Potentials of hydrogen production through gasification of industrial waste
Augsburg, 21 June 2022
bifa Umweltinstitut GmbH publishes current study results at the Bavarian Waste and Landfill Days in Augsburg with the new publication of bifa text no. 72.
Can hydrogen be produced from commercial waste if it is not recycled? The process suitable for this is gasification - a thermochemical process in which a carbon-containing feedstock is converted into a product gas at temperatures between 500 °C and 1,200 °C. The potential of such hydrogen production is being explored in the currently completed bifa study.
In the currently completed bifa study, the potential of such hydrogen production is being explored. Suitable waste streams and quantities in Bavaria, gasification technologies, development status, greenhouse gas effects as well as challenges and opportunities of implementation were comprehensively analysed. The project, in which bifa Umweltinstitut GmbH cooperated with KUMAS Kompetenzzentrum Umwelt e. V., was funded by the Bavarian State Ministry for the Environment and Consumer Protection.
On the way to greenhouse gas neutrality, non-fossil hydrogen is an important energy carrier and chemical raw material. However, the availability of renewable electricity for the production of hydrogen by electrolysis is limited. The thermochemical production of hydrogen opens up an alternative, additional production path.
Fixed-bed, circulating and stationary fluidised bed, entrained flow as well as grate and rotary kiln gasifiers can be considered for the process, but also combinations of these. In addition, feedstock preparation, gas treatment and hydrogen separation are required. Depending on the plant technology, 40 - 60 % of the energy contained in the feedstock is converted into hydrogen. For processed waste, hydrogen yields of about 100 kg per tonne of feedstock can be assumed. Waste streams that appear to be suitable are, in particular, fractions rich in plastics and wood.
Realised plant concepts were researched, characterised and evaluated internationally. New developments were also explored. Few plant concepts were developed for waste and currently have reliable industrial operating experience. Other processes are in use for biomass and can be adapted to waste if necessary. Commercial viability of gasification of industrial waste to hydrogen is within the realm of the realistic.
The CO2 footprint of a gasification process that produces hydrogen was investigated in comparison to a waste incineration process with downstream electrolysis. The hydrogen yield is the main factor influencing the total emissions. It is higher with gasification than with waste incineration followed by electrolysis.
The main challenge for implementing the technology is the as yet unproven economic feasibility under local boundary conditions. A successful demonstration plant as a reference would be a valuable milestone. Legal issues also need to be clarified. Important opportunities lie in the climate protection potential.
The bifa text no. 72: "Potentials of hydrogen production by gasification of commercial waste" is now available free of charge at www.bifa.de.