By Michael Markrich copyright 2022

What if you could get rid of the air pollution from the smoke stack of a power plant?  Not just reduce its impact with a chemical scrubber as is done now. But take it completely out of the atmosphere and sequester it forever below the ground in stone? This may sound like science fiction but this is currently what is happening in Iceland. Soon it may be taking place all over the world. The process can be viewed here. https://www.carbfix.com/how-it-works

Some consider this carbon sequestration process called CARB FIX the only way to put a cap on the green house gases that are steadily increasing in the upper atmosphere. The problem has been more carbon dioxide is being released into the earth’s atmosphere than is being removed. While world leaders generally acknowledge this, there is no political consensus among nations to reduce carbon emissions. in a timely manner.

Some scientists believe that if the world’s nations continue to emit greenhouse gases into the upper atmosphere at the present rate, so great will be the effects of global warming that more than 20% of the earths surface will be uninhabitable within 50 years. It will just be too hot and there won’t be enough water.

During the early 2000s some scientists in Iceland began looking at a technological rather than a political solution using geochemistry. They reasoned there were two ways to take carbon out of the atmosphere - from the carbon infused smoke plumes from generating plants or through a process known as Direct Air Capture (DAC) whereby the carbon is essentially filtered out of the air and turned into a gas. The question then became if one could remove carbon from the air and turn it into a gas, where would you store it.

In 2006 a group of engineers in Iceland began to look at the natural process by which carbon dioxide dissolves in water and turns to limestone as a solution. In nature, when there is forest fire caused by lightning for example, vast plumes of carbon smoke enter the atmosphere. When it rains the carbon dissolves into the water, and the carbonized water sinks into the earth. In some areas where there are particular kinds of stones such as basalt which is common in Hawaii and Iceland, a chemical reaction ensues and the carbon is stabilized in the rock formation as limestone.

What the scientists wanted to know was whether this naturally occurring process could be done in a controlled way. They wondered specifically if carbon could be turned into limestone if it was taken from the plume of a generating plant, mixed with water and then injected deep into a basalt rock formation.

In 2007 what had started as a scientific paper became an organized experiment to work on the first experiment of this kind in the world.

The scientists included Holmfridur Sigurdottir, Dr. Sigurdur Gislason and Dr. Eric Oelkers. Grants were written and funds were obtained from Reykjavik Energy,  the University of Iceland, The Centre National de la Recherche in Toulouse, France and The Earth Institute of Columbia University in New York.

After six years of experiment and having obtained proper permits, they began the first trial injections of carbon infused water into rock at a pilot project site in Iceland. In 2012, between January to March, 175 tons of pure CO2  was dissolved and injected to about 1500 feet of depth at a temperature of 95 Farhenheit and from June to August 73 tons of 75% CO2 – 25% H2S gas mixture (the plume from the power plant there) were injected under the same conditions.

To the great pleasure of the scientists it was found that the injected water carbon dioxide mixture did not leak out of the porous basalt rock into the atmosphere but instead when combined with naturally occurring magnesium, calcium and iron - turned into limestone within two years. The success of these experiments led to more funding from the European Union and approval to work directly on the waste stream at the 303 MW Hellisheidi power plant.

The work at the 303 MW Hellisheidi power plant involved capturing approximately 10,000 tons of waste carbon dioxide (about 1/3 of the total) by filtering it out of the hot plume of steam and carbon, then after mixing it with water- injecting it  into basaltic rock, 550 feet below the surface. Over a two year period the carbon dioxide and acid mixture  combined naturally with calcium and magnesium into limestone.       

The work they did at the generating plant; the second largest geothermal power plant in the world which powers seven generators, was very challenging. The water and hydrogen sulfide proved difficult to handle. Once in the ground the carbon dioxide mix had to be monitored as it turned into limestone,

The project has been so successful that the engineers who created the program developed a company to reproduce this technology in power plants throughout the world. Their company name is called CARB Fix.

The current carbon dioxide of the plant is 34,000 tons and this year, 2022, after 15 years of experimentation the plan is to remove all the carbon dioxide from the plume and inject it in the ground. The  intention is to create a plant that is completely self sufficient, and will remove 10% of carbon emissions from Iceland.

It is hoped that this process will become a model for power plants all over the world as well for steel and other kinds of plants that use large amounts of heat and release large amounts of carbon dioxide. The developers of this process believe that Iceland is an ideal place for a model plant of this kind because, like Hawaii, it is 90%  basalt which is ideal for carbon storage.

Direct Air Capture (DAC) 

 (DAC) is based on the premise that it is likely that the world is not going to be able to reduce the amount of carbon dioxide in the atmosphere significantly by any other means but technology. The other solutions such as planting trees as a way of sequestering carbon or restoring the health of soils take a long time.

For this reason many policy makers and scientists believe it is better just to develop the technological means to remove carbon dioxide from the air. Direct Air Capture is now considered a completely novel and new technology. But it may one day become the norm.

In 2017 Carb Fix began working with a Swiss Company called Climeworks which develops technology to filter carbon dioxide directly out of the air. Their facility is currently able to remove 50 tons Carbon Dioxide per year about the same equivalent as 2000 trees. However in order to combat global warming many millions of tons of Carbon Dioxide will need to be removed from the atmosphere.

Carb Fix is working with Clime Works to turn that recovered Carbon Dioxide into stone. It is a hugely ambitious experiment - on which some think the future of the world may depend.