TASK 2: Gas reforming
In the indirect gasification the temperature of the gasifier is only around
750 °C which leads to high concentrations of tar components and light
hydrocarbons in the producer gas instead of targeted syngas components (CH4,
CO, CO2 and H2). Tar consists of heavy hydrocarbons, like naphthalene, which
can also accumulate to pipelines, and can cause clogging and coking in the
downstream process units, and therefore it is necessary to process the tar
components to lighter molecules.
A catalytic reforming process is typically used for the cleaning of tar and
hydrocarbons from the gasification gas. In this task the main research
objective is an externally heated steam reformer and especially the following
• comparison of several catalysts in order to find the best suited catalyst
for the production of clean syngas for the methane synthesis
the best operation conditions
• investigating the effect of and
reasons for the coking phenomenon.
The typical catalysts in the steam reforming processes are nickel, precious
metals and zirconia. There are many commercial versions of these catalysts,
and it is also possible to develop a suitable catalyst in the VTT
laboratories. VTT has developed gas reforming technology for gasification
since the late 80’s, and especially during the UCG and UCGFunda projects new
catalysts and reformer concepts have been tested and developed for syngas
production. In this project the technology can be upgraded and modified to
meet the requirements of the externally heated reformer.
The catalyst testing will be carried out in laboratory and bench scale fixed
bed reactors in both atmospheric and pressurized conditions. After
optimization of the proper catalyst combination in laboratory, bench scale
experiments will be performed to determine the long term stability and the
coking resistance of the chosen catalysts.