16 
BULLETIN 98 ; U. S. DEPARTMENT OF AGRICULTURE. 
Table IX. — Specific heat of brine with different percentages of salt. 
Per cent 
of salt. 
Specific 
heat of 
brine. 
Per cent 
of salt. 
Specific 
heat of 
brine. 

1 
5 
10 
1.000 
.992 
.960 
.892 
15 
20 
25 
0.855 
.829 
.783 
2 
tfejse 
Sl«r 
5 8 m 
X 
Fig. 
a /O /2 /■* /6 /a 20 22 B4 26 
percentage: of salt wrtxTuFiE. 
.—Refrigeration available with different percentages of 
salt. 
Usually salt when added to ice is of a higher temperature than 
that of the ice; consequently the correction for its heat above 32° F. 
must be subtracted from 
the available refrigeration 
shown by the curve, figure 
4; and if the brine is al- 
lowed to escape at a tem- 
perature below 32° F. the 
refrigeration lost in the dis- 
charge brine must be sub- 
tracted, while, on the other 
hand, if the discharge brine 
is at a temperature higher 
than 32° F. the correction 
must be added. 
If given amounts of ice 
and salt, at a temperature 
of 32° F. are mixed together and the mixture supplied with suffi- 
cient heat to melt the ice and dissolve the salt and raise the tem- 
perature of the resulting brine to 
the original temperature of 32° 
F., then the total amount of heat 
absorbed by the reaction will be 
the sum of the latent heat of the 
ice and the heat of solution of the 
salt to form the resulting brine of 
the density which will result from 
the particular proportion of salt 
and ice chosen. As an example, 
under the foregoing conditions, 
if 100 pounds of dry salt is 
added to 900 pounds of ice the 
total available refrigeration is 
1,000 X 133 - 133,000 B. T. U. 
The available refrigeration per 
pound of mixture, 133 B. T. U., is taken from curve in figure 4. If 
the salt added is at a higher temperature than 32° F., say 60° 
100 
s 
s 
ffS 
\ 
s 
\ 
.90 
N 
\ 
\ 
1 
S 
N 
£ 
n 
\ 
S t 
.7S 
\ 
sx 
3 
J 
) 
/ 
o 
/ 
5 
2 
O 
S 
^eFtCSHTACrE- OF SALT 
Fig. 5. — Specific heat of common salt brine, with 
different percentages of salt. 
