Chiller Water Loop Contamination

pradeepbarola

Hi

Its an existing industrial problem. There is a chiller system and two separate Water Circulation loops are there for water flow.

First: Piping of the Chiller ( Made of Copper), then Mild Steel Piping upto the storage vessel and the to plate heat exchanger (PHE).

Second:

Water Circulation loop ( made of SS 316 L) in the plant which passes through PHE for heat exchange.

Check the attached images

The water in the above two loops two not come in direct contact with each other.

Both the loops have water circulating through them. Now I want to remove the PHE system and send the water directly from chiller storage to plant. The issues of using it are.

1. Contamination from Mild Steel and Copper pipe will spread in the whole plant.

Now I want to know:

Q1. Will the contamination will be really significant if I bypass the PHE. FYI the plant chilled water is used in the Vessel Jacket for Heat Exchange only. So its the issue of life of Jacket and will there be a considerable impact on it.

Q2. Are the any filters available to avoid spreading of Contaminates beyond a certain point.

Q3. Will replacing the Mild Steel Pipe by SS solve the issue. And is so will copper be a remaining issue.

Looking forward for an early reply

Thanks in Advance.

Attached Thumbnails

   

Danger

Greetings.
I'm pretty sure that I can't help you at all, but I would like to clarify something. Are you referring to metallic contamination from the pipes themselves, or contaminants that happen to be in the pipes?

Travis_King

Does your chiller only use water? There's no glycol mixture or similar?
What kind of chiller is it: Air-cooled, water-cooled, evaporative?
Depending on your answer to that question, where does make up water to the chiller come from (if applicable)?
Has the water in the process loop been treated at all (softened/filtered/etc)?

We don't know the age of your system, so who knows what kind of contaminents are in your piping...

Also, you wont see the 7.5-8.5 C from an input temp of 12-14 at the current operating duty. The output temp from the chiller is determined by the input temp of the water. If you put water at 14C in, you'll get water at around 11-12C out, if the system is left as it is.

pradeepbarola

@Danger: I can say particulate matter from the mild steel pipings,
@King: Only water is used, its a Air Cooled chiller system, the system is 4-5 years old
just to clarify 7.5-8.5, 10-11 is the chiller loop inlet and outlet temp. respectively, and 12-14, 10-11 are the inlet and outlet resp. for process loop.

Even if the pipes are having contaminates , the water can be replaced before installing new piping.

Danger

My first assumption was correct—I can't be of assistance to you. Sorry about that. Best wishes for a resolution.

Travis_King

OP, I understood where the temps were being indicated. My point was that the chiller can only cool the water a certain delta-T for whatever flow you've got. Getting rid of the heat exchanger means the chiller inlet temperature is higher (since it's direct from the process) and therefore the outlet temperature will be higher unless you increase the flow, probably, significantly.

As for your concern about contamination...there is no way to get around it if you wish to use the chiller you've got. I don't know your contamination limits, nor an I familiar with what, and how much, contaminents are released from copper tubing and steel pipe, so I can't comment on that. But if they are that worried about it, you have to keep the heat exchanger.

Removing it will:
--Make your process less efficient by driving temperatures up (increasing BTU requirement for chiller)
--Introduce contaminants (even if you buy all stainless piping, you'll still have copper in the chiller. I'm pretty sure no chiller uses SS tubing).

Is the water in the process loop (not the chiller loop) treated?