Blue Lagoon on the Reykjanes Peninsula in Iceland is one of the most popular place for tourism in the country. Most tourists who visit Iceland make a stop there and plunge their bodies in the blue water spewed by the Svartsengi geothermal plant that has been operational since 1976. Now a small Icelandic company is hoping to turn a profit from the waste carbon dioxide from the same plant.
Carbon Recycling International has built an adjacent plant that converts the carbon dioxide into methanol, a fuel for making plywood, paints, solvents and other products. It may be the first company in the world to demonstrate a commercially viable way of making liquid fuel directly from carbon dioxide, something that could help reduce greenhouse gas emissions.
The carbon dioxide emitted by the geothermal plant is cheaper to capture than the carbon dioxide from fossil-fuel power plants. At coal-fired plants, carbon dioxide is a product of burning coal in air ; the resulting flue gas, like air, is mostly nitrogen, and separating the carbon dioxide is expensive.
Carbon Recycling International brands its methanol Vulcanol because “it’s made with energy from a volcano.” The amount of carbon dioxide produced by the geothermal plant is relatively small, roughly one-20th as much as for coal-fired power plants per kilowatt-hour of electricity. But the geothermal plant emits highly concentrated streams of carbon dioxide that require less energy and equipment to separate and capture.
To make methanol from carbon dioxide, you need a source of hydrogen, since methanol (CH3OH) is partly made of hydrogen. Hydrogen is also a fuel in its own right and provides the chemical energy needed to form methanol. Carbon Recycling International gets its hydrogen by using electricity from the geothermal power plant to split water. The process will be profitable by next year, when its five-million-litre methanol plant is operating at full capacity.
Researchers are looking at other ideas for making carbon recycling profitable. Catalysts are being developed that decrease the amount of energy required to turn carbon dioxide into useful chemicals, and also make it possible to produce chemicals more valuable than methanol, such as propanol. With the price of electricity in Iceland, you could make a ton of propanol (which sells for about $3,200) with less than $800 of electricity. The market for propanol, however, is relatively small.
Source : C. Grandpey & MIT Review.