continuous tubular digester
Introduction of continuous cooking system
Continuous cooking system mainly includes continuous steam pipe, screw feeder, pin drum meter, intermediate tube, heat exchanger and so on. Continuous tubular digester is the main equipment applied for the non-wood fiber pulp making. It can be used not only in chemical pulping but also in chemical mechanical pulping and sometimes in chemical pulping and bio-mechanical pulping. Generally, wet materials are suitable for non-wood fiber, wood shaving and some low density materials.
Advantages of continuous tubular digester
- Continuous production, the productivity per unit area is five times that of traditional cooking.
- Steady consumption of electricity and steam.
- High pulp yield, stable and uniform pulp quality, can be used for pulping, suitable for fine pulp and paper making.
- High degree of automation, high production efficiency, easy to adjust the process, cost savings.
- Flexible liquid proportion adjustment to reduce pollution. Good liquid mixing uniformity, especially suitable for solid-liquid three-phase coexistence of oxygen-alkali cooking process. The consumption of steam in cooking can be greatly reduced, and the amount of black liquor in the extraction section can be greatly reduced, and the burden on the evaporation part of black liquor can be reduced.
- Low building cost and low power consumption. The system does not need multiple series pot bodies, which can greatly reduce the plant height and cost, reduce the energy consumption of the conveyer, more freely automatic operation and lower labor intensity.
- Easy to install and operate, especially to reduce the number of operators. Higher pulp production and smaller area.
- System structure is relatively simple, system maintenance and costs are low.
According to the capacity of pulping system, a continuous tubular digester usually needs one to four cooking tube. The fiber material is fed into the first cooking tube by the screw feeder, driven and stirred by the spiral blade, and the material is fully mixed with the chemical during the slow motion, and then heated by the pressure steam in the pipe. At a certain temperature, according to the predetermined pulping time, the material passes through the root cooking tube to the last tube, and the pulp cooking process is completed.