Energy costs practically halved

Filling about 1.5 million bottles of mineral water a day, Mineralbrunnen Teinach GmbH was the first mineral water plant to be granted the Assured Sustainability – Investment in the Future seal of approval for sustainability in ecology, economy and social competence in 2013 by the private German Institute for Sustainability and Economy.

Knowing that overheads for materials and the price of energy are among the biggest cost drivers in production, Teinach charged the KHS Group with the modernisation of its PET bottle filling line. In the course of the process the systems supplier greatly improved the level of energy efficiency by optimising the heater boxes on the PET stretch blow moulder in particular.

At its plant in Bad Teinach, just under an hour’s drive west of Stuttgart, the mineral water bottler achieves an output of about 150 million bottles of water and soft drink per annum, a third of which are made of PET. Preform heating consumes a lot of energy and is thus a relevant factor when it comes to the operating costs incurred during the manufacture of PET bottles.

One of Michael Schanz’s main tasks, as head of engineering at Mineralbrunnen Teinach GmbH, is thus to constantly monitor the energy efficiency of the lines. He was therefore immediately enthusiastic about the new possible savings offered by KHS’s InnoPET machines. KHS analysed the savings potential of the InnoPET Blomax Series III together with the engineers from the mineral water company.

The stretch blow moulder in Teinach has been in operation since 2007. “Over the last nine years the machine has given us wonderful service. KHS then showed us that with little effort we could improve further on our levels of energy efficiency,” Schanz explained. After a maximum of two days the machine would again be ready for operation, yielding savings of up to 50%.

“After we’d discussed the details, it only took a few weeks before conversion started.” This was possible as KHS was able to make use of a tested development from its energy-saving solutions product module.

Optimised heater box geometry with ceramic reflectors

The upgrade primarily consisted of converting the heater box on the Blomax Series III Compact where the PET preforms are heated for the downstream stretch blow-moulding process.

Frank Goebel, head of service engineering at KHS, highlights the development of the past few years: “We have almost 600 Series II Blomaxes in operation worldwide. We aim to continue to support the operators of these durable machines even after many years of service.”

At Teinach this specifically means saving over 40% in energy by converting the heater box which KHS achieved by adding new reflectors made of modern ceramics to the heater boxes and precisely adjusting the geometry. Thanks to their special design the physical properties of the ceramic elements have a very positive impact on the energy distribution, resulting in less energy being needed to heat the preforms. The reflectors and infrared emitter are also built so that the sensitive bottle thread area is not unnecessarily heated. The amount of cooling in this area can then be reduced, thus saving Teinach even more energy. This higher efficiency often also makes it possible to shorten the heating segment, explained Goebel. If fewer heating elements are required in the heater, the infrared emitter consumption also drops as a result.

KHS usually converts the heater boxes on all Series III Blomaxes in a maximum of two days. KHS process engineers make the fine and final adjustments during the start-up phase so that disruption to production is kept very short. Teinach’s head of engineering is suitably satisfied with his company’s decision to invest in this new feature.

“We’re always trying to save energy to cut costs and protect the environment,” stated Schanz. The bottler demonstrates this outside the production shop, too, through its long-term cooperation with the Central/North Black Forest Nature Park for the conservation of the unique local countryside, for example. Or with its system of energy management, certified according to ISO 50001. “We can simply read off the history of the heating costs for the modernised system on the electricity meter and document the significant savings,” he claimed. Schanz also added that KHS converted the line quickly and competently without affecting system operation. Since the end of last year the revamped heater box has been running without any problems whatsoever.

Through the amount of energy saved, investing in a modernisation of the InnoPET Blomax Series III pays off for users after one to three years depending on the line’s capacity utilisation and the price of electricity. KHS also offers the conversion for both versions of the Blomax Series II: the Modular or the Compact. “For many companies, energy-optimised PET stretch blow moulders are an excellent way of reducing production costs,” said Goebel. He expects more orders for this sustainable KHS conversion product in 2016.

Image: The heater boxes are distinguished by new reflectors made of modern ceramics and a precisely adjusted geometry.