landfill leachate pumping
landfill leachate pumping
(OP)
I have a pumping station in one of my sewer districts which pumps leachate from a capped landfill. The problem is that after a few months, the pumps and piping in the wet well become clogged with what appears to be iron or clay. The 4" force main is reduced to the size of a quarter after just 6 months. This leads to premature pump failure. Anyone with a similar experience and possible solutions. Thank you.





RE: landfill leachate pumping
Depending on the conditions of the fluid, a filter at the suction might prove useful too.
Might want to mention tto the stake holders that the capping needs to be worked on.
RE: landfill leachate pumping
RE: landfill leachate pumping
Do you have any ability to dilute the leachate in the station? domestic force mains nearby? a groundwater or stormwater source? Anything?
How much leachate per day is going to this station?
Also, are you sure you are getting 2 feet per second velocities in the FM?
I would also suggest keeping in mind that a pigging station or a pressure cleanout might help. This would allow the Utility to either 1) flush the line periodically or 2) send a "pig" through to clear any obstructions.
RE: landfill leachate pumping
RE: landfill leachate pumping
You really need to have the waste stream characterized to see what's in it. Maybe chemical addition would work, but I personally hate to think of adding more maintenance headaches to the situation.
The only other solution I can think of is to tap into the FM just in front of the pigging vault and run some temporary piping back into the station. I suspect that since the friction losses would be greatly reduced you could send some pretty good flows through the station & valve vault piping and get a good scouring velocity. Just make sure your pump motors are not power limited before doing so and that you properly restrain the temporary piping.