Diminishing availability of hardwood and increasing prices, have forced major pulp producers to switch over to agro based raw materials like bagasse, wheat straw, rice straw etc. HDO has developed indigenously and designed several continuous digester systems to process these raw materials. This system has various salient advantages over batch digesters in terms of better process control, consistent and uniform quality of pulp, low cooking time, and low steam consumption there-by reducing the production costs and providing flexibility to work with various raw materials. HDO continuous digester system comprises of cross screw conveyor, pin drum feeder, equalizing screw, screw feeder, inlet chamber, digester tubes and cold blow discharger. HDO digester systems can process raw materials to produce pulp ranging from 75 to 250 TPD. This system has been supplied to Bhrikuti, ABC, Mohit , Naini &Yash Paper, etc. and they had surpassed the guaranteed performance figures.