4() REPORTS ON THE STATE OF SCIENCE.—1918. 
to the close relationship existing between electrical endosmose and 
cataphoresis and because of the not very surprising fact that cata- 
phoresis plays a very important part in many so-called “elecitro- 
osmotic” processes in practice, no attempt will be made to exclude 
technical cataphoresis from this discussion or to limit it strictly to 
electrical endosmose. 
DEWATERING PEAT BY ELECTRICAL ENDOSMOSE. 
The possibility of using electrical endosmose and cataphoresis in 
the removal of water from muds, pulps and jelly-like or spongy masses 
containing materials in suspension, has been considered in some 
detail during recent years, especially by Count Botho Schwerin in 
Germany. The peat bogs of the latter country and of Ireland offer 
a very great potential source of fuel provided only a sufficiently 
economical method can be devised for dewatering the material. 
Filtration and centrifuging are not applicable because of the slimy 
nature of the peat pulp, which causes an impervious layer to form 
on the filter or in the centrifuge. Attempts have been made to sub- 
mit the peat mud to stream evaporation combined with drying in the 
air. The mud as it comes from the bog contains approximately 90 
per cent. of water and to evaporate a pound of this material con- 
taining 50 per cent. of water (which can then be cut into blocks and 
dried in the air) approximately 880 B.T.U. are required. After air- 
drying the intermediate 50 per cent. material, a final product results, 
containing about 20 per cent. of moisture and possessing a calorific 
power of about 8100 B.T.U. per pound. As one pound of the 
original mud yields rather less than one-eight pound of dried peat, 
yielding not more than 1000 B.T.U., it is evident at once that the 
problem cannot be solved by a direct dehydration process such as 
the one outlined above. But it might be possible in such a duplex 
process to substitute electro-osmose for the preliminary evaporation 
and so either to remove mechanically a large part of the water or 
else to concentrate the suspended: particles in the pulp by causing 
them to migrate by cataphoresis to the electrodes. It is well to bear 
in mind, in this connection, that the electro-osmotic process cannot 
possibly dry? anything; it can at best remove water only to the 
extent that filter presses or centrifuges do. 
Count Schwerin was granted his first British Patent® in 1900. 
Various types of apparatus were disclosed, in all of which the peat 
was treated between a suitable anode and a perforated cathode. On 
passing a direct current between the electrodes, water was forced 
out of the spongy or semi-liquid mass and escaped through the 
perforations in the cathode. At the same time some of the sus- 
pended peat migrated to the anode and formed there a fairly dense 
layer. Schwerin called this the “motorial” action of the electric 
current. 
He next patented an apparatus‘ consisting of a series of superposed 
horizontal partitions, ccrrugated to allow liquids to flow away, and 
supporting boxes containing raw peat. These boxes were filled with 
? Cf. Nernst and Brill: Verh. Deutsch. phys. Ges., 11, 112 (1909). 
3 Brit. Pat. 12431 (1900). 
4 Brit, Pat., 22301 (1901). 
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