fisheyes

Fisheyes: A Common Problem in Water Treatment

In the world of water treatment, the term "fisheyes" might sound whimsical, but it actually refers to a frustrating and potentially problematic condition. It describes the formation of small, round clumps of undissolved polymer that resemble the eyes of a fish. These fisheyes arise when dry polymer powder is improperly mixed with water, leading to a range of issues that can impact the effectiveness of treatment processes.

Understanding the Formation of Fisheyes

Dry polymer powders are essential components in various water treatment processes, including coagulation, flocculation, and dewatering. They work by attracting and binding suspended particles in water, facilitating their removal. However, these polymers need to be properly dispersed in water to work effectively.

When dry polymer is added to water, it should dissolve and disperse evenly. However, improper mixing can lead to the formation of fisheyes. These clumps are essentially undissolved polymer particles, which are surrounded by a thin layer of dissolved polymer. This layer acts as a barrier, preventing the water from penetrating the clump and fully dissolving the polymer.

Why Fisheyes are a Problem

Fisheyes present a number of challenges in water treatment:

• Reduced Efficiency: Undissolved polymer particles are unable to participate in the binding and removal of suspended solids. This leads to reduced treatment efficiency and can result in poorer water quality.
• Clogging and Blockages: Fisheyes can clog pipes and filters, leading to costly maintenance and downtime.
• Uneven Treatment: The presence of fisheyes can create areas of uneven treatment within the water system, making it difficult to ensure consistent results.

Preventing Fisheye Formation

Preventing fisheye formation is essential for successful water treatment. Here are some key strategies:

• Proper Mixing: The most important step is to use the right mixing equipment and techniques to ensure thorough dispersion of the polymer. High-shear mixers, such as static mixers or in-line mixers, are often preferred.
• Water Quality: The quality of the water used to dissolve the polymer can also play a role. Ensure the water is clean and free of contaminants that could interfere with the dissolution process.
• Polymer Selection: Choosing the appropriate type of polymer for the specific application can also reduce the risk of fisheye formation. Some polymers are more prone to forming fisheyes than others.

Conclusion

Fisheyes are a common problem in water treatment that can significantly impact treatment efficiency and overall system performance. By understanding the factors that contribute to their formation and adopting preventative measures, water treatment professionals can minimize this issue and ensure optimal treatment results. Remember, a little attention to detail in the mixing process can go a long way in preventing the formation of these troublesome "fisheyes."