Challenges of Pressurized Water Treatment Plants: Achieving Turbidity Below 1 NTU with Efficiency and Operational Safety

In pressurized Water Treatment Plants (WTPs), strict control of operational parameters is essential to ensure the quality of the treated water. One of the main challenges is achieving turbidity levels below 1 NTU at the filter outlet—an essential parameter for the preservation and performance of softening systems using cationic resins.

When turbidity levels remain high, even after applying conventional treatment processes, several significant impacts may occur, including:

• Early saturation of ion exchange resins;

• Reduced efficiency in removing hardness salts;

• Increased consumption of chemical inputs;

• Shortened equipment lifespan;

• Compromised quality of the final water delivered.

Limitations of Using Inorganic Coagulants Alone

In industrial applications, the isolated use of coagulants such as 18% PAC often does not ensure the desired turbidity level at the WTP outlet. Even under controlled pH and dosing conditions, the absence of a complementary flocculant can lead to limited process efficiency, resulting in treated water with turbidity levels above 10 NTU and compromising downstream stages.

To address this issue, the implementation of specific technical analyses is recommended, including:

• Detailed diagnosis of operational conditions and raw water profile;

• Execution of Jar Tests to accurately determine dosing and assess system behavior in a controlled environment;

• Study of the synergy between coagulant and flocculant;

• Development of treatment strategies tailored to the characteristics and constraints of each operation.

Technical Comparison – Jar Test with and without Anionic Flocculant

The introduction of a high-performance anionic flocculant combined with the previously used coagulant demonstrated significant results.

Observed Results:

Becker A (coagulant + flocculant):

• Formation of homogeneous flocs with higher density and defined structure;

• Superior settling performance with optimized filter retention;

• Significant reduction in residual turbidity.

Becker B (coagulant only):

• Formation of unstable microflocs with poor settling capacity;

• High recirculation of suspended solids;

• Final turbidity above the specified limit.

Final Performance:

Turbidity reduction from 10 NTU to 0.99 NTU achieved through optimized coagulation-flocculation strategy.

Technical and Consultative Approach

The proven performance highlights the need for integrated solutions that go beyond the standard application of isolated coagulants. The absence of complementary conditioning and the use of products not specifically tailored to the water profile negatively impact the system's overall efficiency.

Ecosign offers specialized technical support and customized solutions, taking into account:

• Physicochemical characteristics of the raw water;

• Operational pH range;

• Average process temperature;

• Organic and inorganic material content;

• Specific variables of each industrial plant.

Commitment to Performance and Sustainability

Ecosign’s solutions deliver consistent and sustainable results, with ongoing technical support and a focus on improving operational performance. Get in touch with our team to learn more!

Author: Matheus Battarra, Sales Manager – Water Treatment