Fine Sorting Pre-Processing Device for Fiber Recovery
Solution Overview
Problem
Existing methods for recovering fiber from screening reject in the paper recycling process result in low fiber yield due to damage from disaggregating machines and re-aggregation of sticky foreign materials, which also lowers paper quality.
Innovation Solution
A method involving a fine sorting pre-processing device that generates heat through friction to soften sticky foreign materials, allowing for their detachment from fibers and subsequent granulation and balling, thereby separating fibers from sticky materials without damaging them.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a disaggregating machine is used to finely shred sticky foreign material, then the sticky foreign material can prevent papermaking machine staining and maintain paper quality, but the fiber is damaged and cut by the cutting effects of the disaggregating machine
Solution Approach 1:
The patent replaces the mechanical cutting action of a disaggregating machine with a thermal softening approach. By heating the sticky foreign material to 90°C or higher, the material softens and becomes expandable and contractable, allowing it to be detached from fibers without mechanical cutting. This substitution of thermal processing for mechanical processing resolves the contradiction by maintaining paper quality through effective sticky material removal while preserving fiber integrity.
Solution Approach 2:
The patent changes the physical state parameter of the sticky foreign material by applying heat to raise its temperature to 90°C or higher. This parameter change transforms the material from a rigid, cutting-resistant state to a softened, pliable state that can be easily detached from fibers through friction-based kneading rather than mechanical cutting, thus resolving the fiber damage issue.
2Reliability
If the size of the slits of the screen is set to a smaller one to remove sticky foreign material, then the sticky foreign material can be removed as screening reject, but fiber adheres to the sticky foreign material and is discarded together with the screening reject, reducing fiber yield
Solution Approach 1:
The patent applies preliminary thermal softening to the sticky foreign material before the actual separation process. By heating the material to 90°C or higher and performing friction-based kneading, the sticky material is softened and detached from fibers in advance. This preliminary action ensures that when the screen separation occurs, the fiber and sticky material are already separated, allowing small slit screens to effectively remove sticky material while preserving fiber yield.
Solution Approach 2:
The patent changes the physical state of the sticky foreign material through thermal heating to 90°C or higher, transforming it from a adherent, fiber-bonding state to a softened, detachable state. This parameter change enables effective separation at small slit screens by eliminating the adhesive bonding that causes fiber loss, thus resolving the contradiction between paper quality and fiber yield.
3Productivity
If the sticky foreign material is finely shredded by a disaggregating machine, then it can be processed further, but the sticky foreign material aggregates again due to the heat of the dryer and becomes tangible
Solution Approach 1:
The patent performs thermal softening and friction-based kneading as a preliminary action before the drying process. By heating the sticky foreign material to 90°C or higher and performing mechanical kneading to detach it from fibers, the material is processed in a controlled manner before drying. This preliminary action prevents re-aggregation during drying because the material has already been separated from fibers and its structure has been altered by the heat and mechanical action.
Solution Approach 2:
The patent maintains continuous thermal and mechanical action on the sticky foreign material throughout the process. Instead of allowing the material to cool and aggregate during drying, the system continuously applies heat (90°C or higher) and mechanical kneading to keep the material in a softened, detached state. This continuous useful action prevents re-aggregation and maintains processing efficiency.
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
This method effectively increases the yield of recovered fibers by preventing damage and re-aggregation, while maintaining paper quality by removing sticky foreign materials efficiently.
Implementation Method 1
heat of 90° C. or higher is generated through friction between fibers and sticky foreign material
Implementation Method 2
such an environment that heat of 90° C. or higher is generated through friction between fibers and sticky foreign material is softened and becomes expandable and contractable
Data Source
AI summary
Waste paper contains sticky foreign material, and the recovery and sending of this sticky foreign material to a paper-making process together with fiber is liable to lead not only to the sticky foreign material sticking to and contaminating the paper making machine or dryer but also paper peeling and tearing, causing a decline in paper quality. This method for recovering fiber form a screening reject is characterized by comprising the steps of: sending a screening reject coming out from a coarse sorting process to a fine sorting pre-processing process such that the screening reject is impacted against rotating blades 8 or stationary blades 11 in the interior of a cylinder body 2 and detachment of the fibers from the sticky foreign material by the sticky foreign material being kneaded and granulation and balling-up of the detached sticky foreign material are promoted, taking advantage of the sticky foreign material becoming extendable and shrinkable due to softening in an environment in which heat is generated from friction between fibers; and then sending the result to the fine sorting process so that the fiber is recovered with the balled-up sticky foreign material being separated as a screening reject via the fine sorting process.