Scaling prevention in zinc sulfate pipework

Scaling in leiding

One of the most costly aspects of a production process is the interruption of work due to unexpected maintenance. Clogged pipework and plate coolers are a chronic problem for the process industry. Scaling, but also biofouling, lead to more downtime and costly cleaning activities. These additional costs are often already included in a special budget, which reduces the margins on production.

A European zinc manufacturer has approached LSC to jointly tackle the scaling problem. The removal of the scaling has until now been done by means of high-pressure cleaning. This process, not without risks, is performed by an external party. There is so much scaling throughout the entire plant that a team from this party is always present full-time. Pipework that is critical in the production process and becomes unexpectedly clogged always has priority.

To avoid surprises, one pipe in particular is cleaned preventively every 5 weeks. The ultrasonic system is installed on this pipe. Prior to the installation of the ultrasonic system, the pipe was inspected by means of an endoscope. The scaling is present to a large extent.

After installing the ultrasonic antifouling system, the pipe was cleaned again. After 5 weeks the pipe was inspected again with an endoscope. The pipeline has remained virtually free of scaling. With these results, there is no danger of a reduction in production output due to scaling.

LSC has glued transducers that introduce ultrasonic vibrations. The sound is ‘structure borne’ and spread through the stainless steel of the pipe. The pipe functions as an amplifier of this sound and induces cavitation at a microscopic level. This interrupts the crystal formation of scaling, making it less able to adhere. As a result, the pipe can be used longer without downtime due to congestion or a reduction in flow.