Dutch Professor Olaf Schuiling has been working on rock grinding for many years.Â Remember the Virgin Earth Challenge, launched early 2007 with the promise to award $35 million to the best method to remove greenhouse gases? Schuiling said: Let's grind more rocks! Last thing Schuiling heard was that he was among the final ten contenders.
Schuiling's method is simple. Crush olivine rock to small pieces and it will bind with carbon dioxide. This process - called weathering - happensÂ in nature but takes a long time. Crushing and grinding olivine rock will speed up the process and is therefore often called enhanced weathering.Â It works best in wet tropical countries, but can be done everywhere around the world.
Schuiling proposes to cover beaches, levees andÂ railway tracksÂ with the material, andÂ proposes olivine to be added to building materials like pavement and concrete. It can also be added to soil and water. Adding olivine canÂ fertilize the soil and improve its ability to retain water, and can work well in combination with biochar and other ways to increase organic carbon in the soil. When added to the sea, it canÂ reduce acidification, andÂ stimulate growth of diatoms and other forms of biomass in the sea.
This is a win-win solution, Schuiling says, as it helps grow more food, while combating global warming. To add another win, it can alsoÂ produce drinking water that is healthier than rain water.Â Schuiling recommends cities to build olivine hills, toÂ remove carbon dioxide from the air while filtering water.