Sweden's largest dairy cooperative employs digital dosing pumps for the plant's clean-in-place system.

Based in northern Sweden, the Milko dairy company develops and markets natural dairy products. It is the largest dairy cooperative wholly owned by Swedish farmers and the fifth-largest food company in Sweden.

Committed to ideals of natural food, openness and innovation, the Milko team decided to employ a dosing pump range for the plant's clean-in-place (CIP) system. The pumps combine precision with ease of use, ensuring the most sanitary environment possible.

Saline solution used to float cheeses is sanitized by CIP system using a dosing pumpImage 1. Saline solution used to float cheeses is sanitized by CIP system using a dosing pump (Courtesy of Grundfos)

The Situation

CIP systems are ideal in industries where hygiene is vital and contamination must be avoided at all costs. These systems allow plant personnel to efficiently clean tanks, pipes and process lines without dismantling equipment, saving time and money.

Precise dosing pumps can further streamline the CIP process by adding only the necessary additives, which reduces flushing of the system.

For a dairy company, superior hygiene is essential for maintaining top-quality products and efficient operation. At Milko, the vats used to float cheeses in saline solution require daily cleaning to ensure proper hygiene.

Before the installation of the dosing pumps Milko's CIP system was fully manual, which meant all additives were incorporated by plant employees. To ensure efficient and reliable dosing of additives to the CIP system, the Milko team decided to change the system from fully manual to semi-automatic.

The Solution

Milko installed a dosing solution to dose acid and lye in exact amounts. The Milko employees can easily set the pump to discharge the exact quantity of dosing liquid required in the application. The pump display indicates the setting of the pump in millimeters per hour (mm/hr) or liters per hour (L/h), as well as pulse or batch. Icons easily identify the operation mode.

The pump can run at full capacity simply by pressing the 100 percent key. This means the pump is fully primed for the next cycle. With a turndown ratio of 1 to 1,000, the pump is accurate to the smallest dose. The pump's intuitive control panel and multi-lingual, five-button interface allows the Milko team to specify the dose required and let the pump take care of the rest. The team also has full control over the speed, acceleration and position of the diaphragm, allowing the additive to be applied evenly and precisely.

The unique dosing principle of the digital dosing pumps allows the dosages of additives to be performed with minor pulsations and high accuracy. The pump's diaphragm is mounted directly on the motor-driven connecting rod. This construction makes it possible to control the speed of the diaphragm through every discharge and suction phase.

The Outcome

"The new pumps in the CIP system have worked every bit as well as the others in the plant," said Lars Rudh, operations engineer at Milko. "We already had dosing pumps elsewhere in our plant and were very pleased with them, so naturally we wanted to use them in our CIP system as well."

Milko continues to be satisfied with the performance of the pumps. "Well, quite simply, they work very well. And they're very easy to use—you know straight away what to do to achieve the best results. In fact, we're planning to put in more pumps in other parts of our system."