BRIQUETTING TESTS. 
45 
action of wa'.er unless rendered waterproof through the application of other substances. 
On the other hand some briquettes which remain firm under the action of water crumble 
when heated because of the fact that the binding material used volatilizes at a low tempera- 
ture. Even in the coking coals the binder should hold the particles together at least until 
the coal itself is sufficiently softened to cohere and begin burning. 
(5) It should not add appreciably to the ash of the coal nor increase the clinker forma- 
tion in the ash. It should not give off fumes nor seriously increase the smoke in the burning 
of the briquettes. It is generally claimed that owing to the more perfect combustion in 
burning briquettes, less smoke is produced from the coal and binder together than is given 
off from the consumption of the unbriquetted or natural coal. Binding materials which 
have a low melting or boiling temperature give off more smoke because of the fact that 
this smoke originates at a temperature too low for complete combustion. Briquettes, as 
in the case of lump coal, give off less smoke when the arrangements for proper draft are 
such as to facilitate combustion. 
(6) The binding material should increase, or certainly should not decrease, the heating 
quali'.y of the coal which is used in the manufacture of the briquettes. 
BRIQUETTING WITHOUT THE USE OF BINDING MATERIALS. 
In August, 1904, under the writer's supervision, samples of lignite from Lehigh, N. Dak., 
and from near Rockdale, Tex., were shipped to Magdeburg and Zeicz, Germany, to be used 
for experiments to determine the feasibility of briquetting these lignites with the German 
presses. These tests were conducted by the writer. They were entirely successful and 
the briquettes made with these lignites, after being crushed and dried, subsequently stood 
the tests applied to the German lignite briquettes, which are extensively used for domestic 
purposes. 
To a portion of the briquettes made at Magdeburg 2 per cent of ordinary coal-tar pitch 
was added, with the view of determining what, if any, advantage would result from such 
an addition. Laboratory «;ests indicated that the briquettes to which this pitch had been 
added burned more rapidly, with more flame, and at a higher heat efficiency than those 
without it, and the North Dakota lignite seemed to give off fewer sparks in burning. It 
is estimated that the cost of manufacturing these briquettes (not including the cost of the 
lignLe) should not exceed 50 cents per ton. The analyses of the lignite briquettes made 
at Magdeburg are as follows: 
Analyses of lignite briquettes made at Magdeburg, Germany. 
[Dried before briquetting.] 
From Lehigh, N. Dak. 
From Rockdale, Tex. 
Without 
pitch or 
other 
binder. 
With 
2 per cent 
of pitch 
added. 
Without 
pitch or 
other 
binder. 
With 
2 per cent 
of pitch 
added. 
aj 
f Moisture 
12.96 
37.79 
38.63 
10.62 
.75 
4.99 
52.88 
.65 
30.11 
4.941 
8,894 
28 
11.22 
38.68 
41.11 
8.99 
1.04 
5.09 
56.26 
.73 
27.89 
5,332 
9,598 
.87 
8.88 
40. 92 
41.90 
8.30 
.97 
5.21 
59.06 
1.15 
25.31 
5 682 
10,228 
32 
8.92 
08 
Volatile matter 
41.33 
Fixed carbon 
42. 35 
Pi 
JAsh 
7.40 
f [Sulphur 
1.07 
09 
Hydrogen 
5.23 
CO 
Carbon 
59.61 
£> 
N itrogen 
1.14 
u> 
Oxygen 
25.55 
OaW 
>ries 
5.828 
Bri 
Moi 
M 
,ish thermal units 
10, 490 
sture in undried sample of lignite as received at 
agdeburg 
07 
