From Waste-to-Energy (WTE) to waste to hydrogen production is an interesting and attractive development taking place in the field of waste to value. Hydrogen is high energy content (33.3 kWh/kg) fuel producing no carbon emissions on incineration. The production and use of hydrogen as fuel support the carbon neutral energy strategies.
Non-recyclable Municipal Solid Waste (MSW) contains significant fraction of biodegradable/biomass-based waste components such as food waste, other bio-waste fraction (wood, yard/garden waste, grass, plant branches etc.) and paper/card (produced from wood). The mentioned biodegradable fraction can be upto 50 wt % of MSW and in some places even more. The bio fraction of MSW is said to be renewable source of energy as it is considered biomass based raw material.
Gasification of non-recyclable MSW (after pre-treatment i.e. sorting of recyclable and shredding to required particle size) is seen as a potentially efficient route producing hydrogen rich syngas which is further treated to produce hydrogen and separating carbon dioxide as process by-product. Using steam or mixture of steam and air/oxygen as gasifying medium maybe favourable to increase hydrogen content in syngas. Also, moisture content of waste itself maybe favourable in producing hydrogen rich syngas. The product gas produced as result of waste gasification/steam gasification is further processed through number gas purification techniques such as filtration, water-gas shift reaction (CO + H2O à CO2 + H2), gas cleaning (scrubbing, absorption) and hydrogen separation (membrane separation) producing hydrogen as process product and carbon dioxide as by-product. A schematic diagram of waste to hydrogen production based on steam gasification route is shown in the Figure below.
Figure: Waste to hydrogen production – concept schematic
The above-mentioned waste to hydrogen production route may potentially offer better economical (in terms of CAPEX and OPEX) option compared to hydrogen production in which first electricity is produced in a separate plant/process which is then provided to electrolysis process to produce hydrogen. As in the mentioned route of waste gasification process to produce hydrogen, electrolysis process is not needed. Hydrogen produced can be used as transportation fuel and carbon dioxide produced as process by-product can be stored or used as raw material for certain chemical or fuel synthesis processes. The overall process produces hydrogen as fuel and reduces carbon emissions.
Chemitec Consulting Oy offers its services in the field of green and blue hydrogen production in terms of performing due-diligence, techno-economic evaluation, pre-feasibility study and basic design of industrial scale green and blue hydrogen production processes.
For more information on Chemitec’s Waste to Value related services, please contact with Luis Rudolphy, CEO luis.rudolphy@chemitec.fi +358 40 1972323 and Tiina Piira, COO tiina.piira@chemitec.fi +358 50 5852627.