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Piatto di riso con sottaceti

Nozzles to optimise heat exchange in pasteurisation

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INDUSTRY
Food and beverage industry
APPLICATION
Pasteurization
INDUSTRY

Food and beverage industry

APPLICATION

Pasteurization

PROBLEM

Ineffective sterilization of pickle jars

SOLUTION

Improved spray distribution with Dplus full cone nozzles

The importance of sterilization in the food industry

How PNR Italia has helped save water and energy by improving sterilization in the food industry

The industry

The pasteurization of pickle jars is a thermal process that prolongs food storage, particularly pickles or seasonings and prevents the formation of unwanted bacteria and microorganisms in the stored product.

During the pasteurization phase, the container must first be heated and put down with cold water.

The problem

One of our customers contacted us to solve a problem he was facing in his pickle production line, which was linked to the ineffective heat exchange during the pasteurization process of glass jars.

The customer used hollow cone nozzles because, given the shallow pressure of use typical of these systems, they are the only ones to ensure a well-formed spray cone and a comprehensive free passage. The coverage of these nozzles was uneven because of the hollow cone, which reduces the adequate heat exchange time.

Given the jars’ translation speed, the contact time between them and the hot water flow was insufficient for effective heat exchange. This meant that the temperature inside the jars could not reach the level necessary to ensure proper sterilization.

This thermal shock prevents the formation of microorganisms, such as bacteria, yeasts, and moulds, which can cause deterioration or food diseases.

Piatto di riso con sottaceti

The solution

We carried out a tailor-made coverage study for the customer. We proposed the replacement of the current hollow cone nozzles with new full tangential cone nozzles that had the same technology as our Dplus full cone nozzle and the patented vane.

Our solution offers new full cone nozzles operating at low pressure with a significant free passage. This way, the customer would not have to change the system, and thermal efficiency could be increased thanks to broader coverage.

Studio di copertura

COVERAGE WITH NOZZLES
SPRAY ANGLE 60°

Studio di copertura

COVERAGE WITH NOZZLES
SPRAY ANGLE 90°

Advantages

The benefit was immediate. The better coverage raised the heat exchange and thus allowed, for the same result, to reduce the flow rate and ensure an adequate sterilization process. In the customer’s case, the water temperature was 98 ºC.
Dplus nozzles are the optimal solution in the process line because they generate a balanced spray with uniform coverage and maintain full coverage despite low operating pressure.

But that’s not all. We guaranteed the customer a 10% water saving, which resulted in an electrical saving of 43.06 kW per hour due to the reduced power at the pump, especially for the reduced amount of water to be heated.

Finally, another convenient effect was reduced steam emission, which caused problems with the disposal of the extractor hoods.

Calculations by our engineers have shown average/monthly savings for the customer of around 11,000€

prodotto Dplus

D plus

FULL CONE NOZZLE

Dplus nozzles provide a full cone jet with a characteristic spray angle independent of the input pressure, ranging from 1 to 10 bar.

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