WO2008015674A2

WO2008015674A2 - Drip-irrigation emitter device

Info

Publication number: WO2008015674A2
Application number: PCT/IL2007/000958
Authority: WO
Inventors: Itzhak Agadli
Original assignee: Itzhak Agadli
Priority date: 2006-08-01
Filing date: 2007-07-31
Publication date: 2008-02-07
Also published as: IL177202A0; WO2008015674A3

Abstract

A dripping irrigation-emitter composed and constructed of a porous material, a construction that enables the containment of water and having the characteristics to have the water pass through the porous material from the construction to its surrounding.

Description

DRIP-IRRIGATION EMITTER DEVICE

FIELD OF THE INVENTION

[0001] The present invention relates to porous irrigation emitting units used in drip irrigation systems.

BACKGROUND OF THE INVENTION

[0002] In agriculture, drip or trickle irrigation is a widely used method of distributing water directly to roots of plants or trees at a slow rate, without substantial surface run off of the water, and with minimal evaporation of the irrigation water. To effect the slow application of irrigation water, the water distribution lines include emitters having extremely small orifices therein. As the soil surround the emitters becomes saturated an increase in hydraulic pressure is required for water discharge. In order to substantially increase the efficiency of the irrigation system, typically water at a pressure of 3 /4 atmospheres is provided to the distribution lines.

[003] The customary irrigation-emitter is composed of a water-conduit labyrinth or another mechanism that reduces the water pressure of the distribution lines to a relatively low pressure that enables a slow discharge of water to the soil. As the moisture increases the pressure required for continued discharge increases and the water flow reduced until no further flow is obtained. To overcome blockage it is customary to irrigate in pulses rather than continuously so as to allow the soil surround the emitters to partially dry. The requirement of hydraulic pressure and pulse irrigation dictate the necessity of pressure pumps and computerized control systems, thus making drip irrigation systems expensive and relatively complicated to operate.

[004] It is believed that continuous irrigation is far better than periodic irrigation and the resulting crop is exceedingly greater.

[005] An object of the present invention is to provide a relatively low cost drip emitter device. [006] Another object of the present invention is to provide such a drip emitter device that is simple to produce, resistant to clogging by contamination, easy to deploy and to operate, and facilitates continuous irrigation.

[007] More advantages and features will become apparent after reading the present specification and after considering the accompanying drawings.

SUMMARY OF THE INVENTION

[008] A dripping irrigation-emitter composed and constructed of a porous material, a construction that enables the containment of water and having the characteristics to have the water pass through the porous material from the construction to its surrounding.

[009] The emitter being composed of porous ceramic material, porous clay material, porous glass material or porous plastic material.

[0010] The emitter being constructed in a configuration so as to increase the surface area. [0011] There is thus provided, in accordance with some preferred embodiments of the present invention, a drip-irrigation emitter device comprising:

[0012] a porous vessel having at least an inlet for fluidical connection to a water supply pipe at a given supply pressure level so as to have the water pass through the pores from within the vessel to its surroundings at substantially similar pressure level.

[0013] Furthermore, in accordance with some preferred embodiments of the present invention, the vessel is made from materials selected from a group of materials consisting of ceramic, clay, glass.

[0014] Furthermore, in accordance with some preferred embodiments of the present invention, the device is further provided with an outlet, for serial connection to the water supply line.

[0015] Furthermore, in accordance with some preferred embodiments of the present invention, the device is formed in a tubular shape. [0016] Furthermore, in accordance with some preferred embodiments of the present invention, the device has a cross section of peaks and troughs.

[0017] Furthermore, in accordance with some preferred embodiments of the present invention, there is provided a drip-irrigation system comprising a plurality of drip-irrigation emitter devices the emitter devices each comprising a porous vessel having at least an inlet for fluidical connection to a water supply pipe at a given supply pressure level so as to have the water pass through the pores from within the vessel to its surroundings at substantially similar pressure level.

[0018] Furthermore, in accordance with some preferred embodiments of the present invention, there is provided a method for producing a porous drip-irrigation emitter device, the method comprising:

[0019] mixing of ceramic material with saw dust particles or polymer grains; [0020] hardening the ceramic material in the form of a vessel of desired shape; and

[0021] eliminating the saw-dust particles or polymer grains by exposing the hardened ceramic material to extreme temperatures thus burning out the saw dust particles, leaving vacuoles in the formed vessel, through which water may slowly pass in laminar flow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to better understanding the present invention, and appreciate its practical applications, the following Figures are provided and referenced hereafter. It should be noted that the Figures are given as examples only and in no way limit the scope of the invention. Like components are denoted by like reference numerals.

[0023] Fig. 1 is a schematic illustration of the external view of a porous irrigation-emitter in accordance with a preferred embodiment of the present invention.

[0024] Fig. 2 is a schematic illustration of the internal view of a porous irrigation-emitter shown in Fig. 1 DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0025] The present invention is directed at a porous irrigation-emitter that differs from the technology of "injecting" water to the soil by a pressure gradient from the distribution lines through labyrinths of the irrigation-emitter. Instead of "forcing" the water in the soil the emitter of the present invention is a construction having a relatively large surface area with walls being porous so as to allow the irrigation water to passively seep through the walls into the soil in osmosis. After initiation of irrigation, as the soil surrounding the emitter becomes saturated, the seeping from the porous walls of the emitter becomes a continuous trickle until the level of saturation equals that of the saturation level of the emitter, in accordance to the volume of water that the surrounding soil is capable of absorbing during lengthy time intervals.

[0026] The use of the irrigation-emitter of the present invention enables continuous water out- flow at a very slow rate (can reach a typical rate of less than 3-4 liters per hour for extended periods of time). The slow, continuous trickle enables the utilization of irrigation water more efficiently and by so doing increases the yield of crops.

[0027] The emitter effectively serves as a filter, for it allows only water to trickle out of the device.

[0028] The irrigation-emitter of the present invention enables the operation of a drip irrigation system independent of the availability of an electrical supply and the reliance on pressure pumps and computerized controlling systems, thus making its use beneficiary in developed as well as in under-developed countries and locations.

[0029] Typically a drip-irrigation emitter in accordance with a preferred embodiment of the present invention comprises a vessel made of porous walls embedded in the soil at predetermined locations near roots of plantations, and fluidically connected to a water source. The wall (or walls) of the vessel comprise vacuoles - voids in the wall material - that are distributed substantially homogenously throughout the wall and allow laminar flow of water from within the vessel to the outside into the surrounding soil in osmosis. The material from which the vessel is selected permits laminar flow between the voids. [0030] The drip-irrigation emitter of the present invention is preferably serially connected, having an inlet for receiving water from an adjacent pipe and an outlet for forwarding water to the next emitter. Li an alternatively embodiment a drip irrigation emitter comprises a single inlet fluidically connected to a water supply pipe that serves for water supply into the emitter whereas excessive water flows through the pipe to the next emitter. A drip irrigation system according to a preferred embodiment of the present invention may include both types of emitters.

[0031] An irrigation-emitter according to a preferred embodiment of the present invention is constructed of ceramic material, but other materials may also be used for the construction of the emitter.

[0032] Fig. 1 is a schematic illustration of the external view of a porous irrigation-emitter in accordance with a preferred embodiment of the present invention.

[00033] The emitter shown in Fig. 1 (and Fig. 2) comprises a hollow circular symmetrical and elongated tube 10, with an imaginary axis 50. In order to increase the surface area, the tube is constructed with a series of depressions forming apexes 50 and troughs 60 along the tube 10. The apexes and troughs along the tube form two symmetrical and opposite waves along the axis 50 when a cross cut of the tube is observed, as shown in Figure 2. The outer surface of the emitter 30 has typically the same porous characteristics as the internal surface 40. The porous wall of the emitter 70, is substantially homogenous and has, for most irrigation purposes, a thickness of 6 to 10 millimeters (without limiting the scope of the present invention to other dimensions that are possible too).

[0034] hi a schematic enlarged segment of the emitter wall 12 in Fig. 2, the homogenous porous characteristics of the external wall 30 and internal wall 40 of the emitter are demonstrated (with vacuoles 14 shown). Substantially homogenous porosity is kept throughout the entire thickness 70 of the wall of the emitter.

[0035] The tube terminations of the emitter on both sides comprise protruding, relatively small diameter, toothed conduits 20 one - upstream - serving as an inlet and the other - downstream — serving as an outlet. Both terminations allow firmly securing to distribution water lines. [0036] Fig. 2 is a schematic illustration of the internal view of a porous irrigation-emitter shown in Fig. 1.

[0037] In another configuration the irrigation-emitter is composed of porous clay. [0038] In another configuration the irrigation-emitter is composed of porous glass.

[0039] Other embodiments can be made from other materials that can display porosivity.

[0040] The drip irrigation emitter of the present invention is preferably used in connection with a passive water supply that depends solely or at least mainly on gravitation-induced water pressure. As water fills the emitters the gravitational pressure forces water to seep through the pores at a very slow rate. This can actually be described as "perspiration" of water from the emitter.

[0041] One alternative method of producing a porous emitter, according to a preferred embodiment of the present invention comprises mixing of clay with saw dust particles or other organic particles, or polymer grains hardening the clay in the form of a vessel of desired shape and eliminating the saw-dust (or other organic material or polymer grains) particles by exposing the hardened clay to extreme temperatures (typically in an oven) thus burning out the particles, leaving vacuoles in the walls of the formed vessel, through which water slowly passes (in osmosis).

[0042] It should be clear that the description of the embodiments and attached Figures set forth in this specification serves only for a better understanding of the invention without limiting its scope.

[0043] .... (repetition of [0042] omitted)

[0044] It should also be clear that a person skilled in the art, after reading the present specification could make adjustment or amendments to the attached figures and above described embodiments that would still be covered by the present invention.

[0045] .... (repetition of [0044] omitted)

Claims

1. A drip-irrigation emitter device comprising: a porous vessel having at least an inlet for fluidical connection to a water supply pipe at a given supply pressure level so as to have the water pass through the pores from within the vessel to its surroundings at substantially similar pressure level.

2. The device as claimed in claim 1 , wherein the vessel is made from materials selected form a group of materials consisting of: ceramic, clay, glass.

3. The device as claimed in Claim 1, further provided with an outlet, for serial connection to the water supply line.

4. The device of claim 3, formed in a tubular shape.

5. The device of claim 1, formed in a tubular shape.

6. The device of claim 5, having a cross section of peaks and troughs.

7. A drip-irrigation system comprising a plurality of drip-irrigation emitter devices the emitter devices each comprising a porous vessel having at least an inlet for fluidical connection to a water supply pipe at a given supply pressure level so as to have the water pass through the pores from within the vessel to its surroundings at substantially similar pressure level.

8. A method for producing a porous drip-irrigation emitter device, the method comprising: mixing of ceramic material with saw dust particles or polymer grains: hardening the ceramic material in the form of a vessel of desired shape; and eliminating the saw-dust particles or polymer grains by exposing the hardened ceramic material to extreme temperatures thus burning out the saw dust particles, leaving vacuoles in the formed vessel, through which water may slowly pass in laminar flow.

9. The method of claim 8, wherein the ceramic material comprises clay.

10. A drip-irrigation emitter device substantially as described in the present specification and accompanying figures.

A method for producing a drip-irrigation emitter device substantially as described in the present specification and accompanying figures.