~ COAL ECONOMY. 
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against the cost of producing and handling coal dust and the difficulties 
which may have to be overcome in dealing with its ash. 
The following are the main conclusions reached in his report by Mr. L. 
_ GC. Harvey, the investigator appointed by the British Iuel Board :-— 
1. The advantages of burning coal in pulverized form have been definitely proved 
in actual practice. 
2. The heat values of coals can be utilized to a far higher degree by this means 
of firing than by any other process. ; 
3. In certain circumstances initial costs for pulverized coal plants are considerably 
less than the costs for installing producer gas plants. ‘ 
4. Economy in fuel consumption of from 20 to 50 per cent. can in many cases be 
effected by the use of coal in pulverized form. 
Of the 513,500,000 tons of coal used in America in 1914 for all purposes, - 
of which, say, 205,400,000 tons were used in the metallurgical and steel 
industries and for railway locomotives, some 41,000,000 tons would have 
been saved if pulverized coal had been used exclusively for these purposes. 
. Almost any grade or quality of fuel—anthracite, bituminous, lignite, or peat— 
can be used efficiently in certain circumstances in pulverized form. 
6. Large quantities of what is considered waste coal can be used to good purpose. 
7. In suitably designed plants there is practically no danger whatever of the 
possible explosion of coal dust. ‘ opie 
8. A very important start has been made in connexion with the firing of large. 
power-house boiler plants with pulverized coal, and its extension in this 
direction is likely to develop rapidly. . 
9. In view of the attention now being given to marine boiler firing by this means, 
useful and important results are to be expected. ; 
10. Owing to the very considerably reduced. amount of labour incidental to a 
pulverized coal plant, as compared with hand firing and, in certain cases, 
stoker firing, the labour saving is a most important feature introduced 
by this system of burning coal. : 
Saving in labour is particularly marked in connexion with the firing 
of railway locomotives by this means. ; : 
11. In view of the smokeless combustion of pulverized coal in metallurgical fur- 
naces, and especially in the stecl industries, for boiler firing and for loco- 
motives, the abatement of smoke nuisances in large cities by this means 
can be accomplished to an appreciable extent. 
or 
: 5. DOMESTIC HEATING. 
The British Fuel Research Board has carried out, on behalf of the Man- 
chester Air Pollution Board, valuable investigations into the efficiency of 
open fires used for domestic heating. The results are to be published by 
the Board asa special report. From the outline of them, given in the Board’s  - 
General Report, it appears that they are likely to prove of very great interest 
to the general public. In addition to the direct determination of the heat 
emitted by an open fire, measurements were made of the volume and tempera- 
ture of the gases passing up the chimney, so that the heat loss due to this. 
cause was ascertained. This loss was found to vary with the amount” of 
‘outside air drawn into the room. With an amount sufficient to change the 
air in the room once every hour, the loss was only 16 per cent., while with 
ten times this amount of air the loss rose to 50 per cent. 
Another important result established by the Board is the superior radiat- 
ing quality of coke fires, in particular when the coke used has heen made by 
carbonization at a temperature much’lower than that used in coke ovens or 
gas retorts. If in addition to its quality of smokelessness, this form of fuel 
can be credited with a much higher thermal efficiency than coal when it is 
burned in open fires under suitable conditions, it is evident that the replace- 
ment of raw coal by this material would give a new lease of life to the much 
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