Conversion of CO2 from biogas to dimethyl ether (BIODIME)

Publieke samenvatting / Public summary

After the Paris climate agreement, industry is under increasing pressure to reduce the emissions of CO2 significantly ‚Äúdecarbonization of industry‚ÄĚ. At the same time, the energy sector is changing drastically, replacing fossil by renewable energy sources. One of the key aspects is to decarbonize the energy mix. One part of that is capturing and removing CO2 from all kind of different sources. In order to make this more economically attractive an effort is needed towards valorization of the CO2 into products (utilization). In case of biogas production 40% CO2 is present in the gas stream and is currently not directly utilized. Converting this in a valuable product will further strengthen the decarbonization. Biogas consist of 60% methane and 40% CO2. The biogas can be given a higher added value by the production of dimethyl ether (DME). Both methane as well as CO2 are needed for this conversion. First green hydrogen is produced from the methane. The hydrogen reacts with CO2 to methanol, followed by the conversion of methanol to DME. Thus, a higher density energy carrier and transportation fuel is produced, while significant reductions in CO2 emissions can be realized simultaneously.

The BioDiME project will design and develop a new process concept to produce DME from CO2 rich gasses such as biogas. The basic idea of this novel concept comprises an in-situ separation of water from the reaction-product gas mixture (CO, CO2, H2, DME, methanol). This will lead to a much simpler and cost effective process. This concept enables the widespread application of production of DME/methanol from biogas. At the same time a significant reduction of CO2 emissions can be achieved. Per ton DME produced 1.91 ton CO2 is consumed, and therefore CO2 emissions will be avoided. For a reference case of 1000 m3/h biogas production, 6400 ton of CO2 emissions can be avoided per year. The technology is not specific for biogas, but could as well be used in the integration of energy storage and conversion with other CO2 sources.

Korte omschrijving
The project is divided in five work packages:
WP1 User requirements: Definition of composition and flow rates of feed and product streams
WP2 Membrane preparation: Preparation and testing of water selective membranes
WP3 Process development: Design, construction and testing of reactor-separation equipment
WP4 Technical & economic evaluation: Modelling of scale up and economic evaluation
WP5 Dissemination: Outlining an implementation/commercialization plan
In short the project activities are:
A water selective membrane with high water permeability and high gas retention will be developed and tested in the novel reactor-separation equipment. Proof of concept tests will be performed to test the in-situ separation of water from the reaction-product mixture in a membrane reactor-separator. The implementation of this concept results in enhanced reaction rates, an integrated reaction-separation process, improved catalyst lifetime and conversion beyond equilibrium constraints due to selective removal of water. The results of the experimental tests will be used to design a scale up model which forms the basis for economic evaluation, cashflow analysis and dissemination plan of this c

The result of the project is an innovative technology, or process concept, to produce DME from CO2 and CH4 from biogas. This technology, an in-situ separation of water from the reaction-product gas mixture, will be tested at lab scale. Design rules to scale up the technology will be defined that form a basis to implement the system at commercial scale. The following will be delivered:
1. A water selective membrane.
2. A proof of concept for a membrane reactor-separation equipment.
3. A scale up design, cashflow analysis and economic evaluation of the novel concept for the production of DME using biogas, a CO2 rich feed.