Olivine pieces up to a few cm can be dropped into the mill to weather it down to rounded shapes and small sizes without energy costs.
CO2 is captured by the weathering of olivine. This natural process has throughout geological times removed excess quantities of CO2 from the atmosphere. If all that CO2 had remained in the atmosphere there will be no life on earth. By far the most common weathering reaction is the reaction by which water and CO2 convert olivine to a magnesium bicarbonate solution and silica in solution. In the long run such solutions reach the sea where corals, shellfish and plankton convert them to solid carbonate rocks, the "ultimate sustainable storage of CO2".
Natural weathering cannot cope with the greatly increased rate of CO2 emittance and a result olivine has to be mined. To grind them to to sizes say tens to hundreds of microns require large amounts of energy.
Olivine is a silicate and the most common mineral on earth. It is the fastest weathering common mineral and it is non-toxic.
Many large olivine massifs are close to the surface where they can be mined in open pits. at low cost and a low CO2 penalty of 3.5-4% of the CO2 captured by the olivine.
To compensate for all the CO2 that had been emitted by all the coal and oil&gas that we burn amounts to 7 km3 of rock per year.
To save costs we propose the use of Natural Mills which could be either Wave Sinks out in the oceans, Whirlpools (or Maelstroms) near coasts or Wave Breaking on rocks.
It is a sustainable process keeping the environment as it is and not affecting the future and disturbing the equilibrium like how it has done in the past. Reversibility is certainly possible by cutting back the amount of olivine dispersed into the water.
Its free of charge and has no side-effects.
Category of the action
What actions do you propose?
We propose a demonstration be carried out on in the field say on a maelstrom or a wave breaking site and dump a shipload of broken and angular olivine pieces not exceeding a couple of cm and sample it downstream by dredges say after 1 day, 10 days and 100 days to see how much of it has rounded in shape and diminished in size (loss of material). The selection of the location for the demonstration to be known after studying the sites for their water flow and how far can olivine can be transported.
Alternatively a smaller trial can made to by dropping netting tubes containing olivine fragments on gravelly coastlines and picking them up later. We can examine the extent of their weathering say after a day, 10 days, 100 days or even a year.
A computer simulation can be simultaneously done to study the milling process and optimising it.
Public acceptance is important that we are not damaging the malestroms or its environment in any way. As such approvals should be obtained from local authorities prior to starting any tests.
Some background on whirlpools can be found on this media article.http://www.dailymail.co.uk/sciencetech/article-2430041/Scientists-black-holes-EARTH-Oceanic-whirlpools-thought-work-way-space-phenomena.html
Who will take these actions?
For example it would interest for example mine owners and other businesses to explore possible energy savings interested to go green.
Where will these actions be taken?
These actions could be taken in any location close to olivine sources by a miner.
What are other key benefits?
A key benefit is we can distribute the waters feeding into into the mill that have become less acidic into the open areas of the sea, ocean or lake.
Adequately small olivine sizes sub-micron to tens of microns collected could be fed into wind turbines to spread them effectively into the atmosphere arriving in distant locations. Sub-micron sizes sprayed into the atmosphere with sea-water can brighten marine clouds together with salt crystals. A white coating around them formed as a result of carbonation or externally applied paint can provide an albedo effect both at cloud level and on the ground. These particles will fall as snow or rain on the ground. Silicates are a good source of nutrients for plant growth.
Another key benefit is the growth of diatoms (a plankton group) can be promoted by the addition of silica from the weathering of olivine.
What are the proposal’s costs?
For the demonstration the cost could of mining, milling down to a few cm, transporting to the test site by ship (within reasonable distance) could cost around US$100,000. The smaller trial would cost alot less.
Up to a year.
Schuiling R.D. and Boer P.L. (2011) Rolling Stones; fast weathering in shallow seas for cost-effective CO2 capture and mitigation of global warming and ocean acidification, Earth Sys. Dyam. Discuss, 2, 551-568, doi:10.5194/esdd-2-551-2011.