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Bayham, Samuel

Publications and source records attributed to Bayham, Samuel.

43 records · Page 3

Operating experience of a 50kWth methane chemical looping reactor

Chemical Looping Combustion (CLC) has the potential to efficiently capture CO2 from the combustion of fossil fuels at an affordable price. CLC is a process that produces a flue gas primarily consisting of CO2 and H2O. The CO2 can be easily separated and captured by condensing the H2O, similar to an oxy-fuel process. Although the process looks promising on paper, the challenge of making chemical looping a reality involves demonstrating that the process is technically feasible. To help achieve this goal, the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL), has constructed and tested a 50kWth chemical looping reactor (CLR). The general arrangement of the process consists of a bubbling fluidized bed fuel reactor and a fluidized bed/riser air reactor. This paper will describe the results from a hematite ore that has been tested during a week-long test campaign.

01 COAL, LIGNITE, AND PEAT↗

Coal Direct Chemical Looping Retrofit to Pulverized Coal Power Plants for In-Situ CO2 Capture

A novel Coal Direct Chemical Looping (CDCL) system is proposed to effectively capture CO2 from existing PC power plants. The work during the past three years has led to an oxygen carrier particle with satisfactory performance. Moreover, successful laboratory, bench scale, and integrated demonstrations have been performed. The proposed project further advanced the novel CDCL technology to sub-pilot scale (25 kWth). To be more specific, the following objectives attained in the proposed project are: 1. to further improve the oxygen carrying capacity as well as the sulfur/ash tolerance of the current (working) particle; 2. to demonstrate continuous CDCL operations in an integrated mode with > 99% coal (bituminous, subbituminous, and lignite) conversion as well as the production of high temperature exhaust gas stream that is suitable for steam generation in existing PC boilers; 3. to identify, via demonstrations, the fate of sulfur and NOx; 4. to conduct thorough techno-economic analysis that validates the technical and economical attractiveness of the CDCL system. The objectives outlined above were achieved through collaborative efforts among all the participants. CONSOL Energy Inc. performed the techno-economic analysis of the CDCL process. Shell/CRI was able to perform feasibility and economic studies on the large scale particle synthesis and provide composite particles for the sub-pilot scale testing. The experience of B&W (with boilers) and Air Products (with handling gases) assisted the retrofit system design as well as the demonstration unit operations. The experience gained from the sub-pilot scale demonstration of the Syngas Chemical Looping (SCL) process at OSU was able to ensure the successful handling of the solids. Phase 1 focused on studies to improve the current particle to better suit the CDCL operations. The optimum operating conditions for the reducer reactor such as the temperature, char gasification enhancer type, and flow rate were identified. The modifications of the existing bench scale reactor were completed in order to use it in the next phase of the project. In Phase II, the optimum looping medium was selected, and bench scale demonstrations were completed using them. Different types of coal char such as those obtained from bituminous, subbituminous, and lignite were tested. Modifications were made on the existing sub-pilot scale unit for coal injection. Phase III focused on integrated CDCL demonstration in the sub-pilot scale unit. A comprehensive ASPEN® simulations and economic analysis was completed by CONSOL t is expected that the CDCL process will be ready for further demonstrations in a scale up unit upon completion of the proposed project.

Zeng, Liang↗