I have no idea about the economics, though, maybe it's just not feasible without subsidies.
Edit: Why? Because the technique is simple, biomass is relatively cheap, you get electricity and heat you can sell in a cold climate, and that terra preta example makes me envious, as someone interested in gardening. If the char was cheap enough, I would want to buy lots of it myself. Helping the planet and helping my own plants.
I think you need a large scale plant to keep costs down. There are large scale biomass power plants where I live, but they specialize in burning everything, so some investment is needed.
I have a client in the biochar industry. They manufacturer "machines" or furnaces to produce biochar, as well as sell it directly. https://newenglandbiochar.com
Using biochar in your garden, on your lawn etc. is a great way to sequester some carbon at a small scale.
I agree with the biochar suggestion, but I'd also suggest to bury both biochar and syn-oil deep in the ground -- at least, in the first decades or so. That's because I don't believe the usual sales pitch for biochar actually works.
Biochar as a soil amendment is not a reliable means to increase yields. Depending on the produce and the soil, it decreases yields. Sometimes, it seem to have no effect, at all. So far, the most reliable results have been observed in tropical areas. People there don't have the money to invest in farm land, yet.
Refining syn-oil is hard, because its quality is low -- comparable to bunker oil. Tar is one of the few products that can be made out of it, successfully.
Therefore, burying both seem to be the best option. After all, there should be quite a few depleted oil fields and coal mines in the world, so space is not a problem.
https://en.wikipedia.org/wiki/Biochar
Sell the biochar to homeowners:
http://www.ultrakulture.com/wp-content/uploads/2015/10/4-Ter...
I have no idea about the economics, though, maybe it's just not feasible without subsidies.
Edit: Why? Because the technique is simple, biomass is relatively cheap, you get electricity and heat you can sell in a cold climate, and that terra preta example makes me envious, as someone interested in gardening. If the char was cheap enough, I would want to buy lots of it myself. Helping the planet and helping my own plants.
I think you need a large scale plant to keep costs down. There are large scale biomass power plants where I live, but they specialize in burning everything, so some investment is needed.