Fuel transfer/polishing pump
In article , Len Krauss
wrote: Second step is to, while polishing, agitate fuel at bottom of tank using a small L-shaped air discharge pushed down to tank bottom on a rod or dowel and turned about as much as possible. Obviously the fuel furthest away from the discharge will get the least agitation and baffles will reduce degree of agitation for sure. But with the L-shaped discharge at the bottom and turned, disturbance will flow through baffle bottom notches. The basic idea is to get crud in suspension and moving so it can be captured by the polishing pick up and filtered out. You are correct!!!! but dont use air. Tank farms use whats known as a *sparging nozzle* to keep the tank in constant agitation. Its simply a jet of liquid that discharges into a throat of a venturi section. The velocity from the jet into the venturi 'entrains' the liquid in the bottom of tank to circulate. A sparger moves the layers on the bottom of the tank towards the top; hence, affects a mixing. (for techies amoung us, a sparging nozzle {sparger} in an 'open inlet eductor') If you use air, you generate a lot of air entrainment which can settle out and coalesce into larger and larger bubbles of air .... and block the downstream system. |
Fuel transfer/polishing pump
Nope.... I suggest a test for you
Take 25-50 grams of the finest dust/crud you can find. Dump it in upstream of a TP filter and see what happens ..... it will immediately plug - or will hardly capture anything. Change to a high surface area pleated filter dump in 25-50 grams of crud, another 25-50 grams of crud, another 25-50 grams, then another 25-50 grams, then another .... then it will plug. Take out the filter, examine .... you will find a small layer of crud on the surface. That layer is called a "filter cake". That layer of debris because the velocity throuth the 'cake' is so much smaller (than the velocity through a TP etc. roll that it does in fact flow and until the cake reaches a 'terminal' differential pressure will be the principal means of particle captu dirt filtering out other dirt. This cannot happen in a depth filter....because there is *no room for the 'cake' to form* (inside the filter). For a true depth filter, you add a filter aid (Diotomaceous earth, perlite, etc.) on a continual basis so that the deposition is controlled, the debris is contained in the cake of DE + crud. The surface of the depth filter holds the cake. If the particles get inside the depth filter it PLUGS. You can design a 'profiled' depth filter that has a graded pore density.... bigger pores on the upstream side, smaller pores on the downstream side ....and that costs about 20 times the price of a toilet paper roll ..... and also is a resin bonded cellulose matrix. Resin bonded so that the cellulose matrix desnt collapse upon itself during increasing differential pressure, doesnt fall apart if it gets wet with water, etc. In article , Brian Whatcott wrote: On Fri, 05 Dec 2003 20:02:22 GMT, Rich Hampel wrote: Please appreciate that I dont want to appear to be an arrogant know-it-all after being in on and around critical filtration/separation most of my working life ... Sounds good to me... /// Whats wrong with TP, etc. is that the material used to filter is not bonded, can digest (make more particles) in the presence of water --- thus to do the exact opposite of what you are trying to do. Perhaps a test at home would be helpful. Take a kitchen collender, A seive or funnel would also work well. Place a sheet of kitchen roll in the aperture, pleated once to fit. Spray the surface with Pam, olive oil, or soybean oil or any other oil Momma has on hand. Make sure the paper is saturated. Now pour water onto the surface. Let me know how many particles break loose. We'll compare notes if you like... /// My objection to TP - very poor efficiency, migrates particles, migrates fibers \//// You either believe the folks who say that depth filters have saved their fine surface filters from blocking, or you don't. If you do believe that they are reporting honestly, then I imagine you would say that at the operational level, that's the kind of efficiency they prefer? The home test may (or may not) demonstrate that an oil-soaked paper tissue does not migrate particles or fibers. I expect you will let us know if this is misconceived... DO NOT depend on filters to remove the crud in your system. //// Or in the version I prefer, referring only to the surface filters that you use and prefer: DO NOT depend on fine surface filters to remove crud in your system - they will certainly block: fast. Respectfully, Brian Whatcott |
Fuel transfer/polishing pump
Nope.... I suggest a test for you
Take 25-50 grams of the finest dust/crud you can find. Dump it in upstream of a TP filter and see what happens ..... it will immediately plug - or will hardly capture anything. Change to a high surface area pleated filter dump in 25-50 grams of crud, another 25-50 grams of crud, another 25-50 grams, then another 25-50 grams, then another .... then it will plug. Take out the filter, examine .... you will find a small layer of crud on the surface. That layer is called a "filter cake". That layer of debris because the velocity throuth the 'cake' is so much smaller (than the velocity through a TP etc. roll that it does in fact flow and until the cake reaches a 'terminal' differential pressure will be the principal means of particle captu dirt filtering out other dirt. This cannot happen in a depth filter....because there is *no room for the 'cake' to form* (inside the filter). For a true depth filter, you add a filter aid (Diotomaceous earth, perlite, etc.) on a continual basis so that the deposition is controlled, the debris is contained in the cake of DE + crud. The surface of the depth filter holds the cake. If the particles get inside the depth filter it PLUGS. You can design a 'profiled' depth filter that has a graded pore density.... bigger pores on the upstream side, smaller pores on the downstream side ....and that costs about 20 times the price of a toilet paper roll ..... and also is a resin bonded cellulose matrix. Resin bonded so that the cellulose matrix desnt collapse upon itself during increasing differential pressure, doesnt fall apart if it gets wet with water, etc. In article , Brian Whatcott wrote: On Fri, 05 Dec 2003 20:02:22 GMT, Rich Hampel wrote: Please appreciate that I dont want to appear to be an arrogant know-it-all after being in on and around critical filtration/separation most of my working life ... Sounds good to me... /// Whats wrong with TP, etc. is that the material used to filter is not bonded, can digest (make more particles) in the presence of water --- thus to do the exact opposite of what you are trying to do. Perhaps a test at home would be helpful. Take a kitchen collender, A seive or funnel would also work well. Place a sheet of kitchen roll in the aperture, pleated once to fit. Spray the surface with Pam, olive oil, or soybean oil or any other oil Momma has on hand. Make sure the paper is saturated. Now pour water onto the surface. Let me know how many particles break loose. We'll compare notes if you like... /// My objection to TP - very poor efficiency, migrates particles, migrates fibers \//// You either believe the folks who say that depth filters have saved their fine surface filters from blocking, or you don't. If you do believe that they are reporting honestly, then I imagine you would say that at the operational level, that's the kind of efficiency they prefer? The home test may (or may not) demonstrate that an oil-soaked paper tissue does not migrate particles or fibers. I expect you will let us know if this is misconceived... DO NOT depend on filters to remove the crud in your system. //// Or in the version I prefer, referring only to the surface filters that you use and prefer: DO NOT depend on fine surface filters to remove crud in your system - they will certainly block: fast. Respectfully, Brian Whatcott |
Fuel transfer/polishing pump
On Sun, 07 Dec 2003 06:24:24 GMT, Rich Hampel
wrote: Nope.... I suggest a test for you Take 25-50 grams of the finest dust/crud you can find. Dump it in upstream of a TP filter and see what happens ..... it will immediately plug - or will hardly capture anything. I'm just wondering if you've actually tried this test or if it's just based on your theory of the filters. Steve |
Fuel transfer/polishing pump
On Sun, 07 Dec 2003 06:24:24 GMT, Rich Hampel
wrote: Nope.... I suggest a test for you Take 25-50 grams of the finest dust/crud you can find. Dump it in upstream of a TP filter and see what happens ..... it will immediately plug - or will hardly capture anything. I'm just wondering if you've actually tried this test or if it's just based on your theory of the filters. Steve |
Fuel transfer/polishing pump
Doug,
I have used Permatex as a gasket replacement on a gasoline tank. Should work w/ diesel as well. Garland "Doug Dotson" wrote in message ... I won't be able to tell for sure until I open one up. Just looking at them from the outside it appears they are bedded in something black. The outside surface of the tanks are not smooth. If the inside is not smooth as well that would explain why they were bedded rather than gasketted. I think what I may do is have some inspection ports fabricated that can be opened more easily. Doug s/v Callista "LaBomba182" wrote in message ... Subject: Fuel transfer/polishing pump From: "Doug Dotson" Have any idea what might have been used to bed the inspection ports? The ones I have dealt with have had gaskets on them. If yours don't I would look into making some and/or using a fuel resistant sealant. http://www.watkins-associates.com/index.html Capt. Bill |
Fuel transfer/polishing pump
Doug,
I have used Permatex as a gasket replacement on a gasoline tank. Should work w/ diesel as well. Garland "Doug Dotson" wrote in message ... I won't be able to tell for sure until I open one up. Just looking at them from the outside it appears they are bedded in something black. The outside surface of the tanks are not smooth. If the inside is not smooth as well that would explain why they were bedded rather than gasketted. I think what I may do is have some inspection ports fabricated that can be opened more easily. Doug s/v Callista "LaBomba182" wrote in message ... Subject: Fuel transfer/polishing pump From: "Doug Dotson" Have any idea what might have been used to bed the inspection ports? The ones I have dealt with have had gaskets on them. If yours don't I would look into making some and/or using a fuel resistant sealant. http://www.watkins-associates.com/index.html Capt. Bill |
Fuel transfer/polishing pump
On Sun, 07 Dec 2003 06:24:24 GMT, Rich Hampel
wrote: Nope.... I suggest a test for you Take 25-50 grams of the finest dust/crud you can find. Dump it in upstream of a TP filter and see what happens ..... it will immediately plug - or will hardly capture anything. OK; as far as I can tell, particulate fines *will* pass a depth filter on the first pass. This makes your proposition completely true for one clause of the either/or proposition. Change to a high surface area pleated filter dump in 25-50 grams of crud, another 25-50 grams of crud, another 25-50 grams, then another 25-50 grams, then another .... then it will plug. OK: as far as I can tell, particulate fines will mostly pass a surface filter rated for considerably larger particles, and block, for a filter rated at considerably smaller particles. In the intermediate range, as is well known, the retained particulate film provides increasing resistance, and retention of decreasing particle sizes. Take out the filter, examine .... you will find a small layer of crud on the surface. That layer is called a "filter cake". That layer of debris because the velocity throuth the 'cake' is so much smaller (than the velocity through a TP etc. roll This was the only piece that left me uncomfortable. Supposing that surface filters use lower velocity flow than depth filters in the fuel polishing role is presuming a design choice that "don't necessarily happen." Filter cakes are an artifact of surface filters. ....that it does in fact flow and until the cake reaches a 'terminal' differential pressure will be the principal means of particle captu dirt filtering out other dirt. This cannot happen in a depth filter....because there is *no room for the 'cake' to form* (inside the filter). For a true depth filter, you add a filter aid (Diotomaceous earth, perlite, etc.) on a continual basis so that the deposition is controlled, the debris is contained in the cake of DE + crud. I am pleased that you are now referring to industrial uses of depth filters: - like the one that brings you your tap-water, for instance, or the depth filter that brings you your room-air. But pre-loading a filter is not the fuel-polishing approach, so I don't find it specially relevant, The surface of the depth filter holds the cake. If the particles get inside the depth filter it PLUGS. You can design a 'profiled' depth filter that has a graded pore density.... bigger pores on the upstream side, smaller pores on the downstream side ....and that costs about 20 times the price of a toilet paper roll ..... and also is a resin bonded cellulose matrix. Resin bonded so that the cellulose matrix desnt collapse upon itself during increasing differential pressure, doesnt fall apart if it gets wet with water, etc. You again mention non resin cellulose filters falling apart when wet. The home test I mentioned recently (I thought) would convince you that these filter materials *don't get wet* in the intended application? Brian W In article , Brian Whatcott wrote: On Fri, 05 Dec 2003 20:02:22 GMT, Rich Hampel wrote: Please appreciate that I dont want to appear to be an arrogant know-it-all after being in on and around critical filtration/separation most of my working life ... Sounds good to me... /// Whats wrong with TP, etc. is that the material used to filter is not bonded, can digest (make more particles) in the presence of water --- thus to do the exact opposite of what you are trying to do. Perhaps a test at home would be helpful. Take a kitchen collender, A seive or funnel would also work well. Place a sheet of kitchen roll in the aperture, pleated once to fit. Spray the surface with Pam, olive oil, or soybean oil or any other oil Momma has on hand. Make sure the paper is saturated. Now pour water onto the surface. Let me know how many particles break loose. We'll compare notes if you like... /// My objection to TP - very poor efficiency, migrates particles, migrates fibers \//// You either believe the folks who say that depth filters have saved their fine surface filters from blocking, or you don't. If you do believe that they are reporting honestly, then I imagine you would say that at the operational level, that's the kind of efficiency they prefer? The home test may (or may not) demonstrate that an oil-soaked paper tissue does not migrate particles or fibers. I expect you will let us know if this is misconceived... DO NOT depend on filters to remove the crud in your system. //// Or in the version I prefer, referring only to the surface filters that you use and prefer: DO NOT depend on fine surface filters to remove crud in your system - they will certainly block: fast. Respectfully, Brian Whatcott |
Fuel transfer/polishing pump
On Sun, 07 Dec 2003 06:24:24 GMT, Rich Hampel
wrote: Nope.... I suggest a test for you Take 25-50 grams of the finest dust/crud you can find. Dump it in upstream of a TP filter and see what happens ..... it will immediately plug - or will hardly capture anything. OK; as far as I can tell, particulate fines *will* pass a depth filter on the first pass. This makes your proposition completely true for one clause of the either/or proposition. Change to a high surface area pleated filter dump in 25-50 grams of crud, another 25-50 grams of crud, another 25-50 grams, then another 25-50 grams, then another .... then it will plug. OK: as far as I can tell, particulate fines will mostly pass a surface filter rated for considerably larger particles, and block, for a filter rated at considerably smaller particles. In the intermediate range, as is well known, the retained particulate film provides increasing resistance, and retention of decreasing particle sizes. Take out the filter, examine .... you will find a small layer of crud on the surface. That layer is called a "filter cake". That layer of debris because the velocity throuth the 'cake' is so much smaller (than the velocity through a TP etc. roll This was the only piece that left me uncomfortable. Supposing that surface filters use lower velocity flow than depth filters in the fuel polishing role is presuming a design choice that "don't necessarily happen." Filter cakes are an artifact of surface filters. ....that it does in fact flow and until the cake reaches a 'terminal' differential pressure will be the principal means of particle captu dirt filtering out other dirt. This cannot happen in a depth filter....because there is *no room for the 'cake' to form* (inside the filter). For a true depth filter, you add a filter aid (Diotomaceous earth, perlite, etc.) on a continual basis so that the deposition is controlled, the debris is contained in the cake of DE + crud. I am pleased that you are now referring to industrial uses of depth filters: - like the one that brings you your tap-water, for instance, or the depth filter that brings you your room-air. But pre-loading a filter is not the fuel-polishing approach, so I don't find it specially relevant, The surface of the depth filter holds the cake. If the particles get inside the depth filter it PLUGS. You can design a 'profiled' depth filter that has a graded pore density.... bigger pores on the upstream side, smaller pores on the downstream side ....and that costs about 20 times the price of a toilet paper roll ..... and also is a resin bonded cellulose matrix. Resin bonded so that the cellulose matrix desnt collapse upon itself during increasing differential pressure, doesnt fall apart if it gets wet with water, etc. You again mention non resin cellulose filters falling apart when wet. The home test I mentioned recently (I thought) would convince you that these filter materials *don't get wet* in the intended application? Brian W In article , Brian Whatcott wrote: On Fri, 05 Dec 2003 20:02:22 GMT, Rich Hampel wrote: Please appreciate that I dont want to appear to be an arrogant know-it-all after being in on and around critical filtration/separation most of my working life ... Sounds good to me... /// Whats wrong with TP, etc. is that the material used to filter is not bonded, can digest (make more particles) in the presence of water --- thus to do the exact opposite of what you are trying to do. Perhaps a test at home would be helpful. Take a kitchen collender, A seive or funnel would also work well. Place a sheet of kitchen roll in the aperture, pleated once to fit. Spray the surface with Pam, olive oil, or soybean oil or any other oil Momma has on hand. Make sure the paper is saturated. Now pour water onto the surface. Let me know how many particles break loose. We'll compare notes if you like... /// My objection to TP - very poor efficiency, migrates particles, migrates fibers \//// You either believe the folks who say that depth filters have saved their fine surface filters from blocking, or you don't. If you do believe that they are reporting honestly, then I imagine you would say that at the operational level, that's the kind of efficiency they prefer? The home test may (or may not) demonstrate that an oil-soaked paper tissue does not migrate particles or fibers. I expect you will let us know if this is misconceived... DO NOT depend on filters to remove the crud in your system. //// Or in the version I prefer, referring only to the surface filters that you use and prefer: DO NOT depend on fine surface filters to remove crud in your system - they will certainly block: fast. Respectfully, Brian Whatcott |
Fuel transfer/polishing pump
We're starting to flog a dead horse here .... so my very last comment
on all this is: .... take a toilet paper roll, get a container, immerse it in any oil that you want and let it soak, then add 1" of water to settle at the bottom of the container with the TP .... to the bottom of whatever you contain the toilet paper, let sit a week or more, remove and examine that the TP has fallen apart where the water has come in contact with the TP. Now consider that the TP in poorly designed boat system is held in place by a knife edge seal biteing into the end of the TP roll........ What happens later on when there is differential pressure across 'mush' (papier mache) being held by a knife edge seal and has a differential pressure across it. Water in fuel oil is common, as an emulsion from the refinery (errors in handling, etc.) and as the product of condensation on the tank farm walls with water entering the tankage through the tank vent, etc. I've herein posted what is the normal industry methods, 'state-of-the-art' ..... and what is 'snake oil'. ......and thats the final comment from me. You again mention non resin cellulose filters falling apart when wet. The home test I mentioned recently (I thought) would convince you that these filter materials *don't get wet* in the intended application? Ever hear of gravity settling and equlibrium displacement ? Dont consder to ever get a job as a lab tech.... you wont make it. Brian W |
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