Investigation of core-annular flow in an industrial scale circulating fluidized bed riser with electrical capacitance volume tomography (ECVT)

Weber, Justin M.; Bobek, Michael M.; Breault, Ronald W.; Mei, Joseph S.; Shadle, Lawrence J.

doi:10.1016/j.powtec.2017.12.094

Title: Investigation of core-annular flow in an industrial scale circulating fluidized bed riser with electrical capacitance volume tomography (ECVT)

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Abstract

There is a paucity of riser data for industrial scale units, particularly with regard to the solids fraction. This is especially true for detailed spatially distributed values. To alleviate this problem, NETL installed a 0.445 m tall electrical capacitance volume tomography (ECVT) sensor 9.66 m from the gas distributor of its industrial size (15.45 m high and 0.3 m diameter) circulating fluidized bed (CFB) cold model. A series of tests were conducted to investigate the gas-solid flow behavior using high density polyethylene (PPE) solids. Static electricity was successfully minimized using Larostat and humidification. Time averaged radial solid fractions profiles are presented and discussed. The time and spatially averaged solid fractions measured by the ECVT agree well with estimates from the pressure drop. The annular thickness was measured and found to increase with increases in the solids flow rate and decrease with increases in the gas velocity. Comparisons of the annular thickness and solids fraction as determined from the ECVT unit were compared to existing correlations. In conclusion, the average error ranged from 13% to 275% which is not surprising since the literature correlations were developed from data on much smaller units and for significantly different particles.

Authors:

Weber, Justin M. ^[1]; Bobek, Michael M. ^[2]; Breault, Ronald W. ^[1]; Mei, Joseph S. ^[1]; Shadle, Lawrence J. ^[1]

National Energy Technology Lab. (NETL), Morgantown, WV (United States)
Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)

Publication Date:: Thu Mar 01 00:00:00 EST 2018

Research Org.:: National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1461085

Resource Type:: Accepted Manuscript

Journal Name:: Powder Technology

Additional Journal Information:: Journal Volume: 327; Journal Issue: C; Journal ID: ISSN 0032-5910

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 42 ENGINEERING; Electrical capacitance; ECVT; ECT; Tomography; Circulating fluidized bed; CFB

Citation Formats


                    Weber, Justin M., Bobek, Michael M., Breault, Ronald W., Mei, Joseph S., and Shadle, Lawrence J. Investigation of core-annular flow in an industrial scale circulating fluidized bed riser with electrical capacitance volume tomography (ECVT).  United States: N. p., 2018. 
Web.  doi:10.1016/j.powtec.2017.12.094.

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                    Weber, Justin M., Bobek, Michael M., Breault, Ronald W., Mei, Joseph S., & Shadle, Lawrence J. Investigation of core-annular flow in an industrial scale circulating fluidized bed riser with electrical capacitance volume tomography (ECVT).  United States.  https://doi.org/10.1016/j.powtec.2017.12.094

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                    Weber, Justin M., Bobek, Michael M., Breault, Ronald W., Mei, Joseph S., and Shadle, Lawrence J. Thu .  
"Investigation of core-annular flow in an industrial scale circulating fluidized bed riser with electrical capacitance volume tomography (ECVT)".  United States.  https://doi.org/10.1016/j.powtec.2017.12.094.  https://www.osti.gov/servlets/purl/1461085.

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@article{osti_1461085,

  title        = {Investigation of core-annular flow in an industrial scale circulating fluidized bed riser with electrical capacitance volume tomography (ECVT)},

  author       = {Weber, Justin M. and Bobek, Michael M. and Breault, Ronald W. and Mei, Joseph S. and Shadle, Lawrence J.},

  abstractNote = {There is a paucity of riser data for industrial scale units, particularly with regard to the solids fraction. This is especially true for detailed spatially distributed values. To alleviate this problem, NETL installed a 0.445 m tall electrical capacitance volume tomography (ECVT) sensor 9.66 m from the gas distributor of its industrial size (15.45 m high and 0.3 m diameter) circulating fluidized bed (CFB) cold model. A series of tests were conducted to investigate the gas-solid flow behavior using high density polyethylene (PPE) solids. Static electricity was successfully minimized using Larostat and humidification. Time averaged radial solid fractions profiles are presented and discussed. The time and spatially averaged solid fractions measured by the ECVT agree well with estimates from the pressure drop. The annular thickness was measured and found to increase with increases in the solids flow rate and decrease with increases in the gas velocity. Comparisons of the annular thickness and solids fraction as determined from the ECVT unit were compared to existing correlations. In conclusion, the average error ranged from 13% to 275% which is not surprising since the literature correlations were developed from data on much smaller units and for significantly different particles.},

  doi          = {10.1016/j.powtec.2017.12.094},

  journal      = {Powder Technology},

  number       = C,

  volume       = 327,

  place        = {United States},

  year         = {Thu Mar 01 00:00:00 EST 2018},

  month        = {Thu Mar 01 00:00:00 EST 2018}

}

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