j.expthermflusci.2019.04.025 ◽

2019 ◽

Vol 106 ◽

pp. 119-129 ◽

Cited By ~ 10

Author(s):

Sandeep R. Pidaparti ◽

Mark H. Anderson ◽

Devesh Ranjan

Keyword(s):

Experimental Investigation ◽

Heat Exchangers ◽

Supercritical Co2 ◽

Hydraulic Performance ◽

Power Cycles ◽

Printed Circuit

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Analysis of supercritical CO2 Brayton power cycles in nuclear and fusion energy

Fusion Engineering and Design ◽

10.1016/j.fusengdes.2019.02.119 ◽

2019 ◽

Vol 146 ◽

pp. 1520-1523 ◽

Cited By ~ 15

Author(s):

Jan Syblik ◽

Ladislav Vesely ◽

Slavomir Entler ◽

Jan Stepanek ◽

Vaclav Dostal

Keyword(s):

Supercritical Co2 ◽

Fusion Energy ◽

Power Cycles

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Turbomachinery for Supercritical CO2 Power Cycles

Volume 5: Manufacturing Materials and Metallurgy; Marine; Microturbines and Small Turbomachinery; Supercritical CO2 Power Cycles ◽

10.1115/gt2012-68735 ◽

2012 ◽

Cited By ~ 8

Author(s):

Robert Fuller ◽

Jason Preuss ◽

Jeff Noall

Keyword(s):

Coal Combustion ◽

Supercritical Co2 ◽

Waste Heat ◽

Heat Sources ◽

Clean Coal ◽

Power Cycles ◽

Different Types ◽

Type Size ◽

Turbo Machinery ◽

Machinery Design

Supercritical CO2 (S-CO2) power cycles offer high plant efficiencies and beneficial economics for variety of heat sources. Nuclear, solar, waste heat, energy storage, and clean coal combustion are some of the applications under consideration for S-CO2 power production. Different types of cycles, topping and bottoming, have been conceptualized based on the heat source. These cycles have the possibility of being economically beneficial and competitive against incumbent steam cycles, primarily due to reduced material costs. Often the turbo-machinery capabilities are overlooked during the cycle design process, or are not well understood. A method and guideline for turbo machinery selection is offered. Several examples are offered to give the S-CO2 cycle designer to judge the compatibility of the turbo-machinery with the overall system including type, size, and efficiency. The guideline includes turbo machinery design limitations. Understanding the turbo machinery implications relative to cycle design will allow the system designer to optimize the plant for efficiency and positive economic outcome.

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Supercritical CO2 Brayton power cycles for DEMO fusion reactor based on Helium Cooled Lithium Lead blanket

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2014.10.093 ◽

2015 ◽

Vol 76 ◽

pp. 123-133 ◽

Cited By ~ 24

Author(s):

José Ignacio Linares ◽

Luis Enrique Herranz ◽

Iván Fernández ◽

Alexis Cantizano ◽

Beatriz Yolanda Moratilla

Keyword(s):

Supercritical Co2 ◽

Fusion Reactor ◽

Power Cycles

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Corrosion and Erosion Behavior in Supercritical CO2 Power Cycles

Volume 3B: Oil and Gas Applications; Organic Rankine Cycle Power Systems; Supercritical CO2 Power Cycles; Wind Energy ◽

10.1115/gt2014-25136 ◽

2014 ◽

Cited By ~ 3

Author(s):

Darryn Fleming ◽

Alan Kruizenga ◽

James Pasch ◽

Tom Conboy ◽

Matt Carlson

Keyword(s):

Carbon Dioxide ◽

Stainless Steel ◽

Intergranular Corrosion ◽

Supercritical Co2 ◽

Power Production ◽

Operating Conditions ◽

Working Fluid ◽

Power Cycles ◽

Power Cycle ◽

Potential Issue

Supercritical Carbon Dioxide (S-CO2) is emerging as a potential working fluid in power-production Brayton cycles. As a result, concerns have been raised regarding fluid purity within the power cycle loops. Additionally, investigations into the longevity of the S-CO2 power cycle materials are being conducted to quantify the advantages of using S-CO2 versus other fluids, since S-CO2 promises substantially higher efficiencies. One potential issue with S-CO2 systems is intergranular corrosion [1]. At this time, Sandia National Laboratories (SNL) is establishing a materials baseline through the analysis of 1) “as received” stainless steel piping, and 2) piping exposed to S-CO2 under typical operating conditions with SNL’s Brayton systems. Results from ongoing investigations are presented. A second issue that SNL has discovered involves substantial erosion in the turbine blade and inlet nozzle. It is believed that this is caused by small particulates that originate from different materials around the loop that are entrained by the S-CO2 to the nozzle, where they impact the inlet nozzle vanes, causing erosion. We believe that, in some way, this is linked to the purity of the S-CO2, the corrosion contaminants, and the metal particulates that are present in the loop and its components.

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Modeling and experimental results for condensing supercritical CO2 power cycles.

10.2172/1030354 ◽

2011 ◽

Cited By ~ 6

Author(s):

Steven Alan Wright ◽

Thomas M. Conboy ◽

Ross F. Radel ◽

Gary Eugene Rochau

Keyword(s):

Supercritical Co2 ◽

Experimental Results ◽

Power Cycles

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Impact of Plant Siting on Performance and Economics of Indirect Supercritical CO2 Coal Fired Power Plants

10.1115/gt2021-58867 ◽

2021 ◽

Author(s):

Sandeep R. Pidaparti ◽

Charles W. White ◽

Nathan T. Weiland

Keyword(s):

Supercritical Co2 ◽

Optimization Design ◽

Power Plants ◽

Waste Heat ◽

The United States ◽

Attractive Alternative ◽

Plant Design ◽

Power Cycles ◽

The Impact ◽

And Storage

Abstract Indirect-fired supercritical CO2 (sCO2) power cycles are being explored as an attractive alternative to steam Rankine cycles for a variety of heat sources including fossil, concentrated solar power (CSP), nuclear, waste heat, etc. Due to the near-ambient CO2 critical temperature of 31°C, the effects of ambient temperature on sCO2 power cycles performance are expected to be more significant than for steam Rankine cycles. This study presents the impact of plant siting on the performance and economics of coal-fired utility scale power plants based on indirect sCO2 power cycles with carbon capture and storage (CCS). Four different plant sites across the United States have been selected for investigation: Chicago, IL; Kemmerer, WY; Houston, TX; Knoxville, TN. For each plant site, local parameters such as design ambient conditions, coal type and prices, captured CO2 transportation and storage (T&S) costs are considered for the techno-economic analyses (TEA). To determine the optimum plant design for each location, two power cycle configurations (recompression cycle, partial cooling cycle with reheat) and two cooling technologies (dry and adiabatic cooling) are examined. The optimization was conducted using automated derivative-free optimization (DFO) algorithms available under NETL’s Framework for Optimization and Quantification of Uncertainty and Sensitivity (FOQUS) platform. The optimization design variables include parameters such as turbine inlet temperatures and pressure, sCO2 cooler outlet temperatures, recuperators approach temperature and pressure drop etc. The study demonstrates the variability in optimal plant design for different ambient and fuel input conditions. The results will be used in future sCO2 technology market analyses.

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