18
Biological Cleaning.
Biological cleaning is used
on the parts that come in contact with the
distillate (such as, the distilled water side of the
condenser, or the distilled water transmission
tubing) to remove any biological contamination
from the affected part. This may be accomplished
as follows:
1.
Immerse the part in an isopropyl alcohol
or a mild detergent (not containing
bleach) solution overnight. Do not rinse
the part with water after cleaning. Drain
parts before reassembly.
2.
After the still is reassembled and has
operated for 30 minutes to flush, reduce
the cooling water flow rate with the cool-
ing water throttling valve until steam
issues from the condenser vent at least
12 inches. Operate the still in this
manner for 30-60 minutes. Ventilate the
room during this operation.
Disassembly for Cleaning
The frequency of cleaning will depend upon the
purity of the water being used. For example, the
evaporator should require infrequent cleaning if it
is fed partially purified water; however, the
cooling water side of the condenser will have to
be cleaned at more frequent intervals due to the
fact that raw water is flowing through it and it will
scale up sooner. The still should be inspected at
frequent intervals until cleaning intervals are
determined. Disassemble, inspect, and clean the
still as follows:
M
AINTENANCE AND
S
ERVICING
Warning
Avoid splashing the isopropyl
alcohol solution on open cuts.
Caution
Do not use chlorine bleach for
biological cleaning. The chlorine
will interact with and damage the
tinned surfaces.
