Industrial wastewater from most industries do not meet the effluent standard without dosing It is a necessity for the wastewater to be removed from all toxic components before discharging it.
Dosing of chemicals can have several reasons:
- Nutrients removing (P) by precipitation
- Heavy metals removing (sulfurous, hydroxides etc)
- Combined process (disinfection ,Fenton, oxidation)
- pH adjusting
The chemicals are then in a bond with the solids or elements which are unwanted in the effluent. In the most applications the solids have then to be removed with the chemicals.
To decide which treatment technology should be used in a project, our specialists from ClearFox look at how big the particles in the wastewater are. For solids that are visible to the naked-eye we use techniques such as DAF (Dissolved Air Flotation) or Lamella Clarifier.
For smaller particles which are called suspended solids (size < 1 µm) or colloids, all these methods are not working. For this we need Physico-Chemical pre-treatment.
How it works:
Basically we add chemicals such as coagulants and flocculants which makes the small particles remain in an indefinitely stable form resulting in them forming into bigger particles that can be treated with our normal methods.
The three stages of Chemical wastewater treatment:
Stage 1 (Coagulation):
As previously said, coagulants are added to the wastewater, making them become little flocks by changing the physical state of the colloids. Typical chemicals for this treatment stage are iron polychloride, aluminum sulfate, ferric chloride and ferric sulfate.
Stage 2 (Flocculation):
In this stage we make the newly formed flocks group up together to become even more bigger. We archieve this by applying so called “floculants” to the wastewater. They can be distinguished by their nature (mineral or organic), their origin (synthetic or natural) or their electric charge (anionic, cationic or non-ionic).
Stage 3 (Clarification):
Last but not least we are now at the clarification stage. In this stage we use our conventional methods to seperate solids from wastewater. Different methods can be used here but we often like to use our ClearFox Clarifier because it has the advantage to require minimal space and be very cost-efficient.
Using this method we can remove about 90% of the suspended solids, ~70% of BOD, ~40% of COD and all nutritients. These statistics meet the requirements for treated wastewater for every country in the world. Our objective here at ClearFox is always to find the correct solution specifically to every application with an optimal price-quality ratio.
We have delivered many of these treatment systems to various industries ranging from the food, fish and meat industry to the winery industry and more. If needed we can present you with corresponding job references to your industry. Please contact us so we can help you find a solution for your wastewater treatment problem and give you a free quotation.