Help: air ejector driven deaerator

[Kencurtis]

I have a Weir Ltd. N0.3 Deaerator with devapouriser of 1947 vintage. The unit is fitted a steam to air ejector which was driven HP steam. I have since fitted shell boilers which operate at 10 barg. Consequently, it is doubtful that the air ejector will operate with this lower steam supply pressure.

Can anyone out there advise if they have had similar issues and what remedies and/or solutions were adopted. We are currently considering a vauum pump to provide the role of the air ejector.

 

[quark]

What vacuum level you require? In the past I used steam jet ejectors to get 5mm Hg abs. with 10 barg pressure. Check the capacity of ejector and also check for proper condensation of steam.

This link will be helpful to you.

http://www.graham-mfg.com/ejlibrary.html

Regards,

 

[rmw]

If your motive steam to the jet is now at a lower pressure than the jet was designed for, then it has higher specific volume, and less of it can pass through the nozzle of the jet, degrading the performance of the jet, if not downright impeding it.

Assuming you would not be asking if you could get a new deaerator, you should get your jet renozzled for the current motive steam conditions, or you may have to replace your jet altogether.

rmw

 

[sailoday28]

This is new to me. Help educate me.
What is the line up? Where is the ejector pulling from and discharging to?

 

[quark]

sailoday28,

Have you received my mail and attachement about compression basics I referred in other thread?

 

[sailoday28]

quark (Mechanical)I don't know if the above website will help. I'm a little lost on what is up downstream of the air ejector/ DA tank. ie Is motive steam coming from DA or is air ejector taking suction from DA, etc.?

 

[jproj]

sailoday28:

Motive steam enters the ejector from a high pressure source. A steam / air mixture from the deaerator vent line is "sucked" into the ejector by the motive steam. The steam and air mixture is then ejected to atmosphere (eventually).

jproj