Plastics made to order – thanks to level and pressure measurement technology from VEGA

Produced according to individual recipes that best meet customer requirements, Renolit's plastic films as well as other products represent the highest level of functionality. This requires highly accurate dosing of the base materials – such as polymers, additives or colourants – under consistent process and ambient conditions. Since plastics production is very energy-intensive, measuring energy consumption is becoming increasingly important. VEGA sensors for level, flow and pressure play an important role here.

At Renolit, raw materials are stored in intermediate bulk containers (IBCs) for liquids with a capacity of 1,000 litres or in large outdoor silos for bulk solids with a capacity of up to 200 cubic metres. The levels have to be monitored with millimetre precision, without the need to open or modify the containers. Radar-based level measurement technology is the solution of choice here. As a universal radar sensor, the VEGAPULS 6X monitors a wide variety of measuring points and ensures that the correct quantities of each component are supplied at all times.

Since Renolit started using VEGAPULS 6X universally in its storage facilities, procurement has become much easier for the company. Although the configuration and the material in the silos vary depending on the specific product requirements, it is always important that the materials used are optimally stocked so that production runs efficiently and without interruption. 

But optimal raw material storage isn’t the only thing that offers considerable savings potential. Direct measurement of energy use is also becoming increasingly important at Renolit. The company has set itself the goal of achieving CO2-neutral production by 2045. More than 300 meters record the electrical energy consumed in PVC film production. In the temperature control units of the calender rolls, for example, precise pressure instrumentation in the form of three VEGADIF 85 differential pressure transmitters is used to accurately monitor the flow of heating water. This ensures that the process runs under optimal conditions and thermal energy consumption is precisely oriented to demand.

The differential pressure transmitters are each mounted with a gate valve, so that they can be serviced or replaced at any time without having to interrupt the ongoing process. The special dual-chamber electronics offer further potential for savings. With two VEGADIF 85 sensors, the static pressure and the differential pressure can be measured simultaneously. This is an advantage, because the static pressure is an important component for optimal process flow in the calender, which, thanks to the deployed pressure measurement technology, is now monitored without additional sensors.

Just the new software modules alone, which have optimised the standby mode of all electrical devices, have allowed Renolit to reduce energy loss by 60 percent. To reduce consumption even further, the company has left no stone unturned when it comes to optimising remaining energy guzzlers like cooling and heating processes. Renolit will continue to rely on VEGA’s level and pressure instrumentation in the future – and thus on exact, reliable measured values that make the end products traceable and indicate where and when the plastics were produced and at what temperatures and speeds.