SNF’s customer found that washing a particular recycled aggregate gave a severe foam/scum problem. Stable, troublesome, foam/scum is not unusual when washing recycled aggregates. Depending on the proportions of concrete and clay in the feedstock, foam/scum incidence varies from trivial to severe.
The customer was suffering foam/scum overflows, from both the de-sander and from the silt settler. The overflows were unsightly; worse, they had a bad impact on site working conditions. The overflows caused an unwelcome slip hazard, and much extra house-keeping was necessary to clean up afterwards.
In addition to the overflows, there were troublesome accumulations of scum at the settler, which demanded time-consuming, labour-intensive, clean-downs.
SNF was asked by the customer to solve the foam/scum problem. SNF’s Technical Sales Representative worked on site with the customers’ team for several days to do this.
SNF’s product range includes a high-performance antifoam well-established for dealing with exactly this problem. This antifoam gives excellent results suppressing foam/scum at recycled aggregates wash-plants elsewhere – and was successful at this customer’s site too. Specifically, overflows from the de-sander and the settler were fully controlled, and scum accumulation at the settler was held to a manageable level.
SNF’s Technical Sales Representative established exactly what minimum dose of the antifoam was required to cost-effectively control the foam, and demonstrated to the customer’s site team exactly where and how to dose the antifoam for best effect.
The customer bought a supply of the high-performance antifoam to control the problem, and continues to use the product when required.