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Fluidized
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Bed
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and
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Dissolved
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Oxygen Measurements
Procedure
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Measurements h2. Procedure {float:right|border=2px solid black}[!SandFilterSetup1.png|width=500px!|Initial Sand Filter Setup] h5. Initial sand filter experimental setup {float} |
These
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are
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the
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results
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of
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the
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first
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several
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experiments
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run,
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with
...
the
...
...
...
...
.
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This
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setup
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consisted
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of
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the
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flow
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accumulator
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and
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vertical
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glass
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filter
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column.
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A
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dissolved
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oxygen
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(DO)
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probe
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in
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the
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flow
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accumulator
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recorded
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the
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dissolved
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oxygen
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concentration
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of
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the
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inflowing
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tap
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water.
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The
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flow
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rate
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and
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temperature
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of
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the
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water
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was
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monitored
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by
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a
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pressure
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sensor
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and
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temperature
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probe
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inside
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the
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flow
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accumulator
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and
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controlled
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by
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valves
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on
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the
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hot
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and
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cold
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water
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lines.
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These
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valves
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were
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opened
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and
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shut
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by
...
the
...
program
...
...
...
.
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Once
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the
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water
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had
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run
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through
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the
...
filter
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column,
...
it
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was
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collected
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in
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a
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small
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beaker
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containing
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another
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DO
...
probe,
...
which
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recorded
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the
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dissolved
...
oxygen
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concentration
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of
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the
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outflowing
...
water.
...
Results
The first experimental run used glass beads as the filter media and a flow rate of 200 mL/min.
...
The
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unsuspended
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filter
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depth
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was
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32
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cm,
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and
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the
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temperature
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was
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held
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at
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a
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constant
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20
...
degrees
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Celsius.
...
...
...
illustrates
...
the
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change
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in
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dissolved
...
oxygen
...
that
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occurred
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over
...
time,
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measured
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by
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DO
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probes.
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The
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yellow
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line
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represents
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the
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DO
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concentration
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of
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the
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inflowing
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tap
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water,
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and
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the
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blue
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line
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represents
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the
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DO
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of
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the
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outflowing
...
water.
| Anchor | ||||
|---|---|---|---|---|
|
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{anchor:Figure 1} {float:right|border=2px solid black}!DO vs. Time, 200mLmin.png|width=500px! h5. Figure 1: Initial results obtained using glass beads at\\a flow rate of 200 mL/min and a filter depth of 32 cm. {float} |
While
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the
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inflow
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DO
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concentration
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was
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about
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9mg/L,
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the
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outflow
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was
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roughly
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11
...
mg/L.
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Overall,
...
...
...
shows
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that
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the
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outflow
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DO
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concentration
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was
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measured
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as
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higher
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than
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the
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inflow
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concentration.
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This
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was
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inconsistent
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with
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what
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we
...
predicted.
...
Though
...
it
...
was
...
possible
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that
...
this
...
setup
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would
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have
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no
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effect
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on
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the
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the
...
DO
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of
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the
...
water,
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the
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DO
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should
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not
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be
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able
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to
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increase
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inside
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the
...
system.
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We
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found
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that
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this
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was
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most
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likely
...
due
...
to
...
the
...
error
...
in
...
the
...
DO
...
probes,
...
which
...
we
...
found
...
were
...
not
...
functioning
...
properly.
...
To
...
download
...
the
...
data
...
file
...
for
...
...
...
,
...
click
...
Conclusion
We concluded that we needed to purchase a new, more reliable DO probe to measure the oxygen concentration, or else we needed to find another method to measure the DO concentration. We decided to try out the sugar test in future experiments, which involves adding sugar to the outflowing water to see if bubbles form (if yes, then the water is still supersaturated). We also modified our setup to include a bubble collector in order to directly observe the amount of gas leaving the water. Together, the sugar tests and the new setup comprised the second phase of our experiments, which is completely described here.