Electricity + Control April 2019

FLOW MEASUREMENT + INSTRUMENTATION

The dairy industry for years has faced the challenge of accurate flow measurement in receiving and offloading as well as processing applications. Endress+Hauser pre- sents the case in which it assisted one of its dairy industry customers in the West- ern Cape to improve the accuracy of flow measurement – and thus reduce milk losses – in the processing area of the plant. Accurate flow measurement in dairy production

The varying degrees of entrained gas in dairy pro- cesses make accurate flow measurement a challenge in the industry. Take Note!

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O ften, the most common cause of inaccu- racies in flow measurement in dairy pro- duction is the degree of entrained gas, which adversely affects the fundamental measur- ing principles. Coriolis mass flowmeters are usual- ly only used for single-phase fluids, that is, either liquids or gases. Production facilities tend to deal with this challenge by implementing ‘correction factors’ in their control systems, to compensate for the discrepancies. While the flowmeters are accurately calibrated and certified, the complete loop integrity is compromised as a result of the correction factors that are introduced. The challenge An Endress+Hauser customer in the Western Cape approached the company to support its fa- cility with ‘fair and equitable’ measurement. This would enable the dairy producer to maintain its sound relationship with the local farmers. The company embraces a culture of innovation to meet the changing needs of consumers and is well known for producing a wide range of cheese and dairy products that have earned a reputation

for quality and flavour, winning several local and international awards. Its state-of-the-art manufac- turing facility is located near local dairy farmers to ensure milk is delivered to the factory with mini- mal delays. The high quality milk is sourced from farms that raise free range cows. The dairy manufacturer was looking to reduce milk losses it had identified in the processing area of its plant and to manage the costs of losses in- ternally, rather than simply passing them on to the consumer. This was in line with its drive to improve operational efficiencies and optimise processing, which it recognises as key to its continuing success. Endress+Hauser was approached for a solution to reduce the milk losses in the processing area. The existing flowmeters were proving to be inac- curate and resulted in the company encountering major losses. This is a challenge that is widely experienced in the industry because of the varying degrees of entrained gas that can be found in dairy process- es. Mild protein and fat structures like milk tend to entrap air easily, causing errors in measurement of batch offloading and processing.

18 Electricity + Control

APRIL 2019