Solar Valve

The flooding and draining cycles of cell 2 are controlled by a solar powered mechanical valve installed within the outlet drain of the cell. Both the depth and time of flooding can be controlled to influence the flow of nitrogen and phosphorus.

Increased flooding time will increase the transformation of liquid nitrogen to gas and cause phosphorus that may be bound to sand or brick particles to become mobile. Decreased flooding will cause nitrogen to remain in its liquid nitrate form and cause phosphorus to stay bound to sand or brick particles.

We are evaluating solar power for installations in areas without electricity and for its potential in other settings. The use of solar energy to move water has a number of advantages, including increased energy storage not typically provided by batteries.

Splitter Valve

The splitter valve regulates the nitrification-denitrification process by releasing or recirculating wastewater so that the microbes responsible for transforming nitrogen maintain a balanced diet of carbon, nitrogen, and phosphorus. Recirculation back through the septic tank and on to cells 1 and 2 provides a healthy new serving of carbon to reinvigorate nitrogen processing.

The ratio of released to recirculated water depends on measurement of the nitrate level at the exit drain of cell 2. If too much nitrate is present then a large portion of the water will be recirculated to take advantage of the reservoir of carbon in the septic tank needed by the nitrate-processing microbes, otherwise most of this water will be sent to the ultraviolet disinfection unit and on to the greenhouse.