Wet-Processing Mill and Downstream Classifier for High-Dry-Matter Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mills and classifiers for material processing are limited by the need for integrated separation devices, which restrict their functionality and efficiency, particularly when dealing with high dry matter content materials.
Innovation Solution
A mill designed without a separation device, combined with a downstream classifier, allows for separate processing stages to handle high dry matter content materials, utilizing classifiers like drum sieves, fan nozzles, and cyclones to achieve efficient separation and defibration, with optional use of a kneader for thickening and high shear forces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a mill is equipped with an integrated separating device (classifier), then separation can be performed within the mill, but the mill cannot be used purely as a grinding or kneading unit and the device complexity increases
Solution Approach 1:
The system is divided into separate functional units: a mill dedicated to grinding/kneading and a separate classifier for separation. The mill processes material without integrated separation components, while the classifier handles classification downstream. This segmentation allows each device to be optimized for its specific function, resolving the contradiction between processing efficiency and structural complexity.
Solution Approach 2:
The separating device (classifier) is extracted from the mill structure and positioned as a separate downstream component. The mill is designed without integrated classification functionality, allowing it to operate purely as a grinding or kneading unit. This extraction eliminates the complexity of integrating separation mechanisms while maintaining effective material processing through the separate classifier.
2Productivity
If material is processed with high dry matter content, then defibration performance increases, but blockages occur in lines and cyclones
Solution Approach 1:
A suspender is introduced before the mill to pre-dilute the material with water, creating a slurry that flows freely through the system. This preliminary action prevents blockages in feed lines and cyclones by ensuring adequate liquid content during transport, while allowing the mill to process material at high effective dry matter content for optimal defibration performance.
Solution Approach 2:
The system dynamically adjusts material consistency parameters: the suspender increases water content to prevent blockages during transport, while the mill operates with high dry matter content material for superior defibration. The classifier then processes material at controlled dry matter levels (15-30%), optimizing separation efficiency without causing blockages.
3Speed
If a baffle plate immediately rebounds material, then separation occurs quickly, but materials do not detach properly at the edge of the baffle plate
Solution Approach 1:
The baffle plate incorporates curved surfaces instead of flat surfaces. The convex side faces the material inlet and the concave side faces the separation point. This curvature causes material to slide along the plate surface rather than immediately rebound, allowing proper detachment at the edge while maintaining efficient separation. The curved geometry optimizes both separation speed and precision by controlling material flow dynamics.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables effective separation and defibration of materials with high dry matter content, minimizing blockages and maximizing production efficiency by allowing multiple processing cycles and high shear forces in the kneader, while reducing fiber damage and waste.
Implementation Method 1
A suspension is fed to a cyclone, from which the suspension overflows together with the light materials. The heavy materials are separated in the cyclone or settle in a conical channel at the bottom of the classifier.
Implementation Method 2
Separation of material in a liquid can also be achieved with a classifier equipped with a fan nozzle. A fan nozzle allows materials in the liquid to be separated by fanning out the liquid flow.
Implementation Method 3
The high dry matter content in the kneader creates very high shear forces that grind the material and separate different materials.
Implementation Method 4
the material exiting the material inlet at a speed so high that it hits the baffle plate and bounces off, or is initially guided along it until it detaches from the plate at the edge of the baffle plate. This results in different materials bouncing off or detaching from the plate with different momentum
Data Source
Figure 1~2
Figure 3~4
Figure 5~7
AI summary
The invention relates to a method for the wet processing of material using a mill, which can also be designed as a kneader, and a downstream classifier. This classifier can also be arranged outside the mill. Furthermore, various process variants and devices are described.