The electrolytical action
is of course easily understood, but the chemical changes that take place
need an explanation. At the positive pole, hypochlorite of iron seems to
be formed at first, but this is quickly changed into a protochloride,
and as at the negative pole an alkaline reaction takes place, the iron
salt is precipitated in the form of the ferrous hydrated oxide, together
with the organic matters in suspension and solution. Owing to the
carbonates that are always present in sewage, ferrous carbonate is also
formed.
The success of these laboratory experiments led me to a trial of the
process on a larger scale, for hitherto only a gallon at any one time
had been treated.
Small brick tanks were erected at my wharf at Peckham and iron
electrodes fitted to them.
Wrought iron plates were fixed about an inch apart, and connected in
parallel in the tanks, forming one big cell. Sewage to the amount of
about 200 gallons was run into the electrode tank and then treated, the
results being so satisfactory that larger works were erected, when a
supply of sewage equal to 20,000 gallons an hour could be obtained.
Pages:
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147