Waterloo EC-P™ (Residential)
Electrochemical phosphorus removal for individual homes and cottages
The Waterloo EC-P™ is a patent-pending process for efficiently and permanently removing phosphorus from septic systems. The Waterloo EC-P represents an entirely new phosphorus removal strategy that is ideally suited for use on individual, small flow septic systems. This process mimics the natural phosphorus removal of iron-rich ‘B-horizon’ soils by introducing iron to any naturally iron-free filtration media. With the Waterloo EC-P up to 99% of total phosphorus can be removed from septic systems.
How It Works
Through electrochemistry the Waterloo EC-P removes phosphorus by the precipitation of iron-phosphate minerals. Natural iron electrodes are installed in the septic tank or in a small chamber immediately thereafter and a small current is applied to the electrodes. The iron is dissolved into the sewage stream where it reacts with phosphorus to form highly stable and insoluble iron-phosphate minerals. The Waterloo EC-P effluent is then passed through a filtration component, such as a Waterloo Biofilter treatment unit or conventional leach field or sand filter, where the iron-phosphate minerals precipitate out preventing phosphorus from reaching the natural environment.
Works with both Waterloo Biofilter and conventional septic systems
No additional sludge production
No chemical addition
No reactive medium disposal issues
Compact and easy to install
Can easily be retrofitted
No effect on pH
Low energy consumption (< $25/year)
Phosphorus is permanently contained in filtration medium rather than having to be treated again
Typically 2-3 year electrode life
Abiotic and independent of temperature
Conventional Phosphorus Removal Methods
Conventional strategies for removing phosphorus from onsite wastewater streams include chemical addition and reactive media, unfortunately these processes are not well suited for onsite septic systems.
The controlled addition of aluminum, iron or calcium salts to wastewater removes phosphorus by chemical precipitation. Subsequent flocculation and settling of these precipitates prevents the phosphorus from being released into the environment. This process however has a number of drawbacks including increased sludge production (and tank pump outs) by up to 40%, high O&M costs related to chemical transportation, storage, handling, and dosing, as well as the need for large tanks or clarifiers for settling of solids. Depending on the chemical used, a pH buffering chemical may also be required. Additionally, the phosphorus-rich sludge must be pumped out and subsequently treated again at municipal wastewater treatment plants.
Reactive media with naturally high concentrations of the above metals such as iron-rich B-Horizon soils or slag by-product can also be used to remove phosphorus, however these processes can also greatly alter the pH of the water and all have a limited lifespan, after which the material must be excavated, replaced, and disposed of elsewhere.