Oxy-fuel Combustion already Commercial --- Hot Topic Hour on Thursday January 10, 2013 at 10:00 am CST

A good mix of research and commercial intelligence was delivered by a top notch group of speakers yesterday. We were introduced to pressurized oxycombustion which eliminates the need for compression in the turbine. Oxy-fuel combustion may offer the fossil-fueled power producing utility industry the solution to a number of significant problems – mandated GHG reduction, regulations requiring near zero emissions of a growing number of pollutants, high capital costs of flue gas cleaning equipment and increasing fuel and operating costs. When used in a pulverized coal-fired boiler, the oxy-fuel process produces a concentrated stream of CO₂, which may allow the CO₂ to be captured for use in enhanced oil recovery (EOR) projects or underground storage in a more cost effective manner compared to post-combustion capture of CO₂ from an air-fired boiler. In addition, when the process is optimized, it could significantly reduce the emissions of all regulated pollutants from the stack gases.

The oxy-fuel technology is less complex than other clean coal technologies and the process can be retrofit to existing coal-fired power plants or incorporated into new power plant designs. In either case, the adoption of oxy-fuel combustion could be more cost effective and require less capital than a conventional coal-fired power plant with all of the extra air pollution control equipment required to meet current and future emission limits. Also if oxy-fuel combustion is combined with circulating fluidized bed technology (CFB), it should allow the combustion of a wide range of fuels including co-firing of all forms of biomass, sludge and waste with coal or as the only fuel.

 Chendhil Periasamy at Air Liquide Delaware Research and Technology Center, presented an “Update on Oxy-fuel Combustion System Design for Natural Gas-fired Power Plants with Flue Gas Recirculation.” He described the latest developments in oxy-fuel combustion system design for power plants firing natural gas. Key design considerations for burner and combustion systems of the boiler island were discussed, along with the role of the flue gas recirculation ratio in reducing NO_x. The use of computer modeling in supporting burner design and pilot scale testing was explained.

Leonard Devanna, Executive Vice President Clean Energy Systems, displayed the program which will make oxy fuel commercial in the very near term. The TriGen™ Oxy-Fuel cycle includes CO₂ recovery and is already being discussed for projects where greenhouse gases are a concern and there is need for EOR.  In California unreliable solar and wind dictate the use of peaking gas turbines, except that they generate large amounts of CO₂ per mhr and also generate NO_x. Since California has lots of needs for enhanced oil recovery, it is very attractive to consider oxycombustion and CO₂ sequestration.

Richard Axelbaum, Ph.D., Director of the Consortium for Clean Coal Utilization and Professor of Energy, Environmental and Chemical Engineering at Washington University in St. Louis, presented “Staged Pressurized Oxy-Combustion for Next Generation Carbon Capture and Storage.” His talk described a novel system for carbon capture and storage (CCS) wherein coal and oxygen are combusted in stages under pressure. This approach increases plant efficiency and is expected to reduce the cost of electricity as it addresses a number of the challenges associated with traditional oxy-combustion for carbon capture.

Robert (Bob) Marrs, ThermoEnergy Power Systems, LLC explained the advantages of POXC™. (pressurized Oxy-Combustion)

• POXC™ can be retrofitted into existing plants utilizing existing infrastructure of steam cycle, coal handling and transmission lines.
• POXC™ plants can achieve net efficiency >35 percent.
• LCOE < 1.3X conventional PC. (Levelized Energy Cost)
• Proven ability to utilize low rank coals.
• Virtually no emissions; flyash eliminated and vitrified slag classified as inert in the EU.
• Dramatically improved water profile.
• Captures CO₂ at pressure requiring minimal CPU treatment.

Progress has been sufficient at U.S. and Italian power plants to move to a 50 MW thermal size. In the ensuing discussion there was agreement that there are advantages in terms of energy saving and size of the equipment, but the questions centered around whether the increased cost of materials would offset some of the other cost advantages.

Bios, Abstracts and Photos can be seen at:
BIOS, ABSTRACTS, PHOTOS - 1-10-13.htm

The individual presentations are as follows:

• Update on Oxy-fuel Combustion - Webinar - Hot Topic Hour on Thursday January 10, 2013

   

• Pressurized Oxy-Combustion by Robert Marrs, Thermo Energy Power Systems (United Power Alliance) - Hot Topic Hour January 10, 2013
• Update on Oxy-fuel Combustion by Leonard Devanna, Clean Energy Systems - Hot Topic Hour January 10, 2013

• Update on Oxy-fuel Combustion System Design for Natural Gas-fired Power Plants by Chendhil Periasamy, Air Liquide - Hot Topic Hour January 10, 2013.

• Staged, Pressurized Oxy-Combustion by Richard Axelbaum, Washington University in St. Louis - Hot Topic Hour January 10, 2013.