21.
In diatomite fiItration, the diatomaceous earth's irregularity in size and shape
enables the particles to be:
a. Highly porous and separate quickly.
b. Highly porous and cling together.
c.
Separate quickly and become rigid.
d. Separate slowly and become hard.
22.
What are three of the common methods of disinfection?
______________________.
______________________.
______________________.
23.
Which is the most field expedient method of disinfection?
___________________.
24.
What type and form of coal are sometimes used to replace the sand in rapid sand
fiItration?
___________________.
25.
The erdlator incorporates which of the following processes and/or equipment?
a. Plain sedimentation.
b. Sodium aluminate as a coagulant.
c.
FiItration by means of a slow sand fiIter.
d. Chemical pretreatment combined with disinfection.
e. Continuous flow treatment, using an up flow clarifier.
MD0160
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