Elektror in the plastics industry

Customised plants often require unconventional solutions.

Elektror fans in granulate dryers

Koch-Technik, a full-service provider of peripheral devices and systems for processing plastics, is a long-standing customer of Elektror airsystems. Our blowers and side channel blowers are the equipment of choice for the large Koch granulate dryers. In this case, there are several requirements that an industrial blower must meet.

Synthetic granules form the basis of many plastic components. The quality of the resulting moulded part is now more than ever dependent on pre-drying of the granulate. Koch supplies dryers that extract excess mois-ture from the granulate. If the granulate is not perfectly dried, this can result in striation, em-brittlement, blistering or impairment of strength during the subsequent processing. Therefore, Koch employs gentle and controlled granulate drying using a patented system during plastic production.

How a granulate dryer works

A dryer for synthetic granules consists of two cycles, the drying cycle and the regeneration cycle. Both cycles feature Elektror products.

The drying cycle

The blower in this cycle pumps dry air into the granulate vessel. There, the air absorbs mois-ture from the granulate and is then pumped out from the granulate to a downstream desiccant container. There, it is dehumidified again. From here, the cycle begins again. The blower is used to move the cycle.

The regeneration cycle

Once the desiccant in the drying cycle has become saturated with moisture, it switches to the regeneration process. During regeneration, a blower pumps hot air into the desiccant container. This releases the moisture from the container and it is then dispersed into the surrounding area. During this regeneration cycle, a second desiccant container dehumidifies the air from the drying cycle.

The actual drying process is controlled on the basis of the dew point. The drying containers are also equipped with a ECO system controller patented by Koch. The combination enables energy savings of up to 40%. This controller reacts individually to the respective quality of the granulate or synthetic pellets.

A flexible drying system requires flexible fans. Thanks to the frequency inverter, the Elektror fans can be regulated according to demand. This is a major advantage if the volume of dry air in circulation fluctuates significantly or if less than maximum capacity is required.

However, it is not just the frequency converters that contribute to this energy-saving drying, but the fans in general. All of the Elektror fans used conform to the Energy-Related Products Directive. The Energy-Related Products Directive sets minimum requirements and mandatory li-mits for fans. Elektror fans comply with the Energy-Related Products Directive 2015.

A conversation with Damir Brkic, Pro-duction Manager for mechanical systems in plant 2 at Koch, reveals additional advantages of the Elektror products. „Our granulate dryers operate at very high temperature ranges. This means that the inside of the dryer can get pretty hot and the dryers are running continuously. As a result, all of the components installed must be extremely robust. To my knowledge, the Elektror fan fitted has never failed.“ The ball bearings in Elektror fans are lubricated with a high-performance grease and are designed to withstand high temperatures. The highly dynamic balancing of the impellers reduces oscillations in the products and limits the level of vibration and noise. The frequency converters also make life easier for Mr. Brkics: „It is easier for us to service our extensive overseas custo-mer base because fans that can be con-trolled by frequency converters are ea-sier to adapt to country-specific voltage supplies.“