airlifting model for wastewater sludge

In depth subjects relating to Airlift.
Post Reply
Posts: 1
Joined: 10 Apr 2020, 16:46

airlifting model for wastewater sludge

Post by Rita »

Hello everyone,

I am trying to build an airlift model for sewage sludge in a septic tank. My goal is to use the same air pump for the airlifting and for water aeration in another tank. I know this is not the conventional application here but I would appreciate your insight.

The water depth is 1.2 m and I want to lift the sludge to 1.8 m (0.5 m lift) to a barrel. A single pump should be enough for I don't need a big pump for aeration. The aeration is continual and the sludge airlifting would occur once every 6 months or even a year so I'm trying to not purchase a big sludge pump and thinking of trying airlifting. I have already tried it with a compressor and turns out I need a pressure of 1.7 bar but the compressor is not very practical and efficient.

I have a 25 W aquarium pump with a pressure of 0.025 MPa and 30L/min output and I am thinking of using a 100 mm pipe for the pressure chamber and 110 mm pipe for the airlift. I think that I am going to need a bigger pump but do you think that if I use the same pump with smaller pipes it would be more efficient? and if not what do you recommend for pump and pipe size?
User avatar
Posts: 193
Joined: 11 Dec 2015, 00:12
Location: The Netherlands

Re: airlifting model for wastewater sludge

Post by Pssymon »

Hi Rita,

Apologies for missing this thread.
I understand what you are trying to do. However 50cm is still a massive discharge head. A 25W air pump will never be able to provide enough lift to get there. A 110mm rising tube will also be much too large. To give you a rough estimate (I have not done tests like this as we work without discharge head), I would go down to at least 50mm and try at least a very good 100W pump. Even then, I think you will have a difficult time overcoming the discharge head.

For reference, please take a look at this video:
Post Reply