JV Task - 129 Advanced Conversion Test - Bulgarian Lignite

PDF Version Also Available for Download.

Description

The objectives of this Energy & Environmental Research Center (EERC) project were to evaluate Bulgarian lignite performance under both fluid-bed combustion and gasification conditions and provide a recommendation as to which technology would be the most technically feasible for the particular feedstock and also identify any potential operating issues (such as bed agglomeration, etc.) that may limit the applicability of a potential coal conversion technology. Gasification tests were run at the EERC in the 100-400-kg/hr transport reactor development unit (TRDU) on a 50-tonne sample of lignite supplied by the Bulgarian Lignite Power Project. The quality of the test sample was ... continued below

Creation Information

Swanson, Michael; Sondreal, Everett; Laudal, Daniel; Hajicek, Douglas; Henderson, Ann & Pavlish, Brandon March 27, 2009.

Context

This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this report can be viewed below.

Who

People and organizations associated with either the creation of this report or its content.

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this report. Follow the links below to find similar items on the Digital Library.

Description

The objectives of this Energy & Environmental Research Center (EERC) project were to evaluate Bulgarian lignite performance under both fluid-bed combustion and gasification conditions and provide a recommendation as to which technology would be the most technically feasible for the particular feedstock and also identify any potential operating issues (such as bed agglomeration, etc.) that may limit the applicability of a potential coal conversion technology. Gasification tests were run at the EERC in the 100-400-kg/hr transport reactor development unit (TRDU) on a 50-tonne sample of lignite supplied by the Bulgarian Lignite Power Project. The quality of the test sample was inferior to any coal previously tested in this unit, containing 50% ash at 26.7% moisture and having a higher heating value of 5043 kJ/kg after partial drying in preparation for testing. The tentative conclusion reached on the basis of tests in the TRDU is that oxygen-blown gasification of this high-ash Bulgarian lignite sample using the Kellogg, Brown, and Root (KBR) transport gasifier technology would not provide a syngas suitable for directly firing a gas turbine. After correcting for test conditions specific to the pilot-scale TRDU, including an unavoidably high heat loss and nitrogen dilution by transport air, the best-case heating value for oxygen-blown operation was estimated to be 3316 kJ/m{sup 3} for a commercial KRB transport gasifier. This heating value is about 80% of the minimum required for firing a gas turbine. Removing 50% of the carbon dioxide from the syngas would increase the heating value to 4583 kJ/m{sup 3}, i.e., to about 110% of the minimum requirement, and 95% removal would provide a heating value of 7080 kJ/m{sup 3}. Supplemental firing of natural gas would also allow the integrated gasification combined cycle (IGCC) technology to be utilized without having to remove CO{sub 2}. If removal of all nitrogen from the input gas streams such as the coal transport air were achieved, a heating value very close to that needed to fire a gas turbine would be achieved; however, some operational issues associated with utilizing recycled syngas or carbon dioxide as the transport gas would also have to be resolved. Use of a coal with a quality similar to the core samples provided earlier in the test program would also improve the gasifier performance. Low cold-gas efficiencies on the order of 20% calculated for oxygen-blown tests resulted in part from specific difficulties experienced in trying to operate the pilot-scale TRDU on this very high-ash lignite. These low levels of efficiency are not believed to be representative of what could be achieved in a commercial KRB transport gasifier. Combustion tests were also performed in the EERC's circulating fluidized-bed combustor (CFBC) to evaluate this alternative technology for use of this fuel. It was demonstrated that this fuel does have sufficient heating value to sustain combustion, even without coal drying; however, it will be challenging to economically extract sufficient energy for the generation of steam for electrical generation. The boiler efficiency for the dried coal was 73.5% at 85% sulfur capture (21.4% moisture) compared to 55.3% at 85% sulfur capture (40% moisture). Improved boiler efficiencies for this coal will be possible operating a system more specifically designed to maximize heat extraction from the ash streams for this high-ash fuel. Drying of the coal to approximately 25% moisture probably would be recommended for either power system. Fuel moisture also has a large impact on fuel feedability. Pressurized gasifiers generally like drier fuels than systems operating at ambient pressures. The commercially recommended feedstock moisture for a pressurized transport reactor gasifier is 25% moisture. Maximum moisture content for a CFB system could be approximately 40% moisture as has been demonstrated on the Alstom CFB operating on Mississippi lignite. A preliminary economic evaluation for CO{sub 2} was performed on the alternatives of (1) precombustion separation of CO{sub 2} in an IGCC using the KBR transport gasifier and (2) postcombustion CO{sub 2} capture using a CFBC. It appears that the capture of CO{sub 2} from the high-pressure IGCC precombustion system would be less costly than from the low-pressure postcombustion CFBC system by a factor of 1.5, although the cost difference is not directly comparable because of the model input being limited to a higher coal quality than the Bulgarian lignite. While the decision to pursue precombustion removal of carbon dioxide has been technically proven with the Rectisol{reg_sign} and Selexol{trademark} processes, General Electric and Siemens have not sold any gas turbine systems running on the high-hydrogen syngas. They have successfully demonstrated a gas turbine on syngases containing up to 95% hydrogen. The technological hurdles should not be too difficult given this experience in the gas turbine industry.

Language

Item Type

Identifier

Unique identifying numbers for this report in the Digital Library or other systems.

  • Report No.: None
  • Grant Number: FC26-98FT40321
  • DOI: 10.2172/990807 | External Link
  • Office of Scientific & Technical Information Report Number: 990807
  • Archival Resource Key: ark:/67531/metadc1014475

Collections

This report is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • March 27, 2009

Added to The UNT Digital Library

  • Oct. 14, 2017, 8:36 a.m.

Description Last Updated

  • Dec. 18, 2017, 6:12 p.m.

Usage Statistics

When was this report last used?

Congratulations! It looks like you are the first person to view this item online.

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Swanson, Michael; Sondreal, Everett; Laudal, Daniel; Hajicek, Douglas; Henderson, Ann & Pavlish, Brandon. JV Task - 129 Advanced Conversion Test - Bulgarian Lignite, report, March 27, 2009; United States. (digital.library.unt.edu/ark:/67531/metadc1014475/: accessed July 19, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.