GB2493970A

GB2493970A - Automated fertigation apparatus and system

Info

Publication number: GB2493970A
Application number: GB1114765.9A
Authority: GB
Inventors: Fabio Dias
Original assignee: STALWART TECHNOLOGIES Ltd
Current assignee: STALWART TECHNOLOGIES Ltd
Priority date: 2011-08-26
Filing date: 2011-08-26
Publication date: 2013-02-27
Anticipated expiration: 2031-08-26
Also published as: GB201114765D0; GB2493970B

Abstract

An apparatus for automatically controlling the irrigation and distribution of fertilisers into a plantation zone comprises two chambers 1, 2 that allows the flow of both fluids in variable proportions into a fluid mixer 7, with the resulting mixture used for irrigation of crops under the control of a solenoid valve 9 guided by a cyclical timer. The apparatus facilitates the automation of fertilization and irrigation of multiple crops having varying fertilization needs under a single water source and a single fertiliser source that can be distant from each other when connected into a system. The apparatus may include moisture sensors, sunlight or rain sensor and may be powered by solar energy 14. A system or method employing the afore described apparatus may be used in multiple irrigation zones.

Description

AUTOMATED FLEXIBLE FERTIGATION ArPARATUS AND SYSTEM

TECHNICAL FIELD OF THE INVENTION

[0011 The present invention relates to the technological field of apparatus and systems for irrigating and fertilising in an automated manner living plant material such as fruit crops, shrubs, trees and the like.

BACKGROUND

[002] It is a well-known practice to use automatic watering devices, such as sprinklers, in order to supply plants with a proper amount of moisture so that the crops will flourish. Homeowners and commercial establishments, such as golf courses, farms and recreational parks, are increasingly using automatic watering systems. A technique known as fertigation is also being increasingly used -on fertigation, the fertilisers are added to the irrigation water so that at one go the crops are both irrigated and provided with nutrients.

[003] A conventional irrigatLon control system employs a timer controller, which operates a solenoid valve incorporated into a water system so that when the time as arbitrarily set by thc user arrives, power is supplied via the solenoid to the water supply valve so that water is then supplied to a system of sprinklers or other irrigation devices. However, irrigation control systems are agnostic to the fluid they are being provided with, which means that when fertigation is done the fertilisers need to be injected to the main irrigation water prior to reaching the irrigation control, and for the irrigation controller everything happens as if normal water were being used.

[004] A number of systems have been developed to attempt to automatically control the variety of variable conditions that affect a fertigation system. The following patents exemplify some of the solutions.

[0051 U.S. Patent No. 6,507,775 issued to Tim Simon, Inc. on the 14th January, 2003, describes a method nowadays vastly used to control automatic irrigation by means of an irrigation timer and clock coupled to a powcr source and a set of solcnoid valves which control the delivery of water to sprinklers or drippers.

[0uJ6j U.S. Patent No. 7,093,606 issued to Kenneth J. Roberts on the 22nd August 2006, discloses a liquid fertiliser injector system that employs a holding tank connected to an inlet line. A collapsible impermeable bag is positioned within the holding tank to contain and segregate a distinct additive apart from the fluid entering the holding tank via the inlet line. Fluid from the inlet line causes communication of additive from the bag out an outlet line and into the fluid flow downstream of the inlet line. The water that reaches the irrigation control system has already the fertilisers blended with it in the appropriate proportions.

[007j International (WIPO) Patent Application Publication No. W02010US25533/20100226, published on the 02nd September 2010, describes a fertigation system that allows fertilisers to be mixed with irrigation water at irrigation time rather than prior to it, providing an integrated irrigation and fertilisation.

However it does not allow timed and/or automated control of the discharge of water and fertilisers, so it would require an additional controller in order to be a complete solution. It also has an issue that the fertilisers need to be put directly into the device, not allowing for a larger network of external sources of water additives, as such being unsuitable for large scale agroindustrial applications. Still, no obvious modification of this device to enable it to be part of a network would allow it to control of the proportions of the fertilisers used so that it can deal with different zones with different requirements, still using only one source of water and fertiliser.

[O8I There is still a genuine need to solve an operational issue arising in large scale fertigation due to the fact that fertilisers cannot be added into irrigation controllers in real time, in an integrated and automated manner. Before demonstrating how the proposed system and apparatus solve this problem, it's worth demonstrating with specific examples why there is a genuine need to solve this problem.

[009] The first problem arising from this lack of optimal integration between fertilising and irrigating can be seen when a farmer desires to irrigate multiple crops with substantially different water demand and fertilisation requirements between themselves. Sweet sorghum is reported to demand around half of the water and fertilisers as of sugarcane, however both arc used to produce ethanol via fermentation of their juices. Several large scale ethanol producers in Brazil are starting to have multiple crops of sugarcane and sweet sorghum to leverage on the fact that sugarcanc can only be harvested about six months per year (possibly eight if several different varieties, with different watering requirements, arc used in the same farm), whilst with proper irrigation and fertilisation sweet sorghum can be harvested on the exact other six months of the year that the sugareane is maturing, allowing a year round production of ethanol.

[010] This scenario leaves the aforementioned producers in a situation where they have to either install multiple fcrtigation systems or manually manage the fertigation by blocking part of the pumping when it's not required. There arc other options, like not doing any crop-specific control at all, sending the fertilisers as per the crop of highest demand at the expense of wasting redundant excessive fertiliser for the crop of lowest demand; or sending the fcrtilisers as per the crop of lowest demand and manually complementing the crop of highest demand; or simply scnding the average.

All the solutions are suboptimal regarding automation nonetheless.

[011] The second problem is more specific to the ethanol industry, but has potentially large environmental implications. The conventional production of agricultural ethanol involves in one of its final stages the distillation of a solution containing approximately 12% of ethanol into two separate solutions, one consisting of 96% ethanol (4% water), called hydrous ethanol, and a residual and highly pollutant chemical solution, called vinasse. For each litre of hydrous ethanol produced, eight to ten litres of vinasse are produced, with it becoming one of the most (if not the most) undesirable side pollutants generated during the process.

[012] Vinasse is a very hot and acid solution but rich in Nitrogen and Potassium.

Due to this, ethanol producers treat the solution, neutralising its acidity, reducing its temperature and filtering the remaining solids present in it. This treated vinassc is later on used in their own agricuhural plantation as a water additive for fertigation.

However, due to the sheer volume of vinasse produced in a relatively short amount of time, there are still environmental issues with this approach.

[0131 Because the additive needs to be put into the water source for the irrigation system, a serious environmental risk arises as this will require the construction of large areas where natural watereourses are dangerously near to polluting effluents.

Leakages are not uncommon and contamination can happen. In Brazil, many of these areas are known as "sacrifice areas". Moreover, once the water has been mixed with vinasse it can no longer be used for any other purposes, so any excesses have to be throwa into the soil anyway even if not needed.

[014] Many producers try to avoid this contamination risk by maintaining the production area far from the water source and, instead of doing fertigation, they simply load tank trucks with treated vinasse and manually sprinkle it into the soil.

This will cause, nevertheless, the problem of emissions by the trucks and also lack of precision when sprinkling the treated vinasse, with areas closer to production area normally receiving disproportionately high doses of the product (to minimise travelling by the tank trucks), which in turn causes severe contamination of the soil itself with excessive levels of Nitrogen, Potassium and various salts present in the vinasse composition.

SUMMARY OF THE INVENTION

[015] The present invention solves the problems mentioned before by proposing a method of irrigation of live plant material which includes: [0161 -providing a source of water for irrigation, [017] -providing a second source of fertilisers, diluted in a much smaller water bag or, as in the case of in-farm ethanol producers, treated vinasse (with the fcrtilisers already adjusted accounting for the amounts of Nitrogen and Potassium present in the treated vinasse), [0181 -distributing the water and the diluted fertilisers in separate pipelines that will contain fertigation controflers, connected along the said pipelines to networks of drip irrigation tapes or sprinkles, and [019] -controlling automatically the flow of water and fertilisets from the main pipes to the drippers or sprinklers by the use of timed solenoid valves, mixing in real time water and fertilisers prior to them reaching the solenoid valves and ensuring the correct proportion of water and fertiliser is used in the mix.

[020] The invention also provides an apparatus for controlling automatically the fertigation which includes: [021] -a dual chamber tank that would contain water in one chamber and diluted fertilisers in another, [022] -two adjustable flow control valves for controlling the volume of the flow of liquid from each of the chambers, [023] -a static fluid mixer that would use the gravity pressure from the accumulated fluids in the tank to blend them together into one single fluid to be sent to a solenoid valve that would flush the entire contents of the tank at timed intervals to a pump that would pump this mixture at higher pressure to the drippers or sprinklers, and [024] -optionally a solar energy generation connected to a battery to power the entire irrigation control system, ensuring fully clean and renewable energy usage and no need for wiring along the entire gild.

BRIEF DESCRIPTION OF THE DRAWINGS

[025] The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings: [026] Figure 1 is a perspective view of the irrigation apparatus for use in the irrigation system [027] Figure 2 is a lateral view of the apparatus showing the side where most of the controls are located; and [028j Figure 3 is a general diagrammatic overview of a possible disposition of the system in accordance with the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[029] Referring firstly to Figures 1 and 2 where the main irrigation control apparatus is illustrated, a dual chamber tank is shown, with the first chamber (1) being used to temporarily store fresh water and the second chamber (2) used to store fertilised water. Both are connected to the main pipeline, with fresh water coming from (3) and fertilised water coming from (4). There's no pre-speeified dimensions for the two chambers but it is expected the one that holds fertiliser to be smaller than the one that holds water. The fresh water leaves the tank from an exit in the bottom of it with a flow control valve (5), the same being valid for the fertilised water (6).

[030] The presence of a flow control valve is to assure the system can be used for multiple crops with different demands. Each zone would have its own apparatus but the crop that demands, for instance, half of the resources of the most demanding crop would have its flow restricted to only half of the flow of the most demanding crop.

The concept can be generalised for many crops and for many ratios of water and fertiliser. This is a simple but powerful way to ensure any possible combination of several different crops with several different demands of water and fertiliser can be catered for into the same system using several instances of the same apparatus connected to the main pipeline.

[031] The fresh water and the fertiliser water would flow into their respective pipes into a static fluid mixer (7), using the gravity pressure to facilitate the blending via the static mixer. The resulting mixture, henceforth called fertigation water, goes to a normally closed solenoid valve (8) that will stay closed until enough fluids have been stored in the dual chamber tank. Once opened, it will allow the fertigation water to go to a pump (9) that will boost the pressure of the fertigation water, exiting the apparatus by a connection (10) to the network of drip irrigation tapes or sprinklers.

[0321 The solenoid valve will open and close following continous cycles, controlled by a programmable digital timer (11). To save energy and avoid dry operation, the pump will also be controlled by the digital timer, given that no pumping is necessary when the solenoid valve is closed.

[0331 The aforementioned pump is somewhat optional, as it can be eliminated if the chamber is placed high enough from the ground (where the mixer and the solenoid valve are), creating natural pressure from the gravity force, and if the drip tapes connected to the exit of the apparatus are of a type that can operate with low pressure (for instance, microdrip irrigation tapes). Larger zones, though, can be accommodated using only one apparatus if a stronger pump is used, the timer is configured to use shorter cycles and the tank is larger.

[034] To enable connection in series (and drainage) in a large farm, both chambers in the tank will contain lateral exits, one for the excess fertilised water (12) and another for the excess fresh water (13). Optionally, the whole apparatus can be powered via solar electricity, with a solar panel (14) eoneeted just above the tank, linked to a battery charge controller (15), a battery (16) to enable night operations and an inverter (17) in ease the pump is to require larger voltages. This would reduce the dependency on electricity from an external grid also remove the need for electrical wiring over a large farm.

[035] Figure 3 shows the system as a whole with separate sources for fertilised water (18) and fresh water (19), connected through single or double pipes as described in the legend, with several instances of the apparatus described before (20) controlling different irrigation zones (21). Optionally, a drainage pipe for excess fertilised water (22) can be installed to ensure any excess fertiliser returns to the treatment station.

Claims

<claim-text>CLAIMS[036] 1 An apparatus for automatically controlling the irrigation and distribution of fertiliscrs into a plantation zone having a dual chamber tank and any shape that allows the control of the flow of both fluids in flexible rates and proportions into a fluid mixer or a fertiliser injector, with the resulting mixture used for irrigation of crops and the automation resulting of any practical process where a programmable controller controls the cycles of distribution of the said resulting mixture into the fields.[037]
2. An apparatus in accordance with claim 1 where thc shape may be manufactured from any suitable material and by any practical process where the finishcd gcometry facilitates the free fallout of fluids by gravity from within.[038]
3. An apparatus in accordance with claims 1 and 2 wherein the cycles of distribution of the said resulting mixture can be activated by the lack of or the presence of moisture in the air or soils in the immediate vicinity.[039]
4. An apparatus in accordance with claims 1 and 2 wherein the cycles of distribution of the said resulting mixture can be activated by the lack of or the presence of sunlight or rain in the immediatc vicinity.[040]
5. A system or method of employing an apparatus in accordance with all previous claims where the control of multiple irrigation zones can be made by any practical connection of these to water and fertiliser sources, in series, in parallel or a combination of both.[041]
6. A system or method of employing an apparatus in accordance with all previous claims powered by solar energy or by any power sources other than solar energy.[042]
7. A system or method of employing an apparatus in accordance with all previous claims where the automation of different irrigation valvcs and pumps in different zones is centralised into one single controller via any wired or non wired connection.[0431 Although the invention has been described in conjunction with specific embodiments thereof; it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art; accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.[044] All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference.Amendments to the claims have been filed as follows.CLAIMS1. An apparatus for automatically controlling the irrigation and distribution of fertilisers into a plantation zone comprising a dual chamber tank, one chamber holding water and the other chamber holding fertiliser, a flow control valve connected at an exit of each chamber, the outputs from the valves being connected at a junction, a static mixer positioned at the junction, a solenoid valve positioned after the mixer, a pressure booster pump positioned after the solenoid valve and a programmable digital timer.</claim-text> <claim-text>2. An apparatus in accordance with claim 1 which is powered by solar electricity.</claim-text> <claim-text>3. Mi apparatus in accordance with claim 1 which is activated by the lack of or the presence of moisture in the air or soils in the immediate vicinity. r</claim-text> <claim-text>4. A system or method of employing an apparatus in accordance with all o previous claims where the control of multiple irrigation zones can be made by any C') practical connection of these to water and fertiliser sources, in series, in parallel or a O combination of both.</claim-text> <claim-text>5. A system or method of employing an apparatus in accordance with all previous claims where the automation of different irrigation valves and pumps in different zones is centralised into one single controller via any wired or non wired connection.</claim-text>