Single-disc Refiner Zone Segmentation for Energy Reduction

Solution Overview

Problem

Single-disc high-consistency wood chip refiners have high energy consumption and low production capacity due to their conventional refining surface design, which limits their efficiency compared to double-disc refiners.

Innovation Solution

The refining surfaces of the single-disc refiner are redesigned with a feed zone followed by a treatment zone, where the treatment zone is located closer to the outer circumference, and the feed bar is arranged to extend towards the stationary refining element, decreasing in height towards the outer circumference, mimicking the refining conditions of double-disc refiners.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If conventional single-disc refiner design is used, then structure is simple, but energy consumption is high and production capacity is low

Engineering Contradiction:

Improverefiner structureVSAvoidproduction capacity

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The refining surface is segmented into distinct feed zone and treatment zone with different blade element configurations. The feed zone has blade elements optimized for material introduction while the treatment zone has blade elements optimized for refining, allowing each segment to perform its specific function efficiently without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different zones of the refining surface are given different local properties through varied blade element designs. The feed zone features blade elements with specific geometries for efficient material feeding, while the treatment zone features blade elements with different geometries optimized for refining, creating local quality variations that enhance overall performance.

Inventive Principle:

Principle #3Local quality

2Device complexity

If conventional single-disc refiner design is used, then structure is simple, but energy consumption is high

Engineering Contradiction:

Improverefiner structureVSAvoidenergy consumption

Core Design Contradiction:

Device complexityVSUse of energy by moving object

Solution Approach 1:

The refining surface is segmented into distinct feed zone and treatment zone with different blade element configurations. The feed zone has blade elements optimized for material introduction while the treatment zone has blade elements optimized for refining, allowing each segment to perform its specific function efficiently without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different zones of the refining surface are given different local properties through varied blade element designs. The feed zone features blade elements with specific geometries for efficient material feeding, while the treatment zone features blade elements with different geometries optimized for refining, creating local quality variations that enhance overall performance.

Inventive Principle:

Principle #3Local quality

3Productivity

If treatment zone is located closer to outer circumference, then refining efficiency improves, but feed zone area decreases

Engineering Contradiction:

Improverefining efficiencyVSAvoidfeed zone area

Core Design Contradiction:

ProductivityVSArea of moving object

Solution Approach 1:

The refining surface is segmented into distinct feed zone and treatment zone with different blade element configurations. The feed zone has blade elements optimized for material introduction while the treatment zone has blade elements optimized for refining, allowing each segment to perform its specific function efficiently without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The blade elements are designed with three-dimensional geometries that extend in the axial direction, allowing the feed zone and treatment zone to overlap partially in the radial dimension while maintaining distinct functional regions. This dimensional approach allows efficient use of the refining surface area.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP2960367B1Single-disc refiner

Publication Date: 2024.02.14 VALMET TECH OY

Figure 1
Figure 2~4

AI summary

A single-disc refiner (1) comprising a stationary refining element (2) and an opposed rotatable refining element (12). The stationary and rotatable refining elements each comprise at least one radially inner blade element (4, 14) providing an inner refining surface area of the refining element and at least one radially outer blade element providing an outer refining surface area of the refining element. The inner and outer refining surface areas of each refining element together provide a refining surface of the refining element, the refining surfaces comprising a feed zone (29) followed by a treatment zone (30). A transition point from the feed zone to the treatment zone is located at a radial distance of 70 - 90% from the centre of the refiner or at a radial distance of 50 - 80% from the innermost edge (25, 27) of the refining element or at a radial distance of 20 - 50% from the inner edge (34) of the outer blade element (8, 18, 33) towards the outermost edge (26, 28, 35) of the refining element.