Underground basalt deposits are presently being used to pump CO2 into, converting the basalt into a carbonate. This has already been shown to be somewhat effective.
Presently coal fired power plants use fiberglass bag filters to filter out particulates from the burning of coal. All of the combustion CO2 also passes through these filters. If basalt fibers were added to or substituted for a portion of these filters, the basalt should be able to sequester some of the CO2 by converting the basalt fibers to carbonates.
This could be done at very little extra cost to the product. Basalt fiber is a low cost commercially available product.
Experiments would need to be done to determine the density of the proposed filter material and the conversion efficiency and lifetime of the basalt material as it converts to a carbonate.
This idea is free for anyone to experiment with.