User Manual

C. EXPERIMENT 1 - FILTERING
Warning: The filter column is not intended as a filtering device
for drinking water. Do not drink the filtered water.
In this experiment, you use the assembled filter column
from the kit to purify water. The various filters in the column
remove impurities from the water.
You will need: 4 x filter sections, 4 x filter plugs, filter base,
soft wax, bag of active carbon, bag of sand, bag of gravel,
filter paper. (Remarks: you need only one unit of those filters
for setting up the filter column. Leave the other two as spare
supplies for future experiments.)
Also needed from home (not included in kit): some soil from
a clean source (e.g. pot plant or flower-bed), cooking oil, a
glass (any size) and a glass (preferably transparent) whose
diameter is smaller than the round filter base.
Constructing the filter column
1. The filter plugs are specially designed for regulating the
speed of water flow inside the column. There are six arches
in the rim of each filter plug. Take two of the plugs and fill
four arches in each one with
a very small piece of wax,
leaving two open arches.
These two plugs will be used
in the filter sections which
contain sand and active
carbon. They will reduce the
speed of flow through the
sections, allowing the sand
and active carbon to achieve their best filtering effect.
2. Fit the filter plugs into the holes in the bottom of each
filter section. You may need to push the plugs into place with
a pen. You should have two sections with plugs with six open
arches and two sections with plugs with two open arches.
2 3
3. Clean the gravel, sand and active carbon separately before
filling in the filter sections. Simply place each of the materials
in a small container (don’t mix the materials). Rinse them
with clean water a few times. This will remove any dust
sticking to them.
4. Put the sand and active carbon into the filter sections with
filter plugs of two open arches, and the filter paper and gravel
into the sections with filter plugs of six open arches.
5. Put the filter base on a table. Put the filter sections onto
the base in the following order from the bottom: filter paper,
active carbon, sand, and finally gravel. Make sure each
section snaps into place on the one underneath.
6. Stand the completed filter column on top of the glass.
Preparing the artificial “dirty water”
Half fill a small glass of water. Add the soil and oil to it and
stir to make a brownish coloured mixture. This will be the
“dirty water” for the filtering experiment. (Always wash your
hands after handling soil or the dirty water.)
Doing the experiment
Pour some artificial “dirty water” mixture into the top of the
filter column VERY SLOWLY. The water will trickle slowly down
through the filters. For the best results, the water should be
moving between the filter sections drop by drop.
How clean is the water that runs into the glass?
Gravels
Gravels
Oil
Mud
Sand
Sand
Active
carbon
Active
carbon
Filter
paper
Filter
paper
X 2 X 2
Artificial “dirty water”
Soft
Wax
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