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Title: Countercurrent fixed-bed gasification of biomass at laboratory scale

Abstract

A laboratory-scale countercurrent fixed-bed gasification plant has been designed and constructed to produce data for process modeling and to compare the gasification characteristics of several biomasses (beechwood, nutshells, olive husks, and grape residues). The composition of producer gas and spatial temperature profiles have been measured for biomass gasification at different air flow rates. The gas-heating value always attains a maximum as a function of this operating variable, associated with a decrease of the air-to-fuel ratio. Optical gasification conditions of wood and agricultural residues give rise to comparable gas-heating values, comprised in the range 5--5.5 MJ/Nm{sup 3} with 28--30% CO, 5--7% CO{sub 2}, 6--8% H{sub 2}, 1--2% CH{sub 4}, and small amounts of C{sub 2}- hydrocarbons (apart from nitrogen). However, gasification of agricultural residues is more difficult because of bed transport, partial ash sintering, nonuniform flow distribution, and the presence of a muddy phase in the effluents, so that proper pretreatments are needed for largescale applications.

Authors:
; ;  [1]
  1. Univ. degli Studi di Napoli Federico II (Italy). Dipt. di Ingegneria Chimica
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
680072
Resource Type:
Journal Article
Resource Relation:
Journal Name: Industrial and Engineering Chemistry Research; Journal Volume: 38; Journal Issue: 7; Other Information: PBD: Jul 1999
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; GAS GENERATORS; GASIFICATION; NUTS; OLIVES; GRAPES; AGRICULTURAL WASTES; WOOD; PRODUCER GAS; CHEMICAL COMPOSITION; CALORIFIC VALUE

Citation Formats

Di Blasi, C., Signorelli, G., and Portoricco, G.. Countercurrent fixed-bed gasification of biomass at laboratory scale. United States: N. p., 1999. Web. doi:10.1021/ie980753i.
Di Blasi, C., Signorelli, G., & Portoricco, G.. Countercurrent fixed-bed gasification of biomass at laboratory scale. United States. doi:10.1021/ie980753i.
Di Blasi, C., Signorelli, G., and Portoricco, G.. 1999. "Countercurrent fixed-bed gasification of biomass at laboratory scale". United States. doi:10.1021/ie980753i.
@article{osti_680072,
title = {Countercurrent fixed-bed gasification of biomass at laboratory scale},
author = {Di Blasi, C. and Signorelli, G. and Portoricco, G.},
abstractNote = {A laboratory-scale countercurrent fixed-bed gasification plant has been designed and constructed to produce data for process modeling and to compare the gasification characteristics of several biomasses (beechwood, nutshells, olive husks, and grape residues). The composition of producer gas and spatial temperature profiles have been measured for biomass gasification at different air flow rates. The gas-heating value always attains a maximum as a function of this operating variable, associated with a decrease of the air-to-fuel ratio. Optical gasification conditions of wood and agricultural residues give rise to comparable gas-heating values, comprised in the range 5--5.5 MJ/Nm{sup 3} with 28--30% CO, 5--7% CO{sub 2}, 6--8% H{sub 2}, 1--2% CH{sub 4}, and small amounts of C{sub 2}- hydrocarbons (apart from nitrogen). However, gasification of agricultural residues is more difficult because of bed transport, partial ash sintering, nonuniform flow distribution, and the presence of a muddy phase in the effluents, so that proper pretreatments are needed for largescale applications.},
doi = {10.1021/ie980753i},
journal = {Industrial and Engineering Chemistry Research},
number = 7,
volume = 38,
place = {United States},
year = 1999,
month = 7
}
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