How does shear rate generated by a bitumen emulsion pump affect droplet size stability?

Pump shear can both help and harm. Moderate shear may reduce droplet size slightly, but excessive shear can heat the emulsion, strip emulsifier from droplet surfaces, and create coalescence that destabilizes the product. High shear zones at valves, narrow fittings, or cavitation points often cause localized breaking. Stability improves when pumps operate at low speed with adequate suction head and minimal throttling. A stable droplet size distribution is preserved by smooth flow paths and avoiding recirculation loops.