System and arrangement for plant irrigation

Abstract

System (1) for plant irrigation, comprising a liquid reservoir (2) that can be arranged in the ground (ER) and at least one capillary line (3) that can be coupled to the liquid reservoir (2) and which is configured to convey, in a state coupled to the liquid reservoir (2), a liquid stored in the liquid reservoir (2) by capillary action into the root zone (WB) of a plant (PF) arranged above the liquid reservoir (2).

Description

[0001] The present invention relates to a system for plant irrigation and an arrangement comprising such a system in a state arranged in the ground and a plant planted above it.

[0002] In urban areas with high levels of surface sealing, reliable irrigation of larger plants such as trees is difficult to achieve. Often, rainwater falling on the sealed surface is diverted into a sewer system and is therefore unavailable for plant irrigation.

[0003] Conventional systems for plant irrigation are known, for example, from DE 20 2017 003 834 U1 or DE 36 33 390 A1.

[0004] The present invention is based on the objective of remedying this problem and providing a system and arrangement for plant irrigation with which reliable irrigation of plants can be ensured, particularly in urban areas with high surface sealing.

[0005] To solve this problem, the present invention provides the system according to claim 1 and the arrangement according to claim 10.

[0006] A plant irrigation system is disclosed, comprising a liquid reservoir that can be arranged in the ground and at least one capillary tube that can be coupled to the liquid reservoir and is configured to direct, in a state coupled to the liquid reservoir, a liquid stored in the liquid reservoir by capillary action into the root zone of a plant arranged above the liquid reservoir.

[0007] The liquid reservoir can be positioned directly beneath the plant to be irrigated and therefore requires no separate installation space. A coupled state is a state in which the capillary tube can transport liquid from the reservoir to the root zone of a plant positioned above the reservoir. A lower end of the capillary tube preferably extends into the reservoir. An upper end of the capillary tube preferably protrudes above the reservoir. Preferably, more than half the length of the capillary tube lies outside the reservoir. A lower end of the capillary tube is preferably located at the lowest point of the reservoir, so that the reservoir's storage volume can be utilized as completely as possible for plant irrigation.These two elements, liquid storage and capillary tube, allow for the provision of an effective plant irrigation system in a limited space, particularly for urban areas with high surface sealing.

[0008] Advantageous embodiments of the invention are the subject of the dependent claims.

[0009] It can be advantageous if the liquid reservoir has a water-permeable, preferably grid-shaped housing and / or (within the housing) a trough- or channel-shaped liquid collection section. This allows the liquid reservoir to directly absorb precipitation falling on the planting area or excess water from irrigation and return it to the plant for irrigation via capillary action.

[0010] The fluid storage system can comprise multiple connectable storage modules. The storage modules are preferably identical and preferably arranged regularly and / or symmetrically to one another. An example of a storage module is a polymer storage box or trench, e.g., of type SX.

[0011] The liquid reservoir can be designed to prevent surrounding soil from entering the storage volume. This ensures that the liquid storage volume remains constant even over extended periods.

[0012] The liquid storage tank can include an inlet through which it is fed with surface water. This allows a larger catchment area of ​​rainwater to be used for irrigating the plant.

[0013] The liquid storage system may include a drain through which liquid is released when a maximum storage volume is exceeded, preferably into the surrounding soil or a canal system.

[0014] It can be useful if the system includes a plurality of capillary tubes, which are preferably identical in design and preferably configured to be arranged regularly and / or symmetrically with respect to the fluid reservoir.

[0015] It can prove practical if the capillary line, for example, comprises a tube which forms a wall of the capillary line, the tube preferably being made of plastic, preferably of polypropylene.

[0016] The diameter of the tube is, for example, in the range of 50 to 300 mm, preferably in the range of 80 to 150 mm, more preferably in the range of 100 to 120 mm, and most preferably in the range of 110 mm.

[0017] The length of the pipe is, for example, in the range of 300 to 5,000 mm, preferably in the range of 500 to 2,000 mm, preferably in the range of 750 to 1,000 mm, and most preferably in the range of 900 mm.

[0018] It is also within the scope of the invention that the capillary tube, viewed in cross-section, is shaped approximately prismatic, polygonal, oval, and the like.

[0019] It can be advantageous if the capillary tube has a wall that is at least partially permeable to water, in particular perforated, wherein the wall preferably comprises a plurality of openings which are preferably aligned at regular intervals along a line extending parallel to the axis of the tube.

[0020] The diameter of each opening is, for example, in the range of 2 to 60 mm, preferably in the range of 4 to 50 mm, preferably in the range of 5 to 45 mm, and most preferably in the range of 6 mm.

[0021] The distance between two openings (for example, from center to center) is, for example, in the range of 20 to 200 mm, preferably in the range of 50 to 150 mm, more preferably in the range of 80 to 120 mm, and most preferably in the range of 100 mm.

[0022] It can be advantageous for the capillary tube to have a water-permeable filter, preferably on the inside of a wall and / or at one or both ends of the tube, wherein the filter is preferably a nonwoven fabric made of plastic, preferably polyolefin, preferably PP. The filter preferably serves to allow liquid to enter the capillary tube, to prevent soil from entering the tube, and to prevent any filler material contained within the capillary tube from escaping.

[0023] The thickness of the nonwoven fabric (mean values ​​according to DIN EN ISO 9863:2020-04), especially at a load of 2 kPa, is preferably in the range between 0.2 and 5 mm, preferably in the range between 0.5 and 2.5 mm, preferably in the range between 1.0 and 1.5 mm, and most preferably at 1.2 mm.

[0024] The basis weight of the nonwoven fabric (average values ​​according to EN ISO 9864:2005) is preferably in the range between 50 and 250 g / m². 2 preferably in the range between 100 and 200 g / m² 2 , particularly preferably in the range between 125 and 175 g / m³, and most preferably at 150 g / m³ 2 .

[0025] The puncture resistance of the nonwoven fabric (mean values ​​according to DIN EN ISO 12236:2006-11) is preferably in the range between 0.2 and 5 kN, preferably in the range between 1 and 3 kN, preferably in the range between 1.5 and 2.5 kN, and most preferably at 2 kN.

[0026] The water permeability of the fleece (mean values ​​according to DIN EN ISO 11058:2019-09) is preferably in the range between 0.01 and 1 m / s, preferably in the range between 0.05 and 0.5 m / s, preferably in the range between 0.08 and 0.2 m / s, and most preferably at 0.1 m / s.

[0027] It can be useful if the capillary tube includes a capillary filler, wherein the filler is preferably a fine-grained, preferably mineral bulk material, such as quartz flour, particularly preferably with a maximum grain size of 250 µm.

[0028] Furthermore, it can be useful if the capillary line includes a capillary filler, wherein the filler is preferably a fine-grained, preferably mineral bulk material, such as quartz flour, that the capillary line has a capillary filler such as quartz flour, with a high proportion of about 49% fine particles with a particle size of less than 63 µm.

[0029] An example of a suitable filler is Millisil W4 quartz flour of the grain size group 0 / 0.25. However, any other filler with comparable capillary properties is also suitable, e.g. thin tubes.

[0030] It can be advantageous if the capillary line has a capillary suction height that is approximately as large as the length of the capillary line and / or at least as large as the height of the liquid reservoir, preferably measured from the lowest point of the liquid reservoir or the liquid collection section.

[0031] The capillary suction height is preferably in the range of 0.3 to 2 m, more preferably 0.5 to 1.2 m, more preferably 0.8 to 1.0 m. With this capillary suction height, ideal irrigation of the plant from the underlying liquid reservoir can be achieved.

[0032] Another aspect of the present invention relates to an arrangement comprising a system according to one of the preceding embodiments, wherein at least one liquid reservoir is arranged in the ground and the at least one capillary tube is coupled to the liquid reservoir in such a way that it directs a liquid stored in the liquid reservoir by capillary action into the root area of ​​a plant arranged above the liquid reservoir.

[0033] The lower edge of the liquid storage tank is located, for example, at a depth of 0.5 to 3 m, preferably at a depth of 0.8 to 2 m, preferably at a depth of 1 to 1.5 m, measured from the surface of the overlying soil.

[0034] The liquid storage unit has, for example, a substantially prismatic, rectangular, or square outline. The edge length of this rectangular or square outline is, for example, in the range of 1 to 5 m, preferably in the range of 2 to 3 m, and more preferably in the range of 2.2 to 2.8 m.

[0035] The liquid storage system includes, for example, a liquid storage volume in the range of 0.5 to 10 m³. 3 , preferably in the range of 1 to 5 m 3 , preferably in the range of 1.5 to 3 m 3 , especially preferably from about 2 m 3 .

[0036] The root area / trunk of the plant to be irrigated is preferably arranged centrally (in top view) with respect to the outline of the liquid reservoir. The offset between the root area / trunk of the plant to be irrigated and the center point / centroid of the liquid reservoir (in top view) is preferably less than 1 m, preferably less than 0.8 m, and most preferably less than 0.5 m.

[0037] The at least one capillary tube is preferably arranged centrally with respect to the outline of the liquid reservoir. The offset between the at least one capillary tube and the center point / centroid of the liquid reservoir (in plan view) is preferably less than 1 m, preferably less than 0.8 m, and most preferably less than 0.5 m.

[0038] The at least one capillary tube preferably projects exactly or substantially vertically above the liquid reservoir, preferably starting from a lowest point of the liquid reservoir, preferably a trough-shaped or channel-shaped liquid collection section.

[0039] The arrangement can comprise multiple capillary tubes. The multiple capillary tubes are preferably identical and preferably arranged regularly and / or symmetrically with respect to the fluid reservoir. This ensures that the root area is supplied with sufficient water evenly from all sides.

[0040] It can be advantageous if the liquid storage system comprises multiple communicating storage modules, the storage modules preferably being identical and preferably arranged regularly and / or symmetrically to one another. Identical storage modules simplify manufacturing. The modular design of the liquid storage system facilitates the transport of the modules and their arrangement, for example, in the ground. The regular and / or symmetrical arrangement of the modules promotes the uniform distribution of liquid and the even irrigation of the plant being watered. Terms and definitions Capillary effect

[0041] Capillary action occurs when the interface of a liquid is located in a capillary or crevice of a solid. This interface lies between a liquid and a second fluid phase, such as a gas or another liquid that is immiscible with the first.

[0042] The capillary effect is determined by the surface tension of the liquid (cohesion) and the interfacial tension between the liquid and the solid surface (adhesion), or the wettability of the solid surface with the liquid.

[0043] The capillary suction height or rise height h of a liquid column is determined by the equation: h=2σ cos θ / (ρ gr)

[0044] This includes: σ = Surface tension θ = contact angle ρ = density of the liquid g = acceleration due to gravity r = radius of the tube

[0045] A capillary filler is a filler that creates a capillary effect through the surface tension of the water (cohesion) and the interfacial tension between the water and the solid surface of the filler (adhesion). This capillary filler allows the water in the liquid reservoir to rise to the desired height in the root zone of the plant being irrigated.

[0046] An example of such a capillary filler is quartz flour Millisil W4 of the grain size group 0 / 0.25. In this capillary filler, the capillaries do not form ideal tubes, but rather randomly shaped spaces, so the above formula can only be used approximately to calculate the capillary suction height or rise height h.

[0047] For a fine-grained bulk material such as quartz flour with maximum grain sizes of 0.25 mm, a capillary suction height or rise height of approximately 1 m results.

[0048] The exact value can be determined through experimentation. The capillary suction height or rise height h tends to increase with decreasing particle size. Brief description of the characters

[0049] They show: Fig. 1: a section II through the arrangement according to Fig. 2, comprising a plant irrigation system according to the invention with a liquid reservoir and four capillary tubes (“wicks”) protruding from the liquid reservoir. Fig. 2: a (simplified) top view (without plant) of a plant irrigation arrangement with a liquid inlet and a liquid outlet. Fig. 3: a capillary line of the system according to the invention for plant irrigation in the form of a perforated plastic pipe, which is lined on the inside with separation and filter fleece and filled with quartz flour as capillary filler, wherein view (a) shows the capillary line from the side and view (b) shows the capillary line in a section through the line axis. Detailed description of preferred embodiments

[0050] The present invention relates to a system 1 and an arrangement for plant irrigation, which comprises a liquid storage tank 2 in the form of several connected infiltration boxes (trenchs) and four capillary lines 3 protruding from the liquid storage tank 2 in order to direct a liquid stored in the liquid storage tank 2 by means of capillary action into the root zone WB of a plant PF arranged in the soil ER above the liquid storage tank 2.

[0051] As in Fig. 1 and Fig. As shown in Figure 2, the liquid storage system 2 is composed of a total of nine storage modules and is located in the ground ER.

[0052] The lower edge of the liquid storage tank 2 is located at a depth of approximately 1.5 m below the surface of the overlying soil ER.

[0053] The storage modules are cuboid-shaped drainage boxes made of plastic (PP), each with a grid-like housing and a trough- or channel-shaped liquid collection section inside the housing.

[0054] Examples of storage modules are infiltration boxes (trench trenches) of type SX with a length and width of 0.8 m each and a height of approximately 0.4 m and a liquid storage volume of approximately 230 liters each.

[0055] The storage modules are, for example, arranged end-to-end in three rows and three columns to form a communicating fluid storage unit 2 with an approximately square outline of about 2.4 m sides and a height of about 1 m. The storage modules can also be arranged in multiple layers (three-dimensionally) to increase the storage volume.

[0056] In contrast to the storage modules in the lowest level, the storage modules in higher levels preferably do not include a trough- or channel-shaped liquid collection section.

[0057] The edge length of liquid reservoir 2 corresponds approximately to the crown diameter of the plant PF to be irrigated when fully grown. The combined storage volume of the entire liquid reservoir 2 is approximately 2 m³. 3 .

[0058] Liquid storage tank 2 is filled with rainwater.

[0059] This includes, on the one hand, the rainwater, which penetrates directly into the soil ER located above the liquid storage tank 2 and seeps away there until it reaches the liquid storage tank 2 and there passes through the grid-like housing into the trough- or channel-shaped liquid collection section.

[0060] For larger trees with a seed diameter exceeding 3 m, this small area is insufficient to ensure an adequate water supply during prolonged dry periods. Therefore, the liquid storage tank 2 is connected to a channel system that collects rainwater from surrounding sealed surface areas and feeds it to the liquid storage tank 2 via an inlet 4.

[0061] The inlet 4 includes inlet pipes 4a, 4c and an intermediate shaft 4b to regulate the amount of precipitation supplied to the liquid storage tank 2 to an ideal fill level of the liquid storage tank 2.

[0062] To avoid overfilling the liquid reservoir 2 and waterlogging in the root area WB of the plant PF to be irrigated, the liquid reservoir 2 is connected to a drain 5.

[0063] With outlet 5, liquid from the liquid storage tank 2 can be drained after exceeding an overflow threshold via outlet pipes 5a, 5c and an intermediate shaft 5b.

[0064] When the overflow threshold is exceeded, the liquid can also run over the edge of the storage section and seep directly into the soil ER lying below the liquid storage 2.

[0065] Piping systems for inlet 4 and outlet 5 are usually laid at depths of 1 to 1.5 m.

[0066] To connect liquid storage tank 2 to inlet 4 and outlet 5 as easily as possible, plant PF can be planted in an enclosed and raised area. The upper edge of this area is approximately 0.5 m above the level of the surrounding surface seal, and its square outline, with an edge length of approximately 2.8 m, is slightly larger than the square outline of liquid storage tank 2. The upper edge of liquid storage tank 2 is roughly at the level of the surrounding surface seal or even slightly above it.

[0067] Capillary line 3 is described below with reference to the Fig. 3 described in detail.

[0068] Each capillary tube 3, which can also be called a wick due to its capillary action, comprises a sectionally water-permeable wall (jacket) 3a, e.g. a perforated PP plastic pipe DN 110 mm.

[0069] The nominal diameter of pipe 3a is 110 mm and the length is 900 mm.

[0070] The dimensions of the capillary tube 3 are important for determining the capillary effect in order to direct sufficient quantities of water from the liquid reservoir 2 to the root zone WB of the plant PF to be irrigated.

[0071] To allow the ingress of liquid, the capillary tube 3 is provided with boreholes 3d of 15 mm diameter at regular intervals L3d of 100 mm along a line extending parallel to the tube axis X3.

[0072] Several rows of such boreholes 3d can be provided distributed around the perimeter of the wall 3a, ideally at regular angular intervals around the axis X3 of the capillary tube 3, for example four rows of boreholes 3d each aligned parallel to the axis X3 of the capillary tube 3 at angular intervals of 90°.

[0073] The capillary tube 3 is lined on the inside and at both ends with a separation and filter fleece 3b to allow liquid from the liquid reservoir 2 to enter the capillary tube 3, to prevent soil ER from entering the capillary tube 3 and to prevent filler material 3c from escaping the capillary tube 3.

[0074] A suitable separation and filter fleece 3b is a plastic fleece (PP) of type RAUMAT 3E 150, which is specially designed for use in rainwater management and is characterized by its high flexibility.

[0075] Advantageous properties of an exemplary separation and filter fleece 3b are: - Thickness (average value according to EN ISO 9863) at 2 kPa: 1.2 mm - Basis weight (average value according to EN ISO 9864): 150 g / m² 2 - Punch penetration force (average value according to DIN EN ISO 12236): 2 kN - Water permeability (average value according to EN ISO 11058) 0.1 m / s

[0076] To create the capillary effect, the capillary tube 3 is filled with a fine-grained mineral filler with grain sizes up to 250 µm.

[0077] The capillary line 3 comprises a capillary filler, wherein the filler is preferably a fine-grained, preferably mineral bulk material, such as quartz flour, wherein the capillary line 3 has a capillary filler such as quartz flour, with a high proportion of about 49% fine particles with a particle size of less than 63 µm.

[0078] A suitable filler 3c is, for example, quartz flour of type Millisil W4 with a particle size distribution of 0 / 0.25. This means that 100% (by weight) of the particles pass through a sieve with a mesh size of 0.25 mm. With a typical particle size distribution, 49% (by weight) of the particles pass through a sieve with a mesh size of 0.063 mm and 78% (by weight) of the particles pass through a sieve with a mesh size of 0.125 mm.

[0079] In the case of the exemplary filler 3c with the fine-grained quartz flour of type Millisil W4 of the grain size group 0 / 0.25, capillaries with a capillary suction height of approximately 1 m result, which is slightly more than the length of the capillary line 3.

[0080] Depending on the tree species and location, the approximate water requirement of a tree is around 2 to 5 liters per square meter. 2 Crown projection area and day. For a tree with a crown diameter of 10 m, this would be between 160 and 400 liters per day.

[0081] With a total of four identical such capillary tubes 3, which are arranged in a square pattern centrally / centrically and symmetrically within a radius of 0.5 m around the center of the liquid reservoir 2 (see Fig. 2) A plant PF to be irrigated, such as a tree with a crown diameter over 5 m, can be adequately irrigated in the root area WB even during prolonged dry periods.

[0082] Instead of one large capillary tube 3, several capillary tubes 3 at regular intervals are suitable to ensure even extraction of the liquid reservoir 2 and even irrigation of the root area WB.

[0083] The inlet 4 and outlet 5 automatically regulate the fill level in the liquid reservoir 2. This ensures sufficient irrigation even as the tree grows and its water requirements increase. Outlet 5 adjusts the fill level in the liquid reservoir 2 to prevent waterlogging in the root zone WB of the plant PF, even when the plant's water needs are relatively low, for example, shortly after planting.

[0084] Advantageous further developments of the invention result from combinations of the features disclosed in the description, the figures and the claims. Reference symbol list 1 System / Arrangement 2 liquid reservoirs (drainage ditches) 3 Capillary tube (wick) 3a Wall 3b Filter fleece 3c Fine-grained filling with capillary action 3D openings in the wall 4 Inlet 4a,c Inlet line 4b Inlet shaft 5 Procedure 5a,c Drain line 5b Drainage shaft D3 diameter capillary tube ER soil L3 Length of capillary tube L3d spacing of openings in the wall PF plant (tree) WB root area of ​​the plant X3 line axis QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 20 2017 003 834 U1

[0003] DE 36 33 390 A1

[0003] Cited non-patent literature

[0000] DIN EN ISO 9863:2020-04

[0023] DIN EN ISO 12236

[0075] EN ISO 11058

[0075]

Claims

[1] System (1) for plant irrigation, comprising a liquid reservoir (2) that can be arranged in the ground (ER) and at least one capillary line (3) that can be coupled to the liquid reservoir (2) and which is configured to convey, in a state coupled to the liquid reservoir (2), a liquid stored in the liquid reservoir (2) by capillary action to the root zone (WB) of a plant (PF) arranged above the liquid reservoir (2). [2] System (1) according to the preceding claim, characterized by , that the liquid storage unit (2) has a grid-shaped housing and a trough- or channel-shaped liquid collection section. [3] System (1) according to any of the preceding claims, characterized by , that the system (1) comprises a plurality of capillary tubes (3). [4] System (1) according to any of the preceding claims, characterized by, that the capillary line (3) in particular comprises a tube (3a) which forms at least one wall (3a) of the capillary line (3). [5] System (1) according to any one of the preceding claims, characterized by , that the capillary tube (3) has a wall (3a) that is at least partially permeable to water, in particular perforated. [6] System (1) according to any one of the preceding claims, characterized by , that the capillary tube (3) has at least one filter fleece, in particular made of plastic, on the inside of a wall (3a). [7] System (1) according to any of the preceding claims, characterized by , that the capillary line (3) has a capillary filler (3d) such as quartz flour, with a high proportion of about 49% of fine particles with a particle size of less than 63 µm. [8] System (1) according to any of the preceding claims, characterized by, that the capillary tube (3) has a capillary filler (3d) such as quartz flour, in particular with a maximum particle size of 250 µm. [9] System (1) according to any of the preceding claims, characterized by , that the capillary tube (3) has a capillary suction height which is approximately equal to a length (L3) of the capillary tube (3). [10] Arrangement comprising a system (1) according to one of the preceding claims, wherein at least one liquid reservoir (2) is arranged in the soil (ER) and the at least one capillary tube (3) is coupled to the liquid reservoir (2) in such a way that it directs a liquid stored in the liquid reservoir (2) by capillary action into the root area (WB) of a plant (PF) arranged above the liquid reservoir (2). [11] Arrangement according to the preceding claim, characterized by , that the fluid storage unit (2) comprises a plurality of communicating storage modules.

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