DE3724755A1 - Method for utilising energy during heating of skimmed milk - Google Patents

Abstract

The OKMEV process is particularly suitable for saving cooling water, heating and cooling energy in cheesemaking plants. The cooling power of the raw milk is used for precooling the cream products, with some of the warming-up energy for the vat milk being extracted from the cream at the same time. Furthermore, cooling water is no longer needed for precooling the cream.

Description

The invention relates to a modified method in the Er heating skimmed milk (e.g. kettle milk in cheese factories), whereby the cold energy of the raw milk used to pre-cool the Rahmes is used.

The changed procedure saves a large part of the thermal energy during boiler milk heating. Furthermore, cooling energy becomes a saved in cooling the resulting cream, here the Use of cooling water can be dispensed with completely and additionally Cold energy saved in the deep-freeze department (ice water) becomes.

The procedure currently used in an operating room for heating skim milk and cream requires large amounts of steam to heat the skim milk and reheat it after regenerative heat exchange with the raw milk. Steam is also used to heat the cream. ( Fig. 4)

In addition, ice water is used to freeze the heated cream needed after having previously had large amounts of cooling water cooling of the frame were used.

Newer processes already use a raw milk pre-chiller the frame, whereby the use of cooling water is also omitted. However, these processes require an increased technical level wall (volume and temperature control) and achieve only low Energy savings.

This raw milk partial flow pre-cooling is especially for the constant keeping the separator temperature has been developed and has its Main use in dairy farms where the milk behind the Heating in the coldest possible condition (tem temperatures below 10 ° C).

The process presented here also achieves the cooling water savings with significantly increased additional energy savings in dairies where the skimmed milk contains more than  15 ° C should leave the operating room. (e.g. kettle milk, back acidified milk, special sour milk products) This result is achieved in that the cold raw milk (approx. 6 ° C) before it is pumped into the milk heat exchanger, heats up in the pre-cooler of the frame (up to approx. 15 ° C). Because the entire raw milk flow is conducted in this way, even the largest possible energy exchange take place. Here is particularly too take into account that the energy flow is used twice because on the one hand, the desired preheating of the milk takes place, and on on the other hand, the cooling of the frame quickly and almost completely is possible without auxiliary materials and additional cooling energy expenditure.

In addition to the advantages mentioned above, only one little technical effort required for the new procedure is. When converting existing systems, only the installation of a few meters of piping and switching the Cream precooler.

The laying of the raw milk line must now be done by the pump to the cooling water inlet of the cream apparatus, and the return takes place from the cooling water outlet of the cream apparatus to the heat exchanger inlet of the milk apparatus. ( Fig. 1) The change in the cooling water plate circuit in the cream maker should correspond to the large amount of raw milk, ie the normal flow speeds (v = D, 3 to 1 ^m / s) must be observed. Generally valid circuit suggestions are not possible here, because too different plate types are used. In general, the following information would also be possible: The number of parallel paths in the cooling water system should be changed linearly, as is the relationship between the amount of cooling water used previously and the amount of raw milk. A new raw milk pump may also be necessary, as the increased back pressure in the raw milk area (from pump to separator) causes this. Here, however, the existing pump can usually be used without any disadvantages, since surcharges for increased back pressures are taken into account when calculating the pumps.

When installing new heating systems, the appa rative effort less than with the old procedure, since now the heat exchanger-freezer and boiler milk heaters can be dimensioned smaller.

In a case of the new procedure (new installation) savings (energy and cooling water costs) of 1 Pf per kg of curd cheese.  

Claims (3)

1.Procedures for optimal energy utilization during lean milk heating in dairies where the skimmed milk leaves the heating apparatus at temperatures of more than 15 ° C (e.g. kettle milk in cheese factories), in short: OKMEV (optimal kettle milk heating) -Procedure), characterized in that the entire amount of cold raw milk is used to pre-cool the cream. ( Fig. 1) 2. The method according to claim 1, characterized in that the entire amount of boiler milk recooled in the heat exchanger is used for pre-cooling the cream. ( Fig. 2) 3. The method according to claim 1 and 2, characterized in that the specified amounts of milk is used for pre-cooling the resulting tube frame. ( Fig. 3).