The gasifier running with single biomass throughout the year
suffers with issues such as risk on transportation, non-availability
of a particular biomass throughout the year and incomplete utilisation
of various biomasses available in a region [19]. Therefore
blends of biomasses in a gasifier can improve the continuous and
steady operation of gasifiers in remote areas. An analytical model
developed to analyse the performance of saw-dust/cow-dung
mixture in a downdraft gasifier shows that the mixing of cow dung
would reduce the gas production rate and heating value, however,
having 40–50% cow dung in the mixture is technologically and economically
viable [20]. To the further extent of this approach, through
this paper, the performance of a 50 kWth downdraft gasifier has been
analysed with the blends of coconut shell–rubber seed shell. Equilibrium
modelling concept has been used in the theoretical studies.
Experiments were also conducted to investigate the effect of mixture
composition and equivalence ratio on the species concentration and
heating value of the producer gas.