Refining Arrangement Return Flow Channels
Solution Overview
Problem
Existing refining technologies for aqueous suspended fibrous materials, such as cellulose fibers, face inefficiencies in achieving uniform fiber properties and excessive wear of grinding surfaces, necessitating improved methods for fiber treatment and surface utilization.
Innovation Solution
The implementation of return flow channels connecting the outlet to the inlet under at least one grinding surface allows for recirculation of the pulp suspension, enhancing homogeneous refining and compensating for fiber shortages, while flow barriers and adjustable valves control pressure and flow, preventing uneven wear and short-circuiting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If grinding surfaces are used for fiber treatment, then fiber properties are improved, but uneven wear on the refining surface occurs
Solution Approach 1:
The invention extracts the return flow channels from the direct grinding path, positioning them underneath the grinding surface. This separation allows the recirculation of fibrous suspension without direct contact between the returned material and the grinding edges, preventing uneven wear while maintaining fiber treatment effectiveness
Solution Approach 2:
The invention recovers fibrous suspension from the outlet and returns it to the inlet through return flow channels. This recycling process ensures complete passage of the suspension through the refining gap multiple times, improving fiber treatment uniformity and compensating for fiber shortages without causing wear on the grinding surfaces
2Stability of the object's composition
If recirculation of pulp suspension is implemented, then homogeneous refining is improved, but pressure build-up occurs
Solution Approach 1:
The invention modifies the flow cross-section parameters of the return flow channels by introducing constrictions. These constrictions are dimensioned to regulate the amount of pulp suspension flowing back, thereby controlling pressure build-up while maintaining homogeneous refining through appropriate recirculation rates
Solution Approach 2:
The invention introduces adjustable valves in the return flow channels to dynamically control the throughput of recirculating suspension. This allows active adjustment of pressure conditions and flow rates to optimize both refining uniformity and pressure management according to specific operational requirements
3Productivity
If return flow channels are added for recirculation, then refining efficiency is improved, but device complexity increases
Solution Approach 1:
The invention merges the return flow channels with the existing refining structure by positioning them underneath the grinding surface and integrating them with the inlet and outlet. This consolidation achieves recirculation functionality without adding separate external systems, thereby improving refining efficiency while minimizing increases in device complexity
Solution Approach 2:
The return flow channels serve multiple functions: they recirculate pulp suspension for homogeneous refining, compensate for fiber shortages, and can be equipped with valves and constrictions for pressure control. This multi-functionality achieves improved refining efficiency without requiring multiple separate devices or systems
Data Source
Figure 1~3
Figure 4~6
AI summary
The invention relates to a refining arrangement for refining aqueously suspended pulp between two refining surfaces, which form a refining gap (1) and rotate relative to each other and are formed by refining strips (2) and grooves (3) extending therebetween, wherein the refining strips (2) extend, at least together with a directional component, radially with respect to the rotation axis (4), and the pulp suspension (5) flows through the refining gap (1) from a radially inner, circular inlet (6) to a radially outer, circular outlet (7). Efficient refining is achieved according to the invention in that a plurality of return flow channels (8) connecting the outlet (7) to the inlet (6) are arranged under at least one refining surface.