Using two glycol storage tanks in a cooling circuit ? Please help

[mad fridgie]

Best give you a non real world example

Imagine;
All mixing in the save tank and same flow to process and chiller
you want 5C going to the process
10C is coming back from the process
Therefore
5C must be entering the chiller
0C must be leaving the chiller.
The chiller saturated suction temp (SST) would be -5C.

Let then presume we a have twin tanks .
The 10C from the process effectively goes into the chiller. and 5C leaving the chiller and going to the process.
All things being equal, the new SST would 0C
the chiller .
the increased SST would give approx 20% more net refrigeration, for very little increase in power use.
So your COP could go from say 3.5 upto 4. So around a 6% saving in power.
Of course this will change depending upon refrigerant, compressor type and working conditions (pressures, flows, temps)

[shooter]

boost you are giving him a good thinking.

I would go for all glycol coming back direct to the chillers, this will improve the exchange in the chiller as boost is telling you.
Use another chiller to keep the buffer on correct temp.
If the chillers can not keep up, then use the buffer tanks.
In the night use two chillers to cool down the buffer for the day time.