Diffusers are extraction vessels used in the sugar industry to leach sucrose from beet cossettes or cane by countercurrent contact with hot water. Sliced material moves against the flow of increasingly concentrated juice, so diffusion continuously draws sugar out of the cells. Efficient diffuser operation depends on cossette quality, temperature, pH control and retention time, and it determines extraction yield and juice purity for all downstream refining. Operators monitor brix profiles along the vessel to keep performance on target. Maintenance focuses on screens and seals, since wear in these parts quickly degrades extraction performance.