8 replies to this topic

[Lyne]

Hi,

As per shell dep, chemical injection points shall have a non return valve upstream the block valve to avoid utility contamination, in case I have a two diaphragm pumps each dosing pump has it's own check valve and the distance from the injection point is 12m, can I delete the check valve at injection point ? Do you see that it's necessary to have the check valve at injection point, Until now I never saw a chemical injection point without a check valve, and I'm confused.

Thank you

Edited by Lyne, 15 May 2024 - 12:03 AM.

[breizh]

Hi,

Share a sketch to avoid misunderstanding!

Yes, contamination is a risk, and one check valve may not be sufficient 

I've a bad experience where plant water was contaminated with Caustic soda solution, water was used to dilute caustic for washing distillation columns.

Breizh 

[Lyne]

This is my injection point and my chemical injection skid configuration (Injection into a production wellhead downstream the choke valve)

Attached Files

•  CI1.jpg   58.17KB   3 downloads
•  CI.jpg   6.38KB   2 downloads

Edited by Lyne, 15 May 2024 - 02:22 AM.

[breizh]

Hi,
Hazop study should be the answer, acknowledgement or not of back flow and consequences.
Breizh

[fallah]

As per shell dep, chemical injection points shall have a non return valve upstream the block valve to avoid utility contamination, in case I have a two diaphragm pumps each dosing pump has it's own check valve and the distance from the injection point is 12m, can I delete the check valve at injection point ? Do you see that it's necessary to have the check valve at injection point, Until now I never saw a chemical injection point without a check valve, and I'm confused.
 

 

Hi,

 

The check valve should be considered there to prevent back flow of the process fluid into injection line, in the case of pump trip, which can contaminate the injection fluid even till the pump itself. The second concern is non compatibility of the injection line material with the process fluid which can cause injection line damage and weakness.

[Lyne]

As per shell dep, chemical injection points shall have a non return valve upstream the block valve to avoid utility contamination, in case I have a two diaphragm pumps each dosing pump has it's own check valve and the distance from the injection point is 12m, can I delete the check valve at injection point ? Do you see that it's necessary to have the check valve at injection point, Until now I never saw a chemical injection point without a check valve, and I'm confused.

Hi,

The check valve should be considered there to prevent back flow of the process fluid into injection line, in the case of pump trip, which can contaminate the injection fluid even till the pump itself. The second concern is non compatibility of the injection line material with the process fluid which can cause injection line damage and weakness.

This injection line is in stainless steel 316L and the injection point is downstream choke valves (multiphase flow) which includes produced water. If the chlorine content in the produced water is high, will this damage the injection line (for a short period) ?

[fallah]

 

This injection line is in stainless steel 316L and the injection point is downstream choke valves (multiphase flow) which includes produced water. If the chlorine content in the produced water is high, will this damage the injection line (for a short period) ?

 

 

Hi,

 

Yes, the high chlorine content in the produced water can damage the Stainless Steel in the form of pitting corrosion...

[breizh]

Hi,

 

this material could be suitable for your application: Rilsan

https://shop.poggi-s...cts/rilasn-pipe

 

Breizh

[Lyne]

Thank you everyone for your response