Chemical Engineering Transactions (May 2019)
Methanol Production from Biomass Gasification: Techno-economic Assessment of Different Feedstocks
Abstract
This work presents an updated techno-economic assessment of methanol production, considering an entrained flow gasifier with different second generation biomasses. Computer simulations were performed with the aid of a gasification simulator GasDS and with commercial process simulator Aspen HYSYS. A method was proposed to determine biomass composition in terms of cellulose, hemicellulose and three surrogate compounds that account for the most abundant monomers that compose lignin chains; the lower heat value (LHV) relative error was not bigger than 10%. The kinetic model deriving from this biomass characterization (composition) is not sufficiently accurate to describe biomass gasification; this is due to unrealistically small residence times and the (not modelled) catalytic effect of molten slag. Biomass gasification output is efficiently estimated by using chemical equilibrium. At current methanol market price (350 €/t) the process is economically unfeasible at the current plant capacity of 100 MW LHV biomass input (production costs vary between 360 and 440 €/t).