Process chiller - Typical operating temperatures?

[desA]

Hi everyone,

I have an application where the client wants to dehumidify a process gas stream, using a cold water flow.

I have two options:
1. Standard chiller circuit : 7'C delivery, 12'C return.
2. Antifreeze/water circuit : temps to be determined.

I have option (1) fairly well covered, it's option (2) where I need a lot more info.

How low a temp in an antifreeze/water circuit is typical in the industry?
Which antifreeze is preferable : ethylene-glycol, or propylene-glycol (less toxic), from a performance point of view?

Are there any particular additional safety features that should be considered for a low-temp chiller, over that of a standard chiller circuit?

Thanks everyone.