Chamber packaging machines, tray sealers or thermoforming packaging machines use vacuum technology to package fresh foodstuffs hygienically and with a long shelf life. The more such packaging machines are used in a company, and the longer the operating times, the more intensively the energy required and the operating costs of the vacuum supply should be investigated.
The vacuum pump is the core of a packaging machine's vacuum supply. It evacuates the air from the vacuum chamber and ensures that the predefined packaging pressure is achieved as quickly and reliably as possible before the packaging is sealed. Rotary vane vacuum pumps are normally used for the evacuation of the vacuum chamber. With the R 5 vacuum pump series, Busch Vacuum Pumps and Systems has set the global standard for the vacuum supply for packaging machines for more than 50 years, and has continually developed and perfected it since. The latest is the R 5 RD, which was presented at the IFFA 2016 in Frankfurt for the first time. These vacuum pumps offer 20% savings on energy consumption.
For example, if a thermoforming packaging machine is equipped with the new R 5 RD 0360 A (Fig. 1), the annual electricity costs saved during two-shift operation is approx. EUR 1,500 (price of electricity = 0.18 euros/kWh).
Fig.1: The R 5 RD 0360 A is the first size of new, energy-efficient rotary vane vacuum pumps from Busch, which were unveiled at the IFFA 2016.
This new series of R 5 rotary vane vacuum pumps is specially designed for the vacuum packaging of foodstuffs, and can be easily cleaned because the surfaces are smooth, sloped and have a self-draining design. The housing has no cooling fins. Maintenance has been significantly reduced as all of the maintenance elements are attached to an operating side, and only one single air/oil separator must be changed. This means savings on costs even for maintenance.
Reducing thermal load
As a general rule, vacuum pumps generate waste heat that can negatively affect the temperature inside the packaging machine. The waste heat can not only be drastically reduced. It can also be utilized.
An oil/water heat exchanger on an R 5 rotary vane vacuum pump can significantly reduce waste heat and thus reduce the energy costs for air conditioning. Furthermore, the heat exchanger can be used to generate warm water, which can in turn be used as warm water during operation. R 5 rotary vane vacuum pumps can be retrofitted with heat exchangers.
If four packaging machines operate in one packaging room and each is fitted with an R 5 rotary vane vacuum pump with 5.5 kW of motor power, the overall required energy for cooling is approximately 6.0 kW. If the vacuum pumps are operated with a heat exchanger, the energy requirement for cooling is reduced to approximately 1.5 kW. During an operating time of 4,500 hours/year and an assumed electricity price of 0.18 euros/kWh, this results in annual energy cost savings of approximately EUR 3,700.
The use of warm water is not taken into account in this example.
Controlling packaging processes
There are several options to design the packaging process more economically through the use of intelligent technologies for the vacuum supply, ranging from an optimized control system to the use of a vacuum container. Busch has developed approaches according to which a vacuum specialist investigates the existing vacuum supply directly at the customer's site, and analyses this. The specialist can then point out to the customer where there is potential for savings.
The goal is to develop an individual solution for vacuum supply for the customer which can be used to achieve optimal energy efficiency.
Fig.2: Busch central vacuum system in a large meat processing business
Central vacuum supply
Any company that packages foodstuffs on several thermoforming packaging machines, tray sealers or chamber machines should consider using a centralized vacuum supply. Busch is the largest manufacturer in the world of these kinds of centralized vacuum systems (fig. 2) and is the most experienced. With centralization, energy cost savings of 50% and more can generally be expected. Furthermore, performance control can be precisely adjusted to fit the requirements of overall operations. Normally, not all packaging machines run at peak load, so all of the vacuum pumps are not always in operation. Fewer vacuum pumps are required for this than would be the case for a decentralized vacuum supply. Furthermore, centralized vacuum systems offer maximum reliability and safety as all system-relevant components have a redundant design. If a vacuum pump fails or needs maintenance work, full vacuum power remains intact. Busch central vacuum systems can be equipped with various vacuum pumps. In addition to R 5 rotary vane vacuum pumps, dry Mink claw vacuum pumps or COBRA screw vacuum pumps can also be used as components. The investment costs can be reduced by including already existing vacuum pumps in the system installation.
The following chart demonstrates one practical example. In the process of centralizing the vacuum supply, one manufacturer of meat products realized energy savings of EUR 151,000 per year.
Fig.3: Comparison of energy costs for central and local vacuum supply
Vacuum for Packaging
Discover the wide range of options for using vacuum in packaging production and packaging processes.