Techno-Economic Evaluation of Pressurized Oxy-Fuel Combustion Systems

Author(s):  
Jongsup Hong ◽  
Ahmed F. Ghoniem ◽  
Randall Field ◽  
Marco Gazzino

Oxy-fuel combustion coal-fired power plants can achieve significant reduction in carbon dioxide emissions, but at the cost of lowering their efficiency. Research and development are conducted to reduce the efficiency penalty and to improve their reliability. High-pressure oxy-fuel combustion has been shown to improve the overall performance by recuperating more of the fuel enthalpy into the power cycle. In our previous papers, we demonstrated how pressurized oxy-fuel combustion indeed achieves higher net efficiency than that of conventional atmospheric oxy-fuel power cycles. The system utilizes a cryogenic air separation unit, a carbon dioxide purification/compression unit, and flue gas recirculation system, adding to its cost. In this study, we perform a techno-economic feasibility study of pressurized oxy-fuel combustion power systems. A number of reports and papers have been used to develop reliable models which can predict the costs of power plant components, its operation, and carbon dioxide capture specific systems, etc. We evaluate different metrics including capital investments, cost of electricity, and CO2 avoidance costs. Based on our cost analysis, we show that the pressurized oxy-fuel power system is an effective solution in comparison to other carbon dioxide capture technologies. The higher heat recovery displaces some of the regeneration components of the feedwater system. Moreover, pressurized operating conditions lead to reduction in the size of several other critical components. Sensitivity analysis with respect to important parameters such as coal price and plant capacity is performed. The analysis suggests a guideline to operate pressurized oxy-fuel combustion power plants in a more cost-effective way.

2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Peter Ohlemüller ◽  
Jan-Peter Busch ◽  
Michael Reitz ◽  
Jochen Ströhle ◽  
Bernd Epple

Chemical-looping combustion (CLC) is an emerging carbon capture technology that is characterized by a low energy penalty, low carbon dioxide capture costs, and low environmental impact. To prevent the contact between fuel and air, an oxygen carrier is used to transport the oxygen needed for fuel conversion. In comparison to a classic oxyfuel process, no air separation unit is required to provide the oxygen needed to burn the fuel. The solid fuel, such as coal, is gasified in the fuel reactor (FR), and the products from gasification are oxidized by the oxygen carrier. There are promising results from the electrically heated 100 kWth unit at Chalmers University of Technology (Sweden) or the 1 MWth pilot at Technische Universität Darmstadt (Germany) with partial chemical-looping conditions. The 1 MWth CLC pilot consists of two interconnected circulating fluidized bed reactors. It is possible to investigate this process without electrically heating due to refractory-lined reactors and coupling elements. This work presents the first results of autothermal operation of a metal oxide CLC unit worldwide using ilmenite as oxygen carrier and coarse hard coal as fuel. The FR was fluidized with steam. The results show that the oxygen demand of the FR required for a complete conversion of unconverted gases was in the range of 25%. At the same time, the carbon dioxide capture efficiency was low in the present configuration of the 1 MWth pilot. This means that unconverted char left the FR and burned in the air reactor (AR). The reason for this is that no carbon stripper unit was used during these investigations. A carbon stripper could significantly enhance the carbon dioxide capture efficiency.


Author(s):  
Patricia Seevam ◽  
Julia Race ◽  
Martin Downie ◽  
Julian Barnett ◽  
Russell Cooper

Climate change has been attributed to green house gases, with carbon dioxide (CO2) being the main contributor. Sixty to seventy percent of carbon dioxide emissions originate from fossil fuel power plants. Power companies in the UK, along with oil and gas field operators, are proposing to capture this anthropogenic CO2 and either store it in depleted reservoirs or saline aquifers (carbon capture and storage, CCS), or use it for ‘Enhanced Oil Recovery’ (EOR) in depleting oil and gas fields. This would involve extensive onshore and offshore pipeline systems. The decline of oil and gas production of reservoirs beyond economic feasibility will require the decommissioning onshore and offshore facilities post-production. This creates a possible opportunity for using existing pipeline infrastructure. Conversions of pipelines from natural gas service to CO2 service for EOR have been done in the United States. However, the differing sources of CO2 and the differing requirements for EOR and CCS play a significant part in allowing the re-use of existing infrastructure. The effect of compositions, the phase of transportation, the original pipeline specifications, and also the pipeline route require major studies prior to allowing re-use. This paper will first review the requirements for specifying the purity of the CO2 for CCS and to highlight the implications that the presence of impurities and the current water specifications for pipelines has on the phase diagram and the associated physical properties of the CO2 stream. A ‘best’ and ‘worst’ case impurity specification will be identified. Then an analysis on the impact and subsequent validation, of equations of state based on available experimental data on the phase modelling of anthropogenic CO2 is presented. A case study involving an existing 300km gas pipeline in the National Transmission System (NTS) in the UK is then modelled, to demonstrate the feasibility of using this pipeline to transport anthropogenic CO2. The various issues involved for the selected ‘best’ and ‘worst’ case specification are also covered. This is then followed by an investigation of the options for transport in the ‘gas’ phase and ‘supercritical’ phases, and also identifying the limitations on re-using pipeline infrastructure for CCS.


2021 ◽  
Vol 2053 (1) ◽  
pp. 012005
Author(s):  
I I Komarov ◽  
O V Zlyvko ◽  
A N Vegera ◽  
B A Makhmutov ◽  
I A Shcherbatov

Abstract Coal-fired steam turbine thermal power plants produce a large part of electricity. These power plants usually have low efficiency and high carbon dioxide emission. An application of combined cycle power plants with coal gasification equipped with carbon capture and storage systems may increase the efficiency and decrease the harmful emission. This paper describes investigation of the oxidizer type in the integrated gasification combined cycle combustion chamber and its influence upon the energy and environmental performance. The integrated gasification combined cycle and oxy-fuel combustion technology allow the carbon dioxide capture and storage losses 58% smaller than the traditional air combustion one. The IGCC with air combustion without and with carbon dioxide capture and storage has 53.54 and 46.61% and with oxy-fuel combustion has 34.94 and 32.67% net efficiency. Together with this the CO2 emission drops down from 89.9 to 10.6 gm/kWh. The integrated coal gasification combined cycle with air oxidizer has the best net efficiency.


Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2927
Author(s):  
Andrey Rogalev ◽  
Nikolay Rogalev ◽  
Vladimir Kindra ◽  
Ivan Komarov ◽  
Olga Zlyvko

The transition to oxy-fuel combustion power cycles is a prospective way to decrease carbon dioxide emissions into the atmosphere from the energy sector. To identify which technology has the highest efficiency and the lowest emission level, a thermodynamic analysis of the semiclosed oxy-fuel combustion combined cycle (SCOC-CC), the E-MATIANT cycle, and the Allam cycle was carried out. The modeling methodology has been described in detail, including the approaches to defining the working fluid properties, the mathematical models of the air separation unit, and the cooled gas turbine cycles’ calculation algorithms. The gas turbine inlet parameters were optimized using the developed modeling methodology for the three oxy-fuel combustion power cycles with CO2 recirculation in the inlet temperature at a range of 1000 to 1700 °C. The effect of the coolant flow precooling was evaluated. It was found that a decrease in the coolant temperature could lead to an increase of the net efficiency up to 3.2% for the SCOC-CC cycle and up to 0.8% for the E-MATIANT cycle. The final comparison showed that the Allam cycle’s net efficiency is 5.6% higher compared to the SCOC-CC cycle, and 11.5% higher compared with the E-MATIANT cycle.


Author(s):  
Michael O’Sullivan ◽  
Michael Gravatt ◽  
Joris Popineau ◽  
John O’Sullivan ◽  
Warren Mannington ◽  
...  

2022 ◽  
Vol 1 (15) ◽  
pp. 71-75
Author(s):  
Dmitriy Kononov

The strategy of low-carbon development of the economy and energy of Russia provides for the introduction of a fee (tax) for carbon dioxide emissions by power plants. This will seriously affect their prospective structure and lead to an increase in electricity prices. The expected neg-ative consequences for national and energy security are great. But serious and multilateral research is needed to properly assess these strategic threats


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