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...
Author:
...
AguaClara
...
Pilot
...
Plant
...
Spring
...
'08
...
Sub-Team
...
Sections
...
on
...
Testing
...
of
...
the
...
Tapered
...
Flocculator
...
were
...
written
...
by:
...
- Rebecca
...
- Thompson:
...
- rnt3@cornell.edu
...
- Narayana
...
- Pappu:
...
- nvp4@cornell.edu
...
Developing
...
Turbidity
...
Profiles
...
along
...
the Flocculator
Profile Test Procedure
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Flocculator h4. Profile Test Procedure {float} {anchor:flow path top view}[!Pilot Plant^3.jpg|width=200px!|Pilot Plant^3.jpg] h5. Picture of the Flocculator set-up. {float} |
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{float}
{anchor:flow path top view}[!Pilot Plant^picture1.jpg|width=200px!|Pilot Plant^picture1.jpg]
h5. Experimental Set-up of the Tube Settler Placement.
{float}
|
The
...
purpose
...
of
...
this
...
experiment
...
was
...
to
...
develop
...
a
...
profile
...
of
...
flocculation
...
at
...
different
...
places
...
along
...
the
...
flocculator.
...
In
...
order
...
to
...
do
...
this,
...
we
...
moved
...
the
...
tube
...
settlers
...
to
...
different
...
points
...
along
...
the
...
length
...
of
...
the
...
flocculator
...
and
...
tested
...
the
...
turbidities
...
of
...
the
...
water
...
after
...
it
...
passed
...
through
...
the
...
tube
...
settler
...
and
...
reached
...
the
...
turbidimeter.
...
In
...
Experimental
...
Set-up
...
of
...
the
...
Tube
...
Settler
...
Placement
...
above,
...
you
...
can
...
see
...
a
...
schematic
...
of
...
the
...
experimental
...
set-up.
...
A
...
photograph
...
of
...
the
...
same
...
set-up
...
is
...
also
...
shown.
...
The
...
experiment
...
has
...
three
...
parts,
...
A,
...
B,
...
and
...
C,
...
each
...
lasting
...
for
...
45
...
minutes.
...
During
...
the
...
experiment,
...
the
...
location
...
of
...
tube
...
settlers
...
2
...
and
...
3
...
were
...
moved
...
to
...
different
...
places
...
along
...
the
...
flocculator
...
as
...
shown
...
above.
...
Turbidimeter
...
1
...
was
...
always
...
testing
...
the
...
incoming
...
water,
...
and
...
turbidimeter
...
4
...
was
...
always
...
testing
...
the
...
turbidity
...
of
...
the
...
water
...
at
...
the
...
end
...
of
...
the
...
flocculator
...
(location
...
4
...
above).
...
Along
...
with
...
moving
...
tube
...
settlers
...
2
...
and
...
3,
...
we
...
emptied
...
tube
...
settler
...
4
...
of
...
water
...
between
...
parts
...
A,
...
B,
...
and
...
C
...
of
...
the
...
experiment.
...
This
...
is
...
because
...
when
...
the
...
tube
...
settler
...
is
...
filling
...
with
...
water,
...
plug-flow
...
conditions
...
exist
...
in
...
which
...
velocity
...
gradients
...
cannot
...
develop,
...
and
...
flow
...
up
...
the
...
tube
...
settler
...
is
...
more
...
even.
...
So,
...
by
...
emptying
...
tube
...
settler
...
4
...
of
...
water,
...
we
...
ensured
...
that
...
the
...
potential
...
effects
...
of
...
this
...
condition
...
in
...
the
...
tube
...
settler
...
were
...
even
...
across
...
all
...
the
...
tube
...
settlers.
...
Likewise,
...
when
...
performing
...
the
...
data
...
analysis
...
after
...
the
...
experiment,
...
we
...
found
...
an
...
increase
...
in
...
the
...
turbidity
...
to
...
unreasonably
...
high
...
levels
...
(on
...
the
...
order
...
of
...
100
...
NTU)
...
for
...
about
...
10
...
minutes
...
after
...
moving
...
the
...
tube
...
settlers.
...
This
...
was
...
because
...
the
...
air
...
in
...
the
...
tube
...
settlers
...
which
...
was
...
being
...
pumped
...
through
...
the
...
turbidimeters.
...
Therefore,
...
only
...
the
...
data
...
at
...
the
...
end
...
of
...
each
...
part
...
of
...
the
...
experiment
...
was
...
used
...
(approximately
...
after
...
10
...
minutes
...
of
...
running).
...
The
...
removal
...
of
...
the
...
air
...
can
...
be
...
easily
...
observed
...
in
...
the
...
data
...
when
...
the
...
system
...
appears
...
to
...
have
...
reached
...
a
...
steady-state.
...
Results
...
from
...
Profile
...
Testing
...
of
...
Tapered
...
Flocculator
...
Set-up
...
Spring
...
'08
| Wiki Markup |
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{float}
{anchor:flow path top view}[!Pilot Plant^picture2.jpg|width=200px!|Pilot Plant^picture2.jpg]
h5. Turbidity Profile with Average Incoming Turbidity at 2 NTU.
{float} |
| Wiki Markup |
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{float} {anchor:flow path top view}[!Pilot Plant^picture3.jpg|width=200px!|Pilot Plant^picture3.jpg] h5. Turbidity Profile Ratio with Average Incoming Turbidity at 2 NTU. {float} |
| Wiki Markup |
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{float}
{anchor:flow path top view}[!Pilot Plant^picture4.jpg|width=200px!|Pilot Plant^picture4.jpg]
h5. Turbidity Profile with Average Incoming Turbidity at 7.5 NTU.
{float} |
| Wiki Markup |
|---|
{float} {anchor:flow path top view}[!Pilot Plant^picture5.jpg|width=200px!|Pilot Plant^picture5.jpg] h5. Turbidity Profile Ratio with Average Incoming Turbidity at 7.5 NTU. {float} |
| Wiki Markup |
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{float}
{anchor:flow path top view}[!Pilot Plant^2.jpg|width=200px!|Pilot Plant^2.jpg]
h5. Combined Turbidity Profiles from Three Experiments.
{float}
|
In
...
figure
...
the
...
Combined
...
Turbidity
...
Profiles
...
from
...
Three
...
Experiments
...
graph,
...
it
...
can
...
be
...
seen
...
that
...
a
...
general
...
trend
...
exists
...
in
...
which
...
the
...
turbidities
...
taken
...
from
...
the
...
end
...
of
...
the
...
tube
...
settlers
...
first
...
spike
...
at
...
the
...
beginning
...
of
...
the
...
flocculator
...
to
...
about
...
2
...
times
...
what
...
they
...
were
...
in
...
the
...
incoming
...
water.
...
Then,
...
they
...
take
...
a
...
rapid
...
dive
...
to
...
a
...
fraction
...
of
...
the
...
original
...
turbidity.
...
The
...
most
...
likely
...
reason
...
for
...
this
...
is
...
the
...
formation
...
of
...
flocs
...
which
...
are
...
not
...
large
...
enough
...
to
...
settle
...
in
...
the
...
tube
...
settlers
...
at
...
the
...
beginning
...
of
...
the
...
flocculator
...
but
...
are
...
large
...
enough
...
to
...
greatly
...
increase
...
the
...
deflecton
...
of
...
light
...
in
...
the
...
turbidity
...
meters.
...
Later
...
in
...
the
...
flocculator,
...
larger
...
flocs
...
form,
...
and
...
these
...
have
...
a
...
settling
...
velocity
...
of
...
greater
...
than
...
10
...
m/day.
...
Therefore,
...
they
...
settle
...
in
...
the
...
tube
...
settlers
...
and
...
do
...
not
...
add
...
to
...
the
...
turbidity
...
in
...
the
...
turbidimeters.
...
It
...
appears
...
that
...
a
...
trend
...
also
...
exists
...
towards
...
the
...
peak
...
turbidity
...
happening
...
earlier
...
in
...
the
...
flocculator
...
when
...
incoming
...
turbidity
...
was
...
high,
...
and
...
later
...
in
...
the
...
flocculator
...
when
...
turbidity
...
was
...
lower.
...
This
...
result
...
suggests
...
that
...
the
...
flocculator
...
is
...
more
...
effective
...
when
...
turbidities
...
are
...
higher.
...
This
...
is
...
consistent
...
with
...
the
...
expectation
...
that
...
the
...
collision
...
rate
...
is
...
proportional
...
to
...
the
...
floc
...
volume
...
fraction,
...
φ
...
floc.
...
However,
...
the
...
settled
...
water
...
turbidity
...
from
...
the
...
end
...
of
...
the
...
flocculator
...
was
...
lower
...
when
...
incoming
...
water
...
was
...
lower.
...
The
...
outgoing
...
turbidity
...
was
...
0.9
...
NTU,
...
1.3
...
NTU,
...
and
...
1.8
...
NTU
...
for
...
the
...
trials
...
where
...
the
...
incoming
...
turbidity
...
was
...
2.0,
...
2.5,
...
and
...
7.5
...
NTU,
...
respectively.
...
It
...
is
...
important
...
to
...
examine
...
the
...
absolute
...
turbidity
...
at
...
the
...
outgoing
...
points
...
because
...
this
...
is
...
the
...
parameter
...
that
...
determines
...
the
...
effectiveness
...
of
...
chlorine
...
and
...
overall
...
safety
...
of
...
the
...
water
...
produced
...
by
...
our
...
system.
...
We
...
need
...
to
...
achieve
...
water
...
that
...
is
...
consistently
...
safe
...
to
...
drink
...
because
...
the
...
reliability
...
of
...
our
...
water
...
treatment
...
plants
...
affects
...
the
...
health
...
of
...
our
...
beneficiaries
...
on
...
a
...
daily
...
basis.
| Wiki Markup |
|---|
\\ {float} {anchor:flow path top view}[!Pilot Plant^picture6.jpg|width=200px!|Pilot Plant^picture6.jpg] h5. Turbidity Profile vs. Gθ. {float} |
The
...
graph
...
above
...
shows
...
the
...
flocculation
...
profile
...
versus
...
Gθ
...
as
...
calculated
...
with
...
the
...
model
...
developed
...
by
...
Leslie
...
Campbell
...
of
...
the
...
Design
...
Team.
...
This
...
model
...
is
...
as
...
follows:
...
| Include Page | ||||
|---|---|---|---|---|
|
...
|
...
|
...
Where
...
totbaffle
...
is
...
the
...
number
...
of
...
baffles
...
before
...
the
...
testing
...
plant,
...
Qplant
...
is
...
the
...
flow
...
rate
...
of
...
100
...
L/min,
...
and
...
FlocTankwidth
...
was
...
the
...
width
...
of
...
the
...
flocculator
...
sections,
...
or
...
12
...
inches.
...
The
...
other
...
parameters
...
were
...
set
...
as
...
follows:
...
Π
...
cell =
...
2,
...
kb
...
=3,
...
and
...
the
...
viscosity
...
of
...
water
...
was
...
1
...
*
...
10
...
^-6
...
m
...
^2/s.
...
By
...
examining
...
this
...
graph,
...
we
...
can
...
see
...
that
...
the
...
total
...
Gθ
...
of
...
this
...
set-up
...
was
...
about
...
5000,
...
which
...
similar
...
to
...
the
...
Gθ
...
of
...
the
...
flocculator
...
at
...
Ojojona,
...
which
...
is
...
about
...
4000.