Catalytic Indirectly Heated Gasification of Bagasse

Abstract

The catalytic indirectly heated gasification of bagasse was investigated in this study. The quality of the gaseous fuel was assessed using the total energy analysis of the gas, in which both heat content and total yields of the gas produced from the gasification of bagasse are analyzed at temperatures ranging from 700 to 1000°C. Untreated bagasse gasification was used as a baseline for the investigation of the effect of catalysts on the gasification process. The total energy analysis showed a significant improvement of gas quality due to increase of temperature and due to the use of alumina-zinc based catalysts at temperatures below 900°C. The presence of these catalysts in the gasification process affected the quality of the gases formed, mainly by increasing the hydrogen production, reduction of the gas dilution by carbon dioxide and a slightly higher production of carbon monoxide. Above 900°C, temperature dominates the gasification reaction mechanisms causing the catalysts to have little or no significant effect. Thermal cracking of tar is of major importance on the gasification process, as the tar yields reduce from 42.1 to 24.7% of the bagasse original weight with the increase of the gasifier temperature from 700 to 1000°C. However, the solid residue reduced only from 16 to 13.3%. Hence, the increase in the gaseous yields at high temperature appeared to be due to the gasification of tar with some contribution from secondary reactions involving char. The result was the production of a medium heat content gaseous fuel.

Systematics of renewable olefins from thermal cracking of canola oil

“…4 and 5 show the variation of yields versus temperature for olefins, paraffins, aromatics, PNA, FAME's, and coke. In the case of IKB's CO x we use simple separate representation of CO and CO 2 yields to reflect CCTL [28] and other experiments that show that CO 2 comes in a lower temperature but declines a higher temperature. On the other hand CO comes in at higher temperatures and increases further at higher temperatures.…”

The Production of Gaseous Biofuels Using Biomass Waste from Construction Sites in Recife, Brazil

“…The gasification experiments were carried out using a bench-scale gasifier (BSG), illustrated in Figure 1. This BSG in the experiments was designed by Peres [14] and implemented with monitoring equipment for operation at different gasification temperatures and residence times [34,35]. This BSG consisted of a 30-cm-long, two-inch-diameter, 304 stainless-steel seamless tube gasifier (1).…”

“…For gasification processes, the temperature range lies within 700 • C and 900 • C in oxygen-deprived environments, typically 25-35% of the stoichiometric ratio for complete combustion [10]. The gaseous fuels' main constituents are carbon monoxide (CO), carbon dioxide (CO 2 ), hydrogen (H 2 ), methane (CH 4 ), nitrogen (N 2 ), and hydrocarbons (HCs) [2,10,[12][13][14][15][16][17]. The lower calorific value of these gaseous fuels may vary from 4-13 MJ•m −3 depending on the gasifier temperature and type [10,[12][13][14][15][16][17].…”

“…The gaseous fuels' main constituents are carbon monoxide (CO), carbon dioxide (CO 2 ), hydrogen (H 2 ), methane (CH 4 ), nitrogen (N 2 ), and hydrocarbons (HCs) [2,10,[12][13][14][15][16][17]. The lower calorific value of these gaseous fuels may vary from 4-13 MJ•m −3 depending on the gasifier temperature and type [10,[12][13][14][15][16][17]. According to Sikarwar et al (2016), one of the most commonly used gasifiers is a fixed-bed gasifier (FXBG) that can exist as either an updraft (fuel enters from the top, gasifying agent enters from the bottom) or a downdraft gasifier (both fuel and gasifying agent enter from the top) [17].…”

“…According to Sikarwar et al (2016), one of the most commonly used gasifiers is a fixed-bed gasifier (FXBG) that can exist as either an updraft (fuel enters from the top, gasifying agent enters from the bottom) or a downdraft gasifier (both fuel and gasifying agent enter from the top) [17]. Gasification enables solid biomass to be used as fuel in internal combustion engines and gas turbine cycles, as well as to produce green liquid fuels [9,[11][12][13][14][15][16][17]. Kirubakaran et al reported that gasification is economical at all capacities from 5 kWe onward, and that the rate of gasification is affected by the size, shape, environment, moisture, and ash content of the feedstock, as well as waste flow (batch or continuous) and gasification temperature [18].…”