Minimum fill for a small bulk tank?

kowtow

We're looking for a small second-hand bulk tank (plenty around at the moment) for the parlour - and I'm concerned not about how much milk I can get into it but how little!

Firstly, our numbers will be small by any normal standards - 12-18 milkers next year and likely no more than 24 or 36 in future years.

And secondly, we will be primarily milking for cheese, mostly making within 24 hours of milking, with only surplus milk going to the co-op, presumably on a 3 day collection to match my neighbours.

I have been told in the past that there is a minimum level of milk required for the agitators to function, and in any case there must be a minimum level required for optimum cooling...

I'm looking at 400 gallon tanks at the moment - but will this be too big altogether? Is there one design (round, square, oval) which is better than another in these circumstances?

I do have an old Etscheid immersion cooler but although it hums along I think the gas is long gone - otherwise I'd go looking for one of those neat little round tanks on wheels to match it. If I could find one with functioning cooling I'd be laughing...

Nekarsulm

With direct expansion tank's, the problem with only having a "sup" of milk in the bottom is twofold. Firstly, if the milk is not up to the agitator, it wont cool evenly, and even more troublesome, the milk will not reach up to wherever the temp. sensors are inside the skin of the tank. So the tank will keep cooling and you will get a frozen solid lump or milk in the bottom. It could take a day or two to thaw... Buy the smallest tank you can get away with.
A 2000 litre tank will be too big, if you are using much milk daily for your cheese making. It would be too big for 24 milkers even on 3rd day collection and no chees making.

kowtow

Nekarsulm wrote: »

With direct expansion tank's, the problem with only having a "sup" of milk in the bottom is twofold. Firstly, if the milk is not up to the agitator, it wont cool evenly, and even more troublesome, the milk will not reach up to wherever the temp. sensors are inside the skin of the tank. So the tank will keep cooling and you will get a frozen solid lump or milk in the bottom. It could take a day or two to thaw... Buy the smallest tank you can get away with.
A 2000 litre tank will be too big, if you are using much milk daily for your cheese making. It would be too big for 24 milkers even on 3rd day collection and no chees making.

That's basically what I was worried about.

What about the small circular Etscheid type tank? I have an immersion agitator and cooler for one, but although it buzzes along and agitates (and the fan runs) I think it is doing more warming than cooling... presumably these work in smaller tanks, and with small quantities of milk - when I bought it it had last been used in a milk churn.

I suppose it would be easy enough to find one of the small round tanks, but whether it is possible to get the gas changed in the immersion cooler I don't know... either that or try and find one with a working cooler.

I'm not well up on tank cooling... is an ice bank a better solution than direct expansion? Or does the same apply?

C0N0R

Can't offer much help on the cooling side of things but we used to use a vice grips to attach an ice cream lid to the agitator when we had small amount of milk. Turn on refrigeration until it had reached desired temps then turn off.