Tramfloc® Polymers
offer many benefits for the plant and process manager and
owner. We can achieve lower dosage levels which will produce
lower flocculation costs. A faster settling rate can be developed
which will increase system throughput. We can help produce
a denser underflow which will capture more TSS and thereby
yield higher sludge cakes and lower turbidity supernatant.
This will allow for a higher product quality where the clarification
process is critical to manufacturing a low or no solids' product.
The
performance and efficiency of Tramfloc Flocculants are strongly
influenced by the selection and application techniques of
the chosen product. We recommend specific procedures to
evaluate and select Tramfloc polymers tested in your laboratory.
This section explains how to prepare and apply solutions
of Tramfloc polymers to help ensure accuracy of results
and conclusions, ease of testing and cost effectiveness
of the Tramfloc Flocculant applied in your liquid/solids
separation process. The solubility rate varies with each
type and grade of Tramfloc polymer based on its individual
ionic charge, characteristics and molecular weight. In general,
the higher the weight, the longer it will take to make a
reliable testing solution.
Emulsion
and dispersion grades of polymer require adequate and effective
wetting in order to be of maximum value in the process application.
The initial wetting of the polymer with water should be
done in a high-shear condition environment of ephemeral
duration. In-line static mixers, elaborate make down units
and adding polymers to the vortex created by an agitator
in a mixing tank are suitable methods.
If
testing solution grade polymers such as the Tramfloc 520-530,
620-630, and 720-740 series products described elsewhere
on the Tramfloc, Inc. web site, dilution serves only to
reduce viscosity so that the solution will mix completely
with the process stream to be treated. Merely good agitation
will make a workable solution due to the high miscibility
of Tramfloc solution polymers.
When
producing stock solutions of polymers, they should be prepared
at the maximum practical solution strength as dictated by
their final solution viscosity which will be about 0.5%.
Care should be taken to determine the minimum and maximum
solution strength. In general, better performance is obtained
from lower strength stock solutions of polymer. In dewatering
applications, however, dilute solutions may be undesirable.
Stock
solution tanks are normally fitted with a low speed impeller
on the agitator shaft. The impeller should be large enough
to turn over the viscous polymer solution. For very large
stock solution tanks, an agitator with dual impellers should
be used. The polymer concentration in the stock tank should
always be known. It is a general rule of thumb that the
more dilute a stock solution is, the shorter its shelf life.
Stock solutions should not be stored more than one day.
Laboratory testing should be conducted if the dilution water
supply is extremely hard or contains metal cations.
Once
the stock solution has been prepared, it can be damaged
by high shear conditions. Therefore, superfluous points
of high shear should be eliminated and low shear gear or
progressive cavity pumps are helpful. The optimum addition
point or points for a stock solution should be determined
during in-plant trials. The solution addition point is frequently
the position at which the process or waste stream is fed
into a clarifier or thickener feedwell. The addition of
polymer solution in this point of high turbulence usually
produces optimum results. Laboratory testing may help indicate
whether or not multiple stock solution feed points should
be considered. Efficient mixing should follow each separate
addition point. When treating concentrated process or waste
streams, as typical of filters or centrifuges, a mild mixing
stage is usually required. This means that specially designed
low speed mixing chambers should be used when conditioning
the stream with polymer solution. Polymer solutions fed
to centrifuges are normally injected inside the machine
or into the feed line.
POLYMER
TESTING PROCEDURES FOR CLARIFICATION APPLICATIONS
1.
It is advantageous to perform bench scale evaluations in
order to reduce the number of potentially successful Tramfloc
Flocculants as far as possible. Charge four drops of each
Tramfloc emulsion polymer to be evaluated to 100 ml of warm
tap water. Return the excess polymer to the sample bottle.
You would do well to use 7 or 8 oz. clear plastic cups to
contain the dilution water which will be mixed with the
Tramfloc polymer. Draw water repeatedly into the syringe
from the 100 ml of dilutant after discharging the four drops,
about 20 times, until the polymer has been well dispersed
into the solution and it has become homogenized. That ratio
will produce a 0.1 % polymer solution. Mark each of the
solution containers with the Tramfloc polymer product designation.
We suggest that the samples stand quiescently for 60 minutes
in order to allow the tightly wound polymer chains in Tramfloc
polymers to uncoil before they reach their full effectiveness.
2.
If you are evaluating Tramfloc dry polymers, weigh 100 mg
of polymer and charge very slowly with 3 ml. of isopropanol,
acetone or ethanol to initially wet the granules. Then slowly
charge 100 ml of tepid tap water. Add the granules almost
singly so that they fall into the vortex of the water which
is being stirred rapidly, if none of the aforementioned
solvents are available. That ratio will produce a 0.1 %
polymer solution. Place the beaker on a heated magnetic
stirrer for optimum results. Mix until all the granules
have disappeared into a homogeneous solution without lumps
or fish eyes. Reduce the speed to 50 rpm and after as much
as 60 minutes of stirring, a viscous and homogeneous solution
should have been formed. The water and granules may be mixed
vigorously in a stoppered flask for several minutes before
quiescence. Each particle of dry polymer must be wetted
with water to insure that a reliable testing solution has
been prepared. Allow the solution to uncoil fully by causing
the solution to stand quiescently for 120 minutes. Each
solution container should be marked with the Tramfloc polymer
product number.
3.
Charge 1000 ml of untreated sample into a beaker and place
in a jar tester. Be sure that the sample you have selected
is representative of the plant process, especially with
respect to pH, temperature, TSS, homogeneity, biological
activity etc. A standard gang stirrer works effectively.
Stir samples at high speed while charging the polymer solutions
to be tested. Set the stirrer speed at 100-150 rpm and after
3-8 minutes, rapidly charge the desired amount of polymer
solution. Then reduce the stirrer speed to 40-50 rpm for
1-2 minutes. Stop the stirrer and observe results for up
to 10 minutes. One ml of polymer solution charged to 1.0
L of sample yields a 1.0 ppm polymer feed rate.
4.
Initially apply dosages of 1-10 ppm. If no performance is
observed, increase the dosage by 5 ppm until you have tested
dosages up to 100 ppm. Thereafter, increase dosages by 100
ppm up to 1000 ppm. It is sometimes necessary to adjust
pH, as in the case of MeOH precipitation. Tramfloc coagulants
may also be required when the flocculant dosages do not
reveal desired settling.
5.
Continue testing samples until you have applied all Tramfloc
polymer solutions in all the appropriate dosage ranges.
6.
Observe which sample(s) had the fastest solids' settling
rate, largest floc, densest floc mass, clearest supernatant.
Congratulations! You have just selected the Tramfloc polymer
which should be used to clarify your waste stream. You may
now schedule a trial application of the new polymer. Call
us with any questions which may arise and please advise
us of your final testing results.
POLYMER
TESTING PROCEDURES FOR DEWATERING APPLICATIONS
1.
Follow steps one and two as per the above section to produce
polymer solutions for testing purposes.
2.
Charge about 100 ml of sludge to be dewatered into a new
7 or 8 oz. clear plastic cup, marked with the Tramfloc polymer
to be tested. Add one full syringe of the Tramfloc polymer
solution to the sludge and then pour the treated sludge
into another clean plastic cup. Transfer the treated sludge
sample and back and forth to the original container, four
or five times to completely mix the Tramfloc polymer solution
and the sludge sample. Experiment with various dosages as
the results indicate.
3.
Set the conditioned sludge container aside and repeat the
entire procedure until you have a 100 ml container of sludge,
each treated with a different Tramfloc dewatering polymer.
4.
Observe which sample has the largest and densest floc particles,
with the clearest supernatant and the largest water cavities
around the floc chunks. You have just selected the Tramfloc
polymer which should be further tested in a trial application.
Tramfloc
Polymer Performance
Every
year, hundreds of millions of dollars are spent on polymers
for optimization of water and wastewater treatment liquid/solids
separations.
Obviously,
there are several very important reasons for these vast
expenditures:
Aesthetics
- People do not want turbid water flowing from their taps
or improperly treated wastewater dumped into waterways.
Simply stated, pollution is ugly.
Economics
- Wastewaters may contain a small amount of a valuable product
that can be reclaimed by liquid/solids separation. Or, in
areas of limited water supply, the water itself can actually
be the valuable commodity that must be reused as many times
as possible. The use of flocculants to provide an efficient
separation of solids from water may be economically justified
if the value of the recovered product offsets the cost of
the polymer.
Public
Health/Process Needs
- Waters and wastewaters very often contain undesirable
solids, such as heavy metals, colloidal organics, hardness
salts, etc., that usually comprise a very small percentage
of the total flow. These waters must be treated to meet
individual plant, state, and federal requirements before
they are used or discharged. The basic function of flocculants
is to increase efficiency of clarification and solids concentration
operations.
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The
Advantages Of Tramfloc Fluid Flocculants |
|
Over
Powdered Flocculants |
Over
Other Fluid Flocculants |
- Polymer
solutions prepared quickly - solutions are made
in half the time saving many man hours of labor
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- Cost
performance - a decrease in treatment costs can
be expected with a corresponding increase in treatment
efficiency
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- Ease
of operation - conveniently handled, stored, measured,
and pumped; problems with broken bags and polymer
lumps from humid conditions are eliminated
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- Lower
addition levels - due to a higher active solids
content (twice the polymer concentration of most
emulsion flocculants); lower inventory, shipping,
and handling costs are obtained
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- Higher
solution concentrations can be prepared - mixing
and labor costs are reduced since fewer batches
of solutions need be prepared each day
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- Higher
reactivity - molecular weight of polymer molecules
is significantly higher than emulsion polymers
available today, therefore larger flocs are formed
at relatively low addition levels
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- Complete
solutions are easily prepared - no waste caused
by undissolved "fisheyes" so accurate
addition is achieved and plant results can be
more accurately predicted by bench monitoring
tests
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- Superior
shelf life - 9 months or better is typical, comparing
favorably against emulsion polymers with typical
shelf lives of 6 months
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- Dust
problems are eliminated - no more hazardous (slippery)
conditions on floors and equipment
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- Product
line versatility - a complete
range of ionic charges is available for the first
time from a single supplier
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Once
a liquid/solids separation problem has been identified,
a course of action must be established to achieve the desired
results. Very often prior experience is available to help,
but there is no substitute for the information obtained
from a first-hand bench test. Proper testing enables one
to select the best product(s) quickly by visual observations,
determine approximate dosages, and experiment with different
approaches without danger of plant upset.
Tramfloc's
fluid flocculants can be easily evaluated and demonstrated.
Various test methods are available, as illustrated above,
to screen polymers in the many types of applications and
equipment found in water and wastewater treatment plants.
For example, the most common test for polymer evaluations
is the jar test. Effects of chemical dosage, mixing time,
and addition sequence can be observed and compared side-by-side
with the current treatment program or any other proposed
changes. In addition to jar tests, settling tests using
graduated cylinders can also be run to determine the effect
of polymer dosage on floc size, settling rate, and sludge
compactness. Lastly, Buchner funnels and leaf filters can
be used in sludge dewatering applications to predict performance
on either vacuum filters or belt presses. All of these tests
can be used to screen polymers and program changes, as well
as monitor the effectiveness of the treatment program in
the plant on a routine basis.
Tramfloc
Technical Representatives, located nationwide, are extensively
trained to evaluate different polymers as well as various
addition levels to determine the chemical program needed.
We would be happy to extend this service to you to optimize
your treatment program.
| Tramfloc
Fluid Flocculants |
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Features
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Benefits
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1. Highly concentrated |
- Lower
addition levels
- Lower
inventory, shipping, and handling costs
|
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2. Very high molecular weight |
- Ability
to attract more suspended solids to each polymer
molecule - further decrease in addition level
- Larger
flocs
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3. Improved stability/minimal water content |
- Performance
unaffected in storage for at least 9 months
- No
gel formation in unopened drums
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4. Liquid |
- Conveniently
handled
- Quick
and complete solution preparation - accurate dosage
achieved
- No
dust problems
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5. Totally organic |
- Compatible
with activated sludge
- Complies
with landfill's heavy metals restrictions
- Biodegradable
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CONCENTRATION
+ MOLECULAR WEIGHT + STABILITY =
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Gravity
Clarification
This
is the most commonly used method of suspended solids removal
in water and wastewater treatment. In an industrial plant
whose influent quality changes or whose treatment system's
capacity is being exceeded due to an increased process water
demand or wastewater load, flocculants are used to agglomerate
suspended solids into larger, faster settling masses, thus
counteracting the increased hydraulic load or variable settling
characteristics. In addition to increasing the speed of
the liquid/solids separation, flocculants are also capable
of increasing the separation efficiency by capturing solids
that carryover into the effluent as well as contributing
to the stability of the sludge bed.
Air
Flotation
Certain
types of solids have a tendency to float or to settle at
extremely slow rates even when flocculated. Flotation equipment
takes advantage of the natural buoyancy of these solids
by floating them instead of allowing them to settle. Flocculants
are used to form large macroflocs which can be easily transported
to the surface by the rising air bubbles and subsequently
removed. As in the case of gravity clarifiers, the use of
flocculants can increase throughput capacity (by increasing
particle rise rate) and prevent suspended solids carrying
through into the effluent.
Sludge
Dewatering
Very
often, sludge has to be concentrated as much as possible
to save hauling costs and meet the minimum solids restriction
imposed by the local landfill. In a large majority of sludge
handling applications, the dewatering processes are greatly
improved through chemical conditioning with flocculants.
Higher sludge solids, cleaner filtrates or centrates, and
increased throughputs on equipment very often result. Through
flocculation particle size is increased, producing large
flocs that are resilient to the physical stresses imposed
by sludge dewatering equipment. As a result of increasing
particle size, more sludge-bound water is released and the
solids capture rate is much higher, reducing the solids
load to the front end of the plant.
Chemical
Description and Handling
Tramfloc
fluid flocculants are Tramfloc's water-soluble, high molecular
weight, synthetic organic polymers developed specifically
for use as flocculants in water and wastewater treatment.
Detailed
descriptions of Tramfloc fluid flocculants and their applications,
as well as specific recommendations for storage, handling
and feeding are available in our Material
Safety Data Sheets.
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