Plant operators can improve coagulation and flocculation applications to reduce water turbidity and increase purity.
by Greg Kriebel
February 24, 2017

Recognizing the needs in this critical area of municipal water treatment, a manufacturer of liquid and dry polymer preparation systems offers a patented liquid and dry polymer blending system. Both offer high-energy, non-mechanical liquid-polymer activation and blending technology designed to effectively activate all types of liquid polymers. The technology produces more than six times the mixing energy per unit volume than some others.

Patented TechnologyFigure 1. Patented technology produces more than six times the polymer mixing energy per unit volume than comparable mechanical polymer mixers.

The three stages of operation are:

  • Stage 1: Pressure drop across a specially designed variable-orifice water-control valve produces a high-velocity water jet, which travels at approximately 70 feet per second. The water jet is aimed directly at, and impinges on, the polymer as it enters the mixing chamber. At this point, the polymer coils up and is not susceptible to damage.
  • Stage 2: In the concentric mixing chambers, the newly blended polymer recirculates multiple times for additional exposure to non-damaging turbulence, completing the blending process. The recirculation ensures that the polymer solution is present directly after the point of injection for an ideal activation and blending environment.
  • Stage 3: The mixing energy then naturally diminishes in the concentric chambers, while the optimized flow path ensures optimum polymer performance by preventing the polymer from causing a disruption to the three-stage activation and blending process.

The three-stage method of operation ensures the patented system delivers high mixing energy without the use of mechanical impellers, which can cause polymer damage and gelling. Polymers that do not gel or get damaged maximize the treatment plant’s polymer investment by reducing actual polymer use. Additionally, the non-mechanical mixing chamber delivers a high degree of reliability. Also, the system’s injection-check valve has been designed with easy disassembly and inspection in mind.

Pneumatic Conveyance SystemImage 3. By using a blower-induced pneumatic conveyance system to transfer the polymer from the feeder to the wetting head, the patented system is able to reduce mixing and hydration times, deliver higher polymer performance and lower chemical costs.

The technology is ideal for water-treatment applications because it utilizes a negative-pressure, blower-induced conveyance system to transport and disperse the dry polymer prior to the wetting process. Dispersing dry polymer prior to it coming into contact with the water or wastewater ensures effective polymer-particle wetting. The result is reduced mixing and hydration times, higher polymer performance, lower chemical costs and fewer moving parts, which results in increased reliability and reduced maintenance concerns.

Other benefits include separation of polymer prior to wetting, which prevents polymer buildup at the volumetric feeder and plugging/clogging of the conveyance system. There are multiple hopper configurations. Hoppers have been designed for loading without the need for stairs or platforms, increasing operator safety, along with cleaner operation and a reduced chance of spills. And six standard control panels provide the flexibility to choose the features that best meet the operation’s requirements.

Water treatment systems are only truly successful if they can consistently, efficiently and effectively perform as intended. Helping ensure the reliable performance of water treatment operations are the preparation systems that introduce the polymers that protect the coagulation and flocculation processes that are so crucial in municipal water-treatment systems.

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