NZ574586A - Irrigation system which applies a predetermined amount of NPK based on application depth and flow rate - Google Patents

Abstract

Disclosed is an automated sprinkler irrigation apparatus (1). The apparatus includes: inlet means (13) connected to an irrigation effluent water source; a manifold (5) connected to the inlet; at least two control valves (3) connected to the manifold; sprinkler means connected to the valves to distribute the irrigation in a predetermined manner; a flow meter (8); and a controller (6). The flow meter provides feedback to the controller of the flow through the valves, and the controller actuates the valves in a sequential cycle so the sprinkler is given a predetermined amount of irrigation. The sprinkler can then deliver a predetermined amount of NPK dependent on effluent application depth and the flow rate, such that dispersion of the water allows absorption of nutrients into a ground surface while reducing run-off.

Description

PATENTS FORM NO. 5 Fee No. 4: $250.00 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional No: 574586 Dated: 30 January 2009 IMPROVEMENTS TO IRRIGATORS FOR WATER AND EFFLUENT APPLICATIONS We, Effluent and Irrigation Design (NZ) Ltd, a New Zealand company of 94J Duke Street, Hamilton, New Zealand hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 Improvements to Irrigators for Water and Effluent Applications TECHNICAL FIELD The present invention relates generally to an automated sprinkler irrigation apparatus, and more particularly to a portable effluent irrigation apparatus.

BACKGROUND ART Dairy effluent produced on a farm is usually collected in storage facilities such as a pond or sump for further application. From there the effluent is pumped to the paddocks and spread using a variety of apparatus and methods. This is called land-based treatment of dairy effluent and is most commonly referred to as 10 'effluent irrigation' or just 'irrigation'. This land-based application is not strictly 'irrigation' in the normal sense as the objective is dispersal of nutrient laden liquid onto paddocks rather than the promotion of growth solely through the application of water.

Low application rate systems for distributing effluent on land (such as the 15 LARALL (low application rate and low labour), IRRIPOD or K-LINE systems) are known. These low application systems are successful in preventing run-off or ponding of the effluent when it is applied to the land primarily through the use of oscillating sprinklers. The sprinklers are specified to apply flow rates that are as low as 3 mm up to 5 mm per hour. The total depth of effluent that is applied on 20 the land is governed by time. For example, if the sprinkler is applying effluent at a rate of 5 mm/hr and was operating for three hours, the total depth would be 15 mm. Over time, such sprinklers also cover the irrigated area with reasonable uniformity. Since effluent is applied at this low rate and manageable depth, nutrients in the effluent are better utilised and the problems with run-off, leaching 25 and ponding on the surface are reduced. 2 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 However, the systems require a number of components (such as pumps, valves and pipe work) to be integrated into the paddock. As such, these systems are complex and therefore may not suit smaller farms (i.e. 400 animals or less).

At present, the most common system used is effluent which is pumped into a 5 mainline system using Poly Vinyl Chloride (PVC) or Medium Density Polyethylene (MDPE) pressure pipe. At measured intervals along the mainline there are paddock hydrants installed to allow connection to a travelling irrigator.

A typical travelling irrigator includes a frame supported on front and rear wheels. A power driven winch is carried on the frame and pulls the unit across a field by 10 reeling in a cable. The cable has one end anchored at one end of a predetermined path of travel (or "cable path") to be followed by the unit. Steering gear attached to the unit guides the forward wheels to follow the cable path. The unit carries a riser pipe for supplying pressured effluent or water to a rotating sprinkler head mounted atop the riser pipe. As the unit travels along the cable 15 path the sprinkler head rotates to distribute either effluent or irrigation water in a predetermined radius around the unit.

Some travelling irrigators carry internal engines to drive the winch. Others use water power reciprocating pistons. Still others drive the winch with a water powered turbine. A transmission is interposed between the winch drive and the 20 drum which reels in cable to provide a range of selectable travel speeds. Travel speed determines the amount of effluent or water applied to a field as the unit moves along a cable path.

One example of a travelling irrigation sprinkler is disclosed in US 4,003,519 which includes a water-powered radial inflow turbine driving a winch that pulls the 25 sprinkler along a path of travel. Water is supplied to a sprinkler gun either directly from an inlet conduit, or indirectly by passing it through the turbine. A 3 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 diverter valve proportions the direct and indirect flows and provides a first means of controlling the travel speed of the sprinkler. A shiftable transmission drivingly interconnects the turbine and winch and provides a second means of controlling travel speed.

In general, the effluent or water is supplied to a travelling irrigator through a long length of flexible hose. Hoses used with travelling irrigators typically have a length within the range of about 150 to 200 metres, and a diameter within the range of about 60 to 120mm. The hose trails along behind the travelling irrigator as the irrigator traverses a cable path. Drag forces imposed on the traveller by 10 the hose help keep the drive cable taut.

The length of a cable path which can be traversed by a travelling irrigator is determined by the length of the supply hose. Cable path length is maximised in usual practice by providing the hose supply header connection near the mid-point of the cable path. During the first half of the travelling irrigator's movement along 15 a cable path, the travelling irrigator moves with the supply header. It then passes by the supply header and moves away from the header during the second half of its movement along the cable path. The maximum cable path length attainable with this system is about twice the length of the supply hose.

Two opposing factors operate to influence the speed of movement of a travelling 20 irrigator is it traverses a cable path. The first is an increase in the effective diameter of the winch drum as more and more cable is wound onto the drum.

This effect tends to increase the speed of travel of the irrigator as more and more cable is reeled in by the winch.

The second factor is increasing drag force load imposed on the travelling irrigator 25 as the length of hose being dragged increases. This factor tends to decrease travel speed as the unit progresses along a cable path. When the travelling 4 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 irrigator is initially positioned at one end of a cable path, the supply hose is laid out behind the irrigator for a distance of 6-10 metres, then makes a wide radius U-turn, and extends forwardly along one side of the path or connection to the supply header. When the travelling irrigator starts moving along the cable path, 5 it must drag only about 6 or 10 metres of water filled hose. However, when the irrigator reaches a midpoint along the cable path, it is then dragging about half the length of the supply hose. As the irrigator approaches the end of the cable path, it is dragging nearly the full length of the supply hose. The range of hose drag force loadings imposed on a travelling irrigator extends from only a few 10 Newtons at the outset of irrigator movement to several thousand Newtons as the irrigator approaches the end of the cable path. A 120 mm diameter water filled hose 200 m long typically imposes about a 24500 Newton force on the irrigator as the irrigator nears the end of the cable path.

From the above, it can be seen that designing a suitable drive system to power 15 the winch of a travelling irrigator poses several problems and as a result these types of apparatus are often unreliable and expensive to manufacture.

Furthermore, a significant disadvantage of a travelling irrigator is their low efficiency as the application rate is too high for effluent application. Specifically, the application rate (speed in which the effluent is sprayed which is measured in 20 mm/hr) and the penetration depth of the land is generally extremely high. The rates and depths can exceed the infiltration rates (penetration depth) of the land.

An excessive application rate can cause ponding and run-off on the surface and can also cause leeching problems in the soil. Leeching occurs when the effluent leeches past the root zone of a plant which means that the nutrients contained in 25 the effluent cannot be utilised by the plant. Nutrients are therefore wasted when the effluent enters aquifers below the soil.

James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 Also, run-off and ponding are major causes of legal breaches by farmers regarding effluent spreading. Over application of effluent can lead to expensive fines and court action imposed by local councils and Government. The poor uniformity (evenness of amount of effluent applied over the whole land or 5 paddock area) by travelling irrigators also contributes to the problem of over application.

From the above, it can be seen that it would be useful if there was a low cost apparatus and method suitable for smaller farms that is able to disperse effluent onto the land at a rate that is within the soil and plant's ability to absorb the 10 nutrients contained within the effluent. Furthermore, it would be useful if the effluent can be spread at a rate that prevents run-off and ponding of effluent which breaches local and Government regulations.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that 15 any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form 20 part of the common general knowledge in the art, in New Zealand or in any other country.

Throughout this specification, the word "comprise", or variations thereof such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements integers or steps, but not the 25 exclusion of any other element, integer or step, or group of elements, integers or steps. 6 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF THE INVENTION According to one aspect of the present invention there is provided an irrigation apparatus including; • an inlet means adapted to be connected to a source of effluent/irrigation water or combination thereof; • a manifold connected to the inlet; • at least one control valve connected to the manifold; • a sprinkler means connected to the control valve, the sprinkler means configured to distribute the effluent/irrigation water in a pre-determined manner about the apparatus; • a flow meter configured to measure the flow of effluent/irrigation water through the control valve; and • a controller wherein the flow meter is configured to provide to the controller feedback of the irrigation water flow rate through the control valve; and wherein the controller is configured to actuate the control valve in a sequential cycle to supply the sprinkler means with a pre-determined amount of effluent/irrigation water over a set time. 7 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 Preferably, at least part of the irrigation apparatus is supported on wheels and includes a tow hitch for portability and transportation of the apparatus.

Preferably, the inlet is connected via an irrigation hose to a paddock hydrant.

Preferably, the apparatus includes a plurality of sprinkler units each connected 5 via a flexible hose attached by a drag hose coupler to the control valve and manifold.

Preferably, the hose is 50-150 metres in length.

More preferably, the apparatus includes six sprinkler units. However, this should not be seen as a limitation on the embodiments envisaged for this invention as 10 any number of sprinkler units could conceivably be used with this invention.

Preferably, the flow meter measures the amount of effluent that passes through each sprinkler unit. This may range from 18 to 20000 litres per hour per sprinkler and may vary dependent on the nozzle size of the sprinkler unit. It is envisaged that after a pre-determined amount of effluent, for example 3500 15 litres, has passed through a sprinkler unit, the controller may close that control valve and open another valve to activate the next sprinkler unit in sequence.

This process is repeated continuously through each of the six sprinklers connected to the control valves.

It is further envisaged that each sprinkler unit may receive substantially the same 20 amount of effluent. For example, based on a 20,000 litre/hour pumping volume the amount distributed onto the ground would penetrate a depth of approximately 1.5 mm at an application rate no more than 7 mm/hour.

According to another aspect of the present invention there is provided a method for applying effluent/irrigation water including the steps of: 8 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 1. supplying a source of effluent/irrigation water or combination thereof to at least one sprinkler means connected to at least one control valve for distributing the effluent/irrigation water in a pre-determined manner about the sprinkler means; 2. measuring the amount of effluent/irrigation water that flows through the at least one sprinkler means; and 3. actuating a control valve via a controller on a sequential cycle to supply the at least one sprinkler means with a pre-determined amount of effluent/irrigation water over a set time.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 shows a diagrammatic representation of a plan view of an effluent 15 irrigation apparatus of the present invention; Figure 2 shows a diagrammatic representation of a side view of the same effluent irrigation apparatus of Figure 1; Figure 3 shows a diagrammatic representation of a plan view of the same effluent irrigation apparatus of Figures 1 and 2 in use with 20 sprinkler units; and Figure 4 shows a diagrammatic representation of a plan view of an optional embodiment of the present invention - a slave bank of valves. 9 James & Wells Ref: 234513/61 EH Received at IP0NZ 20 May 2011 DETAILED DESCRSPTSON INCLUDING BEST MODES The purpose of the effluent irrigation apparatus is to disperse effluent onto the ground at a rate that is within the soil's ability to absorb the nutrients. It is envisaged that the effluent is spread at a rate and depth in which the plant can 5 utilise a large percentage of nutrients. Because of the rate at which the effluent is applied, the effluent irrigation apparatus will reduce run-off and ponding.

In preferred embodiments of the present invention the effluent may be mostly dairy effluent. However, it should be appreciated by those skilled in the art that the apparatus can be utilised to disperse any type of waste such as pig effluent 10 and other such animal effluent.

Apparatus and Set-up With reference to Figures 1 to 3, an exemplary portable irrigation apparatus generally indicated at (1) is illustrated.

The apparatus (1) consists of multiple portable sprinkler units (2, shown in Figure 15 3), each connected to a control valve (3) by a flexible hose (4, shown in Figure 3) (50-150 metres long) to a valve manifold (5).

The manifold (5) includes a controller (6) housed in a stainless steel box with a battery to allow individual control of the sprinkler units (2). The manifold (5) also incorporates an in-line filter (7, shown in Figure 2) with a flow meter (8) to 20 measure actual flow rate and amount of effluent supplied to each sprinkler unit (2). The controller (6) actuates the control valves (3) on a sequential basis and the flow meter (8) provides feedback of the effluent flow rate to allow the system to supply each sprinkler unit (2) with a predetermined, or equal, amount of effluent.

James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 The manifold (5) is also portable and mounted onto a built in trailer unit (9) with tow hitch (12) to allow the whole apparatus (1) to be moved, preferably between a series of paddock hydrants (10, shown in Figure 3) connected to an underground effluent supply network (11, shown in Figure 3).

Figure 3 shows the portable irrigation apparatus (1) in use connected to a paddock hydrant (10) wherein effluent is pumped through the inlet (13) of the portable irrigation apparatus (1) and exits via a series of sprinkler units (2).

In a preferred embodiment a typical set up may include six sprinkler units (2) placed apart in a single paddock in a given application area (14) such as position 10 1 or 2 (shown in Figure 3) which are connected to corresponding control valves (3) via drag hose couplers (15) to 63 mm MDPE drag hose (4).

It should also be appreciated by those skilled in the art that other types of hose including lay flat hose can be conceivably used with this invention. The lengths of drag hose may vary from 50-150 metres. The applicant has found that using 15 63mm MDPE drag hose (4) of greater length than 150 metres causes the pressure to be too low at the sprinkler unit (2). This affects operation within the required guidelines to achieve the desired application rate as described below.

A flow meter (8) integrated into the manifold (5) measures the flow rate of the effluent, and provides these measurements to a controller (6) mounted to the 20 manifold (5) of the irrigation apparatus (1). The controller is programmed such that once a pre-determined amount of effluent has passed through the flow meter (8) (which corresponds to the amount received by the measured sprinkler unit (2)) one of the control valves (3) will be closed and another control valve (3) will subsequently be opened to activate another sprinkler unit (2) connected in 25 series. This operation is described in more detail below.

A typical amount of effluent that may be applied to a paddock is 3,000 litres over 11 Received at IPONZ 20 May 2011 James & Wells Ref: 234513/61 EH an area of approximately 2,000 m2. This process is repeated continually through each of the six valves (3), such that each sprinkler (2) will receive the same amount of effluent. Based on a 20,000 litre/hour pumping volume, the amount applied or sprayed onto the ground may be approximately 1.5mm (total depth) 5 with an application rate of 9mm/hour.

Operation of the Apparatus Referring to Figure 3 the portable irrigation apparatus (1) is towed into a paddock that requires effluent application and detached from the vehicle (not shown). The sprinkler units (2) are positioned around the paddock or application area (14) 10 in known fashion to ensure even distribution of effluent from the apparatus. See for example position 1 (14A) and position 2 (14B) in application area (14) of Figure 3.

The portable irrigation apparatus (1) receives effluent from an effluent supply network (11) via a flexible hose (16) from a paddock bridge hydrant (10) 15 connected to a pumping system. From the hydrant (10), the portable irrigation apparatus (1) is connected using a 50 mm flexible hose (16) through the inlet (13).

Typical hydrants that may be used for this invention include ECOSTREAM and HI-TECH HYDRANTS. These are only two examples of hydrants that can 20 conceivably be used for this invention. Other hydrants may include any hydrant manufactured for lay flat hose and couplers.

The effluent passes through the inlet manifold and is directed to one of the sprinkler units (2) via the corresponding control valve (pressure assisted) (3) and 63 mm drag hose (4).

Typical valves that may be used for this invention include water assisted, electric 12 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 conceivably be used for this invention and should not be seen as limiting.

In preferred embodiments water assisted valves are fed by an independent water supply on the hydrant. The water may be stored in a reservoir. It is envisaged that a pressure pump pumps the water into a pressure tank so the pressure is 5 greater than the effluent/water which enters the hydrant.

In preferred embodiments the valves may be controlled by a PLC in the control box. Preferably, the control box is manufactured out of plastic. However other materials such as stainless steel could conceivably be used with this invention.

Preferably, the valves discharge is directed back into the water reservoir. It is 10 further envisaged the apparatus includes a pressure sensor that detects the incoming effluent/water and turns on the PLC. If the pressure drops the PLC will turn off the hydrant.

More particularly, the control valves (3) are controlled to operate one at a time by a PLC controller (6). The controller (6) receives a feedback signal from the flow 15 meter (8) (proportional to the rate of flow of the effluent, for example from 3-5 metres/second). Once the pre-determined amount of effluent has passed through the flow meter (8) (for example 3,000 litres), the PLC controller (6) will shut off the open control valve (3) and open the next control valve (3) in sequence which activates another sprinkler unit (2) connected in series. The 20 amount of effluent applied to a paddock may be varied according to purpose and may range from 2,000-4,000 litres.

The amount of effluent applied to a paddock will be governed by the water holding capacity of the soil at the time of irrigation. The more capacity available, the more effluent that can be applied to the paddock.

In preferred embodiments the time of operation may be a 60 minute cycle which 13 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 includes each sprinkler unit receiving 10 minutes of effluent and a 50 minute stand down period whereby no effluent is received. The advantage of this cycle of operation is that it allows the effluent to penetrate the soil efficiently.

The PLC controller (6) automatically operates one control valve (3) after another 5 and is configured to receive feedback from the flow meter (8) which measures the flow with the measurement being sent to the controller (6). This reflects the amount of effluent that is sent to the current operating valve (3) and related sprinkler unit (2) based on measurements provided by the flow meter (8) (for example, a pre-set time or flow rate set by a PLC). Once a pre-set amount of 10 effluent (for example 3,000 litres over a 10 minute period), is measured to have passed through the control valve (3) (and related sprinkler (2)), the controller (6) shuts down the control valve (3) and opens the next control valve (3) and subsequent sprinkler unit (2) in sequence.

The controller (6) will keep running through this sequence repeatedly until all 15 sprinkler units (2) have applied effluent. This gives the soil the opportunity to periodically absorb small amounts of effluent rather than the typical large amount 'dumped' on in a single application as with prior art higher volume systems. A large 'dumping' of effluent ends up running off through the surface and directly down through the soil profile and away from the feeder-root zone of plants.

Preferably, if the flow of effluent stops (for example, if the paddock hydrant pump has been turned off), the controller (6) keeps the control valve (3) open and waits for flow to return so that it can continue with that control valve (3) and related sprinkler unit (2) until it has received the set or pre-determined amount of effluent. The advantage of this mechanism is that it allows each sprinkler unit to 25 receive the same amount of effluent even if the pumping cycle has been interrupted. This is performed automatically according to the level of the effluent source. For example, the pump may stop half way through a sprinkler cycle if 14 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 the effluent in the pond has been emptied.

In preferred embodiments the controller (6) is able to monitor the total amount of effluent applied by each sprinkler unit (2) so that the pump can be automatically switched off and/or an operator is able to determine when the apparatus and/or sprinkler units require moving to another position or next paddock.

Preferably, the portable irrigation apparatus (1) may also be equipped with a Global Positioning System (GPS) or communication device such as a modem. These systems/devices enable an operator and/or the controller (6) to keep track of the history and location of the irrigation apparatus in a paddock or across a series of paddocks. For example, the system may be configured to record the location(s) and amount of effluent applied in each location and to de-activate the apparatus if a user attempts to over-apply effluent in a particular location. The advantage of such safeguard is that it allows the nutrients to be absorbed into the paddock without over application of effluent. However, it is envisaged that the GPS may be manually over ridden with a lock code or equivalent if desired.

It is also envisaged that the apparatus may include a display or simply a warning light or siren, or may send an SMS, email or fax message to the operator when a pre-set total limit is approached/reached.

Preferably, a warning light may flash slowly as it approaches the set limit with an increasing rate of flashing nearing completion and finally a solid light indicating the pre-set limited has been reached.

It is further envisaged that the parameters of the controller (6) may be set to limit the application of effluent to 15 mm in soil depth penetration over one pumping cycle. For example, if the amount of effluent applied over a one hour pumping cycle is 1.5 mm per sprinkler unit (2), then the pump will be set to operate for a total of 10 hours. If the amount of effluent applied per sprinkler unit (2) is 3,300 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 litres to achieve the 1.5 mm depth, then the PLC controller (6) can be programmed to shut off all flow once the total volume applied per sprinkler unit (2) reaches 33,000 litres.

In preferred embodiments the total application depth is governed by the NPK 5 levels in the effluent. For example, effluent with a nitrogen nutrient value of 0.3 will deliver the equivalent of 30 kilograms of nitrogen if dispersed at a 10 mm depth penetration into a paddock. It is envisaged that the controller may be configured so that, after analysis of an effluent sample to determine its NPK levels, a particular nutrient value may be selected (for example 30 kg nitrogen) 10 and the system will automatically deliver the desired amount, and then notify the operator and/or automatically switch the pump off as previously described.

In preferred embodiments the controller (6) may be programmed to include only one pre-set amount of effluent that all control valves (3) and related sprinkler units (2) receive before closing and activating the next valve in sequence. 15 However, this should not be seen as a limitation on the embodiments envisaged for this invention as each control valve (3) may be assigned individual amounts of effluent to be applied. For example, there may be a need to program and adjust the individual amounts of effluent to be applied for each valve. This program may be useful in situations where a paddock has a varying slope such that flatter 20 parts of the paddock will receive higher amounts of animal waste (dung and urine) than sloping areas. Therefore, tailoring the amount of effluent applied to individual areas can rectify this imbalance in naturally applied fertilizer produced by animals. Also, depending on drainage and soil composition some parts of a paddock require (or can take) a higher nutrient load than other parts and so can 25 take larger amounts of effluent application.

It is further envisaged that the apparatus may use a "slave" bank of remote valves that are remotely controlled by a radio signal from the main controller. 16 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 The slave bank of remote values may be fed with effluent via a flexible hose between these valves and the main apparatus manifold. The slave bank may be utilised for narrow paddocks approximately 400 metres or longer. In particular, Figure 4 shows a set of two valves (3) which may be connected by a flexible pipe 5 (such as 65 mm lay flat hose, not shown) to the apparatus (1) (Figures 1 and 2) which are then operated by radio frequency from the main unit. Other components such as separate controller (6), filter (7) and battery (17) are also shown. The slave bank of valves (9) practically extends the manifold to a length of 100-200 metres allowing shorter sprinkler hoses to be used and which can still reach remote areas of a paddock.

There are many advantages associated with this invention; • The portable irrigation apparatus is able to disperse effluent onto the ground at a rate which is within the soil's ability to absorb the nutrients.

• The use of this irrigation apparatus prevents excess application of effluent. Excess application of effluent leads to ponding and run-off of effluent into natural waterways which can breach national and regional bylaws.

• The apparatus and method utilises a supply network that is capable of supplying one sprinkler unit at a time combined with the ability to automatically apply effluent to multiple sprinkler units in each cycle. This dramatically increases the coverage area. Once enough effluent has been applied by each sprinkler unit, each sprinkler is able to be easily moved to another position on the same paddock and the process can start again.

• A further advantage of this invention is that once the whole paddock has been covered, the entire apparatus is transportable enabling it to be 17 James & Wells Ref: 234513/61 EH Received at IPONZ 20 May 2011 easily relocated and set up to operate on the next paddock requiring effluent application. Other prior art low application rate systems are integrated into the paddock and cannot be easily relocated.

Aspects of the present invention have been described by way of example only 5 and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims. 18 Received at IPONZ 20 May 2011

Claims (15)

WHAT WE CLAIM IS:

1. An irrigation apparatus including; • an inlet means adapted to be connected to a source of effluent/irrigation water or combination thereof; • a manifold connected to the inlet; • at least two control valves connected to the manifold; • a sprinkler means connected to the control valves, the sprinkler means configured to distribute the effluent/irrigation water in a pre-determined manner about the apparatus; • a flow meter configured to measure the flow rate of effluent/irrigation water through the control valves; and • a controller wherein the flow meter is configured to provide to the controller feedback of the irrigation water flow rate through the control valves; and wherein the controller is programmed to actuate the control valves in a sequential cycle to supply the sprinkler means with a pre-determined amount. of effluent/irrigation water to deliver a pre-determined amount of NPK dependent on effluent application depth and the flow rate of effluent/irrigation water such that dispersion of the effluent/irrigation water allows absorption of nutrients into a ground surface while reducing run-off.

2. An irrigation apparatus as claimed in claim 1, wherein the inlet is connected via an irrigation hose to a paddock hydrant. 19 Received at IPONZ 20 May 2011

3. An irrigation apparatus as claimed in claim 1 or claim 2, wherein the apparatus includes a plurality of sprinkler means.

4. An irrigation apparatus as claimed in claim 3, wherein the sprinkler means are connected via a flexible hose attached by a drag hose coupler to the control valves and manifold.

5. An irrigation apparatus as claimed in any one of claims 1 to 4, wherein the hose is 50-150 metres in length.

6. An irrigation apparatus as claimed in claim 4 or claim 5, wherein the hose is 63 mm medium density polyethylene (MDPE) pressure pipe.

7. An irrigation apparatus as claimed in any one of claims 3 to 6, wherein the flow meter is configured to measure the amount of effluent/irrigation water that passes through each sprinkler means and the controller is programmed so that each sprinkler means receives substantially the same amount of effluent/irrigation water during a full sequential cycle.

8. An irrigation apparatus as claimed in claim 7, wherein the pre-determined amount of effluent received per sprinkler means is between 2000 to 4000 litres.

9. An irrigation apparatus as claimed in any one of claims 1 to 8, wherein the apparatus includes a Global Positioning System (GPS).

10. An irrigation apparatus as claimed in any one of claims 1 to 9, wherein the apparatus includes a display or a warning system to alert an operator when a pre-set total limit of effluent/irrigation water is approached/reached. 20 Received at IPONZ 20 May 2011

11. An irrigation apparatus as claimed In claim 10, wherein the warning system includes a SMS, email or fax message to alert the operator when the pre-set total limit effluent/irrigation water is approached/reached.

12. An irrigation apparatus as claimed in any one of claims 1 to 11, wherein the apparatus includes a slave bank of remote valves that are remotely controlled by a radio signal from the controller.

13. An irrigation apparatus as claimed in any one of claims 1 to 12, wherein at least part of the apparatus is supported on wheels.

14 An irrigation apparatus as claimed in any one of claims 1 to 13 wherein the apparatus includes a tow hitch.

15. A method for applying effluent/irrigation water including the steps of: (a) measuring an NPK concentration in the effluent/irrigation water; (b) utilising the NPK concentration in step (a) to provide an effluent application depth; (c) supplying a source of effluent/irrigation water or combination thereof to a sprinkler means connected to at least two control valves for distributing the effluent/irrigation water in a pre-determined manner about the sprinkler means; and (d) measuring a flow rate of effluent/irrigation water that flows through the sprinkler means; wherein the controller is programmed to actuate the control valves on a sequential cycle to supply the at least one sprinkler means with a predetermined amount of effluent/irrigation water to deliver a predetermined amount of NPK dependent on the effluent application depth 21 Received at IPONZ 20 May 2011 in step (b) and the flow rate in step (d) such that dispersion of the effluent/irrigation water allows absorption of nutrients into a ground surface while reducing run-off. A method for applying effluent/irrigation as claimed in claim 15, wherein the amount of effluent/irrigation water that flows through each sprinkler unit is 20,000 litre/hour. A method for applying effluent/irrigation as claimed in claim 15, wherein the amount applied or sprayed onto ground about the apparatus is 1.5 mm (total ground penetration depth) including an application rate of 9rmm/hour. A method for applying effluent/irrigation as claimed in any one of claims 15 to 17, wherein the control valves are controlled to operate one at a time by a PLC controller. A method for applying effluent/irrigation as claimed in claim 18, wherein the PLC controller receives a feedback signal from a flow meter proportional to the rate of flow of the effluent. A method for applying effluent/irrigation as claimed in claim 18 or claim 19, wherein once a pre-determined amount of effluent has passed through the flow meter, the PLC controller shuts off the open control valve and opens the next control valve in sequence which activates another sprinkler unit connected in series. A method for applying effluent/irrigation as claimed in claim 20, wherein the controller maintains this sequence repeatedly until all sprinkler units have applied effluent. A method for applying effluent/irrigation as claimed in any one of claims 15 to 21, wherein if pumping of effluent stops, the controller keeps the actuated 22 Received at IPONZ 20 May 2011 control valve open and waits for flow to return so that it can continue with that control valve and related sprinkler unit until it has received the set or predetermined amount of effluent. A method for applying effluent/irrigation as claimed in any one of claims 15 to 22, wherein the time of operation of the apparatus is a 60 minute cycle which includes each sprinkler unit receiving 10 minutes of effluent and a 50 minute stand down period whereby no effluent is received. A method for applying effluent/irrigation as claimed in any one of claims 15 to 23, wherein the controller is able to monitor the total amount of effluent applied by each sprinkler unit. A method for applying effluent/irrigation as claimed in any one of claims 15 to 24, wherein the controller is programmed to include only one pre-set amount of effluent that all control valves and related sprinkler units receive before closing and activating the next valve sequence. A method for applying effluent/irrigation as claimed in any one of claims 15 to 25, wherein parameters of the controller are set to limit the application of soil depth penetration of effluent to 15 mm over one pumping cycle. An irrigation apparatus substantially as herein described with reference to and as illustrated by the accompanying drawings. A method for applying effluent/irrigation substantially as herein described with reference to and as illustrated by the accompanying drawings. Effluent & Irrigation Design (NZ) Ltd By their Attorneys James & Wells Intellectual Property 23