After receiving over 10% production increase on whey powder they decided to boost their production optimization by installing NAPCON Controller also to their milk powder production line at Valio’s dairy in Seinäjoki in 2015 which resulted also 10% production increase. Valio is currently planning to expand optimization to their other production plants as well.
Valio produces demineralized milk and whey powder in large quantities. The moisture content of the final product is adjusted in the final stage of the production line by a spray dryer. This is a very energy-intensive process, and moreover, the moisture content must be controlled exactly, because too large water content causes stickiness of the whey powder from which disturbances and even shut-downs follow. Excessively dry milk powder on the other hand generates more dust, which has a negative effect on product properties and uses excess energy.
“Too large water content makes the powder sticky and disturbs the process”, Vesa Strand, Production Manager of Seinäjoki plant, explains. ”On the other hand, if the powder is too dry it generates dust and uses excess energy. With NAPCON we can allow an increase in the average moisture content in the process and still keep the moisture content of the final powder product very close to its target value under all circumstances."
NAPCON minimizes energy consumption
Since whey and milk powder production is about drying fluids, the process is very energy consuming. NAPCON balances the need of energy within the desired product specifications so that the energy consumption is minimized.
By controlling the spray dryer capacity and hot air streams in an optimal way using Multivariable Model-predictive Control (MMPC), it is possible to keep the moisture content of the final whey powder product very close to its target value in all process conditions and under multiple dynamically changing process constraints. This leads directly to a significant increase of production without any increase of total energy used for heating the drying air. Moreover, the risk for shut-downs due to bag filter clogging is also significantly reduced.
Valio received 10% more production
Another important benefit is that NAPCON Controller can predict the moisture content and in real time adjust the water balance. The optimization adapts even to changes in outdoor humidity. The moisture content is a critical factor especially at the final stages of the production line where a spray dryer removes the last part of the water, while still keeping the valuable properties of the milk or whey.
In milk powder production lines evaporators are used to remove excess water before the concentrate enters the spray dryer. By controlling both of the drying stages simultaneously with NAPCON Controller, even more savings can be gained, and it is possible to ensure that both units continuously are run in an optimal way.
The production optimization significantly increases the production throughput of new products throughout the entire process. Production increase can be achieved without large investments or interruptions in production. In addition, production energy efficiency improves making the investment into NAPCON Controller very profitable.
"Valio ships over 60 million kilos of milk and whey powders annually”, says Antero Ylitalo, Production Manager of Valio Powder Production. “That means we are talking big money when the productivity boosts with more than ten percent without higher energy consumption or costly hardware investments.”