Ejector for pump out water
Ejector for pump out water
(OP)
Hi!
I have ethylene pumps installed under ground level in a pit because of NPSH . The pit dimensions are 6x4m and the pit is 4m deep.There is no drainage so all rain finishes on the bottom of it, and you can't walk in a 20cm deep water:)
The problem is :because of explosion zone i can't install any electric pump to pump out the water,so my idea is to install some ejector(i have 5 bar compressed air available to use). Is it possible to pump out water with ejector(5 bar air) from 4m deep pit and if not what would be best solution?
tnx in advance
I have ethylene pumps installed under ground level in a pit because of NPSH . The pit dimensions are 6x4m and the pit is 4m deep.There is no drainage so all rain finishes on the bottom of it, and you can't walk in a 20cm deep water:)
The problem is :because of explosion zone i can't install any electric pump to pump out the water,so my idea is to install some ejector(i have 5 bar compressed air available to use). Is it possible to pump out water with ejector(5 bar air) from 4m deep pit and if not what would be best solution?
tnx in advance





RE: Ejector for pump out water
http://www.wildenpump.com/
RE: Ejector for pump out water
For pumping out water I'd use an eductor with water as the power fluid. It sounds like you could do this one with a garden hose and a plastic water-bed pump. Total cost around $30 (call it 20 Euro's) if you have to buy new hoses. Since it is inside a plant, you'll have to add a bit to comply with safety standards and regulations, your new cost should be under $30,0000 (call it 20k Euro's). The hose and blue plastic water bed pump would actually be safer, but that is not one you are going to be able to sell to the Nanny Society.
David
RE: Ejector for pump out water
yes ,i also thaught about this since we already have wilden pumps on plant,but for this purpose it would be not the best option because it also has moving parts and you need that to be certified for zone ,expensive,complicated,i need simpler solution
zdas04
i didn't understand completely, why waterbed pump if i take eductor? Of other medium available for ejector/eductor power fluid on plant i have 3bar steam,air already mentioned,and water,why i need waterbed pump if i install eductor with water from piping as a power fluid?i want to avoid any electric motors or pumps if it is possible
yes solution with waterbed pump is simple but regulations made it different
tnx for your answers
RE: Ejector for pump out water
David
RE: Ejector for pump out water
RE: Ejector for pump out water
Using 1.5cm pipe or smaller plastic tubing, route it down one pit wall, across the floor, and then up the other side and to a drain. In the section of pipe running along the floor, have a "T" fitting with a short stub of pipe. Put a free-floating check valve on it, oriented so that it allows flow into the pipe. Connect your compressed air to the end of the piping with a valve.
With the air valve closed, water will flow into the pipe along the floor. When you open the air valve, the initial flow out will push the check valve closed, then the water will be forced up and out to the drain. Keep cycling until the water level is all the way down. This won't get all the water though. You could even use a float switch and automate the valve.
If you would like, you can use very small tubing and run it back-and-forth across the pit floor several times in order to capture as much water as possible each cycle. I don't know how small of a floating bean check valve you can get, but 6mm thin-wall plastic tubing would only leave 2mm or so water in the bottom. If you use small tubing, use several check valves to get a higher inflow rate.
In my sketch, I was thinking of a swing check valve, but you probably can't get them is small enough sizes so that they allow in the most water and leave the least depth. The drain must be open to the atmosphere, or you will need a standpipe type vent so that the water can flow into the pipe. If you use a pneumatic valve on the air-control, you can use a 2-way and let that be your vent.
RE: Ejector for pump out water
RE: Ejector for pump out water
RE: Ejector for pump out water
micalbrch,dcasto,kacarrol
it' s not a question ,all those pumps exist in explosion proof version but it's much more expensive solution than some eductor. And that's what i want :cheap but good enough solution .
tr1ntx
interesting idea,tnx for drawing
Finally i see two solutions :
-eductor with water
and second one which is most interesting and simplest solution
-"mamooth pump principle" -you have only two pipes ,one with compressed air and other one for pumping out water out
if anyone has any experience with these pumps, or know where you could find instructions for sizing that system? it would be very helpful to me
i mean how to determine size of pipe for water ,height of tie in of air piping?
my conditions are 3.5 m height of sump and water level in it is max. about 0,5m,air pressure 5 bar