Bio-CLC Pilot Scale Experiments Combined with CFD Simulations: How To Improve the Performance by Better Design?

Juho Peltola (Corresponding author), Toni Pikkarainen, Timo Niemi

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsProfessional

    Abstract

    Mitigation of climate change by stabilizing the global mean temperature
    rise well below 2°C from the pre-industrial temperature level requires implementation of negative emission technologies (NETs). One of the most promising NETs is chemical looping combustion of biomass (bio-CLC). Biomass has the capability of withdrawing and storing atmospheric CO2 during growing. CO2 released from biomass during combustion can be captured and stored permanently underground, thus resulting net-negative CO2 emissions to the atmosphere. Recently bio-CLC has been tested in pilot and laboratory scale. Results with different solid biomass types and oxygen carriers has been published. The most important and common operational challenge has been deficient mixing and contact between oxygen transported by oxygen carriers
    and volatiles released from biomass. This leads to insufficient combustion of gaseous species and high oxygen consumption in subsequent oxygen polishing unit. Also high concentrations of tars has been observed increasing the risk of operational problems. In this paper, pilot scale experimental results of bio-CLC with results of computational fluid dynamics (CFD) simulations of mixing are presented. Experimental tests were carried out with wood based pellets and wood char using ilmenite (iron based) and braunite (manganese based) as oxygen carriers. CFD simulations were used to study volatile gas by-pass differences observed in the experiment. The fluidized oxygen carrier bed was simulated using two-phase Euler-Euler approach. Fuel particles were
    included in the simulation as Lagrangian particles with models for evaporation,
    pyrolysis and gasification. CFD simulations were carried out with different fuels and particle size distributions. Simulation results are used to study the distribution of volatile release from different fuel particles and contact between the oxygen carriers and volatiles. Based on the results, an alternative reactor configuration that could decrease volatile gas bypass is simulated to illustrate how CFD simulations can be beneficial in design of pilot and large scale CLC systems, especially in fuel reactor and fuel feeding design.
    Original languageEnglish
    Title of host publication5th International Conference on Chemical Looping
    Number of pages19
    Publication statusPublished - 2018
    MoE publication typeD3 Professional conference proceedings
    Event5th International Conference on Chemical Looping - Utah, United States
    Duration: 24 Sep 201827 Sep 2018

    Conference

    Conference5th International Conference on Chemical Looping
    Country/TerritoryUnited States
    CityUtah
    Period24/09/1827/09/18

    Fingerprint

    Dive into the research topics of 'Bio-CLC Pilot Scale Experiments Combined with CFD Simulations: How To Improve the Performance by Better Design?'. Together they form a unique fingerprint.

    Cite this