(Source: VTT Technical Research Centre of Finland)(Source: VTT Technical Research Centre of Finland)VTT Technical Research Centre of Finland and Lappeenranta University of Technology (LUT) are now testing the Soletair demo plant designed to use carbon dioxide to produce renewable fuels and chemicals. The pilot plant is coupled to LUT’s solar power plant in Lappeenranta.

The project will demonstrate the technical performance of the overall process and produce 200 liters of fuels and other hydrocarbons for research purposes. The demo plant incorporates the entire process chain, and comprises four separate units: a solar power plant; equipment for separating carbon dioxide and water from the air; a section that uses electrolysis to produce hydrogen; and synthesis equipment for producing a crude-oil substitute from carbon dioxide and hydrogen.

A 206.5 kW capacity photovoltaic system generates electricity for the hydrogen production unit—the most energy intensive part in the system. The renewable energy plant consists of flat roof, carport, wall, 2-axis tracking, and manual tracking solar PV installations. The total installed power is 206.5 kW.

A proton exchange membrane (PEM) water electrolysis system produces high-purity hydrogen gas at elevated pressures. Hydrogen is used with recycled carbon dioxide to produce renewable fuels, raw materials, and chemicals. The hydrogen production system is built in a standard shipping container and virtually connected to the PV power plant at LUT.

Produced dry hydrogen gas is stored into two 350 l composite cylinders. From the gas storage, the hydrogen can be supplied to the mobile synthesis unit (MOBSU) or a PEM fuel cell located in the hydrogen production container.

The direct air capture unit is a modified version of air-scrubbing units for civil shelters. The sorbents used to collect carbon dioxide are amine-functionalized polystyrene spherical beads.

The MOBSU uses Fischer-Tropsch synthesis to combine carbon and hydrogen and produce valuable gas, liquid, and solid products for various uses.