Quantitative real-time in situ measurement of gaseous K, KOH and KCl in a 140 kW entrained-flow biomass gasifierShow others and affiliations
2023 (English)In: Proceedings of the Combustion Institute, ISSN 1540-7489, E-ISSN 1873-2704, Vol. 39, no 1, p. 1337-1345Article in journal (Refereed) Published
Abstract [en]
Photofragmentation tunable diode laser absorption spectroscopy (PF-TDLAS) was used to simultaneously measure the concentrations of gas phase atomic potassium (K), potassium hydroxide (KOH) and potassium chloride (KCl) in the reactor core of a 140 kWth atmospheric entrained-flow gasifier (EFG). In two gasification experiments at air-to-fuel equivalence ratio of 0.5, the EFG was first run on forest residues (FR) and then on an 80/20 mixture of FR and wheat straw (FR/WS). Combustion at air-to-fuel equivalence ratio of 1.3 was investigated for comparison. A high K(g) absorbance was observed in gasification, requiring the photofragmentation signals from KOH(g) and KCl(g) to be recorded at a fixed detuning of 7.3 cm-1 from the center of the K(g) absorption profile. In combustion, the fragments recombined instantly after the UV pulse within around 10 μs, whereas in gasification, the K(g) fragment concentration first increased further for 30 μs after the UV pulse, before slowly decaying for up to hundreds of μs. According to 0D reaction kinetics simulations, this could be explained by a difference in recombination kinetics, which is dominated by oxygen reactions in combustion and by hydrogen reactions in gasification. The K species concentrations in the EFG were stable on average, but periodic short-term variations due to fuel feeding were observed, as well as a gradual increase in KOH(g) over the day as the reactor approached global equilibrium. A comparison of the average K species concentrations towards the end of each experiment showed a higher total K in the gas phase for FR/WS, with higher K(g) and KCl(g), but lower KOH(g), compared to the FR fuel. The measured values were in reasonable agreement with predictions by thermodynamic equilibrium calculations. © 2022 The Author(s).
Place, publisher, year, edition, pages
Elsevier Ltd , 2023. Vol. 39, no 1, p. 1337-1345
Keywords [en]
Biomass, Entrained-flow gasification, Photofragmentation, Potassium (K), Tunable diode laser absorption spectroscopy (TDLAS), Absorption spectroscopy, Combustion, Fuels, Gases, Gasification, Potassium hydroxide, Reaction kinetics, Semiconductor lasers, Entrained flow gasification, Entrained flow gasifiers, Equivalence ratios, Forest residue, Gas-phases, Potassium chloride, Tunable diode laser absorption spectroscopy, Chlorine compounds
National Category
Energy Engineering
Identifiers
URN: urn:nbn:se:ri:diva-61456DOI: 10.1016/j.proci.2022.07.180Scopus ID: 2-s2.0-85139508080OAI: oai:DiVA.org:ri-61456DiVA, id: diva2:1717148
Note
Funding details: 36160-1, 50470-1; Funding details: Energimyndigheten; Funding details: Kempestiftelserna, JCK-1316; Funding details: Horizon 2020, 637020; Funding text 1: The authors acknowledge financial support from the Swedish strategic research program Bio4Energy, the Kempe Foundations ( JCK-1316 ), and the Swedish Energy Agency through both the Swedish Gasification Centre and projects no. 50470-1 and 36160-1 . The fuels were received from a project which received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 637020 - Mobile Flip.
2022-12-072022-12-072024-05-17Bibliographically approved