[Stoves] How to make smokeless coal?

[Andrew Heggie]

Whist the suject interests me  it's drifting a bit far from the topic
of biomass cookstoves but one comment below:

On 24 May 2017 at 21:54,  <neiltm at uwclub.net> wrote:

> 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 ;-)


Neil as you say not all the products of pyrolysis from coal went into
the gas, which was refined to hydrogen, carbon monoxide and a little
inevitable nitrogen. Amonia compounds and various tars were condensed
and these tars contained many phenol compounds because the coal had
more ring like (phenolic) compounds rather then the mainly chainlike
(aliphatic) ones in wood. Coal tar was used in roads and the waste is
now considered hazardous, creosote was a good preservative because of
it's toxicity but again wood treated with it is now considered
hazardous waste. Many of the former gas works became available for
redevelopment and a whole technology was developed to detox the ground
which had become contaminated over the years.

Andrew