This week, GN Separation successfully completed the assembly of four GNLW224 decanter centrifuges, along with their matching polymer dosing units, at its manufacturing plant. These pieces of equipment are slated to undergo a final inspection and acceptance test conducted by an overseas client next week.

Product Overview

The GNLW224 is the smallest-capacity model in GN Separation's lineup of decanter centrifuges specifically tailored for wastewater treatment applications. It is ingeniously engineered to deliver dependable performance even in compact spaces. Operating at a maximum rotational speed of 5,000 RPM, this centrifuge can efficiently separate solid and liquid phases from a wide range of industrial and municipal wastewater streams.

Each centrifuge comes equipped with a 3-variable-frequency drive (VFD) control cabinet. This advanced feature empowers operators to fine-tune crucial parameters, such as bowl speed, differential speed, and feed pump flow rate. By doing so, they can optimize processing conditions according to the unique characteristics of the materials being treated and specific operational needs.

Integrated Polymer Dosing Units for Enhanced Efficiency

To further boost overall treatment efficiency, the centrifuges are paired with GN Separation's polymer dosing units. These units are designed to precisely introduce flocculating agents into the wastewater stream. The addition of these agents through chemical conditioning promotes particle aggregation, which in turn makes the separation of suspended solids during centrifugation more effective. The synchronized operation of the centrifuges and dosing systems enables end-users to achieve higher solid-liquid separation rates and produce clearer effluent. This not only reduces the workload for downstream processing but also minimizes the environmental impact.

Compact Design and Robust Construction

The GNLW224 boasts a compact footprint, allowing it to be seamlessly integrated into existing plant layouts without the need for extensive modifications. This is a significant advantage for facilities looking to upgrade outdated equipment or expand their capacity within limited space. Moreover, its robust construction, featuring corrosion-resistant materials and wear-resistant components, ensures long-lasting durability. It can withstand demanding operational conditions, such as high-temperature environments or those involving abrasive sludge.

Upcoming Client Inspection Details

The upcoming client inspection will involve a comprehensive testing process for the assembled units. This includes verifying rotational speeds, water test flow rates, vibration levels, and the rise in main bearing temperature, among other parameters. GN Separation's technical team will work closely with the client's engineers during the inspection. They will demonstrate the system's capabilities and address any specific concerns the client may have regarding the integration of the new equipment with their existing infrastructure.

Market Position and Future Prospects

In recent years, there has been a steady increase in demand for compact and energy-efficient wastewater treatment technologies. This trend is driven by stricter environmental regulations and growing industrialization in emerging markets. GN Separation's decanter centrifuge is well-positioned to take advantage of this market opportunity. It offers a cost-effective alternative to larger, more complex systems without sacrificing performance. With production lines now gearing up to meet the expected demand, GN Separation is solidifying its position as a competitive player in the global wastewater treatment equipment sector.

Recently, GN Separation successfully delivered two sets of 240 m³/h trenchless mud treatment systems to a customer in Australia. Each system is designed to efficiently process drilling and trenchless construction mud, ensuring effective recycling and reuse.

Each System Includes:

• One 11.5 m mud tank

• Two double-deck vibrating screens

• Two desander cyclones

• Ten 5-inch desilter cyclones

• Three sand pumps

• One mixing hopper

• One agitator

These systems are designed for trenchless drilling and horizontal directional drilling (HDD) projects, where efficient solids control and fluid recovery are critical for cost reduction and environmental compliance.

Double-Deck Vibrating Screens — The Core Equipment

Each mud treatment system is equipped with two double-deck vibrating screens, which serve as the key equipment for primary solids separation. The vibrating screens remove large solids from the drilling mud, ensuring that the downstream desander and desilter units receive mud with lower solids content, thus improving the overall separation performance.

Technical Features

The double-deck vibrating screen shares design concepts with GN’s high-performance vibrating screen range, as described on GN Solids Australia’s website. The main technical features include:

• Double-Deck Structure:
  Two screening decks are driven by a single vibration source, providing larger screening area and enabling two-stage separation or finer solids removal within limited space.

• Linear Vibration Motion:
  The screen box operates in a linear motion pattern, ensuring efficient material conveyance and effective solids discharge. This motion type is ideal for treating slurry and liquid-solid mixtures.

• High-Quality Polyurethane (PU) Screens:
  PU screens offer excellent wear resistance, elasticity, and self-cleaning properties. The high open area (typically 28–45%) ensures efficient screening while minimizing blinding.

• Compact and Space-Saving Design:
  The double-deck design allows higher processing capacity within a smaller footprint — an important advantage at job sites with limited space.

• Dual-Motor Self-Synchronization Drive:
  Two vibration motors work in self-synchronization to ensure stable operation and uniform vibration, reducing maintenance and energy consumption.

• Anti-Corrosion and Wear-Resistant Surface Treatment:
  The screen box is treated with sandblasting, heavy-duty anti-corrosion coating, and a polyurea wear layer on surfaces exposed to mud, ensuring long service life in harsh field environments.

Application Advantages in This Project

The inclusion of double-deck vibrating screens in this system offers several operational benefits:

• Higher Primary Solids Removal Efficiency:
  Coarse solids are quickly separated, reducing the solids loading on the desander and desilter units, and improving the overall treatment performance.

• Reduced Footprint and Structural Height:
  Compared with two single-layer screens, the double-deck design saves space while maintaining large screening capacity — ideal for compact trenchless job sites.

• Stable and Continuous Operation:
  Linear motion and flexible PU screens prevent blinding and ensure consistent performance, minimizing downtime and maintenance needs.

• Energy Efficiency and Easy Maintenance:
  The simple structure, synchronized drive, and long-lasting screens help reduce operational and maintenance costs.

• Customizable Design:
  The vibrating screen can be customized based on the site’s mud properties (solid content, particle size distribution, viscosity, etc.) by adjusting screen mesh size, vibration amplitude, and feeding mechanism.

Technical Reference

While this project uses double-deck vibrating screens, their design principles align with GN’s multi-deck (2–5 layers) vibrating screens, as shown on the GN Separation official website:

• Screen angle: 17.5°

• Vibration frequency: ~25 Hz

• Double amplitude: 1–2 mm

• Mesh size range: 0.045–2 mm

• Material: Polyurethane or stainless steel mesh

These parameters ensure high efficiency, precision, and stability in fine particle separation.

Operation and Maintenance Recommendations

To achieve the best field performance, GN recommends:

• Even Feeding: Install a buffer box or flow divider at the feed inlet to distribute slurry evenly across both decks.

• Regular Cleaning: For sticky or high-sand-content mud, equip the screen with a spray cleaning system to prevent clogging.

• Screen Inspection: Periodically check screen tension, mesh integrity, and fastening bolts.

• Monitor Vibration System: Keep track of motor temperature, vibration frequency, and amplitude to prevent imbalance.

• Easy Access Maintenance: Design the platform for convenient screen replacement and motor servicing.

Project Highlights & Customer Benefits

• High Processing Capacity: 240 m³/h throughput per system meets demanding trenchless operations.

• Compact Modular Design: Facilitates transportation, installation, and integration with existing job site systems.

• Improved Mud Recycling Efficiency: Ensures better fluid recovery and cleaner mud for reuse, reducing waste disposal costs.

• Reliable and Durable: Built with robust materials and proven GN manufacturing standards.

• Localized Support: GN’s technical and after-sales teams provide professional guidance for installation and commissioning in Australia.

Summary

The successful delivery of these two systems demonstrates GN Separation’s strong capability in providing efficient and reliable trenchless mud treatment solutions. With advanced design, durable equipment, and proven field performance, GN Separation continues to support clients in Australia and worldwide in achieving cleaner, more sustainable construction operations.

1. Background – Why screening matters in iron-ore mining

In the domestic (within-country) iron-ore mining context, efficient separation and classification of fine particles is increasingly important. After primary crushing and grinding, a high fraction of fine material (e.g., sub-2 mm) often needs to be removed or classified before subsequent processes (e.g., beneficiation, pelletising, tailings disposal). Using an appropriate vibrating screen for fine material helps to: