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monkey spanners
07-10-2007, 05:32 PM
Hi All,

I have a customer (cheese maker) who is heating 500L of milk to 63C with electric heaters in a water jacket of the processing tank. He then cools it to 30C by running mains water through the water jacket to waste. He is doing four batches a week at the moment but this is set to double in the future.
He is a bit vague about what he wants but i think he is looking at the feasability of :

A. Using a heatpump to cool the milk quicker than at present and heat or preheat his wash water to save wasting mains water.

Or

B. To speed up the cooling process without making use of the heat.

Any ideas?

Cheers Jon

nike123
07-10-2007, 06:11 PM
To me, it looks like you need some heat recovery plant. Maybe some plate heat exchangers, set of circular pumps, 3way valves and heat insulated tanks (heat and cold banks) could do the most of the job without use of heat pump. ;)

750 Valve
15-10-2007, 03:20 PM
Hi All,

He is a bit vague about what he wants but i think he is looking at the feasability of :

A. Using a heatpump to cool the milk quicker than at present and heat or preheat his wash water to save wasting mains water.

Or

B. To speed up the cooling process without making use of the heat.

Any ideas?

Cheers Jon

Correct me if I'm wrong but he wants to waste energy to save water. As they are both necessities in modern life and both cost for their use I see this as a no win situation. But, free energy can be had from a thermal ground loop but you still have to pay to pump it and thats about it. He may be better looking into thermal storage if his loads increase enough, an ice tank for rapid chill and hot water reclaim system off its refrig system condenser to warm the water but with his current load isn't worth it

get the gauges
15-10-2007, 05:40 PM
Is this a job for bulk milk tank the dx type with a heat pump attached , i'm not an expert on 'em. Or anything for that matter. This is a good contact for food grade heatexchangers and heat pump stuff. Swep InternationalSwep InternationalStourbridge
DY7 6YG, UK

01384 878031


I was going to do a job cooling milk down and these lot sell refrigerant to product food grade Ht Ex's

monkey spanners
15-10-2007, 07:21 PM
Thanks for the replies, its a bit of a no brainer, but i have to be seen to be doing something.
I've told him that if he started with a new setup it could be designed to be as efficient as possible but keeping all the old crappy stuff hes got running is bad enough.
I've also suggested an old 300g milk tank for iced water, but when i said it would cost a couple of grand to buy and install he went a bit quite.

Cheers Jon

trang
16-10-2007, 02:38 AM
Hi. thank you all of you

The MG Pony
18-10-2007, 05:57 PM
Thanks for the replies, its a bit of a no brainer, but i have to be seen to be doing something.
I've told him that if he started with a new setup it could be designed to be as efficient as possible but keeping all the old crappy stuff hes got running is bad enough.
I've also suggested an old 300g milk tank for iced water, but when i said it would cost a couple of grand to buy and install he went a bit quite.

Cheers Jon

I find in cases like that it helps to remind him of long term benifits such as reduced running costs reduced maintanance needs, better production quality and speed. things like that that pay it back in more ways then just cash!