Drying expertise with BITZER intelligence

A variety of industries, including clockmaking, jewellery, automotive, pharmaceuticals, food and surface technology, all use the systems supplied by the family-run company Harter – based in the Allgäu region – when it comes to drying their industrial goods, sludges and foods. Every single one of these systems has been fitted with a BITZER compressor since the start of the year. For one, both companies share the same philosophy – to provide their customers with high-quality, energy-efficient products that are exceptionally reliable: ‘Our systems are always running, day and night. So we can’t allow for any downtime. That is why we switched entirely to BITZER in January 2018,’ explains Reinhold Specht, Managing Director of Harter.

VARISTEP – mechanical capacity control from BITZER
The drying business is not that simple: ‘Every customer requires something different,’ says Specht. ‘Every sector has its own peculiarities and each application is a new task. The aggressive air in electroplating, for instance, is a challenge. With customers in the sludge-drying industry, we have to pay close attention to how much water is extracted.’

Companies dry sludge in order to reduce its mass and thus disposal costs. Lots of water is extracted at the beginning of the drying process, and then less and less thereafter – a good example that demonstrates the importance of functional capacity control in the systems. It is the only way to operate effectively. ‘Frequency inverters don’t allow us to reduce capacity to the degree we would like. VARISTEP, the mechanical capacity control from BITZER, got it just right. It provided us with virtually stepless capacity control for the first time. With it, we can adjust the capacity perfectly based on the goods that need to be dried,’ explains Specht.

Impressed by the intelligent IQ module
The IQ module is another advantage from BITZER. Harter tested the intelligent operating concept from BITZER for the first time with an Austrian customer in late 2016 and has been a believer ever since. The IQ module allows BITZER reciprocating compressors to be quickly, cost-effectively and easily integrated into any system. The modern operating concept reduces the complexity of the systems as well as their potential for faults.

Any problems that do arise can be quickly and easily identified and even solved remotely. ‘If there is a fault of any kind, the customer can download the BEST software from BITZER and connect it to the compressor. This allows us to locate the error and carry out remote maintenance. This saves us a considerable amount of time as, after all, our customers are not around the corner, but scattered all over the world,’ explains Dennis Schiller, Project Manager and the driving force behind the use of the IQ module in Harter drying systems.

Andreas Riesch, BITZER Director of Sales for Germany and Switzerland, adds: ‘IQ modules not only make the system easier to operate and maintain, but also to commission. We preconfigure and test the modules, including wiring and accessories, at our premises, thus reducing the work for our customers: comprehensive compressor control and monitoring are connected to the switch board via a single cable.’

Efficient and future-proof solutions
It is also important to Harter to be able to offer its customers energy-efficient and eco-friendly solutions. For one, this is dependent on the choice of refrigerant. With its low global warming potential of around 600, R450A is the go-to refrigerant at Harter. Furthermore, ‘As our systems also have to withstand extreme temperatures, we have to see which refrigerant is suitable. A key benefit of BITZER compressors is their large application range,’ explains Schiller. ‘That is another reason why we have now switched entirely to BITZER compressors. With the company from Sindelfingen, we can embrace the future with confidence as we know: if there are more new refrigerants in five years, we will be able to use them in our BITZER compressors.’

Harter had built 20 to 25 systems with IQ modules by summer 2018. These feature around 30 to 40 BITZER compressors and liquid receivers, as well as Rotalock valves from the BITZER subsidiary AWA. It is a partnership based on reciprocity: AWA itself uses a Harter drying system, and the BITZER paint shop in Rottenburg-Ergenzingen houses three Harter drying systems.