[Stoves] How to make smokeless coal?

[neiltm at uwclub.net]

On 22 May 2017 at 19:40, Andrew Heggie wrote:

> I do know it was a large scale technology here in UK as it
> formed part of the industrial process that linked coal mining with
> town gas with steel making.

The first use of coke in iron making was at Coalbrookdale in what is now 
the new town of Telford in Shropshire England, formerly the east 
Shropshire coalfield, and the first successful smelting of iron with coke 
from coal was by the Quaker Abraham Derby in 1777 I think it was, at 
least that is the date on his enlarged hearth, now in preservation, and 
incidentally where they still make the AGA.  It took quite a few 
experiments before he got the quality of iron he wanted that compared 
with charcoal smelted iron, and he documented the story himself.

The famous 'Iron Bridge' spanning the River Severn was an early use of 
coke smelted iron and the point at which iron making really took off, 
permitting large scale smelting not previously possible from available 
supplies of wood for charcoal.  The classic 'missionary boiling' pots 
originated there.

The process was done in open heaps, much as charcoal was made, and here 
is an excellent colour picture of it from the time, more romantic than 
detailed, but it does give that idea of open heaps, with flame breaking 
through:

http://www.wga.hu/art/l/loutherb/coalbroo.jpg

Industrial atmospheric pollution 18th century style!

But yes, coke was also used in the Bessemer converters converting pig 
iron into steel, and I can just remember seeing them shooting their 
bright flares into the night sky in the 1950s as I travelled as a small 
boy across the centre of 'The Black Country', the industrial West 
Midlands, built on a coalfield, to visit my grandparents. Both my 
grandfathers were Birmingham brassfounders.  The smogs were so bad, the 
front passenger in a car had to shine a torch out of the side window to 
find the edge of the road and steer the car while the driver hovered over 
the brake in case brake lights appeared in front. I actually did that 
once. Navigation was from memory, and sometime other cars followed you 
into your own driveway and buses got lost!  Real people died real deaths 
from respiratory difficulties in those smogs.  All for lack of a Crispin! 
Yet there was so much invention there, including stove making!

Another relation was commissioned by Birmingham City Council to make an 
engraving of the very first ever municipal gasworks at Smethwick.  Coal 
gas continued into the early 70's, which is when I remember someone 
coming to change the cooker jets in 1973 or 74 to burn the new North Sea 
gas the whole country was converting to.  I'm not aware that gas works 
were necessarily intrinsically polluting, but I may just not have come 
across references.  The process was contained after all, and tars that 
were scrubbed from the gas presumably were also utilised as the basis of 
a whole chemical industry. You can still buy 'coal tar soap', so I guess 
coal can be clean ;-) Gas coke was still available after the conversion 
for a while and into the 80s though, (perhaps from steel works by then) 
because we still burned it at home in the AGA central heating boiler, but 
some time in that decade it ceased to be available.  In the earlier part 
of the 20th century you used to be able to go down to the local gasworks 
with a bucket or two and carry home free coke!  An open coke fire pinned 
you to the opposite wall of the living room, and burned out the grates 
rather fast!

Neil Taylor (raised in the Black Country)  'Ta tar a bit'