Slurry role for dosing pump

Neutralac SLS45 high strength liquid lime from Lhoist UK is proving a solution for process plants requiring improvements in their effluent treatment procedures. This is not only due to the properties of Neutralac (45% solids by weight, 300 Cps viscosity and 5 second KIWA reactivity), but the ability of Lhoist to supply customers with a field trial equipment package tailored to specific needs.

The delivery technology is a Watson-Marlow 720UN/RE high flow dosing/metering pump and Lhoist has already acquired six since the project started in 2012.

Derek Thompson, product manager, says: "Neutralac lime suspension is fairly thick and the pumps are often sited outdoors. The Watson-Marlow 720UN/RE is a work of art – it’s tremendously flexible yet extremely robust and reliable. In addition, they are easy to hook up with pH controllers – either our own meters or those used by the end user.”

The 720UN/RE is used to pump Neutralac from storage vessels into effluent treatment plants for pH control. Flow rates vary from 10 to 1500 l/h, which is controlled via a 4-20mA signal from a pH meter. Run-times vary tremendously but, according to Derek Thompson, the impressive performance of the system often imparts a reluctance to change. As a result, the plant is retained, leading to ongoing sales of Neutralac, as well as the sale of a Watson-Marlow 720UN/RE pump.