The result is a method for the preparation of a slurry from wet biomass (organic waste, herbaceous plant-like material) that can be pumped into ( high pressure) reactors for an energy conversion process like supercritical gasification, if necessary via a heat exchanger.
Conversion process like supercritical gasification are of special interest for the utilization of the energy content of wet biomass because a drying step for the biomass is not necessary.
The pumping tests are carried out for two capacity ranges; Small feed capacity pumps, only for pilot scale testing and large scale pumps, used for carry out pumping tests. Plunger, piston pumps found the most suitable pumps to pressurize bioslurries with particle size up to 7,5 mm and DM-content of 20 %.
The process is tested on a pilot scale and, depending on the biomass, an energetically and financially interesting process route is developed to wash and to reduce the particle size of the biomass. The most interesting way to produce a pumpable slurry is reduction of the particles size by grinding. The maximum costs for the feedstock and the pretreatment are 3 euro/GJth of hydrogen. The cost of the slurry production fluctuates from 1.8 to 11.5 euro/GJth of hydrogen. Only a selected part of the available biomasses will be suitable as feedstock for supercritical gasification.