BioMedia Filtration System – Gravity filters with BioMedia®

Filtration is the final step in a standardized water treatment system. Most commonly, we use gravity filters based on BioMedia®, though in certain applications we also implement sand filtration solutions. For specific types of PFAS contamination, we can apply a unique ion-exchange technology. The type of contaminants present determines the choice of filtration stage.

Gravity filtration

BioMedia® filtration is often deployed as a second major treatment step following chitosan flocculation and the consequent sedimentation process. The standard BioMedia® filters are typically delivered in practical filter modules, with a size around 1 m³ per filter. Each filter module has the capacity to treat approximately 6 m³ per hour, depending on the incoming water quality and levels of contamination.

Incoming contaminated water is pumped to the BioMedia filters for treatment. The water is then gravity-filtered through the filter modules to remove both particles and dissolved pollutants. Since the filters are not pressurized and only use gravity, smaller pumps can be utilized which requires less energy than typical pressurized filters. After filtration, the treated water can be discharged to recipient, meeting the toughest regulatory standards.

Extended lifespan

Since BioMedia® filters are not pressurized and only use gravity flow, any residual particles present in the incoming water will not be pushed or forced into the filter bed. Instead, particles accumulate on top of the filter bed. This allows for easier service and maintenance, where the top layer of the filter can simply be cleaned or replaced. This means that the filter will last for a long time, also avoiding time-consuming filter changes as often required by other solutions on the market.

In a Swedish Hydro Solutions water treatment set-up, the BioMedia® filters are often used as a second treatment step after chitosan treatment. This means that most of the particles in the incoming water never even reach the BioMedia® filter.

If the consumed filter media does not contain harmful substances, it can be used as a soil amendment material. The BioMedia® can also become an excellent soil culture medium, considering it provides a good environment for microbes and mycorrhiza and prevents nutrient leakage for plants. BioMedia® also serves as a carbon sink, since it is stable for thousands of years and does not break down to release carbon dioxide. In addition to keeping our water clean, this is an extraordinary advantage.