Pressurised Dewatering of Sugarcane Press Mud for Logistical Transport Efficiency and Industrial Reuse

Abstract

Press mud, a by-product from sugar milling, has agronomic soil input value, but its transport distance from the mill site is limited by its high moisture content (75–80%). This results in over-application close to the mill, concentrating nutrient sources from a wider harvest region, and has potential for environmental harm. Moisture reduction methods have traditionally focussed on centrifuge techniques, but pressurised systems have been shown to have benefit in other waste industries. This work investigates a press-based system for the dewatering of press mud with sequential loading. Subsequently, the solid and filtrate components were assessed for agricultural land application value, with the solid further assessed for livestock feed value. The observed weight reduction was between 20 and 50%, which increased the viability of land application. Results suggest a combination of mill by-products (PM, ash and bagacillo) could result in a product that is more suitable for dewatering. The separated solids had potential for both land application and livestock feed, while the filtrate nutrient value was observed as low.