Experimental study into the influence of straw content in fuel on parameters of generator gas

Abstract

For the gasification of straw-containing fuel, a gas generator of a specific design is proposed, in which the combustion and recovery zones have the same diameter. A mixture of wood and straw pellets was used as fuel. It was found that when up to 40 % or less straw pellets were used in the fuel during 360 s of the gas generator operation, no deposits on the grate were observed. Studies have been conducted to assess the effect of the content of straw pellets in the fuel on the concentration and volume of CO in the gas, the total gas yield, the amount of gas produced per kilogram of fuel, and the duration of the proposed gas generator. The results of the study are represented by one-factor equations. A two-factor experiment was performed to determine the effect of the straw pellet content in the fuel on the dynamics of changes in the CO concentration in the gas during the gas generator operation. In each series of experiments, a portion of 2 kg of fuel was loaded, the operating time and CO content in the gas were recorded at regular intervals. Moreover, with each loading of the gas generator with fuel, the content of straw pellets in the fuel increased from 0 % to 100 % in increments of 20 %.It was found that for efficient gasification of straw-containing fuel without the formation of solid deposits, it is rational to add no more than 40 % of straw pellets to the fuel. When using 40 % straw in the equation with wood, the concentration and volume of CO produced increases by 25 %, but the specific gas yield from the fuel decreases by 5.3 %. Although, at 100 % content of straw pellets in the fuel, there is an increase in the CO concentration in the generator gas by 44.3 %, the volume of CO - by 40 %, the total output of gas produced decreases by 7.7 %. The duration of the gas generator operation (when loading 2 kg of fuel) increases by 2.8%. The increase in CO content when using 100 % straw content in the fuel compared to 100 % wood content indicates an increase in the calorific value of the resulting gas by 13-18 %.Therefore, it is rational to use the amount of straw in the fuel up to 100 %, although this requires the development of gas generator designs that will avoid the formation of stable deposits on the working surfaces.