Chemical Injection Quills

[jartgo]

I'm looking for operational experience on the best chemical injection quills. Obviously a subjective question, but I'm hoping you all might suggest the most appropriate product.

I'm working at a small water treatment facility that injects the following:
1) Caustic
2) Phosphate
3) Flouride
4) Chlorine

The plant pumps about 250 gpm to the system at appx. 75 psi, and the injection quills will be inserted into 3/4" threadolets welded to a 6" SS spool piece. I prefer to have retractable quills with integral shutoff. Do you all have a preferred brand, material of construction, etc. from which I could develop a specification?

I've left this sort of detail vague in past projects and ended up with something I didn't like, and was not very operator friendly. Thanks in advance.

 

[Chance17]

The quill should end pointing upstream of bulk flow.
Any other configuration may result in "streamline" of the injection and require many downstream diameters for good mixing.
For critical applications the quill should be pointing toward and within 3-4 inch of the actual discharge impeller.
I have good experiences using the critical design when adding catalyst for a polymerization reaction.

 

[semo]

Saf-T-Flo manufactures quill assemblies of various sizes and materials. I've had good luck with their product and mainly used a pvc or cpvc tube (depending on the chemical). Always double check the chemical compatibility.

Most of what I have used has been a saddle type installation with the removable quill. That allows for installation at various locations in the field. And relocations if necessary for compatibility with other chemicals being injected.

Make sure to get some extra quills for the chlorine and caustic as depending on the water chemistry, they can to build up on the end of the tube and plug them. With extra quills, this can be remedied by removing and replacing the quill and soaking the plugged quill in an acid or base solution to dissolve the crystalline plug.