Title:
Effects of Rice Straw Char on the Nascent Tar Removal in a Two-Stage Reactor
Author(s):
Zhang, Y.L., Luo, Y.H., Wu, W.G., Su, Y., Zhao, S.H., Wang, Y.
Document(s):
Paper
Abstract:
The two¬stage downdraft gasifier is a potential type of gasifier, which is suitable for distributed power system of biomass gasification and with merits of low tar content in syngas. In order to investigate the effects of rice straw char bed on the nascent tar removal, a lab¬scale two stage hot rod reactor was constructed. The nascent tar was produced in the first stage by pyrolysis of rice straw at 500°C. With the consistent input nascent tar, both the thermal cracking (without char bed) and char bed conditions were carried out in the second stage to remove the nascent tar with temperature ranges of 700¬1000°C. The rice straw char can effectively eliminate the PAHs (polycyclic aromatic hydrocarbons) and a high tar conversion efficiency of 95.884% at 900°C was obtained. Five typical tar species, including benzene, toluene, styrene, phenol and naphthalene, were quantitatively analyzed under varied conditions with or without the char bed. The water washed rice straw char and the char added with the K2CO3 powders were selected to be char bed of the comparative conditions to study the role of the alkali metal in the process of catalytic decomposition reactions of the nascent tar.
Keywords:
two-stage reactor, nascent tar, rice straw char, removal, alkali metal
Topic:
R&D on Biomass Conversion Technologies for Heating, Electricity and Chemicals
Subtopic:
Gasification for synthesis gas production
Event:
20th European Biomass Conference and Exhibition
Session:
2BV.2.38
Pages:
1104 - 1111
ISBN:
978-88-89407-54-7
Paper DOI:
10.5071/20thEUBCE2012-2BV.2.38
Price:
FREE
