Biorefineries Technical Centre
In the DBFZ’s Biorefineries Technical Centre, essential process steps for the conversion of (aqueous) biomass fows into solid, liquid and gaseous bioenergy carriers as well as basic chemicals are investigated and further developed. A wide range of test benches are available for research tasks and service contracts requiring the investigation of hydrothermal processes (HTC/HTV), biomass gasifcation, gas purifcation and catalytic synthesis as well as various processing technologies.
For the hydrothermal laboratory tests, three batch reactors (2x 500ml, 1x 10L), a continuous tube reactor and a two-stage, continuous plant are used. In addition to the screening of a wide variety of biomasses, extensive tests are carried out to determine the dependence of the yield and composition of the products on the reaction parameters. The liquid and solid (intermediate) products are examined with regard to their chemical composition and their fuel properties in the analytical laboratory of the DBFZ.
An entrained-fow and a fxed-bed gasifer are available for the investigation of biomass gasifcation. In the entrained-fow gasifer, biomass with particle diameters below 1mm is converted into a synthesis gas with low tar content at temperatures of up to 1,200°C and at atmospheric pressure, using air, steam and oxygen as gasifers. The fxed-bed gasifer is designed for temperatures up to 1,050°C, pressures up to 20 bars and variably adjustable mixtures of oxygen, nitrogen, air, water vapour and CO2 as gasifcation agents. In addition to gravimetric monitoring of the fxed bed over time, temperatures and gas compositions can be measured in situ along the length of the bed. Two different gas purifcation systems complete the gasifcation test rigs. In addition to a heatable three-chamber system for different sorbents, a small-scale mobile pilot plant is available for the two-stage hot deaeration of product gases.
Four different fxed-bed reactors are available to investigate the catalytic conversion of synthesis gas into fuels and basic chemicals such as methane (SNG) and short-chain alkenes. All reactors can be operated with product gas recirculation while two are fully automated. The aim is to investigate the dynamic reactor behaviour and the product gas composition with fluctuating synthesis gas qualities and flow rates (see power-to-gas). Due to the wide temperature and pressure window of the plants (p ≤ 60 bar, T ≤ 850 °C), different reactor concepts and operating conditions as well as classic and innovative catalysts can be compared directly with one another. In addition to the reactant gases H2, CO and CO2, water vapour and chemical pollutants (e. g. H2S for deactivation studies) can be directed into the reactor system to investigate their influence on conversion and selectivity.
With the aid of a decanter test stand, continuous two-phase separation of product fows is also possible below 100Lh-1. The solid-liquid separation is supplemented by a hydraulic hot drainage system for suspensions rich in solids. It is suitable for highly water-binding substances and offers the advantage of being able to drain hot intermediate streams directly without upstream cooling. The membrane fltration plant can be used for investigations in the felds of micro-, ultra- and nanofltration as well as in the feld of reverse osmosis. It enables membrane screening in wide pressure, temperature and pH ranges. Preparative HPLC enables a highly selective separation of various valuable products, such as sugar, furans, phenols or carboxylic acids, from the aqueous phase. This is done as part of a broad range of applications at high fow rates and pressures.