camelot-forum.co.uk

This is interesting... (https://www.bbc.co.uk/news/science-environment-65648361)

But the tiny pieces of basalt rock that are left over are prized by Jim's company. They have a useful property - when they weather in the rain they remove carbon dioxide from the atmosphere...
It requires no specialist equipment. A trailer is loaded with 20 tonnes of basalt [powder/dust] before a tractor drags it up and down, a rotating wheel at the back scattering the tiny rocks.

"It's free of charge which is quite important to a farmer," John Logan tells me with a chuckle as the basalt is put on his field. He'd seen UNDO's trials on a neighbouring farm.

"It looks like it's going to make the grass better, so that can only be good for the cattle because they're eating better grass."

For quite a few years now I have been aware of organic - or maybe biodynamic - gardeners using ground rock for mineral replenishment(?) in vegetable gardens. I was suspicious because a) I thought that a compost-garden would be pretty well self-sustaining anyway, and b) I didn't really believe that you could justify the energy needed to blast out rock then crush it to powder.
However if using the waste dust from (basic-rock) mineral extraction both enhances CO₂ uptake and fertilises the soil, what's not to like?
A

Absolute snake oil. Quarry waste that nobody wants suddenly has a value to gullable people. You might get a slight benefit from improved drainage but even that is stretching it with the minute quantities applied. No the real quarries use this waste to produce added value products like blocks and beams.

renewablejohn wrote: ↑Tue May 30, 2023 9:08 pm Absolute snake oil. Quarry waste that nobody wants suddenly has a value to gullable people. You might get a slight benefit from improved drainage but even that is stretching it with the minute quantities applied. No the real quarries use this waste to produce added value products like blocks and beams.

I'm not dismissing it as there seems to be some momentum... e.g. https://www.sheffield.ac.uk/research/rock-dust
A

renewablejohn wrote: ↑Tue May 30, 2023 9:08 pmAbsolute snake oil. Quarry waste that nobody wants suddenly has a value to gullable people. You might get a slight benefit from improved drainage but even that is stretching it with the minute quantities applied. No the real quarries use this waste to produce added value products like blocks and beams.

Only works for certain rock types, i.e. igneous ones which will react chemically with atmospheric carbon dioxide to form carbonates. As such, it's probably the most fundamental part of the earth's carbon cycle (at least on long timeframes) - https://en.wikipedia.org/wiki/Carbonate–silicate_cycle
The logistics of shifting the megatonnes of the stuff around the world to the right places (presumably added to fertilizer mixes?) aren't even that hard, but right now the financial justification doesn't exist. Either we need to pay farmers for CO₂ removal (hard to justify without carbon taxes) or we need to demonstrate that the performance of the fertilizer is somehow improved.

Ah interesting. I also couldn't see past the cost and emissions of producing the rock dust, but the study points out that we've been mining a long time so "stockpiles" should exist.

AE-NMidlands wrote: ↑Tue May 30, 2023 10:26 pm

renewablejohn wrote: ↑Tue May 30, 2023 9:08 pm Absolute snake oil. Quarry waste that nobody wants suddenly has a value to gullable people. You might get a slight benefit from improved drainage but even that is stretching it with the minute quantities applied. No the real quarries use this waste to produce added value products like blocks and beams.

I'm not dismissing it as there seems to be some momentum... e.g. https://www.sheffield.ac.uk/research/rock-dust
A

Still snake oil. How do you think this rock is around for so many millions of years because it weathers extremly slooooooooooooooooooowly.

No just another example of a greenwash society jumping on a bandwagon to make money from a problem that does not exist.

Paul_F wrote: ↑Wed May 31, 2023 6:58 am

renewablejohn wrote: ↑Tue May 30, 2023 9:08 pmAbsolute snake oil. Quarry waste that nobody wants suddenly has a value to gullable people. You might get a slight benefit from improved drainage but even that is stretching it with the minute quantities applied. No the real quarries use this waste to produce added value products like blocks and beams.

Only works for certain rock types, i.e. igneous ones which will react chemically with atmospheric carbon dioxide to form carbonates. As such, it's probably the most fundamental part of the earth's carbon cycle (at least on long timeframes) - https://en.wikipedia.org/wiki/Carbonate–silicate_cycle
The logistics of shifting the megatonnes of the stuff around the world to the right places (presumably added to fertilizer mixes?) aren't even that hard, but right now the financial justification doesn't exist. Either we need to pay farmers for CO₂ removal (hard to justify without carbon taxes) or we need to demonstrate that the performance of the fertilizer is somehow improved.

Or we need to admit that actually we got it wrong in that CO2 is not a climate problem at all at its present levels but could become a very serious problem if allowed to go much lower. Even at current levels plants are struggling to survive which is why farmers with glasshouses increase the level of CO2 as the plants respond with higher yields.

renewablejohn wrote: ↑Wed May 31, 2023 7:19 am

AE-NMidlands wrote: ↑Tue May 30, 2023 10:26 pm

renewablejohn wrote: ↑Tue May 30, 2023 9:08 pm Absolute snake oil. Quarry waste that nobody wants suddenly has a value to gullable people. You might get a slight benefit from improved drainage but even that is stretching it with the minute quantities applied. No the real quarries use this waste to produce added value products like blocks and beams.

I'm not dismissing it as there seems to be some momentum... e.g. https://www.sheffield.ac.uk/research/rock-dust
A

Still snake oil. How do you think this rock is around for so many millions of years because it weathers extremly slooooooooooooooooooowly.
No just another example of a greenwash society jumping on a bandwagon to make money from a problem that does not exist.

the rock "around for so many millions of years " is dense and solid, usually wet, underground and not in contact with the air. Finely divided (ground to powder) and dispersed it is a totally different situation. (One of the first things that geologists are taught is that to see a rock proprely you have to break it... because a weathered surface is so different to the way it looks when fresh.) You could illustrate it by considering a tree: as it stands it isn't a fire risk, split it into fingers and it burns easily, reduce it to dust and it will explode.
It seems perfectly reasonable to me that powdered basic (alkaline) rock will react with CO₂ Whether it is justifiable to use energy to create the dust when we haven't done anything about reducing energy consumption in the first place is another matter.
The cynic in me just thinks it is a cheap way of getting rid of waste that the quarry would otherwise pay to dump.

I remember as a kid in iceland looking at the rolling land seas of solidified laval flow that drainage assistance here in the fens would be good.

When faced with the sheer amount of land hogging rock (island pop 225,000 back then) I did wonder how long till the small coastal access populations needed to shift it rather than build round it, ..also taking into account their scandic superstitious nature re spirit people, big rocks became parks.

For modern estate builders it was build where there was a flat gap (or maybe pound an area flat, then build a domecile) ...the road area from haff - reyk went through enough basalt laval land to make estate builders cry, ..if there is a secondary market now for crushed rock for earth stabilisation, drainage etc then where is it likely to travel from? spain , canaries? iceland by boat?

Bog wood rising through ploughed fields here makes you think about that sort of thing, it is a wind blown area here so surface losses of peatland etc.

AE-NMidlands wrote: ↑Wed May 31, 2023 8:27 am

renewablejohn wrote: ↑Wed May 31, 2023 7:19 am

AE-NMidlands wrote: ↑Tue May 30, 2023 10:26 pm
I'm not dismissing it as there seems to be some momentum... e.g. https://www.sheffield.ac.uk/research/rock-dust
A

Still snake oil. How do you think this rock is around for so many millions of years because it weathers extremly slooooooooooooooooooowly.
No just another example of a greenwash society jumping on a bandwagon to make money from a problem that does not exist.

the rock "around for so many millions of years " is dense and solid, usually wet, underground and not in contact with the air. Finely divided (ground to powder) and dispersed it is a totally different situation. (One of the first things that geologists are taught is that to see a rock proprely you have to break it... because a weathered surface is so different to the way it looks when fresh.) You could illustrate it by considering a tree: as it stands it isn't a fire risk, split it into fingers and it burns easily, reduce it to dust and it will explode.
It seems perfectly reasonable to me that powdered basic (alkaline) rock will react with CO₂ Whether it is justifiable to use energy to create the dust when we haven't done anything about reducing energy consumption in the first place is another matter.
The cynic in me just thinks it is a cheap way of getting rid of waste that the quarry would otherwise pay to dump.

But very little of it is fresh what there doing is dumping quarry waste probably crushed 50 years ago on agricultural land for some mythical benefit and charging a fortune to a load of idiots who believe in this greenwash nonsense.