Here’s a block diagram (flowchart) of a basic high pressure aeroponic system.
Let’s take a trip through the aeroponic system starting with the misters or nozzles.
First – Solenoids (Automatic valves)
The solenoids attached to the misters work as valves to open or close the flow of nutrient to the misters. Most solenoids are controlled by a computer or automated by an electronic timer. The solenoids turn on for short intervals to release the pressurized nutrients through the misters to create a fine mist that is sprayed onto the plant roots.
Second – Store it in the reservoir
Any nutrients not absorbed by the roots get returned to the reservoir at the bottom of the root zone by dripping through a drain with an inline filter.
The nutrient is stored here until the system calls for more pressure. The booster pump sucks nutrient from this reservoir and pressurizes it up to about 100 psi.
Monitor nutrient level
As the nutrient is used and as the plant grows, your reservoir will drop lower and lower. So any makeup water and nutrient needs to be watched here. As the reservoir drops in level, add more water here. A water level sensor could be used to monitor the nutrient and signal you when it’s time to add more.
Main component – Pressure Pump
The pump will send the pressurized nutrient to the pressure tank which acts like a big bladder that expands like a tough balloon. The tank works like a collector for the pump so that the pump does not have to work all the time. Without the tank, your pump would run every time the misters operated.
Now at the Tank
Since the tank is pre-pressurized with the nutrient, when the misters call for nutrient at 100 psi, it would be there instantly. Without the tank, the pump might take some time to build the nutrient up to 100 psi. Thus, your roots will not get the right water droplet size of less than 50 microns.
Sensing system pressure
Here is a good place to put a pressure sensor to monitor system performance between the pump and the tank. This sensor will tell you if the pump is functioning and that the system is activated. The sensor could work in unity with the pump to control its operation to maintain 100 psi.
Keep it clean – filter it
The pressurized nutrient now passes through an inline filter to remove any solids before the nozzles. These misting nozzles have a very small orifice (tiny hole) that could clog easily if there were stuff floating around in the nutrient. So removing it here will prolong a health spray.
Repeat it again through the system- Recycle it
Now we are back to the solenoids that control the misting to the root zone. This cycle gets repeated and continues by reusing any nutrient that is returned into the reservoir.
The ideal would be to spray just enough nutrient to feed the roots and have nothing returned to the reservoir. However, this would be very difficult and expensive to accomplish.
Pressurization, A Key Component to atomizing the nutrient
The nutrient is stored in the reservoir and pressure tank. The pump activates when ever the pressure to the system drops below a certain threshold. Let’s say 80 psi and turns off at 105 psi. This is normally controlled independent of the system computer but could be governed by the system controller.
As the nutrient is used on the roots, the pressure in the system will start to drop. The booster pump will now kick on to make up the pressure drop.
As the pump runs, it will siphon nutrient from the reservoir of the leftover nutrient that dripped off from the root zone to the aeroponic system.