Peristaltic pumps transform dye control in papermaking

Chroma Logic began in the USA as a partnership in 2000 when two technical employees decided to leave a very large paper company and start their own venture. Their past experience had taken them to pulp and paper mills all over the world, and one thing became increasingly evident: each machine they scrutinised suffered chronic and unnecessary losses due to dye metering equipment. Even machines with new and very expensive dye systems fell into disturbing patterns of 'lost time for colour' within as little as a year after installation. Worse still, most mills were generally unaware of just how much lost time their dye systems were costing them.

Jason Peterson and John Mara observed the benefit of Watson-Marlow peristaltic pumps while designing dye systems at their former company, but saw the need to integrate the metering pumps into a complete and optimal systems approach for colouring paper. Their focus was on minimising the transition time between colours, greatly simplified maintenance, and fewer man-hours for colour process management. The robust industrial construction of Watson-Marlow peristaltic pumps, when married to Chroma Logic's innovative dye transfer and dilution technology, has yielded enormous advantages in paper machine colour process efficiency.

Jason Peterson (now president of Chroma Logic) and John Mara (director of engineering) have proven their innovative metering equipment, with over 20 installations throughout the USA and Canada. Today the company has sites in Pennsylvania, New York and Paris.

Wide flow range

Chroma Logic's dye systems incorporate the Watson-Marlow 520DuN and 620DuN peristaltic pumps. These are used in the company's automated dilution, tinting, basic dye, deep colour and white paper systems. Their vast flow range is highly suitable for the Chroma Logic application. The company likes the fact that the pumps are "instantly expandable to cover enormous flow ranges and able to provide trouble-free metering of both corrosive dyes and pigments", adding that they are "digital, precise and virtually pulse-less."

In peristaltic pumps, nothing but the hose or tube touches the fluid, thereby eliminating the risk of the pump contaminating the fluid or the fluid contaminating the pump. They work by compressing a tube element between rotating rollers. In between each roller pass, the element recovers to create a vacuum and draw in fluid, giving the pump its positive displacement action, preventing backflow and eliminating the need for check-valves when the pump is not running. The technology is useful for slurries, viscous, shear-sensitive and aggressive fluids.

The Watson-Marlow pumps are compatible with all gauging control equipment used by Chroma Logic, and all are supplied with a five-year factory warranty. This is important because the paper industry is under constant pressure to produce higher quality paper product appearance more competitively than ever before.

Chroma Logic Dye Systems are designed to precisely and continuously control the addition of colour and other chemistry to the papermaking process while yielding benefits that include: faster colour grade change times; dramatic reductions in maintenance; reduced set-up time, complexity, and man-hour requirements; improved colour quality with fewer internal colour-rejects; and substantially simplified installation.

Features such as complete redundancy of critical components, automated dilution that makes running dilute dyes as simple and trouble-free as running neat dye, and flexibility to instantly send incompatible dyes to multiple addition points, demonstrate that Chroma Logic equipment is designed to fully address all concerns associated with managing the colour process.