High consistency refining is achieved through high consistency disc refiners or other high consistency refining equipment. Compared to low consistency refining, high consistency refining can significantly improve the performance of paper, such as tensile strength, tear resistance, folding resistance, burst resistance, and elongation.

High concentration beating can effectively, fully, and uniformly treat the slurry. The resulting slurry, with fiber cutting, can maintain more fiber length and strength, and has good water filtration performance.

High concentration pulping is suitable for processing thick walled fiber slurries such as masson pine and larch, and for refining the friction between short fibers such as grass fibers and hardwood pulp. This is the main difference between high concentration and low concentration.

During low concentration pulping, due to a large amount of water in front of the fibers, the distance between the fibers increases, and water plays a role in changing the properties of the fibers. So low consistency pulping requires a small gap between the blades, even reaching the thickness of a single fiber, in order for the fibers to be subjected to pulping. However, due to the processing and installation of pulping equipment, or uneven wear and tear of the blades during use, the gap size between the blades can be inconsistent. At places where the gap is too small, the fibers will be subjected to strong crushing and cutting; In areas with excessive gaps, the fibers are not subjected to necessary beating treatment. Therefore, the uniformity of low concentration is poor, and the fibers are more cut off.

Due to the high concentration of the slurry, there is a large gap between the plates and mills. The purpose of refining is not to rely on the direct action of the grinding plates on the fibers, but to rely on the mutual friction, compression, and rubbing of the high concentration slurry between the grinding plates, causing the fibers to be subjected to refining. Therefore, a large amount of frictional heat is generated at the same time, which softens the fibers and is beneficial for the detachment of the slurry.

So compared to low concentration refining, high concentration refining has a longer average fiber length and fewer short fibers and small fiber fragments. High concentration beating, slow increase in beating degree, and good drainage performance of the slurry.

There are also significant differences in the morphology of fibers in high concentration pulping. The fibers in high concentration pulping have obvious brooming and longitudinal splitting, and the fibers are soft and full of swelling properties. The fibers are mostly twisted and have good shrinkage performance, which can greatly improve the strength, toughness, and burst resistance of paper. It is of great significance for producing paper types that require high toughness, such as cement bag paper, cigarette paper, and high-speed rotary printing paper.