Electricity + Control

Food and beverage manufacturers in South Africa, while facing stringent legal requirements for food safety, are under pressure to optimise their processes to deliver high quality, cost-effective products to an increasingly discerning market.

                   The FMR62 ultrasonic level transmitter.

A well-known South African beverage company with a long and successful history in the local dairy and fast-moving consumer goods industries, recently faced an engineering challenge in optimising its mixing process.

This company’s presence in the beverage sector has been entrenched by its winning several taste and quality accolades, hence it has an established reputation which it is committed to upholding. With a basket of established brands and a requirement for frequent change-overs in production, product losses were becoming a financial burden and raised the potential for unintended environmental impact from the manufacturing floor.

Process optimisation and resource savings are central to the corporate culture at the manufacturing facilities. The maintenance manager focuses on improving overall plant reliability without compromising on product quality and, at the same time, keeps a close watch to limit production-related environmental impacts.

At the plant the performance of the existing level transmitters in the mixing tanks was proving unsatisfactory. The installation involved turbulence, tank intrusions, an agitator and a degree of foaming in a vessel with a conical base. The capacitance type probes in use did not measure sufficiently accurately to the bottom of the mixing tanks. This resulted in product being left behind when transferring to the buffer tanks. The net effect of this measurement problem resulted in high product loss and high effluent costs. The production team needed new devices to deliver improved accuracy with a reliable and repeatable measurement.

Endress+Hauser was approached to assist in resolving this process problem with a trial unit that would be tested alongside other competing brands. This was an opportunity to showcase the performance capabilities of its 80 GHz free space radar level transmitter. Endress+Hauser offered the FMR62 to the customer and a defined assessment matrix was developed. Three test units from different manufacturers were run on the mixing tanks and assessed on the following criteria, as determined by the customer.

  • Process fit and integration

  • Ease of use

  • Service and support

  • Performance

  • Total cost of ownership

The solution provided by Endress+Hauser proved to be the best overall, scoring highest in the evaluation. The performance demonstrated by the unit allowed the customer to determine minimal levels that accumulated in the vessel via the sprayball during cleaning in place (CIP). This offered the customer a new degree of traceability and the capability to ascertain from a single trend view if a CIP has been carried out between batches.

When reviewing the results of the trial, the factory’s maintenance manager emphasised how impressed he was with Endress+Hauser’s ultrasonic level transmitter’s accuracy at low levels. His initial assumption was that the level transmitter was drifting at the zero point after the tank was emptied. However, on closer inspection it became evident that the FMR62 was detecting the residual from the sidewalls that was pooling in the vessel cone. None of the other trial devices had revealed this inherent process condition.

The manager further commented that this measure represented excellent accuracy in the most difficult part of the tank (the cone). The accuracy delivered was better than he had hoped for and this could aid operators to ensure the tanks are truly empty before starting a new production batch. This positive feedback has resulted in the site planning a migration strategy for their mixing tanks that will leverage the technology benefits of the FMR62.

Enquiries: Anban.pillai@za.endress.com