WO2022112982A1

WO2022112982A1 - Animal barn floor

Info

Publication number: WO2022112982A1
Application number: PCT/IB2021/060956
Authority: WO
Inventors: Karel Van Den Berg; Arie Huyzer; Korstiaan Cornelis BLOKLAND; Frederik Jan DE LANGE
Original assignee: Lely Patent N.V.
Priority date: 2020-11-25
Filing date: 2021-11-25
Publication date: 2022-06-02
Also published as: EP4250911A1; NL2026980B1

Abstract

The inventions relates to a floor for an animal barn, comprising a slatted floor having a walking surface and at least one slotted through opening that opens out in an underlying manure cellar; and a slot element for reducing the slot opening, wherein the slot opening has a first cross section in a plane parallel to the walking surface, a second cross section perpendicular to the walking surface, and a periphery, wherein the slot opening has a step over at least a part of the periphery at a distance different from zero from the walking surface and from an opposite surface, thereby dividing the slot opening into a first partition extending from the walking surface to the step, and a second partition extending from the step to the opposite surface, wherein the slot element comprises an insert having a top surface and wherein the top surface is provided with a plurality of apertures for the passage of a fluid to the manure cellar, and wherein solids remain at the top surface, and wherein the slot element is inserted into the first partition and supports on the step.

Description

ANIMAL BARN FLOOR

BACKGROUND OF THE INVENTION

Field of the invention

The invention relates to an animal-barn floor for separating urine and feces. The invention also relates to an animal barn comprising such a floor. Furthermore, the invention relates to an animal barn system comprising such a floor.

Description of the related art

Traditionally, cattle is kept in an animal space on a slatted floor with slot-shaped openings that open into an underlying manure cellar. Characteristic of such floors is that the width of the slot opening remains the same in the downward direction or increases along its depth. Feces and urine fall through the slot openings and end up in the manure cellar that serves as storage for the mixture of urine and feces, the so-called slurry. In this slurry, all fertilizer components such as phosphates, fibers, nitrogen are present. The reaction of urine with feces produces ammonia that exits through the slot openings into the barn and eventually to the environment where it has a harmful effect.

Due to regulations and environmental protection, it is desirable to fertilize with individual fertilizer components. To separate slurry into individual manure components is tricky and expensive.

It is known that a perforated barn floor will let urine through to an underlying space. In addition, the barn floor is covered with fibrous material. Air with ammonia above the urine is filtered off and passed through an air washer. The aim is to evaporate and remove all ammonia from the urine in this way. Feces stays on top of the floor. A perforated floor has the disadvantage that the holes may be blocked by the fibrous material, feces and other dirt quite easy.

Patent publication NL2018338 discloses a slatted floor with a walking surface and at least one slot opening that opens up to a manure cellar, and wherein in the slot opening a slot element is inserted to reduce the opening of the slot opening. The slot element comprises a profile that fits into the slot opening, and a hole that allows urine to pass through. However, slatted floors do not have standardized slot opening sizes, such that for each individual floor a tailored element must be made. In addition, the number of slots to be provided with such an element is very large due to the size of a barn floor, such that this is very tiresome and heavy work.

It would therefore be desirable to provide a barn floor that alleviates at least some of the perceived inconveniences of the prior art.

BRIEF SUMMARY OF THE INVENTION

According to the invention, there is provided an animal barn floor comprising a slatted floor for an animal space having a walking surface and at least one slot opening that opens out in an underlying manure cellar, and a slot element for reducing the slot opening, wherein the slot opening has a first cross section in a plane parallel to the walking surface, a second cross section perpendicular to the walking surface, and a periphery, wherein the slot opening has a step over at least a part of the periphery at a distance different from zero from the walking surface and from an opposite surface, thereby dividing the slot opening into a first partition extending from the walking surface to the step, and a second partition extending from the step to the opposite surface, wherein the slot element comprises an insert having a top surface and wherein the top surface is provided with a plurality of apertures for the passage of a fluid to the manure cellar, and wherein solids remain at the top surface, and wherein the slot element is inserted into the first partition and supports on the step.

The animal barn floor may be made up of at least one floor element, for example, one or multiple floor elements forming at least part of the animal barn floor. Underneath the slatted floor, a manure cellar, i.e. a reservoir for storing manure, urine and/or a mixture thereof called slurry, is provided. The slot openings of the slatted floor open up into the reservoir when the assembly is in use as the animal barn floor. The slot element has multiple apertures, forming perforations, such that in use a perforated floor is achieved. The apertures preferably have dimensions that allow urine, and other fluids, to flow through the slot element, via the slot opening, to the underlying reservoir, when the barn is in use, i.e. when animals are kept in the barn, and the animals walk on the walking surface of the slatted floor. Because the apertures may be relatively narrow at the walking surface, there is only a small connection of the animal space with the underlying reservoir or manure cellar. Vapors such as ammonia thus remain largely in the reservoir. In addition, the apertures in the top surface of the slot element may be so narrow that feces cannot easily pass to the reservoir. The larger part of the feces will remain on the top surface and walking surface, and can be removed separately from the urine. Removal of the feces can take place by a manure removal vehicle, such as a manure suction robot or manure slide.

The step may be defined as a sudden change in inner dimensions of the slot opening, e.g. a sudden narrowing or widening of the slot opening, or a combination thereof. The step may form a peripheral protrusion extending from an interior surface, preferably an axially symmetrical peripheral protrusion. Alternatively or additionally, the step may be formed by a peripheral indentation extending into the interior surface.

Furthermore, the apertures can form a flow regulator to control an airflow from the barn to the reservoir, such that any ammonia formed on the walking surface of the barn floor is sucked into the reservoir, thereby reducing the concentration of ammonia in the barn and therefore reducing the odor and improving the environment in the barn.

The step divides the slot opening in a first and a second partition that may have different dimensions and/or shapes. In use, the opposite surface is a bottom side of the barn floor that faces the reservoir, opposite of the walking surface. The walking surface is the surface that the animals will walk on. Furthermore, it is preferred that the slatted floor comprises concrete, or is made of concrete, and is preferably made of reinforced concrete. Concrete is used in most barn floors, but alternative any suitable materials may be used.

The slot element is provided in the first partition, and is supported by the step. The step thus functions as a support for the slot element, to prevent the slot element from sliding down the slot opening.

It is preferred that an opening of the slot opening at the opposite surface is wider than the aperture of the slot element and/or than an opening of the slot element at the walking suface.

According to an embodiment, the slot opening has ends at opposite sides and the step has an end periphery, and wherein the end periphery of the step varies in shape over a longitudinal direction of the slot opening, wherein the step is relatively narrow at at least the ends of the slot opening. The slot opening has an elongated shape that has ends at both sides. At the ends, the step may be narrower (and the width of the slot opening at the step may be larger) than at another location in between the ends of the slot opening. Preferably, the narrowing of the step coincides with the location of the apertures in the slot element, such that the width of the slot opening is larger at the apertures of the slot element. Preferably, the step may be absent, i.e. have a width of zero, at the location in the slot opening that coincides with the apertures in the slot opening.

Further, the step may comprise a support surface on which the slot element supports, and wherein the support surface slopes upward towards the end periphery. The upward slope of the support surface increases the engagement between the slot element and the step, and stabilizes the positioning of the slot element within the first partition of the slot opening.

Alternatively or additionally, the end periphery of the step comprises an upward end flange, wherein the end flange engages the slot element. The end flange can engage with a recess in the slot element, or can extend into an interior of the slot element when a supporting wall of the slot element supports on the step.

According to an embodiment, the slot element comprises a peripheral supporting wall that supports on the step of the slot opening, wherein the supporting wall and the top surface enclose an interior of the slot element. The supporting wall can support on the step with along the full periphery, or along a part of the periphery. In the latter case, the supporting wall may have one or more recesses that extend from a supporting edge to the top surface, or the step may have recesses for releasing dirt from the slot opening.

A support ring may be provided between the slot element and the step, wherein the support ring is commensurate with the step and/or the supporting wall of the slot element. Such a support ring is for stabilizing the slot element within the first partition, for instance to prevent that the slot element may be pushed into the slot opening, or for adjusting the orientation of the top surface with respect to the walking surface.

The support ring may be used to increase the support surface of the step, i.e. narrowing the slot opening at the step.

The interior of the slot element may be a dome or a frustum at at least the apertures in the second cross section, wherein the dome or the frustum extends from the aperture tot an underside of the slot element. As such, the slot element may have multiple interiors in relation to the apertures. The interior or interiors may thus be shaped as recesses in an otherwise solid slot element.

The dome may be formed as half a sphere, half an ellipsoid, or as an onion. A sphere cap is possible too. The base of the dome may be a circle, an ellipse or a polygon (triangle, square, etc.). In order to have an increased flow into the slot opening, a flange may extend downwards from the top surface into the interior of the slot element, wherein the flange is provided to enclose the aperture. The flange is provided around the aperture and forms a drip edge for any liquid that flows through the aperture in the slot element. The flange may be funnel-shaped, axially symmetrical, or axially asymmetrical, to guide a fluid flow towards a center of the slot opening. An axially asymmetrical funnel may be shaped as an oblique cone. A top angle of the funnel or oblique cone may range from 30 to 60 degrees, preferably from 45-55 degrees, more preferably about 50 degrees. According to an embodiment, a top surface of the slot element is flush with the walking surface of the slatted floor. Alternatively, the top surface of the slot element is offset from the walking surface of the slatted floor.

The top surface of the slot element may slope downward towards the apertures. The slope towards the apertures creates a faceted top surface where fluids flow easier towards the apertures then with a flat top surface.

Alternatively or additionally, the top surface may be provided with grooves directed to and opening into the apertures of the slot element. Fluids, in particular liquids, may gather in the grooves and flow to the apertures. The multiple apertures may be distributed in a pattern across the top surface of the slot element.

The second partition may be shaped as a frustum, in particular a right frustum, extending from the step to the second surface, forming a truncated A (capital letter lambda) or V-shape along the second cross section of the through hole. The second partition may be shaped as a frustum extending from the step to the second surface, forming a truncated A (capital letter lambda) or V-shape along the second cross section of the through hole. Alternatively, the second partition may be shaped as a dome, i.e. the upper part of a hollow sphere, extending from the step to the second surface, forming (part of) a semi-circle along the second cross section of the through hole. The second partition may be shaped as a cylinder, in particular a right cylinder, extending from the step to the second surface, forming an inverted U-shape, along the second cross section of the through hole.

A frustum is the portion of a 3D-shape (normally a cone or pyramid) that lies between one or two parallel planes cutting the 3D-shape (also known as a solid geometry or solid). A right frustum is a parallel truncation of a right pyramid or right cone. A pyramid is a polyhedron formed by connecting a polygonal base and a point, called the apex. Each base edge and apex form a triangle, called a lateral face it is a conic solid with polygonal base. A right pyramid has its apex directly above the centroid of its base. A cone is a three-dimensional geometric shape (a solid geometry or solid) that tapers smoothly from a fiat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A right circular cone is a cone with a circular base having the axis passing through the apex and the center of the base at right angles to its plane.

The first partition may have a width at the walking surface ranging between 25 to 45 millimeters (mm). Hoof prints of animals can be about 5G-8Qmm in length and 40~-50 mm in width. It is preferred that the first partition and/or the slot element are dimensioned such that the width does not exceed the smallest dimension of the animal hoof. The step dividing the first and second partitions may reduce this width. The length of the first partition, and thus the slot opening at the walking surface, may vary, but will be larger than the width of the first partition (slot opening), hence to the slotted shape of the slot opening.

Furthermore, the second cross section may have a varying width, because of a changing shape of the slot opening along a thickness of the slatted floor. As such, along the second cross section the width of the first partition may be relatively constant, whereas the width of the second partition may change from relatively narrow extending from and with respect to the first partition, thus forming the step, to relatively wide at the second surface of the floor, which may result in a frustum as described above. The width of the second partition may vary along the second cross section through an angled inner surface of the second partition. For instance, the angle between the inner surface and the second surface may range from less than 90 degrees to 55 degrees, i.e. from near perpendicular to the second surface to a slanted orientation. Preferably, the angle between the inner surface and the second surface has a maximum of 30 degrees.

Preferably, the aperture in the slot element has a diameter or a smallest dimension between 5 and 10 millimeter (mm). It is advantageous if the aperture is circular with a diameter between 5.0 and 10 mm, preferably between 7.5 and 8.5 mm. It has been established experimentally that an aperture of such size on the one hand allows a rapid passage of urine or other liquid or gas, and on the other hand is sufficiently small to prevent feces from passing.

The slot element may be removably inserted into the first partition. This makes the slot element easy to revise upon damage or wear, and a replacement of the insert is possible. For this embodiment, the slot element may comprise a base and a peripheral wall extending from the base, enclosing an insert interior, wherein an exterior surface of the base forms the top side of the insert, and an exterior surface of the peripheral wall faces the interior surface of the through hole, and together forming an exterior surface of the insert, wherein the insert has similar width dimensions as the first partition, such that the insert has a form fit with the first partition. Preferably, the peripheral wall is perpendicular to the top side of the insert on at least one side, i.e. an interior and/or an exterior side.

The slot element may be inserted into an existing slot opening, or be inserted upon manufacture of the slatted floor, for instance cast into concrete used to make the slatted floor. A cast-in insert may also be removable, depending on choice of material of the insert. In an embodiment, the step is shaped as a peripheral indentation extending into the interior surface of the through hole. The insert may be shaped to have a form fit with the first partition and the indentation forming the step, such that the insert has a protrusion extending into at least part of, but preferably the whole of, the peripheral indentation of the step. The insert is then supported by the protrusion in the indentation of the step.

Moreover, in another embodiment, the step may be formed by a combination of a peripheral protrusion and a peripheral indentation. The insert may be shaped to have a form fit with the first partition and the indentation forming the step, such that the insert has a protrusion extending into at least part of, but preferably the whole of, the peripheral indentation of the step. Furthermore, a free end of the insert may extend beyond the peripheral indentation, such that the free end supports on the peripheral protrusion of the step.

Furthermore, the insert may have a cylinder-shaped, a dome-shaped or a frustum-shaped interior that extends within the interior from the opening of the insert to a bottom side of the insert. The exterior wall forms the outer boundary of the shaped interior of the insert. The interior of the insert thus widens out towards the bottom side, thereby preventing capillary action in the opening of the insert, but in addition also increasing the interior surface of the insert.

In an embodiment, the exterior surface of the peripheral wall facing the interior surface of the through hole, i.e. the first partition, may comprise protrusions, such that the insert has a clamp fit with the first partition. It is desired that the insert is removable from the through hole, for instance for replacement when the insert is broken or otherwise worn out. However, when the insert is in the through hole, it is desired that the insert remains where it is. Thus, a form fit or clamp fit of the insert in the through hole, in particular in the first partition, is preferred.

The slot element can also be made of any suitable material, for instance wood, a plastic, a metal or any combination thereof. Preferably, the slot element is elastically deformable under compression. This may result in that under compression the top surface of the slot element is offset with the walking surface. As such, an elastic material is preferred, such as a rubber or elastomer. A flexible supporting wall is also possible to achieve elastic deformability. Plastic inserts can be made with injection molding or other suitable method of manufacturing. Possibly, the slot element may be made of a relatively thin metal plate material, or of a flexible plastic material. The flexibility and/or deformability of the slot element may assist in the removal of any feces in or on the slot element, as the slot element (and possibly the aperture) may deform upon (partial) accession by an animal’s hoof. Such deformation may loosen attached feces. Preferably, the supporting wall is elastically deformable under compression, such that under compression the top surface of the slot element is offset with the walking surface.

According to an embodiment, the multiple through holes are arranged in a pattern across the floor. The pattern may be random, linear, circular, square, a grid, or any other pattern. It is preferred that the number of through holes in the floor is between 20 to 50 through holes per square meter, more preferably between 25 to 35 through holes per square meter, in particular about 30 through holes per square meter. This number of through holes is sufficient to sustain the pressure difference between the barn above the floor and the reservoir below the floor.

Furthermore, the walking surface of the slatted floor may comprise a pattern of notches having a depth with respect to the walking surface, and that open out into the slot opening. The notches may form a parallel pattern, or form an intersecting pattern. The walking surface may alternatively or additionally be provided with a pattern of protrusions, such as knobs or studs. To avoid a slippery floor if a flat and smooth walking surface, is used, the notches and/or protrusions in the floor may provide some roughness and therefor grip on the slatted floor when it is covered with feces and urine. In addition, the walking surface may have a rough texture. Furthermore, the notches may enhance the drainage of the urine to the slot openings and thus to the reservoir below the slatted floor. As a result, urine from the surrounding area can flow faster through the apertures to the reservoir underneath the barn floor, thus allowing fewer emissions of ammonia vapors from the barn floor.

Preferably, the depth of the notches varies along a longitudinal direction of the notches to form a sloping notch, wherein the depth of the notch is at its maximum at an end opening out into the slot opening. The depth of the notch at the end may be level with the top surface of the slot element.

A sloping notch has the advantage that urine will flow to the slot openings and apertures even easier. Furthermore, any airflow towards the apertures may be enhanced by the notches that guide the flow to the slot openings. Preferably, the depth of the notch is greater than zero and smaller than 10 millimeter, preferably between 1 and 6 millimeter. The walking surface of the slatted floor may be a flat surface, or may slope towards neighboring slot openings, such that relatively higher parts and lower parts are created, wherein the lower parts coincide with the slot openings.

The slatted floor may be made in one piece at the location of the animal barn, and thus comprising one floor element. Advantageously, the slatted floor may comprise at least two floor elements, wherein each floor element has side edges, and wherein at least a first side edge of a first floor element forms an interface with a second side edge from a second floor element. Building a slatted floor out of more floor elements will allow for manufacturing the floor elements remotely and/or as a prefabricated slatted floor that can be bought off the shelf. The floor elements may be placed edge to edge to form the slatted floor.

The invention also relates to an animal barn comprising a slatted floor as described above. More than one embodiment of the floor as described above may be combined in the animal barn, as the requirements for the floor may vary over the barn area.

The invention further relates to an animal barn system with a slatted floor as described above, or a barn comprising such a slatted floor, wherein the barn system comprises an air extraction device, in particular a blower, for extracting air from underneath the floor. The air extraction device reduces the air pressure, such that air is sucked out of the animal space or barn above the floor. This results in an additional reduction of emissions to the environment. Additionally, the airflow above the floor ensures rapid flow of urine through the holes.

In particular, the animal barn system comprises an air washer coupled to the air extraction device to capture ammonia present in the extracted air. The air washer or scrubber may contain an acid solution, such as sulfuric acid or nitric acid. The air above the liquid layer, which will generally mainly consist of urine, has a high ammonia content. By forcing the air from the reservoir through an air washer, known per se, the ammonia is bound in the scrubber's acid solution.

It has been found experimentally that a particularly advantageous effect is obtained if the air extraction device creates a lower pressure under the floor relative to the pressure above the floor. Preferably, the pressure difference is between 0.3 mbar and 1.0 mbar. The air extraction device thus creates a low vacuum under the floor, with a lower pressure than atmospheric pressure. The pressure under the floor is preferably 0.3 to 1.0 mbar lower than atmospheric pressure that is active above the floor. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows schematically an animal barn system according to the invention.

Figures 2 to 7 show embodiments of the animal barn floor and the slot elements according to the invention.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS Figure 1 schematically shows an animal barn system 40 according to the invention, comprising a floor 1 for an animal space or barn 41, the floor 1 comprises a slatted floor 2 having a walking surface 3 and multiple slot openings 10 that open up to an underneath reservoir or a manure cellar 46. Figure 2A shows a cross section of the barn floor 1 with the slatted floor 2 with the slot openings 10 and slot elements 20. The slot elements 20 have apertures 21 that open out to the reservoir beneath the barn floor 1.

The system 40 comprises an air extraction device 42, which can be a fan, in particular a blower 43, for extracting air under the assembly. The system 40 comprises an air washer 44 coupled to the air extraction device 42 to be present in the extracted air to capture ammonia. The blower 43 provides a low vacuum of approximately 0.7 mbar under atmospheric pressure, which is the difference between the prevailing air pressure in the animal space 41 and the lower pressure in the manure cellar 46 located under the barn floor 1. Because the apertures 21 are relatively small and the free space in the reservoir under the barn floor 1 is relatively large, the prevailing pressure in the reservoir will be relatively constant seen over the entire free space. In other words, the pressure gradient in the direction of the blower 43 is small.

The air washer 44 is designed as a packed bed-washing column. Acid absorbent liquid in the form of diluted sulfuric acid or diluted nitric acid is pumped by a pump 47 from underneath a packed bed 48 to a sprayer 45 above the packed bed 48. The ammonia-rich air extracted by the blower 43 is introduced in countercurrent under the packed bed 48 and flows upwards in countercurrent with the absorbent liquid. The absorbent liquid absorbs, among other things, the ammonia and makes it soluble as ammonium. In purified form, the air is conducted via an outlet 49 to the outside environment. The packed bed 48 can be made from different types of fillers and serves to increase the contact surface of the absorbent fluid with the air to be purified. The air washer 44 can also be carried out in transverse flow, wherein the airflow is being lead through the packed bed 48 in a horizontal direction. The packed bed 48 can also be in the form of a cloth over which the absorption liquid runs and the air to be washed is passed through in transverse flow.

After some time, the amount of dissolved ammonia in the absorbent causes a pH increase, such that the absorbent should be replaced. The resulting saturated and still slightly acidic absorption liquid is a nitrogen-containing fertilizer as so-called flushing water. In order to be able to postpone replacement, in an embodiment not shown, the air washer comprises an acid dosing system to be able to keep the pH of the absorption liquid constant.

In addition to ammonia, water vapor from the manure cellar 46 will also pass through the air washer 44 and be removed. This will lead to a thickening of the liquid in the manure cellar 46. This liquid is rich in salts; in particular, potassium salts, and is therefore a good potassium fertilizer.

An autonomous manure suction robot 100 runs between the animals over the floor 1. This robot 100 removes solid feces 101 that largely remain on the walking surface of the floor 1 and a top side 22 of the slot elements 20, and then dumps the feces in a separate space, not shown. In an embodiment not shown, the feces 101 are removed by a pulled manure slide. The collected feces 101 can be further processed by, for example, drying or pressing whereby manure fibers are removed from the feces 101. Contact of feces 101 with urine 102 provides an enzymatic conversion reaction of urea in the urine 102 to ammonia. By regularly cleaning the barn floor 1 , for example every hour, the feces 101 have no or at least less chance to react with the urine 102 on the walking surface. By using a suction robot 100 for this purpose, the feces 101 are removed from the floor 1 on site and the feces 101 are not spread over the floor, which can easily lead to blockage of the apertures 21.

Because the feces 101 are not mixed with the urine 102, almost all phosphate remains in the feces and the solids percentage is relatively high. Eventually, the excretion products (feces 101 and urine 102) of a farm animal 41 in the animal space 41 are separated into three parts in a relatively simple manner: phosphate-rich solid feces 101 with a high organic content, a potassium-rich liquid and a nitrogen-rich liquid. These parts can be used for specific fertilization processes and have a value that is higher than that of the slurry that generally results when feces and urine 102 are dumped in a manure cellar together.

In order to achieve that the urine 102 and feces 101 are separated, and in addition that the blower 43 causes a low vacuum in the reservoir 46, a plurality of apertures 21 are needed in the floor 1. Traditional perforations in a concrete animal floor are usually blocked easily by spread-out feces on the floor or other dirt. Enlarging these perforations is not favorable, due to an increased risk of harm to the animals through spraining or fracturing of a leg due to missteps in a perforation.

Figures 2 to 7 show several embodiments of the slot element and the slatted floor according to the invention that can solve the problems of the traditional floors used in animal barns. The floor 1 of the barn system shown in Fig. 1 comprises multiple slot openings 10 that open up to the reservoir 46 underneath the floor 1. The slatted floor 2 has a walking surface 3 and a surface 4 that is opposite of the walking surface, i.e. the opposite surface 4. The walking surface 3 is the floor surface that animals 41 walk on. The opposite surface 4 faces the reservoir 46. The slot openings 10 extend from the walking surface 3 to the opposite surface 4 over the whole thickness of the slatted floor 2.

Figure 2A shows a slot opening 10 along a cross section perpendicular to the walking surface 3 and opposite surface 4, i.e. the second cross section. A first cross section of the slot opening 10, parallel to the walking surface 3 and/or the opposite surface 4, is not shown. The second cross section shows a first partition 11 and a second partition 12, separated by a step 13. The first partition 11 comprises a slot element 20. The second partition 12 is shaped as an inverted frustum (a truncated A-shape (capital letter lambda) in 2D) that elongates in a longitudinal direction, forming a slot, and narrows from the step 13 towards the opposite surface 4. The slanting surface of the second partition 12 increases the area of the inner surface of the slot opening, such that more urine can vaporize along the flow path to the reservoir 46.

The slot element 20 is supported on a support surface 15 of the step 13. In between the slot element 20 and the support surface 15, a support ring 16 is provided. The support ring 16 offers additional support to the slot element 20, especially as it extends the surface on which the slot element 20 supports. The slot element 20 has an aperture 21 that extends between a top side 22 and an interior 26 of the slot element 20. Fig. 2A shows an interior 26 of the slot element 20 having a dome-shaped cross section at the apertures 21. The interior 26 may be dome-shaped in three dimensions at the apertures 21 , or may extend longitudinally between ends of the slot element 20. The slot element 20 has an aperture 21 , aligned and centered with respect to the first and second partition 11 , 12 of the slot opening 10.

The slot element 20 can be formed of a flexible material, such as a rubber or elastomer that will deform under the weight of an animal when a leg is put (partially) on the slot element 20. The deformation will assist in loosening any feces that has accumulated on and in the slot element 20. The top side 22 of the insert 20 may be off set from the first surface 3, i.e. not flush. The offset can either be that the slot element has a height lower than the depth of the first partition, i.e. the slot element 20 is recessed with respect to the walking surface 3, or that the slot element 20 has a height higher than the depth of the first partition, i.e. the top side 22 of the slot element 20 extends beyond the walking surface 3. The latter version has the advantage that when using a rubber or elastomer solid slot element, as shown in Fig. 2, the slot element 20 may more likely be deformed when an animal (partially) accesses the insert with a leg.

The first partition 11 has a constant first cross section, i.e. the dimensions of the first cross section at the first partition does not change when travelling along the thickness of the slatted floor. The first cross section of the first partition 11 may vary along the thickness of the slatted floor 2, especially when a draft angle of a floor mold is needed for a cast concrete slatted floor 2. The second partition 12 has a varying first cross section, i.e. the dimensions of the first cross section at the second partition changes when travelling along the thickness of the slated floor 2.

Figure 2B shows that the walking surface 3 of the slatted floor slopes towards neighboring slot openings, such that relatively higher parts and lower parts are created, wherein the lower parts coincide with the slot openings.

Figure 2C shows a top view of the slatted floor 2 without the slot elements 20. The slot openings 10 show the step 13 having a periphery 19. The step 13 varies in dimensions, such that the periphery 19 has curved parts at the ends 18 of the slot opening 20 and in between the ends 18. The curved parts in the periphery 19 form wider parts of the slot openings that coincide with the apertures 21 of the slot element 20, see for instance Figure 3A and B. Fig. 2C further shows that the walking surface 3 comprises grooves 17 that end and open out at a slot opening 10. The grooves 17 aid in the flow of fluids, both gasses and liquids, towards the slot opening 10 and thus to the apertures 21 of the slot element 20.

Figure 3 shows an embodiment of the slot element 20 that can be used in the slot opening as shown in Fig. 2C. Fig. 3A shows a top view of the slot element 20, looking at the top side 22. The slot element 20 is shaped as an elongated body that has a greater length than width dimension, as with an oblong. The transverse sides of the slot element 10 are shown to be rounded or curved. The top side 22 is provided with a downward slope 29 towards the apertures 21 , such that the flow of fluids towards the apertures 21 is enhanced. The main fluids involved may be urine, water and/or gaseous ammonia. Fig. 3B shows the underside 28 of the slot element 20 where the interior 26 of the slot element 20 is centered with the aperture 21 and has a circular base. The apertures 21 may be centered with respect to the longitudinal sides of the slot element 20. Moreover, the apertures 21 are centered with respect to the slot opening 10. In addition, the underside 28 shows an anchoring element 27 that can be used to anchor and center the slot element 20 with respect to the slot opening 10, in particular at the relatively narrow parts of the slot opening 10 as shown in Fig. 2. The slot element 20 is shown to be solid in between the apertures 21, in particular at the anchoring elements 27, as shown in Fig. 3C.

Figure 4 shows a further embodiment of the slot element 20 inserted into the first partition 11 of a slot opening 20. The slot element 20 has a peripheral wall 23 and a top side that enclose the interior 26 of the slot element 20. The peripheral wall 23 is formed as a spring element and can thus be deformed under compression. Upon release of the compression, the peripheral wall 23 will move back to its original shape. The cycle of compression and release have a pumping effect, which may enhance the flow of urine and/or ammonia to the reservoir 46. The peripheral wall 23 supports on the support surface 15 of the step 13. The interior 26 opens towards the second partition 12 such that fluids flowing through the aperture 21 is allowed to flow to the reservoir 46 via the second partition of the slot opening 10.

Figure 5 shows an embodiment of the floor 1 with the slatted floor 2 comprising a slot opening 10 and a slot element 20 inserted into the first partition 11 of the slot opening. The walking surface 3 of the slatted floor 2 is provided with grooves 17, as shown in the top view of Fig. 2C. The peripheral wall 23 of the slot element 20 supports on the support surface 15 of the step 13, wherein the support surface 15 slopes upward towards the end periphery 19. The sloping support surface 15 stabilizes the position of the slot element 20 in the slot opening 20. The peripheral wall 23 is shown slightly bent to imply that the peripheral wall is flexible and elastically deformable under compressional load, see also Figure 7B.

Surrounding the aperture 21, a flange 24 that extends downward towards the step 13 is provided. The flange 24 encloses the aperture 21 and functions as a drip ring to help the urine drips fall towards the reservoir 46.

Figure 6 shows perspective views of two other embodiments of the slot element 20. Fig. 6A shows a slot element 20 that has notches 25 on the top side 22. The notches 25 can open out into an aperture 21 , as shown for the combined notches 25 and apertures 21 in Fig. 6A.

Fig. 6B shows a slot element 20 having a top side 22 and a peripheral wall 23 extending from the top side 22 as shown the previous figures. Here, the peripheral wall 23 does not show a continuous curved plane, but recesses 30 at various locations along the peripheral wall 23. Such recesses 30 are useful to release any captures dirt of manure between the slot opening 10 and the slot element 20 in use. Upon deformation by compression of the peripheral wall 23, as described and shown above, dirt and/or manure trapped in the slot opening 10 may be released.

Figure 7 shows a further embodiment of the floor 1. Fig. 7 A shows that the first partition 11 is shown as an inverted frustum, similar to the second partition 12. The step 13 comprises a support surface 15 and a flange 14 that engages the peripheral wall 23 of the slot element 20. The flange 14 thus stabilizes and centers the slot element 20 with respect to the slot opening 10.

Fig. 7B shows a slot element 20 that is elastically deformed under the influence of compressional force exerted by a hoof of an animal 41, in particular a cow’s hoof. The width dimensions of the slot opening 10 and therefore of the slot element 20 are typically smaller than the dimensions of a hoof of the animal 41.

LIST OF ITEMS

1. Animal barn floor 40. Animal barn system

2. Slatted floor 41. Animal 3. Walking surface 42. Air extraction device

4. Opposite surface 43. Blower

44. Air washer/scrubber

10. Slot opening 45. Sprayer

11. First partition 46. Reservoir 12. Second partition 47. Pump

13. Step 48. Packed bed

14. Flange 49. Outlet

15. Support surface

16. Support ring 100. Manure suction robot 17. Groove 101. Feces

18. Slot end 102. Urine

19. Step periphery

20. Slot element 21. Aperture

22. Top side

23. Peripheral wall

24. Flange

25. Notch 26. Element interior

27. Anchoring element

28. Underside

29. Slope

30. Recess

Claims

1. A floor for an animal barn, the floor comprising: a slatted floor having a walking surface and at least one slot opening that opens out in an underlying manure cellar; and a slot element for reducing the slot opening, wherein the slot opening has a first cross section in a plane parallel to the walking surface, a second cross section perpendicular to the walking surface, and a periphery, wherein the slot opening has a step over at least a part of the periphery at a distance different from zero from the walking surface and from an opposite surface, thereby dividing the slot opening into a first partition extending from the walking surface to the step, and a second partition extending from the step to the opposite surface, wherein the slot element comprises an insert having a top surface and wherein the top surface is provided with a plurality of apertures for the passage of a fluid to the manure cellar, and wherein solids remain at the top surface, and wherein the slot element is inserted into the first partition and supports on the step.

2. Floor according to claim 1, wherein the second partition is formed as a frustum extending from the step to the opposite surface, thereby forming a truncated A (capital letter lambda) or V-shape along the second cross section of the slot opening.

3. Floor according to claim 1 or 2 wherein the slot opening has ends at opposite sides and the step has an end periphery, and wherein the end periphery of the step varies in shape over a longitudinal direction of the slot opening, wherein the step is relatively narrow at at least the ends of the slot opening.

4. Floor according to any of the preceding claims, wherein the step comprises a support surface on which the slot element support, and wherein the support surface slopes upward towards the end periphery.

5. Floor according to any of the preceding claims, wherein the end periphery of the step comprises an upward end flange, wherein the end flange engages the slot element.

6. Floor according to any of the preceding claims, wherein the walking surface comprises a pattern of notches having a depth relative to the walking surface, wherein the notches open out to the slot opening.

7. Floor according to claim 6, wherein the depth of the notches varies along a longitudinal direction of the notches to form sloping notches, wherein the depth of the notches is maximum at an end opening into the slot opening.

8. Floor according to any of the preceding claims, wherein the slot element is elastically deformable under compression.

9. Floor according to any of the preceding claims, wherein the top surface of the slot element is flush with the walking surface of the slatted floor.

10. Floor according to any of claims 1-8, wherein the top surface of the slot element is offset with the walking surface of the slatted floor.

11. Floor according to any of the preceding claims, wherein the slot element is removably inserted into the first partition.

12. Floor according to any of the preceding claims, wherein the slot element comprises a peripheral supporting wall that supports on the step of the slot opening, wherein the supporting wall and the top surface enclose an interior of the slot element.

13. Floor according to any of the preceding claims, wherein between the slot element and the step a support ring is provided, wherein the support ring is commensurate with the step and/or the supporting wall of the slot element.

14. Floor according to claim 12 or 13, wherein the interior of the slot element is a dome or a frustum at at least the apertures in the second cross section, wherein the dome or the frustum extends from the aperture tot an underside of the slot element.

15. Floor according to any of claims 12 to 14, wherein the supporting wall is elastically deformable under compression, such that under compression the top surface of the slot element is offset with the walking surface.

16. Floor according to any of claims 12 to 15, wherein a flange extends downwards from the top surface into the interior of the slot element, wherein the flange is provided to enclose the aperture.

17. Floor according to any of the preceding claims, wherein the top surface of the slot element slopes downward towards the apertures.

18. Floor according to any of the preceding claims, wherein the top surface is provided with grooves directed to and opening into the apertures of the slot element.

19. Floor according to any of the preceding claims, wherein the slot element has commensurate dimensions with the first partition, such that the slot element has a form fit with the first partition.

20. Floor according to any of the preceding claims, wherein the multiple apertures are distributed in a pattern across the top surface of the slot element.

21. An animal barn comprising a floor according to any of the preceding claims.

22. An animal barn system with a floor according to any of claims 1-20, or a barn comprising such a floor according to claim 21, wherein the barn system comprises an air extraction device for extracting air from underneath the floor, wherein the air extraction device creates a lower pressure under the floor relative to the pressure above the floor.

23. System according to claim 22, comprising an air washer coupled to the air extraction device to capture ammonia present in the extracted air.