The wet end of the machine that produces packaging and graphic grades was equipped with a total of three analyzers for measuring white water consistency of all layers online. The delivery also included two Metso MCA microwave consistency sensors for measuring total consistency after the machine chest. Earlier the white water analyses on BM 2 were carried out in the mill laboratory with water samples taken manually from the production line. Now the analyzers measure white water consistency online. "With the help of the new white water consistency measurements, we are able to stabilize retention better than before. This decreases machine fouling, in addition to improving runnability and product cleanliness," says BM 2 Supervisor Riku Suurnäkki.The retention analyzer is suitable for all monitoring and closed loop control applications and measures both true ash consistency and total consistency from a continuous sample flow. It can also be used to measure stock flocculation. Retention and ash controls based on reliable measurements provide tools for enhancing production efficiency, improving quality and lowering production costs in a paper or board production process. The application represents the third generation in Metso's retention measurement technology and is based on over 20 years' experience in optical consistency measurements.The Kaukopää production unit is part of Stora Enso's Imatra Mills with an annual capacity of over a million metric tons of board and paper./KB