Sludge pumps with better valves?

  • dandreatta
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Sludge pumps with better valves?

There seem to be 3 types of sludge pumps out there, the Gulper, the Rammer (also known as Gulper 2.0) and the Beaumont Sludge Pump. All of them seem to have valves that are easily clogged with trash. The photos I've attached are from a day in Malawi, with me operating the Gulper, the clogged Gulper getting fixed, the trash that come out of the Gulper, and a close up of the valves of a clean Gulper. The Gulper worked really well until it clogged.

Various methods have been tried to screen the trash before it hits the valves. It would seem that this may or may not work, and in any case is only a partial solution.



I am starting a project to build a sludge pump with valves that are less likely to clog. What I would like to know is, has anyone tried other types of valves, and how did they work.

I'm looking at two types of possible valves. One is a flexible check valve made of rubber, sometimes called a duckbill valve due to its shape. Commercial valves are very expensive, it may be possible to make a home-made version. The other valve is a single sided flapper valve similar to what is in the bottom of a flush toilet tank. These are cheap, but hard to fit in a small space. Using either type of valve is not an easy task, so there is no promise that this will work. I hope to have something working by the time of FSM5, and to do some field testing while in Africa.

Thanks,

Dale Andreatta, Ph.D., PE
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Dale Andreatta, Ph.D., P.E.
Mechanical Engineer
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  • JKMakowka
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Re: Sludge pumps with better valves?

A slightly larger neoprene tricuspid joker valve (commercial sizes are commonly only 1" or 1 1/2") would probably work well. But I doubt they could be made in a DIY fashion.

For the single sided valves, look for "scupper valves". For hand-pumps a common version is made from a leather flap. But I am not sure those would work well for sludge with solids.

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  • kelldigest
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Re: Sludge pumps with better valves?

Hi Dale,
It is interesting to see that regardless of what country you are in, people keep throwing trash into their septic/sewage systems.

The best advice I could give is a coarse screen before the valve that might stop stuff getting stuck in the valve and make it easier to clean.
Also, as an operational routine, moving the pump frequently may allow trash that is getting pulled towards the pump to move away.
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  • dandreatta
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Re: Sludge pumps with better valves?

Regarding screening the trash, if you put the trash screen at the inlet then the trash just accumulates in the pit and must eventually be dealt with. If you put the trash screen above ground but before the valves, as with the Beaumont Sludge Pump, then you must open the system frequently to take the trash away from the screen. The Beaumont pump has a mechanism for doing this without too much effort, but it still takes some time .

I believe we can and should do better. One could see trash in the pit as an opportunity to provide sanitation service and municipal trash collection at the same time. Everywhere I've been in the developing world the trash accumulates, creating a trash nuisance, until someone sets fire to it, creating a smoke nuisance.

Bucket-based manual methods exist for handling the trash and sludge together. My Sludge Digger and Sludge Dipper designs do this. The Dipper is for thin sludge only and the Digger handles thick or thin sludge. See:

https:\\youtu.be/9za_f-FhVvk

For taking the trash only out of the pit, there is the crabtrap, mostly designed by some students that I worked with a couple years ago:

https:\\youtu.be/GDX3ii07SiA

None of these are as neat and tidy or as fast as a sludge pump or a vacuum truck, hence I believe we need a sludge pump with valves than can handle trash.

Dale Andreatta

Dale Andreatta, Ph.D., P.E.
Mechanical Engineer
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