|
Ref. NO. : ISO/R 158- 1960 (E)
v
-----ICI-- -t-
0
IS0
1 NT ERN AT1 ON AL O RG A N IZATl ON FOR STA N DA RD IZATl O N
IS0 RECOMMENDATION
O
R 158
DETERMINATION OF ASH OF HARD COAL
1st EDITION
June 1960
COPYRIGHT RESERVED
The copyright of IS0 Recommendations and IS0 Standards
belongs to IS0 Member Bodies. Reproduction of these
documents, in any country, may be authorized therefore only
by the natioaal standards organization of that country, being
a member of ISO.
_.
For each individual country the only valid standard is the national standard of that country.
Printed in Switzerland
Copies to be obtained through the national standards organizations.
Also issued in French and Russian.
_- _.
---------------------- Page: 1 ----------------------
BRIEF HISTORY
The IS0 Recommendation R 158, Determination of Ash of Hard Coal, was drawn up by
Technical Committee ISO/TC 27, Solid Mineral Fuels, the Secretariat of which is held by the
British Standards Institution (B.S.I.).
At the first meeting of ISO/TC 27, held in London, in March 1950, national standards
for the determination of ash were compared.
At the second meeting, held in London, in November 1951, this subject was further dis-
cussed and provisional decisions were reached on certain details.
At the third meeting, held in London, in November 1953, it was agreed that a draft pro-
posal should be prepared and that Working Group No. 2, Ash and Moisture, should attempt
to resolve certain outstanding difficulties experimentally.
The first draft proposal was circulated in June 1954. It was considered by the Working
Group, together with a counter-proposal from Belgium, at a meeting in October 1954. Six
methods for determining ash were demonstrated. After considering all the results, it was agreed
that the one-furnace method should be adopted and that the temperature should be raised from
cold to 500 "C in 30 minutes and from 500 "C to the final temperature in 30 to 60 minutes.
For the final temperature, a compromise figure of 815 f 10 "C was adopted.
A second draft proposal incorporating these decisions was circulated in January 1955
to the members of the Committee and was studied, together with the report of the Working
Group, at the fourth meeting of ISO/TC 27, held in Stockholm in June 1955. It was agreed
that the method should only apply to hard coal, since the question of the final temperature
for brown coals and lignites required further investigation. A decision reached at that time
was later revoked, and the choice of using a 1 g or a 2 g sample was restored. It was agreed
that a new draft proposal should be drawn up on that basis.
This draft proposal for an IS0 Recommendation was circulated in June 1956 to the
Members of ISO/TC 27, and, with minor changes, was adopted as a Draft IS0 Recommendation.
On 29 June 1957, the Draft IS0 Recommendation (No. 170) was distributed to all the
IS0 Member Bodies and was approved, subject to some modifications, by the following 23
(out of a total of 38) Member Bodies:
Austria *Ireland Sweden
*Canada Italy *Switzerland
Czechoslovakia Mexico *Union of
South Africa
Denmark Netherlands
*New Zealand United Kingdom
*Germany
*Greece *Portugal U.S.A.
*U.S.S.R.
Hungary Romania
Spain *Yugoslavia
India
One Member Body opposed the approval of the Draft: Belgium.
The Draft IS0 Recommendation was then submitted by correspondence to the IS0
Council, which decided, in June 1960, to accept it as an IS0 RECOMMENDATION.
---------------------- Page: 2 ----------------------
ISO/R 158 - 1960 (E)
-
IS0 Recommendation
R 158 June 1960
DETERMINATION OF ASH OF HARD COAL
1. INTRODUCTION
When coal is incinerated completely, the ash remaining differs from, and is less than, the mineral
matter originally present in the coal. This is because various changes occur during incineration,
such as loss of water of constitution from shaly matter and of carbon dioxide from carbonates
and the oxidation of iron pyrites to iron oxide. The fixation of oxides of sulphur by bases also
occurs. The method for the determination of ash in coal is, therefore, empirical, because the
conditions of incineration determine the extent to which these reactions occur. It is essential
...