Clean water is essential to food production. From irrigation through processing and preparation, the water used must be free from biological, chemical and sedimentary contaminants.
Volunder has developed a flexible design for multi-stage water filtration systems. Our latest design includes a biosand filter and an activated charcoal filter. The biosand filter is effective at removing biological contaminants, such as protozoa, bacteria (including E. coli), and some viruses from the source water. The charcoal filter is effective at removing chlorine, benzene, solvents and many pesticides and herbicides. Both filters remove sediment, reduce turbidity and improve odor and taste.
The filter structures are built from schedule 40 pvc. Each has a 4″ layer of coarse rock (~1″ diam.) at the bottom folllowed by a 4″ layer of gravel (~1/4″). The final layer depends on the filter type. In the biosand filter there is a 12″ layer of sand while in the charcoal filter there is a 12″ layer of activated charcoal, in our case made from coconut shell.
The filters can be joined together to form a robust filtration capability with a small footprint and economical energy usage. In this case, the biosand filter must come before the charcoal filter, as it is the slower of the two.
Plans are being developed for an ultraviolet filter stage, which would have an effect similar to the biosand filter but would have a greater throughput at the expense of greater energy consumption.
The hapi platform is being extended to provide native support for filter management, using level switches and a small pump. This will be included in the v2.0 final release.
Here is the design for base model filters:
The 3D model file is available upon request.
HAPI (Hydroponic Automation Platform Initiative) is an open-source project of the Open Community Development Corporation.