Method for Optimization of the Gasifier Recovery Zone Height

The article provides the results of experimental studies of the effect of air introduction into a gasifier, the fuel particle size, and the recovery zone height on a content of carbon monoxide in wood gas. The mathematical models of wood gas formation presented in the scientific research have uncertain boundary conditions. For adequate use of the mathematical models numerous hypotheses are needed. Therefore, it is essential to acquire experimental data in the actual range of gasifier operation parameters. The research of influence of the gasifier design and operation parameters on the concentration of carbon monoxide in wood gas was conducted in the laboratory using a specially developed plant. The plant consisted of a gasifier with adjustable height of recovery zone and centrifugal air blower with adjustable rate of air introduction into the gasifier. The downdraft gasifier with combined combustion and recovery zones was used. These zones had a diameter of 200 mm. The thermal power of the gas generator was 5 kW. Hardwood with different size range was used as the raw material. The results of the experimental study lead to the establishment of rational values of the recovery zone height that provide the maximum concentration of carbon monoxide at various values of the fuel particle sizes and introduction of air into the gasifier