Optimising Milk Powder Production in a Holistic Approach
The Miraka Pavilion8 solution was implemented in phases to effectively introduce model predictive control technology to operators while delivering value. Real time key performance indicators were deployed quantifying the value being delivered as each unit was commissioned.
The evaporation process was optimised in the first phase. Variability was reduced and total solids targeting was improved. The evaporator total solids target was lifted resulting in better thermal efficiency across the evaporation and drying stages and increased capacity.
In the second phase spray dryer model predictive control was commissioned.
“Deploying model predictive control on Miraka’s spray dryer allowed us to improve yield through closed-loop moisture control combined with targeting an increased powder moisture," explained Kerryn Sakko, Pavilion senior application engineer, Rockwell Automation. Capacity was additionally maximised by pushing the process safely to constraints.“
Implementation of multivariable model predictive control on the standardising process was delivered as the final phase of the solution. Use of multivariable models for liquid composition control combined with inferential models for tracking composition through the entire drying process resulted in reduction of protein and fat variability in the final powder.
Additionally the liquid composition controller included additional objective functions to maximise use of lower cost standardising ingredients.
Training sessions, which utilised the advanced analytics capability of the Pavilion8 system, facilitated operators quickly learning to optimally use the system and additionally streamlined site acceptance tests.
Measuring Process Improvement
Through consultation with Miraka, a set of parameters were identified that would provide information about the effectiveness of the process improvement.
The identified parameters were:
- Quality (powder moisture yield)
- Evaporator solids (plant throughput improvement)
- Dryer thermal efficiency (dryer capacity improvement)
- Reduction in energy per tonne of product (cost reduction)
- Protein and fat optimisation (yield)
The Pavilion8 solution provided Miraka an exceptional result. A capacity increase of more than four percent was achieved during the peak season, moisture targets were raised by 0.04 percent, and improved protein and fat control provided the potential to reduce fat plus protein giveaway by more than 100 tonnes per year.
In addition, optimisation of the evaporator solids and drying profiles resulted in an estimated energy savings of greater than one percent per tonne of milk powder during peak production
According to Paul Trewin, general manager operations at Miraka, “The excellence and innovation values of the Miraka Powder Plant team who delivered this project alongside Rockwell Automation greatly exceeding expectations was brilliant to observe.
Rockwell Automation, Inc. (NYSE:ROK), the world’s largest company dedicated to industrial automation and information, makes its customers more productive and the world more sustainable. Headquartered in Milwaukee, Wis., Rockwell Automation employs approximately 22,000 people serving customers in more than 80 countries.
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