The most widely used were the following devices:
- Injector of the Venturi type;
- Fertilizer capacity;
- Proportional pumps, dispensers.
Injector type Venturi
It is a tube with tapers on both sides, working on the principle of pressure drop. It is made of polymer materials resistant to aggressive media. The injector is installed in the system on the fertilizer head, which allows you to separate the irrigation and fertigation processes (application of fertilizers and chemicals with irrigation water).
The flow passing through the injector creates a negative pressure (vacuum), which draws the chemical solution into the channel, where it mixes with the passing water and is introduced into the system.
When installing the injector, pay attention to the direction of the arrow. For normal operation, the pressure at the inlet to the injector must be at least 2 Atm, the minimum volume of water passing through the injector should be 0.7 m3 / h for the 3/4 “model and 3 m3 / h for model 1”. The more the valve on the fertilizer head is covered, the higher the pressure drop, and, correspondingly, the intensity of intake of the injector. The “Venturi” type injector gives a relatively good uniformity of mixing the mother liquor with the main water flow, and maintains the preset concentration throughout the time of the solution injection.
Fertilizer capacity
It is a hermetically sealed tank, which has cranes at the inlet and outlet. It serves to simplify the introduction of mineral fertilizers and other chemicals through a drip irrigation system. A small pressure drop created by the tap of the fertilizer head creates a parallel flow through the tank where water mixes with the substance and transfers it to the system. Fertilizer capacity is the most reliable and least fanciful in use. Its only drawback is the uneven concentration of the mother liquor. The solution entering the system initially has a high concentration, then it gradually decreases
The proportional pump dispenser
It is used for applying fertilizers and plant protection products through irrigation systems and guarantees high accuracy of their dosing. The device is mounted directly into the irrigation system, directly or through the fertilizer head. The working turbine is driven by water pressure in the system, (without electricity), as a result of which the dispenser draws a strictly defined amount of solution from the container, a homogeneous mixture is formed in the mixing chamber with water, which is fed further. The dispenser can be adjusted only once. Re-installation and external monitoring, it does not require. The amount of intake solution is constant and strictly proportional to the amount of water flow, regardless of the pressure, and therefore there is no risk of overdosing.
Benefits:
high uniformity;
does not require energy resources;
various sizes: 3/4 “, 1”, 1 1/2 “, 2”;
wide range of% values;
specialized solutions for acids and other chemical environments;
various installation options;
allows you to automate the fertilization process.
Automatic fertigators
Automatic fertigators are equipment for precise and metered application of fertilizers and other nutrients (including acids, plant protection products, biological products), used to prepare nutrient solutions in an automatic mode. They are widely used indoors and outdoors, as they allow you to simultaneously apply 6 (or even more) types of fertilizers, while controlling the pH and EC levels.
Depending on the specific model, the fertigator in automatic mode, according to the set program, can control the irrigation valves, control the water flow and the concentration of the mother liquor, control the water supply pumps and the irrigation system as a whole.
In general, this is the most functional and most accurate equipment, which is selected in accordance with the wishes of the customer.