Calibration of the Reacting Vessel of a Downdraft Gasifier for Temperature Optimization: Initial Validation

Abstract: To achieve a tar free syngas production, the design and process variables of a gasifier must be considered and calibrated for optimum performance. This has been a major challenge in most gasification operation establishing the operating temperature with sensors considering the operational environment and duration. The research work presents a simple but valid process for the initial determination and calibration of temperature which can be done for any type of gasifier. This experimental calibration was done to establish the operating conditions of a laboratory scale fixed bed, downdraft gasifier for the conversion of wood waste to gaseous fuel using air as a medium by monitoring product parameters. The temperature, bed material, air flow ratio, nature and composition of the pellets and the product of the operation were considered for various trials. High temperature was achieved by increasing the refractory material used at the reduction zone of the bed and introducing char as bed material thus ensuring that the pyrolytic char is reduced with little or no tar in the product gas.

Keywords: Calibration, Downdraft gasifier, Temperature, Operating conditions, waste conversion.