Batch Defiberizing Drum with Adjustable Inclination

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Solution Overview

Problem

Existing defiberizing technologies, such as pulpers with rotating rotors, are inefficient for processing smaller amounts of fibrous materials like recovered paper and board due to high energy consumption and fiber breakage, and transportation costs for recycling these materials are not profitable, necessitating a cost-effective and low-energy solution for batch processing.

Innovation Solution

A batch-type defiberizing drum arrangement that operates in a horizontal position with adjustable inclination and rotation direction between stages, allowing for flexible defiberizing and screening processes, reducing energy consumption and fiber loss, and enabling efficient processing of smaller material quantities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a pulper with a fast rotating rotor is used for defiberizing, then intensive cutting forces are applied to disintegrate fiber bonds, but energy consumption increases and fibers are broken

Engineering Contradiction:
Improvefiber bond disintegrationVSAvoidenergy consumption
Core Design Contradiction:
StrengthVSUse of energy by moving object

Solution Approach 1:

The patent replaces the high-speed rotating rotor mechanism with a low-speed rotating drum that uses lifting planes to elevate and drop material. This substitutes intense mechanical cutting forces with gravitational impact and friction-based defiberizing, significantly reducing energy consumption while maintaining fiber bond disintegration effectiveness

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention changes the operational parameters from high-speed rotation (intensive cutting forces) to low-speed rotation with controlled material elevation and dropping. This parameter change transforms the defiberizing mechanism from mechanical shearing to gravitational impact, reducing energy consumption while achieving comparable fiber separation

Inventive Principle:
Principle #35Parameter changes

2Strength

If a pulper with a fast rotating rotor is used for defiberizing, then fiber bonds are disintegrated, but fiber losses increase

Engineering Contradiction:
Improvefiber bond disintegrationVSAvoidfiber loss
Core Design Contradiction:
StrengthVSLoss of substance

Solution Approach 1:

By replacing the high-speed rotor with a low-speed drum system that uses lifting planes and gravitational dropping, the invention avoids the intense mechanical shearing that causes fiber breakage. The gentler defiberizing mechanism maintains fiber integrity while still achieving bond disintegration

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The lifting planes are designed as replaceable wear components that can be easily replaced when worn, allowing the main drum structure to remain intact and preserving the overall system's fiber-processing capability over time

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Productivity

If a continuous defiberizing drum is used, then large amounts of material can be processed, but the system is not suitable for smaller material quantities

Engineering Contradiction:
Improvematerial processing capacityVSAvoidsuitability for batch processing
Core Design Contradiction:
ProductivityVSAdaptability or versatility

Solution Approach 1:

The drum's inclination angle is made dynamically adjustable, allowing the system to switch between configurations optimized for batch processing (smaller quantities) and continuous processing (larger quantities). This dynamic adaptability enables the same equipment to handle varying material volumes efficiently

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The drum design incorporates multiple functional zones (defiberizing portion with lifting planes and screening portion with holes) that can operate in different modes. The system can function as either a batch-type or continuous-type defiberizing apparatus, providing universal applicability for different processing requirements

Inventive Principle:
Principle #6Universality (Multi-functionality)

4Ease of manufacture

If the drum is operated in batch mode, then smaller material quantities can be processed cost-efficiently, but the process requires multiple stages with direction changes

Engineering Contradiction:
Improvecost-efficiency for small batchesVSAvoidprocess stage complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The invention combines defiberizing and screening functions into a single integrated drum, eliminating the need for separate drums or complex multi-stage systems. The drum performs both functions sequentially as material moves through different zones, reducing overall system complexity while maintaining batch processing efficiency

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The drum interior is segmented into distinct functional portions: a defiberizing portion with lifting planes and a screening portion with holes. This segmentation allows each zone to perform its specific function efficiently while being part of a unified, manageable system

Inventive Principle:
Principle #1Segmentation

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

The batch-type process allows for adjustable retention times and energy-efficient defiberizing and screening, minimizing fiber breakage and energy use, while maintaining coarse impurities and reducing operational costs compared to continuous pulper systems.

Implementation Method 1

longitudinal internal lifting planes or lifting blades, which during rotation of the drum continuously lift material being treated from the lowest portion of the drum to a higher located portion, from where it is casted against the housing of the drum and exposed to refining and cutting forces

Methodology Applied
Scientific EffectGravity: Gravitation

Implementation Method 2

the rotor focuses intensive cutting forces to the material being treated

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 3

material being treated, from where it is casted against the housing of the drum and exposed to refining and cutting forces that disintegrate fiber bonds

Methodology Applied
Scientific EffectImpact force: Impact Force

Data Source

PatentEP3307939B1Method and arrangement for defiberizing fibrous material and use of a defiberizing drum
Publication Date: 2019.02.27 ANDRITZ OY
  • EP3307939B1 patent drawingFigure 1
  • EP3307939B1 patent drawingFigure 2
  • EP3307939B1 patent drawingFigure 3

AI summary

The present invention relates to a method for defiberizing fibrous material, especially recovered paper or recovered board, in a rotary defiberizing drum having a material defiberizing portion and a screening portion. The method comprises following steps: a) a batch of fibrous material and liquid is fed into the defiberizing drum, b) material is defiberized in the defiberizing portion of the defiberizing drum, b) the defiberized material batch is transferred to the screening portion of the defiberizing drum, c) the defiberized material batch is treated in the screening portion, wherein accepted fiber material is separated through the screening surface into accept, and d) the reject material is discharged from the defiberizing drum, and the direction of rotation or the inclination of the defiberizing drum, or both, is changed at least between method steps b) and e). The invention also relates to a defiberizing drum arrangement and use.