Vacuum Reduces Maintenance Effort and Energy Consumption in Cheese Production

One vacuum pump instead of five, more than 50% energy savings and significantly reduced maintenance costs: These are the results that the DMK Group’s largest cheese plant in the north-western German municipality of Edewecht is pleased to report since putting a new vacuum system from Busch Vacuum Solutions into operation. In addition to products for food retail market, the company produces cheeses for large-scale industry in 15 kg blocks.

These 50 cm long, 30 cm wide and 10 cm high blocks of cheese are called Euroblocks and are prepared for transport in the company’s packaging hall. For this purpose, they are automatically pushed into bags by the four packaging machines in the hall. In order to open the bags in preparation, four suction cups on each packaging machine draw up the undersides of the bags. This process is made possible on all four packaging machines by a single MINK claw vacuum pump from Busch Vacuum Solutions. It is part of a vacuum system designed specifically for this process.

Supplier to the German food retail market

As Germany’s largest dairy cooperative, DMK is one of the most important suppliers to the German food retail sector. With more than 20 locations in Germany, the Netherlands and other countries, the company processes around 5.5 billion liters of milk per year, which comes from more than 4,400 farms. For its main brand MILRAM, the DMK Group produces cheeses such as mild Gouda, nutty Burlander and hearty Müritzer. It also produces a wide range of other dairy products. The repertoire ranges from German butter to quark, yogurt, cream, and condensed milk, and even ice cream and baby food.

One vacuum pump replaces five others

The MINK system supplies vacuum to all four packaging machines simultaneously with a single active vacuum pump. Previously, four individual dry-running rotary vane vacuum pumps were used to package the cheese blocks, one on each packaging machine. These rotary vane vacuum pumps ran at full rotational speed for up to 24 hours seven days a week and, at 75 dB(A) per vacuum pump, were very noisy. Standing in the packaging room therefore exposed employees to considerable noise.

The air in the packaging room is humid and salty, as salt plays an essential role in cheese production. This resulted in increased corrosion and higher wear of mechanical parts in the vacuum pumps. "That’s why the vanes in the rotary vane vacuum pumps had to be replaced twice a year, and there were also repeated total losses," explains Georg Backer, Maintenance Team Leader, who was looking for a quieter, more energy-efficient solution that was less susceptible to failure.

High energy savings and low maintenance

Vacuum specialists from Busch recommended the latest claw vacuum technology to the customer, the efficient MINK MV. Thanks to its high performance, it can supply the four packaging machines with vacuum on its own. In addition, they made the decision to place the vacuum pump in a separate room. This measure significantly reduced employees' noise exposure – even though the MINK MV is already comparatively quiet at 68 dB(A). It also protects the vacuum pump, which is no longer exposed to the same amount of salty humidity as in the packaging room. In addition, the MINK vacuum system from Busch incorporates a standing filter upstream of the vacuum pump. Due to its vertical alignment, it takes up little space, is easy to clean, and is protected from damage from contamination. However, the Maintenance Manager is particularly pleased with the energy saved by the new MINK system. “Compared to rotary vane vacuum pumps, we now consume at least 50% less energy,” summarizes Georg Backer.

Thanks to the contact-free operating principle of the MINK, it does not require any lubricants or operating liquids in the compression chamber, so there is no wear and tear that could negatively affect performance. As a result, MINK vacuum pumps are particularly energy-efficient, cost-saving, and provide nearly maintenance-free operation. This is also evident at DMK, where no vacuum pump failures have occurred since the vacuum supply for cheese packaging was switched to the new system. The MINK system has therefore also significantly reduced the maintenance effort of the vacuum supply for Georg Backer and his colleagues. "Previously, we had to do ten repairs a year, and we had to buy an average of five new vacuum pumps. Instead, we now only have to perform maintenance once a year at most and yet we have zero failures," says the maintenance team leader.

In addition, the MINK MV used at DMK has an intelligent speed-controlled drive unit. This means that, when the bags used to pack the cheese are first pumped down, the vacuum pump's motor runs at high rotational speed to extract as much air as possible. When the pressure in the bags drops, the rotational speed of the pump motor decreases. This consumes less energy than an unregulated vacuum pump, which has a motor that always runs at full rotational speed. This further minimizes energy consumption and operating costs.

Additional operational reliability due to a second vacuum pump

The new MINK system operates seven days a week, up to 24 hours a day. To ensure a continuous vacuum supply at all times, it contains two identical MINK MVs, almost always with only one in operation. The other serves as a backup. Since the system had not yet been utilized to its full potential, DMK decided to integrate an additional carton erector. This was previously supplied by its own vacuum pump to lift and set up the folded cartons. But even now, the performance of the MINK system is still not being fully exploited, so it could take on further functions.