Infinity Turbine LLC


Publication Title | GENERATION

Organic Rankine Cycle

Waste Heat to Power ORC search was updated real-time via Filemaker on:

Waste Heat to Power ORC | Return to Search List

Search Completed | Title | GENERATION
Original File Name Searched: 01_02_2016_020.pdf | Google It | Yahoo | Bing



Page Number: 001
Previous Page View | Next Page View

Text | GENERATION | 001



GENERATION

Fig. 4: Possible directly heated SCCD cycle (NTEL [2]).

understanding of how fossil based thermal systems may best be integrated with recuperated closed Brayton cycles and identify component and boiler technology requirements and integration issues for future development and risk reduction [4].

New installations

New installations allow the design of a system specifically tailored for the S-CO2 cycle. Proposed systems based on oxy- combustion and direct heating offer the possibility of integrated carbon capture together with the use of a pressured fluidised bed combustion system (PFBC). A proposed system is shown in Fig. 5.

Existing coal-fired systems

The possibility of using existing boiler plant for S-CO2 based systems has been investigated, but there does not seem to be any specific project aimed at achieving replacement of the steam cycle with an S-CO2 cycle in an existing installation. The process does offer advantages where lifetime extension of existing steam plant has to be considered.

Issues under investigation include modification of existing furnaces/boiler plant to interface with S-CO2 power blocks. It anticipates that projects will advance indirect fossil-fired utility-scale S-CO2 plants by addressing challenges facing the tight integration of the secondary and thermal systems with the S-CO2 power block [1].

ICGG bottoming cycles

Replacing the steam turbine in a GCGT running in an ICG system with a S-CO2 plant is an easier option as the only change involved would be the heat exchanger, and the system is likely to be lower than utility scale, which offers short term possibilities. This option has been considered in a number of proposed systems [4].

References

[1] Wilkes: “Fundamentals of Supercritical CO2”, ASME Turbo Expo 2014, Düsseldorf, Germany, June, 2014.

[2] NETL: “Technology Development for Supercritical Carbon Dioxide (S-CO2) Based Power Cycles”, www.netl.doe.gov/research/ coal/energy-systems/turbines/supercritical- co2-power-cycles

[3] M Persichilli: “Supercritical CO2 Power Cycle Developments and Commercialization: Why S-CO2 can Displace Steam”, Power-Gen India & Central Asia, 2012.

[4] NETL: “Absorption/Desorption Based High Efficiency Supercritical Carbon Dioxide Power Cycles”

[5] USA DoE: “Supercritical CO2 Tech Team”, http://energy.gov/supercritical-co2-tech-team [6] Echogen: “Supercritical CO2 power cycle developments and commercialisation”,

http://goo.gl/561M15

Send your comments to: energize@ee.co.za 

Fig. 5: Proposed PFBC S-CO2 direct heating system (NETL [4]).

materials, fabrication, channel geometry, fouling, corrosion and maintenance. Long- term corrosion and materials testing across all components also continue to be active areas of research.

Application to coal-fired stations

The cycle is applicable to multiple coal- based platforms (air and oxygen-fired, PC, CFB, PFBC). Coal combustor modifications are needed to match the temperature- enthalpy profile of S-CO cycles of interest [2]. 2

Current development is based on concept demonstration with machines of the order of 10 MWe, and the challenge facing the industry is upscaling to utility- sized plant. Components are radically different from those used in steam plants, but are considered to be well within the

capabilities of existing engineering and manufacturing processes. The increase in efficiency effectively offsets the losses of energy used for CCS where carbon capture is a requirement. This is seen as solution to the CCS energy problem, and makes the S-CO2 an attractive consideration.

Several projects are presently underway worldwide, to investigate the possibility of integrating existing coal based thermal systems with S-CO2 power blocks. In addition the application of S-CO2 to new coal-fired stations is also well advanced. These investigations are being used to assess the impact of thermal integration on plant performance and identify current technology gaps when integrating fossil-based thermal systems with S-CO2 power blocks. This will extend current

energize - February 2016 - Page 18

Image | GENERATION



generation
Waste Heat to Power - ORC - - Waste Heat to Power System - Go to website

Search Engine Contact: greg@infinityturbine.com