Do Coagulants and Flocculants Really Work?

September 21, 2021
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What’s the deal with coagulants and flocculants? Do they really work? If you’re looking for an effective wastewater treatment solution, it’s important to understand all your options. Let’s learn a little more about how chemical coagulants can make your wastewater treatment process run smoother.


What is Coagulation and Flocculation?

First thing’s first: What is coagulation? What is flocculation and how do the processes work together? While they both help in the process of solid/liquid separation, they do so a bit differently.


Coagulation occurs when a liquid turns into a solid or semi-solid. Just think about what happens when milk goes sour. The pH level in the milk changes and chunks form. That’s coagulation. Coagulants are chemicals that destabilize suspended solids to encourage aggregation and sedimentation. The manipulation of electrostatic charges in solids is what causes destabilization. It is important to choose the right coagulant to enhance the sedimentation process. Different coagulants work better for specific industries, and there are both organic and inorganic options.


Flocculation is preceded by coagulation. Flocculation is when solids form larger clusters–sometimes called “flocs.” This process is jump started with the use of polymers that cause smaller solids to bind together.


Adding Coagulants and Flocculants to your Process

Once you’ve collected your wastewater slurry and screened or strained it as needed, you can add your coagulants and flocculants to begin the coagulation and flocculation process. Once the sedimentation process occurs, you’re ready to run your water through a filter press to clarify the water further. You’ll be left with very clean water.


Chemical feed systems, or dosing pumps, are designed to deliver chemicals directly into the water stream at a precise dosage. These systems can also monitor pH levels and keep bacterial growth at bay. By reducing suspended solids, chemical dosing means that your equipment won’t have to work as hard.





So, do chemical coagulants and flocculants really work? The answer is yes, but they may not be effective enough to produce the quality of water you need–especially if you’re producing large amounts of wastewater in your stone fabrication shop or in the concrete industry. However, utilizing the chemicals can smooth out your process. They should be seen as a step that will enhance your wastewater treatment process, but they should not be the only step in your treatment process.