Posted to News on 21st Feb 2016, 00:00
Metering pumps replace diaphragm pumps at paper mill
A major paper mill in Germany has replaced its existing diaphragm pumps with Qdos models from Watson-Marlow and seen immediate process improvements, including reliability, increased up-time and ease of maintenance when pumping anti-foam agents used in starching operations.different requirements on the couplings.
The Schoellershammer plant in Düren, Germany has been established for 230 years, producing fine paper for the German and international markets. Corrugated board base papers for packaging are also manufactured on another machine known as ‘PM 5’, which currently produces around 225,000 tonnes a year with a weight of 90-170 g/m².
Like all modern paper mills there is a constant focus on the optimisation of production processes, and particularly on pumping. The plant uses hundreds of pumps across its site in countless applications, including lots of lobe pumps and progressive cavity pumps,” confirms Holger Malsbenden, maintenance manager at the facility. “However, we are now increasingly reliant on peristaltic pumps, particularly when it comes to challenging applications and substances that are difficult to transport.” In contrast to many other types of pump, peristaltic pumps are dry-running and self-priming, factors that helped the Schollershammer facility to decide upon the implementation of innovative Qdos metering pumps for dispensing small amounts of anti-foam agent.
The anti-foam agent is required because large amounts of starch are used to treat the surface of corrugated board base paper. The starch is kept in a large storage tank and transferred from there into two tanks ready for treating the top layer and the back. “Too much unwanted foam was developing, so we had to add an anti-foam agent to the starch plant,” explains Kevin Dahmen, the measurement and control technician responsible for the metering station. “A total of three pumps transport the additive to the storage tank, as well as directly into the two other tanks.”
Until recently, this job was done by diaphragm metering pumps, but Schoellershammer was losing patience with what was becoming a growing list of issues. The team discovered that Watson-Marlow’s Qdos metering pump – with its flow range from 0.1 to 500ml/min – was perfect for the application flow rate of 100 to 450 ml/min. Like all peristaltic pumps, the Qdos is a self-priming and dry-running pump, meaning that there is no need for anti-foam agent to be filled by hand after maintenance. What’s more, the pump operates without any ancillaries.
