@
DebF_EONNext
There is that. For me, de-ashing the wood burner, cleaning the glass and then laying it up ready for the evening is just part of the daily routine and the wood ash is a useful addition to the compost bins. The carbon balances the excess nitrogen from the chicken litter. Wood Ash is very handy around the garden too. But never use coal ash as it contains heavy metals and other toxic nasties.
Coal ash does have two uses which is why I used to keep it at my old place. Coal ash is gritty so in very small quantities it is useful on concrete paths or drives in icy conditions.
Coal ash, if finely sieved to remove lumps can be used to replace up to 30% of Portland Cement when making mortar or concrete. So called 'pozzolanic cement' takes a bit longer to set than regular concrete but is much more durable and significantly more water resistant. Cement manufacture is a very energy intensive process and generates huge amounts of CO2, but the carbon footprint of pozzolanic concrete is half that of regular. You've already had the benefit of the energy by burning the coal, so being able to use the 'arisings' as a lower carbon building material does make it slightly more environmentally friendly. You are also locking up those toxins in the concrete and even in adverse conditions, those toxins don't leach out again. So pozzolanic cement is an environmental win, compared to just dumping the ash. 👍
When I first moved to Wales, we replaced a compacted mud floor in a barn with a four inch layer of concrete. We saved an entire winter's worth of coal ash from the furnace and saved ourselves seventeen bags of Portland Cement by using the ash in the mix. Hardstanding for a tractor, dumper truck, minidigger and all the smaller machinery. No more muddy barn, £100 saving on the cost of the floor and getting the most environmental result possible from coal-burning. Winner winner chicken dinner 😇