Boost efficiency and sustainability: The power of upgrading your thickeners

Thickeners are essential for water recovery, a topic closely linked to a company’s license to operate. As society embraces circularity and waste minimization, upgrading existing infrastructure has become more pertinent. Improved thickener performance can de-bottleneck operations, enhancing upstream and downstream efficiencies, and enabling plants to maximize their existing infrastructure.

Water sustainability is a crucial ESG issue, and thickener performance plays a vital role. Upgrading thickeners can drive significant improvements in water recovery, reducing environmental impact. Modern designs also offer potential energy and flocculant savings, lowering operational carbon and supporting sustainability goals.

Upgrading older thickener designs to meet today’s standards can also lead to significant gains in safety, maintenance, and ease of operability. Improving dewatering performance can also directly impact the safety and operability of tailings management facilities, ensuring a safer environment and more efficient operations.

Modernizing your thickener: A tailored and holistic upgrade journey

When it comes to thickener modernization, there's no one-size-fits-all solution. Every site presents unique challenges, from specific operational needs to existing equipment that demands an overhaul. To navigate this complex terrain effectively, it's crucial to adopt a systematic approach to upgrading — one that aligns seamlessly with your business objectives. This entails addressing various key areas:

1. Process design criteria: Tailoring the upgrade to match the intricacies of your processes.
2. Maintainability: Ensuring the new setup is easy to maintain and troubleshoot.
3. Operability: Focusing on usability and efficiency in day-to-day operations.
4. Stockholding topics: Considering spare parts availability and standardization including commonality of parts.
5. Safety improvements: Enhancing safety protocols and measures.
6. Existing site constraints: Adapting the upgrade to fit within the site's limitations.
7. Site standards: Compliance with legislative, industry and customer specific standards.
8. Schedule and budget: Managing timelines and costs effectively.

While these considerations may seem daunting, they are essential for a successful upgrade. Adopting a holistic and systematic approach allows for a smoother transition and ensures that your thickener modernization meets all necessary criteria. In the following sections, we'll delve deeper into each aspect, providing insights and strategies for a tailored upgrade journey that aligns perfectly with your operational needs.

The value of thickener test work

Thickener test work is a highly valuable and cost-effective method for benchmarking performance across various operating scenarios. This essential step in the upgrade process helps define performance expectations and provides critical data to inform upgrade design parameters.

Data gathered during thickener testing offers valuable information on several aspects of the upgrade design to achieve the specified process targets, including:

• Raking mechanism and drive torque design requirements: Understanding these parameters ensures the upgraded thickener can handle the mechanical demands of the specified loadings after upgrade.
• Optimal feedwell solids concentration: Identifying the ideal solids concentration is crucial for effective flocculation, which is a key input for feed system upgrade design.

By conducting thorough thickener test work, plants can ensure their upgrade strategies are well-informed, leading to enhanced performance and efficiency.

A holistic approach to thickener upgrades: Beyond the basics

Looking beyond 'flange to flange' thickener scope

Achieving a successful thickener upgrade often requires a holistic approach that goes beyond the typical 'flange to flange' battery limits. By considering the entire process, including upstream factors, we can ensure a successful upgrade project that delivers optimal performance and efficiency.

Case study example

In a case study, the scope of the upgrade included a comprehensive plant hydraulics study that extended beyond the thickener feed battery limit. This study revealed a significant issue: a steep fall in feed pipework created a turbulent, high-energy launder flow stream with a velocity of approximately 5.5 m/s.

Identifying the problem

This turbulent flow caused significant froth and excess shear energy in the existing feedwell, leading to sub-optimal underflow density and poor overflow clarity.

Implementing a customized solution

To address these issues, a customized solution was implemented. A large external feed tank was designed with features aimed at substantial froth reduction and minimized wear. This approach ensured a more stable and efficient thickening process, resulting in improved underflow density and overflow clarity.

By adopting a holistic approach to thickener upgrades, we can identify and address underlying issues, leading to more effective and sustainable solutions.

Advancements in thickener feed system technology

The thickener feedwell, often referred to as the "heart of thickener performance," is a critical component that performs multiple essential functions:

• Conditioning incoming feed slurry: Achieving optimal conditions for effective flocculation.
• Controlling kinetic energy: Ensuring sufficient mixing of feed slurry with dilution liquor and reagents while maintaining a low shear environment for ideal floccule growth.
• Solids hold up and retention: Preventing short-circuiting of flocculated material and achieving controlled flow of dilution liquor.
• Even discharge: Utilizing the full area of the thickener body.

These functions must work in harmony to maximize performance and optimize flocculant consumption across various feed conditions. Over time, significant design improvements have enabled leaps forward in performance compared to earlier designs. Modern techniques, such as Computational Fluid Dynamics (CFD) modeling, in combination with real-world prototyping and validation, have played a crucial role in the technological advancements resulting in Metso’s first-class Reactorwell™ upgrade.

Boost efficiency and sustainability: The power of upgrading your thickeners

In conclusion, upgrading thickeners is a valuable step for processing plants looking to enhance performance, optimize operating costs, and meet modern sustainability and safety standards. By investing in today’s leading thickener technology and a holistic approach to the upgrade process, plants can overcome bottlenecks, improve operational efficiencies, and contribute to their broader ESG objectives.