In the chemical pulping process cooked pulp, referred to as brown stock, discharges from the digester. Cooking liquors (spent liquor) is separated from the pulp for recovery. The use of a rotary vacuum washer is the typical method. Other forms of diffusion washing are also used. Wash water, sprayed onto the pulp stock through nozzles, is heated to around 180ºF to enhance the dispersal of cooking liquor.