Sludge main between Plants

[ouphido]

We have a 8" sludge line running approximately 19,000 feet. Would the sludge line be designed like a force main with respect to air release valves? The line will be relatively flet throughout the run. I've never had expreience designing a sludge line for a run like this. Any help would be appreciated.

 

[bimr]

If the pipe route is relatively flat, you probably do not need air release valves.

You need to focus on maintaining flow and keeping a minimum velocity to keep the material suspended. Pipelines like this work best when operating 24/7 instead of starting/stopping.

You should have some type of water flush and provisions for cleaning the pipeline.

 

[stanier]

I would avoid conventional air valves on a line of this nature. The likelihood of air coming out of solution and not being conveyed with the sludge is remote.

Go to a refinery and see how many air valves there are. None

Go to a power station pumping dense fly ash and see how many air valves there are . None. I have been part of a team that designed an 11km ash slurry line that went through undulating country. No air valves were required.

Go to a mine and see how many air valves there are on the tialings lines . None.

Air valves appear to me to be an abberation of the water industry that is not seen in other industries.

The downside of air valves in this service is that they will require exessive maintenance, will probably clog and wont work.