Experimental investigation of a dual stage ignition biomass downdraft gasifier for deriving the engine quality gas

The dual stage ignition biomass downdraft gasifier is the promising technology for huge tar reduction, based on two experimental approaches such as single stage and dual stage ignition. The whole unit has been tested with gradually increasing electric resistive load from 15.24 kW to 38.86 kW with a useful energy output of nearly 86.41 %. In single stage ignition approach, the hot air is only supplied at the com-bustion zone through a nozzle, while the two-stage ignition approach has supply of the premixed gas (hot air plus producer gas) at the pyrolysis zone for partial combustion. In dual stage ignition, the enhanced quality of producer gas comes from 56 % combustible gas with the HHV of 6.415 MJ/Nm3, while the bio-mass consumption rate is 59 kg/h at the maximum load with grate temperature of 1310-1360 degrees C. The tar content after gas cooling and cleaning unit is 8 mg/Nm3 with 15 % improvement in efficiency.(c) 2022 THE AUTHOR. Published by Elsevier BV on behalf of Faculty of Engineering, Ain Shams University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The dual stage ignition biomass downdraft gasifier is a promising technology for reducing tar production, which is tested with single stage and dual stage ignition methods. The unit is tested with gradually increasing electric resistive load and achieves a useful energy output of nearly 86.41%. The dual stage ignition approach improves the quality of producer gas, with 56% combustible gas content and higher heating value. The tar content is reduced to 8 mg/Nm3 with a 15% improvement in efficiency after gas cooling and cleaning unit.