Production of sustainable methanol from aquatic biomass via thermal conversion route

Abstract

Energy security is considered a basic need for the community. The development of a non-competing energy source is necessary to maintain harmony when fulfilling energy and food needs. Aquatic biomass such as algae is a promising sustainable energy source as it can be cultivated in the sea or pond which does not require productive land. By using thermal reaction, algae can be converted into methanol via gasification followed by hydrogenation reactions. The key challenge of algae utilization lies in the high moisture content. This work presents an understanding of the role of moisture on the algae for methanol production. Although moisture content has a negative impact on the syngas quality, the methanol production does not change with increasing moisture content. Under the optimum condition, the algae-to-methanol route converts ∼45% of the total energy input into energy in the form of methanol. The production of one-ton methanol from algae with 10 wt% moisture requires algae (2.7 ton), oxygen (0.9 ton), boiler feed water (1.5 ton), thermal energy (12.1 GJ) and electricity (0.7 MWh). The present work provides a clear understanding of the potential of aquatic biomass for methanol production, leading to further development to achieve a feasible algae-to-methanol route.