Tube in tube pre-cooling

Is it possible to lower energy costs keeping high quality of the milk produced?

There is a very simple way to do it.

Depending on the quantity of the milking herd energy costs can be lowered both by the milk pre-cooling and refrigeration factor heat recovery. Margo offers two devices that can manage this task: tube in tube pre-cooler and a helical coil heat exchanger. Margo’s equipment for energy saving is produced from stainless steel only. Application of these products helps obtain warm water in the result of milk cooling. Warm milk both directly (pre-cooler) and indirectly (heat exchanger) raises the temperature of the water and thus lowers electricity consumption of the refrigeration process.

Margo provides heat exchangers for small cattle farms with the production starting from 500 litres of milk per day. Medium and large agricultural businesses are especially offered tube in tube pre-coolers.

Research results published by the Institute of Technology and Life Sciences (supervised by the Ministery of Agriculture) proved that „implementation of the milk pre-cooling system gives rise to electricity consumption savings of approximately 50%”.


Table: Research results on electricity consumption savings in selected cattle farms according to the Institute of Technology and Life Sciences.

Farmhouse Quantity of cows in the herd Milk harvest Electricity consumption per milking Financial expenditure reduction
Daily [dm³] Per annum [dm³] Conventional method [kWh/Dz] Including heat recovery kWh
Daily Per annum
1 69 1300 474500 14,00 7,5 2737,50 842,40
2 140 2800 1022000 24,77 12,39 4522,35 1628,05
3 201 4100 1496500 70,26 35,13 12822,45 4616,08
4 400 7956 2903940 65,06 32,53 11873,45 4274,44
5 250 5342 1949830 52,41 26,21 9566,65 3443,99
6 700 13041 4759965 127,93 63,97 23349,05 8405,66
7 80 1800 657000 39,97 19,99 7296,35 2626,69
8 190 4130 1507450 70,11 35,06 12796,90 4606,88
9 300 5753 2099845 56,44 28,22 10300,30 3708,11
10 100 2054 749710 20,15 10,08 3679,20 1324,51

References: Myczko Andrzej, Szulc Robert: „Milk pre-cooling vs reduction of a carbon dioxide emission.

How does the pre-cooler work?

Tube in tube pre-cooler is assembled between cooling tank and the milking machine. This simple solution consists of stainless steel tube in tube. Milk harvested from the cow is transported via inner tube and during this process gives away its warmth to the cold water flowing in the outer tube. Cold water inlet is situated on the opposite site to the warm milk inlet. Warm water obtained this way can be utilised for cows watering (warm water is preferred by the cows which results in higher milk yield), installation cleaning, heating, etc. Extra advantage is the pre-cooled milk is delivered into cooling tank.

The yield of milk harvested determines the size and complexity of the tube in tube pre-cooler. Unit already assembled is maintanance free. It is cleaned automatically by the milking machine washer. Long lasting durability is quaranteed by the stainless steel structure. It is recommended to clean the whole equipment once to twice a year. Descaling treatment is unnecessary for limescale precepitates in water exceeding 60 C degrees and the water heated in the tube in tube device does not reach mentioned temperature.

Advantages of tube in tube pre-cooler

  • shorter milk cooling time – energy friendly
  • higher milk quality – less bateria
  • warm water fo free – saves money
  • larger milk yield
  • reduced operating time of a cooling unit – increased service life.

Device characteristics:

  • water to milk ratio 2:1
  • water and milk circulation regulated by the valves
  • initial milk temperature 32 C degrees
  • milk temperature after pre-cooling 16 C degrees
  • initial water temperature 7 C degrees
  • final water temperature 16 C degrees.

Tube in tube pre-cooler is manufactured in two classes.

Output according to the circulation of milk in litres per one hour

Milk tube diameter [mm] Water tube diameter [mm] Output
in litres per hour
Length [mb]
32 48 1000 12
32 48 2000 24
32 48 3000 36
32 48 4000 48
32 63 6000 72
32 63 8000 96