Valmet's ash crystallization plant will recover valuable sodium salts and remove non-process elements, primarily chloride and potassium, from the Stendal mill's liquor cycle.
May 19, 2026 - Valmet will deliver a new ash crystallization plant for Mercer Stendal pulp mill in Arneburg, Germany. This investment is part of Mercer's long-term vision to further reduce the mill's emissions and improve its performance.
The value of the order will not be disclosed.
The Stendal mill started production in 2004 and currently has the capacity to produce 740,000 tonnes per year of bleached softwood kraft pulp.
According to Valmet, the new ash crystallization plant will contribute to the Mercer's environmental target by helping to close the mill's chemical circulation, reducing the need for make-up chemicals and by helping to extend the recovery boiler maintenance intervals to 24 months and beyond.
"Since the mill started up in 2004, we have systematically invested in improving its performance and sustainability," explained Dr. Martin Zenker, Mill Manager, Mercer Stendal. "Our sustainability efforts are guided by the Mercer vision and values and our long-standing philosophy of responsible business practices that encompass sustainability, safety, financial responsibility, and strong leadership.
"The new ash crystallization plant will help us to further improve both operational and environmental performance. We chose Valmet to deliver this project based on both their technical expertise and our previous joint projects," Dr. Zenker added.
The ash crystallization plant will recover valuable sodium salts and remove non-process elements, primarily chloride and potassium, from the mill's liquor cycle. This reduces plugging and corrosion in the mill's recovery boiler which enables longer intervals between maintenance shutdowns, increasing recovery boiler's long-term availability. Removing these non-process elements with Valmet's Ash Crystallizer design eliminates the need for ash dumping, which in turn reduces wastewater and lowers costs through decreased make-up chemical demand. This solution delivers clear environmental benefits by reducing associated emissions.
The ash crystallizer plant will have capacity to process 140 tonnes of ash per day.
Claus Jensen-Holm, Director, White Liquor and Evaporation, Pulp Mills at Valmet, stated, "We are committed to advancing circularity and resource efficiency. Delivering a new ash crystallization solution to an existing mill is very much in line with these targets and brings several operational and environmental benefits. This project showcases that the ash crystallization solution is not only suitable for new large mills but also brings significant benefits to existing mills. We truly value our cooperation with Mercer and the Stendal mill in finding long-term solutions to optimize the mill's performance."
The new crystallization plant is scheduled to be started-up during the fourth quarter of 2027.
Valmet is a global technology leader in serving process industries, working with customers throughout the lifecycle, delivering cutting-edge technologies and services, as well as mission-critical automation and flow control solutions. Backed by more than 225 years of industrial experience and a global team of 18,500 professionals close to customers, Valmet is uniquely positioned to transform industries toward a regenerative tomorrow.
SOURCE: Valmet