In article , Keith
wrote:

What's untrue? That a racor element will clog up very fast if you have dirty
fuel?
***** Not in comparison to a cylindrical paper roll. Or do you mean
that the efficiency of a toilt paper roll is soooooo low that it
captures virtually nothing except very large visible particles that is
continues to unload at the same rate that it captures.... and all the
while buirning up amperage to run the pump to overcome the high CLEAN
differential pressure required. If a filter plugs, then it did its job
!!!!!!!!!! Its not the job of a filter to pass particulate at its
designated retention rating. Whats the retention rating of toilet
paper ??????? .... why doesnt it plug up when hit with a slug of
particles???? Have any data on the residual particle level in a tank
after X passes through the 'filter'.
Actually the "surface area" would be much greater in a paper towel,
***** How is the surface of a pleated filter less than the surface of a
cylinder?. Doesnt make sense. A typical pleated 2.5" dia. X 10"
filter has a surface area of 5 to 6 sq. ft. A toilet paper roll of
4.5" dia X 4" long has a surface of 0.4 square ft. Thats 12 to 15
times MORE surface area for the pleated for a normal recirc.
installation.
since
you are filtering through from one end to the other, while the racor only
filters through the pleated surface.

By the way, what do you mean by "de-polarize"?
***** Electropolization of the long chain agglomerated macro-molecules
..... same thing that probably allows a woman to get pregnenat once a
month. ...
Are you saying that slime is
magnetic?
*****NO
Or that they are polar molecules, like water?
***** Yes they can be
Maybe that's how
those algae-x things work!
Yes....But, I have NO idea (nor interest) about algae-x ... if it
works or not :-)
Can you quote the specs for all those test methods you mentioned for a
Racor... any racor/filter combination? Pick one.
Any 'reliable' filter manufactuerer uses (and can document compliance
to) the following data to compare filters. Those that cant or wont are
usually 'shysters' or are totally ignorant of filtration and offer
ratings that are ENTIRELY ARBITRARY (a kind word for: liars).
The test is a universal standardized test adopted ASTM. The test
curently used was developed about 1960 for comparisons of filtration
efficiency by the Oklahoma State University - called the OSU F2
test-stand (and defines a standardized test contaminent to establish
equal comparisons between filtration media) - its THE industry standard
for coarse filtration. A Racor type or other resinated pleated paper
will usually test out to a 'beta value' (log of upstream challenge to
downstream challenge between a beta value of 1000 - meaning about
95-98% weight efficiency. An unresinated paper upon increasing
differential pressure will ***unload*** at approximately a beta value
of 50 (less than ~25% efficiency). I am deeply involved in filtration
engineering and do consulting work that includes depth filters made of
cellulose (with binding resins). A cellulosic filter media needs a
binder for strength and sometimes the addition of Perlite to enhance
wet-strength .... or it simply compresses to stop flow OR falls apart
in the presence of water and other liquids. Commercial/Industrial
depth filters for fuel oil also sometimes include diatomaceous earth to
enhance the retention and service life .... plus the addition of
elemental starches for the absorbtion of free water (for 'trimming'
/absorbtion of water emulsion). Without a graded pore density a
cellulosic filter captures virutally ALL the particles on the surface
(cylinder). A paper made into toilet paper or paper towels is made
from very coarse fiber stock - poor permeability vs. flow AND contains
lots of small chopped fibers that they themselves are free to migrate
out of the paper matrix (particles themselves).

That a toilet paper filter works (at all) depends on LOW differential
pressure (or the cellulose compresses into a 'sludge') but does take
into account statistical particle reduction of multiple pass filtration
of recirculation mode. Its pretty false economy to have overpriced,
poorly performing/designed housings and then put in a poorly performing
'toilet paper' 'filter' that has NO certifiable retention rating, is
made from paper that is variable in density, is made from paper that is
specifically MADE TO DIGEST and FALL APART in the presence of
water/liquids. Fibers for toilet paper and paper towel rolls are NOT
arranged into a graded pore density (the retention of the upsteam
surface is larger than the downstream or exit portion of the depth of
media) such as a typical
TRUE depth filter': which means grade pore density....pores/cpature
sites get smaller as one goes deeper into the matrix. For a fixed pre
density (such a roll of toilet paper) what is not captured on the
surface can migrate all-the-way-through the 'filter. Your implication
of successive potential sucessive capture sites is only for VERY LARGE
particles as with smaller and smaller size particles the removal
mechanism of inertial impaction capture decrease logrithmically. A
roll of toilet paper will wrinkle-up into a 'little knot' when high
differential pressures are applied while UNLOADING most of the debris
that it originally captured. This 'technology' came out the
"oil-patch" in the 1920s, has been replaced by fixed pore, graded pore
density depth pads or cartridges (in the 1970s). A pleated resin bound
filter cartridge uses a vastly smaller filter housing. A pleated
paper. Typical true depth filtration in cartridge form requires
housings that are 5-10 times the size (cost) of a pleated configuration
-------- to do the same exact job.

The pleated resinated paper filter has VASTLY less resistance to flow,
has a defined retention rating, will allow the pump to deliver more
volumetric flow rate and at less amperage draw, requires smaller
housing (on an equal flow basis) @ first /installation cost, has
documented retention, flux. .... because of these advantages will
reduce the resident particles in a tank to nearly undetectable limits
****exponentially faster**** than a filter that inherently DOES NOT
FLOW and has poor retention ability, .... I guess an advantage is that
the amperage draw of such a toilet paper system can help heat the
interior of a boat in winter!

Please answer the following:
What is the collapse pressure of a toilet paper roll?
What is the particle retention rating on either an absolute basis or
'nominal' rating? How about a beta value? or do you just depends on
'dumb luck'.
What is the loss of efficiency due to the 'knife edge seals? What is
the percent of bypass at 30uM at the knife edge? 20uM, 10uM, 2uM
What is the wet strength rating?
What is the recommended flow rate of a toilet paper roll? How do you
'size' a toilet paper filter to operate at the low motive pressure of a
fuel system? Is it ....."Just BUY one and see if it works" ....
hardly!
Tell me which toilet paper mill makes a 'technical grade' of paper?
Tell again that a rolled paper filter is more efficient than a
'cartridge'. ... include the PRICE of the housing in your
evaluation/reply.
Whats the 'dirt capacity' of a to9ilet paper roll? A 2.5" dia X 10"
pleated typically has about 150 grams capacity..... an equivalent
cartridge true depth filter (in cartridge format) will have about 20-25
grams capacity.

;-)