In order to enhance the operation stability of biomass
co-gasification in entrained flow gasifier, based on an
equilibrium RGibbs reactor model, 02/fuel mass flow ratio maps
of dry feed gasifier and slurry feed gasifier with oxygen as agent
have been built and the performances of co-gasification have
been evaluated. The basic conditions are (1) wood, straw and
sludge are selected as three types of biomass; (2) 5% to 20% of
coal is replaced by biomass in weight; (3) the biomass moisture
content changes from 5% to 30% in weight. 02 mass flow ratio
has been controlled to maintain the gasifier's operation at
1350°C in different cases. The product gases compositions and
LHV of gases change with the biomass replacing ratio and the
biomass moisture content. The results show that co-gasification
performances decrease more when the ratio of biomass replacing
coal and the biomass moisture content increase simultaneously
and it is necessary to modify 02/fuel mass flow ratio greatly to
maintain the stable operation temperature.