Centri-Cleaners for Low Consistency Pulp: Improve Pulp Cleanliness, Reduce Fiber Loss and Enhance Paper Quality

What Are Centri-Cleaners for Low Consistency Pulp?

Centri-Cleaners for Low Consistency Pulp, also known as LC Cleaners (Low Consistency Cleaners), are one of the most important cleaning systems used in modern pulp and paper mills.

Based on the hydrocyclone separation principle, LC cleaners operate at a pulp consistency typically ranging from 0.4% to 1.2%. By utilizing centrifugal force, the system efficiently separates contaminants from valuable fibers, producing cleaner pulp while minimizing fiber loss.

These contaminants may include:

• Sand and grit
• Small stones and dust particles
• Ink particles
• Hot melt adhesives
• Plastic particles
• Foam
• Sticky contaminants
• Debris and lightweight impurities
• Fiber bundles

By removing these contaminants, paper mills can significantly improve pulp cleanliness, enhance final paper quality, reduce equipment wear, and optimize production efficiency.

How Does a Low Consistency Centri-Cleaner Work?

The operating principle of a low consistency cleaner is based on centrifugal separation.

The pulp slurry enters the cleaner tangentially under a certain pressure, typically at a consistency of 0.4% to 1.2%.

Inside the conical body, the pulp rotates downward at high speed, creating a powerful vortex.

Heavy contaminants, such as sand, stones, metal particles and dense debris, are forced toward the outer wall of the cone due to centrifugal force. These contaminants move downward and are continuously discharged through the reject outlet at the bottom.

At the same time, the cleaned accept pulp moves toward the inner vortex and rises upward before being discharged from the top outlet into the accept pipeline.

A unique dilution and backwashing water system installed at the bottom helps recover usable fibers carried by the reject stream. This significantly reduces fiber loss while maintaining high cleaning efficiency.

The entire process operates continuously and efficiently, ensuring stable pulp quality throughout the production line.

What Contaminants Can LC Cleaners Remove?

A properly designed LC cleaning system can efficiently remove a wide range of contaminants, including:

Heavy Contaminants

• Sand
• Grit
• Small stones
• Metal particles
• Glass fragments

Lightweight Contaminants

• Foam
• Plastic particles
• Hot melt adhesives
• Sticky contaminants

Fine Impurities

• Ink particles
• Dust
• Small debris
• Fiber bundles

The cleaner system can be customized according to different pulp sources, including OCC, mixed waste paper, deinked pulp, virgin pulp, and tissue production lines.

Key Advantages of Yunda Low Consistency Centri-Cleaners

1. High Cleaning Efficiency

The optimized internal flow structure and extended cone design significantly improve contaminant removal performance.

The system effectively removes both heavy and lightweight impurities while maintaining stable pulp quality.

2. Reduced Fiber Loss

The bottom backwashing water design recovers valuable fibers from the reject stream.

This design minimizes fiber loss and improves raw material utilization.

3. Superior Wear Resistance and Long Service Life

The lower cone section adopts a ceramic-lined structure that offers excellent abrasion resistance.

Compared with conventional materials, ceramic components significantly extend equipment service life and reduce maintenance costs.

4. Flexible Multi-Stage Cleaning Configuration

Modern paper mills often utilize multi-stage LC cleaning systems.

Different cleaning stages can be combined according to process requirements to maximize cleaning efficiency while minimizing fiber losses.

This flexible design can be applied in:

• OCC pulping systems
• Tissue paper production lines
• Packaging paper production
• Deinking systems
• Fine paper production lines

Typical Applications in Paper Mills

Low consistency centri-cleaners are widely used in various process sections, including:

• Primary LC cleaning systems
• Last stage LC cleaning systems
• Recycled fiber processing lines
• Tissue paper stock preparation systems
• Packaging paper stock preparation systems
• Deinking pulp systems

Proper cleaner configuration helps improve the overall performance of the stock preparation process.

Technical Specifications

Model	System Position	Capacity	Inlet Consistency	Inlet Pressure
SC400	Last Stage LC Cleaning	400 L/min per unit	<1.2%	0.2-0.3 MPa
SC450	LC Cleaning	450 L/min per unit	<2.0%	0.25-0.35 MPa
SC600	Last Stage LC Cleaning	600 L/min per unit	<1.2%	0.2-0.3 MPa
SC1000	Last Stage LC Cleaning	1000 L/min per unit	<1.5%	0.2-0.3 MPa

Additional parameters:

• Pressure difference: 0.13-0.15 MPa
• Reject discharge mode: Closed and continuous operation

Why Are Multi-Stage LC Cleaning Systems Becoming More Important?

As paper mills demand higher paper quality and lower production costs, multi-stage cleaning systems have become increasingly important.

Compared with single-stage cleaning, multi-stage systems offer:

• Higher contaminant removal efficiency
• Lower fiber loss
• Better pulp cleanliness
• Improved final paper quality
• Reduced energy consumption
• Greater operational stability

By selecting the appropriate cleaner configuration, paper mills can achieve both quality improvement and cost optimization.

Choose the Right Centri-Cleaners for Your Pulping System

Selecting the proper Centri-Cleaners for Low Consistency Pulp depends on several factors:

• Pulp type
• Production capacity
• Contaminant characteristics
• Required paper quality
• Existing process layout

An optimized LC cleaning system not only removes contaminants efficiently but also protects downstream equipment, reduces fiber loss, and enhances overall mill performance.

As one of the key components in modern stock preparation systems, high-performance LC cleaners continue to play a vital role in improving paper production efficiency and product quality.