Hindustan Dorr-Oliver Limited

Brown stock washing system

HDO Brown Stock Washing system is a well-designed closed counter current system comprising of three or four washing stages with salient features like efficient removal of dissolved solids from pulp and efficient recovery of strong black liquor. HDO can design and supply brown-stock washing system to handle variety of raw material, various pulping processes and capacities. The system comprises of brown-stock washers, intermediate shredder-repulpers, final conveyor- repulper, blow tank agitators, black liquor filter, dilution nozzles and mechanical foam breaker.

HDO's introduction of ripple deck design replacing conventional wire-wound design provides tangible benefits like increased consistency of pulp, decreased soda loss and higher weak black liquor concentration. The air-doctor type discharge mechanism has enhanced life of filter wire- cloth. The two point suspension valve has advantages in achieving better pulp consistency and provides quick access to valve internals for easy maintenance. A well designed seal tank ensures effective separation of foam from the black liquor which is subsequently suppressed by means of a foam breaker.