Chitosan – derived from crab shells

Chitosan is a water‑soluble polysaccharide that effectively treats water containing particles and particle‑bound contaminants through flocculation and sedimentation. It is a fully biodegradable and naturally occurring substance extracted from crab shells. In the United States, chitosan‑based water treatment is classified as a Best Management Practice (BMP) for stormwater treatment.

A safe flocculant

Our chitosan is extracted from crab shells, a by‑product of the food industry. The substance has long been used in medical applications, such as wound dressings, and even as a thickening agent in food. Chitosan is fully biodegradable and completely safe for both human health and the environment.

Suitable for many industries

Sedimentation with chitosan flocculation is highly effective wherever turbidity is a challenge, including:

  • Construction projects
  • Civil engineering works
  • Remediation projects
  • Industrial sites
  • Forestry operations

How chitosan flocculation works

Chitosan has chemical properties that make it an extremely effective flocculant for particles and particle‑bound contaminants in water. When chitosan binds to particles, they flocculate — meaning they cluster together into larger, heavier flocs that then settle rapidly.

Chitosan dosing occurs as the first step in Swedish Hydro Solutions’ treatment systems. After flocculation and sedimentation, a BioMedia® (r) filter can be added when needed to remove dissolved metals and organic pollutants. Chitosan flocculation works equally well for low and high water flow rates by adjusting the chitosan dosage.

  1. Turbid water is pumped into a Swedish Hydro Solutions HydroBox
  2. Inside the HydroBox, the water passes over chitosan dosing cartridges
  3. Chitosan is passively released into the water from the cartridges
  4. The water is then pumped to sedimentation tanks
  5. Chitosan causes particles to flocculate
  6. The particle flocs settle to the bottom
  7. The treated water is discharged — or pumped onward to BioMedia® filtration if required

Want to learn more?

Are you looking for an efficient and eco-friendly water treatment solution? Get in touch with our sales team and we’ll help you get started.

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