Equipment Description
The screw digester is a critical equipment in the chemi-mechanical pulping process, primarily used for conveying, compressing, and preliminary cooking of fibrous raw materials such as wood chips. Inside its screw conveyor, fibrous materials are progressively compressed while soaking in precisely dosed cooking chemicals and steam. This controlled environment softens lignin, weakens fiber bonds, and preps materials for refining-boosts the pulp quality and efficiency.

Equipment Parameters

Model	LHLXZZ-1600	LHLXZZ-2000	LHLXZZ-2500
Spiral Diameter(mm)	1600	2000	2500
Spiral Length(mm)	12000
Conveying Angle(°)	0-13.5
Dwell Time(min)	15-20
Spiral Rotational Speed(r/min)	0.5-2r/min
Capacity (t/d)	100-140	150-200	250-300
Motor Power (KW)	15KW	18.5-30KW	30-55KW

Working Principle

Inside the screw digester, a rotating screw shaft moves material along the axial direction. The spiral design doesn't just push material forward-it creates a rolling, mixing action as it travels. This constant tumbling ensures thorough contact with steam and chemical liquid medicine, assuring fast, even heating and reaction throughout the digester.

Equipment Usage

Raw materials (e.g. wood chips, bamboo chips, and wheat straw) can be precisely controlled during the cooking process by setting the temperature and rotational speed of the equipment, adjusting the residence time and reaction temperature of the materials in the cooking tubes, to ensure materials cooking exactly as required for different products.

Equipment Properties

The screw digester features simple structure, efficient continuous production, uniform heating, small footprint, precise process control, no pressure and no danger, making it suitable for the continuous production of current chemi-mechanical pulp.

Application

The screw digester is mainly applicable to the pulp and paper, biomass, chemical, pharmaceutical and other industries. When combined with other equipment for production, it is an indispensable cooking equipment in the industry.