Frequently Asked Questions

Buried Diffusers FAQ


If you didn't find the answer to your question on this page, please contact our team.

General


Buried diffuser


Technical

General


We will soon publish the list of all our partners/distributors. Meanwhile, please contact us.


We are always looking for serious partners to distribute the Buried Diffuser. If you are interested please email us with details about your company, your current activities, your country... All serious propositions will be studied.


Yes, Chahtech include a warranty in the packaging.


No because the installation is simple. Chahtech provides installation manuals and supports for all its customers. 

The Buried Diffuser has been tested in arid and semi arid regions in Tunisia during several years with farmers on several crops.

    • On trees: olive, orange, citrus, date palm, grape, fig, cherry and pear.
    • Vegetables: melon, water melon, potatoes, pimentos and cucumber.

Several customers started using The Buried Diffuser for the irrigation of already tested crops but also on new ones (vegetables and trees) such as mango, papaya, litchi, almonds, kiwi, nut, kaki, berry, apple, strawberry etc. This will be done in Morocco, Kenya, South Africa, Zimbabwe, Mali, Senegal Oman, Saudi Arabia, USA, and China.


Buried diffuser


The difference between these two diffusers is the size of the diffusing surface and the volume of the diffused water per hour:

    • 400 square centimeters for The 15/30 Diffuser. The water volume diffused per hour is 8 litters (maximum) if used for trees and 4 litters (maximum) if used for vegetables.
    • 200 square centimeters for The 15/15 Diffuser. The water volume diffused per hour is 4 litters (maximum) if used for trees and 2 litters (maximum) if used for vegetables.

No. Only The Pot Diffuser have a reservoir.

The differences are:

    • Depth of burying: 5 till 10 cm deep for vegetables and 50 cm deep for the trees. When you buy a diffuser: if it is for trees it is delivered with a 50 cm vertical 16 mm pipe; if it is for vegetables it is delivered with a 5 cm vertical 16 mm pipe.
    • The water flow regulator (emitter) is different this means that the volume of water diffusing flow is also different. For trees, the water flow regulator delivers 4 litters per hour for model 15/15 and 8 litters per hour or model 15/30. For vegetables, the water flow regulator delivers 2 litters per hour for model 15/15 and 4 litters per hour or model 15/30.

Yes, if you buy a diffuser for vegetables you can use it also for trees after changing the water flow regulator and the vertical 16mm pipe.


When used for vegetables, the concave parts of the shape are conceived to receive one plant. In 15/30 diffuser there are 2 concave parts; and in the 15/15 diffuser there is 1 concave part. When used for trees the concave parts has no purpose.


For vegetable and trees: The water coming from the water distribution pipe (16 or 20 mm diameter) cross the water flow regulator (part of The Buried Diffuser). The regulated flow of water (8 or 4 or 2 litters per hour) is transferred to the diffusing surface (200 or 400 or 100 square centimetres) which is in contact with the soil below. This diffusing surface composed of very porous plastic net retaining 5 mm of siliceous granulate. The irrigation water arriving in this granulates circulate through the macro pores, and then infiltrated in the soil below, along the diffusing surface.


All the components of The Buried Diffuser are made of virgin plastic materials (PP, HDPE, LDPE, and PVC) treated anti UV.


The buried diffusing part can be used for more than 30 years when used for trees and more than 5 years if used for vegetables. The connection parts (not buried) can also be used for more than 5 years.


Once installed correctly, no maintenance is needed. 


Burying the diffuser at 50 cm is valid for all kind of trees in the world. This depth is fixed according to root system distribution in rain fed and in irrigated crops. In both crops most (70 till 90%) of the root system is located in the first 60/70 cm of the soil. This is related to water availability from irrigation or from rain water infiltration. The second part of the root system (pivot root system, 10 till 30%) is in the soil layers, below 70 cm. This pivot root system is a life strategic system for the tree. It is used when there is no more water in the first 60/70 cm. The tree will “pump” the water, using the pivot system, from soil deeper then 60/70cm. This pivot system can reach a depth of several meters (3 till 10 meters). When we irrigate with The Buried Diffuser, the water is diffused at about 10 cm above the diffuser and below.


The diffused water amount is regulated by the water flow regulator connected to The Buried Diffuser (delivered in the package) and the water distribution pipe (16 or 20 mm diameter).


The underground drip system is also buried at 50cm, like the diffuser, but the water distribution is completely different:

    • In the case of the underground drip system, the drippers are incorporated in the pipe, every meter there is 1 dripper delivering 2 litters/hour. The water distribution is alongside the pipe. The roots have to follow the pipe even in space out of the canopy. There is a linear concentration of the roots in only 2 sides of the canopy. The 2 other sides are not explored by the roots. Besides the underground drip system needs the use of water pressure (2 bars), this is obtained by powerful pumps using a lot of energy.
    • In the case of The Buried Diffuser, the water distribution is more uniform around the canopy because the water distribution is not linear, it is “bulb”. This “bulb” can reach 1 till 3 meters diameters and 2 meters deep, depending on the volume of water delivered continuously. A field trial(in south of Tunisia), in a equilibrated and thick soil, showed that the “bulb” of one diffuser 15/30, after delivering 10 cubic meters has 6meter diameter and 3 meters deep. This distribution interests the 4 sides of the canopy. This induces a better roots distribution around the canopy and a better growth. The Buried Diffuser could work with low water pressure (gravity: 1/20 till 1/5 of bar) and does not need pumps. It needs just a reservoir (concrete, plastic or metallic), on the topographic level and 2 meters deep maximum. If a tree need 10 cubic meters per year, if we use the underground drip system, we use the pump during 250 hours. However, with The Buried Diffuser, this is completely saved: it works with gravity.

To conclude, The Buried Diffuser allows better water diffusion for the plant using less water and less energy.


The components of the 15/15 and 15/30 Buried Diffusers are:

  • 1 diffusing part (15/15 or 15/30)
  • 1 vertical 16 mm connection pipe (5 cm long for vegetables, 50 cm long for trees)
  • 1 water flow regulator (emitter)
  • 2 flexible pipes 5mm (5 till 7 cm long each)
  • 1 cork 16 mm
  • 1 gasket 5 mm
  • 2 connectors 5 mm
  • 1 connector 16 mm

The dimensions of the different models of The Buried Diffuser are:

    • 15/15 Diffuser: a square shape with 15 cm side.
    • 15/30 Diffuser: a rectangle shape with one side of 15 cm and second side of 30 cm.
    • Pot Diffuser with mini reservoir: a half circle shape with a diameter 30 cm.

In normal soil without rocks and gravels, the installation needs less than 15 minutes.


The existing diffuser with mini reservoir for pots and containers has a diameter of 30 cm. You can use it in pots or containers with a diameter or side larger than 30 cm.


The capacity of the mini reservoir of The pot Buried Diffuser is 120 cl.


The Buried Diffuser could not be used with geothermal water. This kind of water should be cooled till 25° to be used for irrigation using The Buried Diffuser.


Technical

This means that if with drip irrigation you use 300 litters to produce 10 kg of pimentos, by using the buried diffuser you need only 100 litters to produce 10 kg of pimentos.


The Buried Diffuser can't be used for lawn.


The Buried Diffuser can be used for all kind of trees such as banana, mango, papaya, litchi, guava, avocado, ficus indica, pomegranate, date palm, oil palm, apple, apricot, grape, olive, orange, citrus, almond, nut, pear, fig, etc.


The Buried Diffuser can be used on many vegetables such us pimentos, melon, water melon, cucumber, tomatoes, marrow, courgette, gumbo, potatoes. The Buried Diffuser is not advised to be used for carrot, persil, spinach, flop, onion, garlic.

If the distance between the trees is les than 3 meters, you need only 1 diffuser. But if the distance between the trees is more than 4 meters:

    • you need 2 diffusers, if the canopy diameter is less than 2 meters
    • you need 3 diffusers, if the canopy diameter is more than 2 meters till 4 meters
    • you need 4 till 5 diffusers, if the canopy diameter is more than 4 meters

        You need to buy the classical water distribution pipe (16 or 20 mm diameter) to which the diffusers will be connected.


The Buried Diffuser is recommended for organic farming because it reduces weeds and diseases development. This helps a better growth of the plants without using herbicides, pesticides and other chemical products.

Please read the following document: http://www.chahtech.com/doc/en/Buried-Diffusers-Advantages-Compared-With-The-Drip-Irrigation.pdf


The Buried Diffuser reduces diseases because there is no wetted soil and no weeds. In green houses, since there is no water evaporation from The Buried Diffuser, water vapor in the atmosphere is considerably decreased. This reduce the appearance and propagation of diseases such us mildiou.


If you have a water distribution pipe network (16 or 20 mm diameter) with non incorporated dippers (the drippers are added) you do not need to change your drip irrigation network to install The Buried Diffuser.

If you have a water distribution pipe network (16 or 20 mm diameter) with incorporated dippers (the drippers are inside the pipe) you have to change your drip irrigation network to install The Buried Diffuser.


The roots will improve the water diffusion, because the growth of the roots will induce destruction of the soil structure around and alongside each root. This will facilitate the circulation and the infiltration of the irrigation water alongside each root.


When you irrigate using The Buried Diffuser the weeds growth could be completely stopped because there is no water in the subsurface soil. In comparison with drip irrigation, The Buried Diffuser reduces minimum 70% of weeds growth.


The water diffusion is related to soil physical characteristics of the soil. In a sandy soil, the diffusion flow is mostly vertical. In this case it is recommended to irrigate more frequent (but 2 times less frequent than drip irrigation) . In an equilibrated soil, the diffusion flow is uniform vertically and laterally. In a heavy soil the diffusion flow is more important laterally than vertically.


The 15/15 Buried Diffuser is for one plant, the15/30 model is for 2 plants.

You can measure this by doing a simple trial (with one or many trees of the same size) with 4 plots. In the first plot one (or more) tree is irrigated with the diffuser. In the second plot, one (or more) tree irrigated with another irrigation technique (frip, subsurface...). The first and the second plot have to be irrigated with the same water volume (V) during a year. In a third plot, trees irrigated with 30% of water volume (V) using buried diffuser. In a forth plot, trees irrigated with 30% of water volume (V) using another technique (drip, subsurface...). After the harvest you compare the yield in the different plots.


Chahtech is preparing a special diffuser for landscaping which wil be available in 2014.


Yes but only for vegetables.


The different usual methods to automate the irrigation can be used with The Buried Diffuser. But the simplest way to automate the irrigation without any sophisticated devices or installation is the use of the gravity and the anticipated irrigation. Just fill a reservoir and start you irrigation day and night without any energy. When the reservoir is empty, you refill it.

    The "Anticipated Irrigation" is a new irrigation technique only allowed with The Buried Diffuser. In fact, instead of irrigation during the hot or the dry season, the irrigation using buried diffusers is done during the autumn and winter or during the rainy season when water is available. The amount of water of the anticipated irrigation should cover the total need of the crop during the hot or dry season (spring and summer). This water amount is stored in the deep soil layers and will be used by the deep or sub surface roots systems of the crops. The anticipated irrigation is recommended only if the soil below 50/60 cm contains minimum 10% clay.

    The "Water injection in the deep soil layers” is useful especially for trees crops. The injected water comes from: dams, rivers, and springs. The amount of the injected water could cover the need of the trees for several years (3 years) when the soil below 50/60cm is thick (1 meter or more). This injected water is conserved in the deep soil layers (50/60 cm below the soil surface) and used later by the deep root systems of the trees during a long drought period: six months till 3 years. During the Drought the trees produce normally using the injected water. The anticipated irrigation is recommended only if the soil below 50/60 cm contains minimum 10% clay.

What is the required filtration system?

The required filtration system should retain any particle which size exceeds 100 microns.


What is the required water pressure when using The Buried Diffuser?

The buried diffuser is delivered with 2 options of water pressure:

  • Option 1: water pressure between 0,5 and 1 and half bar.
  • Option 2: the Buried Diffuser works fine with gravity. In this case there is no need of a pump. The network is connected to a small or a big reservoir installed half meter above the soil. The maximum water depth should not exceed 3 meters. According to that the water pressure varies from 1/10 till 3/10 of bar.

If you didn't find the answer to your question on this page, please contact our team.