Juan José Magán's talk at the FERTINNOWA conference: Sharing fertigation best practices across Europe

1. This project has received funding from the European Union’s Horizon 2020 research
and innovation programme under grant agreement No 689687
Fertigation technologies:
the Almeria case
Juan José Magán

2. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Introduction
• In few decades fertigation technology in Almeria has changed from flood irrigation
to modern automatic fertigation controller, passing through derivation tanks for
fertilization.
• Automatic fertigation controller is a technology well accepted by growers in
Almeria.
Percentage distribution of the different fertigation
systems in Almeria (García-García et al., 2016)
Automatic controller
Fertilization tank
Manual Venturi
Irrigation timer
Injection pump
Direct aspiration

3. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller based on Venturi effect
• This is the most popular type of fertigation controller in Almeria because of its
lower price.
• They do not usually incorporate mixing tank.
Parallel connection with the discharge pipe (above) vs
parallel connection with the pump of automatic irrigation
equipment (below) (R. Baeza, 2018)

4. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller based on Venturi effect
• Differences in pressure between Venturi injectors promote differential injection.
• This can be solved by using circular configuration of injectors instead of linear.

5. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller based on Venturi effect
• Differences in height between the stock solutions in their respective tanks also
promote differential injection.
• This can be solved by preparing stock solutions to be injected in the same
proportion (e.g. A/B tanks).
• However, exact quantities of fertilizers have to be weighed for the preparation of
the stock solutions.

6. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller based on Venturi effect
• In Almeria most of the growers use multiple tanks for the preparation of the stock
solutions, varying the injection rate between them.
• In this case, the effect of the height differences on injection can be solved by
installing small intermediate tanks with a float valve.

7. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller with magnetic pumps
• A more accurate alternative is the use of fertigation controllers with level pipes.
• They use small magnetic pumps to drive the stock solutions towards vertical pipes.
The solutions are injected in a mixing tank from these pipes by gravity.
Photo credit: D. Amate, ANECOOP

8. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller with magnetic pumps
• The level pipes can be eliminated, thereby directly injecting the solution from the
magnetic pump into the mixing tank.
• Nozzles reducing the diameter of the entrance of the concentrated solution to the
mixing tank can be installed to generate a resistance which increases the
uniformity of the flow driven by the different magnetic pumps.
Photo credit: A. Marhuenda, INTA

9. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller with magnetic pumps
• A flow meter can be installed per magnetic pump, which allows the amount of
concentrated solution injected to be measured and the dosage adjusted, thereby
improving injection accuracy.
• These flowmeters can be also installed in automatic controllers with Venturi
injectors.
Photo credit: A. Marhuenda, INTA

10. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller with injection pumps
• Injection pumps can be also installed for the injection of the stock solutions. There
are two types: membrane and piston.
• The volume of the chamber is known, so that it is possible to know the volume of
solution injected by counting the number of pulses.
• These pumps are more expensive than magnetic pumps and require more costly
maintenance because the membranes and valves tend to get dirty and worn away
frequently due to the fertilizers.
Source:
www.google.es/search?q=esquema+bomba+de+membrana+riego&rlz=1C1EKKP_enES762ES762&biw=1366
&bih=626&tbm=isch&source=iu&ictx=1&fir=SDkcS7eKwLIiSM%253A%252CPNCeDI24oQ6PaM%252C_&usg=
AI4_-kTETCqqAozK_1sgVKFwlhHW6ZpxKg&sa=X&ved=2ahUKEwje_YSjh87dAhVH-
YUKHUjWATwQ9QEwAXoECAQQBg#imgrc=D5bY6bnPZCULlM:

11. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller with injection pumps
• Navaferti was the first automatic fertigation controller using injection pumps
developed in Almeria in the 90’s.
• It was developed for liquid fertilizers but the system never was very extended.

12. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller with injection pumps
• Fertilizer injection can be related to the water flow by installing a flowmeter,
electrically connected to the fertigation system, in the irrigation pipe. Knowing the
injected flow of fertilizers and the irrigation flow, the ratio between them can be
calculated and the injection of fertilizers can be automatically adjusted on-line to
achieve the desired proportion.
• If the stock solutions are injected directly in the irrigation pipe, it is necessary to
take into account the pressure in this pipe as it affects the injected volume.
Photo credit: A. Marhuenda, INTA Source: www.itc.es/es/electric/item/420-
acc070-bancada-de-dosificaci%C3%B3n-y-
control.html

13. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Automatic fertigation controller with injection pumps
• Fertigation equipments with injection pumps are more adequate with liquid
fertilizers than solid.
• If solid fertilizers are used, we must install mechanical mixers instead of a blower in
order to achieve an adequate solubilization of the fertilizers.
• It is also recommended an adequate filter to be installed in the aspiration of the
injection pump.

14. This project has received funding from the European Union’s Horizon 2020 research and innovation
programme under grant agreement No 689687
Thank you very much for your
attention