Fat Tank Pumps Won't Pump

Viscosity of the fat could be a problem. The head pressure in the tank could be aiding in forcing the fat thru the strainers to the pump inlet. At some level you no longer have this aiding head pressure. The stainer may be restricting the flow due to the fats viscosity. Increase the surface area of the strainer may help.

thank you

The original depth adds Head Pressure to the Pmps Suction and forces the fat to flow. As product depth decreases its Head Pressure decreases and finally stps flowing since the Pump Suction is not enough to move the Viscous material. A Low Pressure Gauge that reads, say 0-15 PSI, at the bottom of the tank would show the Head Pressure as it falls.

Also, if the Tank can't breath there could be a Vacuum that is stopping flow.

One possibile fix would be to add some extra pressure to the tank if it was designed to hold pressure. Even a high flow Blower might work. That would force the fat to flow as it did when it had higher Head Presuure from more depth.

Goshhh! All sounds good. But make sure the pump intake is plenty and heat up few degrees the product as needs it in order to make flow more liquified tour the pump my friend. All else seing to be fine so far here.

Crank that Puppy Up,

MC

thank you//tb

Good answer. It's too thick to flow into the inlet. If the pump stops, the fat flows down to cover the inlet. Then, everything works till the pump sucks the fat into the inlet, with air. Google: viscosity a d thixotropy.

What type of pumps are you using?

Why not use a secondary feed of the first pumped volume to thin out the last portion of the tank. Siphon off some of the first pumped back to the tank and mix it with a drill mixer to thin out the mess. You got another possible way. Tap a hole into the bottom of the tank where the thick solution can be drained out after removing the best portion from the top of the tank using the pump. Doing this your not making extra work for yourself having to allow the entire solution to settle again once it was siphoned out to remix with the first volume removed. Hole tapping should be your choice in this problem. You can also consider closure of the tank top and add pressure from the top and that should allow the bottom to flow out faster tilting the tank so to get all of it out. If the thick solution has somewhat dried into a cake it cannot pump or be blown out and you will have to heat a solution to melt down the dried portion to get it to flow out of the tank. If your handling a sealed tank you cannot dip that goop out and have no choice that to use some of the original solution heated up to melt that goop cake and then pump out the goop as normal operation.

Could be if using centrifical pump, the pump heating by fat friction may cause enough vapour from fat to cause vapour lock. This may not become appearant untill fat head (ie volume in tank) pressure is reduced to point it cannot overcome vapour lock. Suggest drill and tap small hole in pump and fit a pressure gauge. If gauge pressure drops at low fat level then replace gauge with small air valve. This will release any vapour lock.

Cheers

Peter

Thank you//tb

If all else fails, try to pressurize the tank a bit that is if you can.

Wangito

I used a few of these on an outdoor fat/sludge pumping project a few years ago they'll pump almost anything. They'll run you approximately $7000.00 US +/- with freight.

Seepex Progressive cavity pump, Model: BN17-6L/A1-C1-C6-FO-GA, with a 5 HP, 1725 RPM, 230/460 V, 3PH, 60 HZ, TETC gear motor with Class F insulation.

An indoor application for edible fat production requires a different stainless steel "wash-down" rated pump.

A decient sales rep can cover you up with options. The hard part is getting the capital.$$

Animal fat is like ice it, floats as it solidifies, so maybe you just need to raise the temperature a few degrees.

First be careful about increasing pressure to the tank unless it is rated for pressure. Second I have pumped alot of fat at feed mills and we always heat the product well above your 80*f. As a test drop some hose that will handle very hot water or low pressure steam down into the tank all the way to the cone. Run some heat through the hose and watch the fat flow. I also have used diaphragm pumps in this application.

Let us know what happens.

Mike

i am going to drain with diaphragm pump clean and check for sludge build up. thanks for input.//tb

The data should also contain following :

1) Inlet pipe size to the pump

2) Type of pump and its operating speed and the rated capacity ( flow rate)

3) if a compound gauge is available at the pump suction.Reading of the gauge during start up and when you start experiencing the problem with pumping.Pump manufacturers use a term NPSHa and NPSHr to denote the Net Positive Suction Head -available and required respectively.If NPSHa>NPSHr well and good otherwise you may expect a drastic rerduction in flow rate.Looking from what you have said,this is what your problem is in a nutshell.

Higher temperature will bring down the viscosity and therefore the suction losses- this costs extra and sometimes the product can't be heated beyond a certain temperature.The other alternative is to lower the pump location w.r.t. the tank outlet.

If you are resourceful , you can install a VFD.Use the pump at a slight higher speed to begin with and as the static head on the suction becomes lesser during pumping - gradually lower the speed to match that of the influx of liquid.Pump makes a peculiar starving (cavitation) noise and this is good indication to start lowering speed of the pump till the noise ceases.In short,the major problem always has been -how to get the liquid into the pump ratehr than getting it out of pump.

Analyse and you will solve the problem yourself!

Good luck

Chuck Cowlagi