Gasification of crop residue sheds in a tubular downdraft gasifier

Abstract

A set of biomass materials was gasified in a 6 in diameter 150 centimeter long open-top gasifier in a batch mode. Among the biomass materials tested successfully were corn cobs , hammermilled corn cobs , ordinary rice hulls , bagasse fibers , wood shavings , and cut water hyacinth stems. A number of other biomass materials were either unsuccessfully gasified or were gasified with difficulty mainly due to the presence of excessive biomass fines. Such as bagasse as received from sugar mills, shredded rice hull, sawdust, carbonized round rice hull pellets, and corn cob fines. With many such low bulk density biomass materials fuel cavitation in the batch gasifier was found to be a problem for several types of fuels. The open top gasifier operated at temperature levels which were generally low in the reaction zones and this was believed to cause gas calorific content somewhat lower than gas calorific contents expected from ordinary closed-top tuyered charcoal gasifiers. The range of calorific content obtained in these set of experiment ranges from 280.30-1363.19 kcal/scm.