TECHNICAL FIELD
The present invention relates to a system for processing soil. More particularly, the invention relates to a system for processing soil that comprises a soil processing device, arranged to be moved on a soil surface; and a driving device arranged to move the soil processing device on a portion of the soil surface; the soil processing device including a frame, arranged to slide or roll on the portion of the soil surface during operation of the system; at least one substantially horizontal pipe, attached to the frame, extending along an underside of the frame, at a predetermined depth, the pipe having at least one aperture, the pipe being connectable to a vacuum generating device that provides an underpressure in the pipe.
BACKGROUND
There is a general need for systems for processing soil, e.g., for destroying, removing or reducing the content of organic elements such as seeds, fungus, nematodes, or microorganisms in the soil. In particular, there is a need for such a system which make use of a driving device, such as a vehicle, arranged to move a soil processing device on a portion of a soil surface.
In particular, there is a need for such systems that do not rely on particular chemical agents for processing the soil. There is also a need for such systems that fulfil environmental conditions of ecological development and sustainability.
German patent DE-4132705 C1 describes a soil decontamination vehicle which carries a steam boiler linked by a steam line to a steam plough.
Dutch published patent application NL-8100599 relates to a method for sterilizing soil in greenhouses. Steam is passed downwards through the soil. The soil surface is covered to prevent steam loss. A vacuum is generated below or in the soil to be sterilised by means of a system of pipes.
Norwegian published patent application NO-20005184 describes a mobile heat processing principle for soil. Steam or heated gas is drawn into the soil from a moving compartment that is pulled on the surface of the soil. The steam or heated gas is further drawn into a number of suction pipes that are conveyed through the soil with the same speed as the moving compartment. A spade device is arranged to make the soil porous. The compartment, suction pipes and the spade device are mounted on a sled or carriage that may be pulled by e.g. a tractor.
This prior art solution has certain disadvantages. A particular problem with the prior art solution is that vacuum pipes that are conveyed through the soil may easily get packed or stuck by soil, stones, granules, clods or similar particles or material during use. Also, when such packing occurs, it is cumbersome to remove the particles or materials to make the system fully operative again.
SUMMARY
An object of the invention is to provide a system for processing soil, which overcomes the above-mentioned and other disadvantages of the prior art.
The invention provides a system for processing soil as set forth in the appended claims.
As used herein, processing soil may in particular be understood as destroying, removing or reducing the content of organic elements such as seeds, in particular seeds of weeds or unwanted seeds, or fungus, or nematodes, or microorganisms such as undesired microbes or bacteria, from the soil. Processing soil may include sterilizing soil.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic side view illustrating principles of a system for processing soil, during operation.
Figure 2 is a schematic side view illustrating principles of a soil processing device.
Figure 3 is a schematic perspective view illustrating principles of a soil processing device.
Figure 4 is a schematic side view illustrating further principles of a soil processing device.
Figure 5 is a schematic side view illustrating further details of a soil processing device.
Figure 6 is a schematic side view illustrating further details of a soil processing device.
Figure 7 is a schematic side view illustrating further details of a soil processing device.
Figure 8 is a schematic perspective view illustrating further details of a soil processing device.
DETAILED DESCRIPTION
Figure 1 is a schematic side view illustrating principles of a system 100 for processing soil during operation.
The soil has an upper surface 170.
The system 100 comprises a soil processing device 110 which is arranged to be moved on the soil surface 170. The system further comprises a driving device 160, which is arranged to move the soil processing device 110 on a portion of the soil surface 170. As illustrated, the driving device 160 is a vehicle which is attached to the soil processing device 110 and arranged to pull the soil processing device in a direction to the left on figure 1, during normal operation of the system 100.
In an alternative aspect, the vehicle 160 may be arranged to push the soil processing device 110 during normal operation. In still an alternative aspect, the vehicle 160 and the soil processing device 110 may be designed as one and the same unit.
The vehicle includes at least an engine, which may be an internal combustion engine such as a diesel engine. The vehicle may further include a fuel tank, gear device, wheels and/or belts, etc. Alternatively, the vehicle may be electrically driven, by one or more electric motors. The speed of the vehicle may be set by signal input to a vehicle speed adjustment device. The speed of the vehicle may optionally be overridden by a human operator, i.e., a driver. The vehicle may also bee steerable, either by electronic signals or by a human operator, i.e., the driver, or both.
In an alternative aspect, a winch (not shown) may be used as a driving device 160. For instance, a winch may be attached to the soil processing device 110, the winch having a wire wound on a drum or spool, the remote end of the wire being anchored to the ground or an object which is fixed with respect to the ground. The winch may be powered by an electric, hydraulic, pneumatic or internal combustion drive with a variable speed.
In still an alternative aspect, the winch may be reversed, in such a way that the powered drum or spool is anchored with respect to the ground, and the wire’s remote end is attached to the soil processing device 110.
As illustrated, the soil surface 170 is horizontal. It will be understood that the soil surface 170 may usually be substantially horizontal, but in certain cases the soil surface may have a slope, depending on varying natural conditions, in particular the topography of the area which is subject to the use of the system.
The soil processing device 110 includes a frame 112, which is arranged to slide or roll on the portion of the soil surface 170 during operation of the system.
The soil processing device 110 further includes at least one substantially horizontal pipe 114, which attached to the frame 112, extending along an underside of the frame 112. The horizontal pipe 114 is arranged at a predetermined depth, i.e., at a predetermined level below the underside of the frame 112.
Advantageously, the soil processing device 110 includes includes a plurality of parallel pipes 114. For instance, the number of parallel pipes may be between 10 and 20, e.g., 16. The pipes 114 may advantageously be arranged at substantially the same, predetermined depth.
During operation, the pipe or pipes 114 will be buried in the soil, at the predetermined depth, and they will usually be pulled through the soil by the movement of the vehicle 160.
In order to facilitate the positioning and movement of the pipes 114 at the predetermined depth in the soil during operation, a cutting blade 118 may advantageously be arranged at in a plow foot at a leading portion of the at least one horizontal pipe 114. The cutting blade may advantageously be easily replaceable.
In order to facilitate the positioning and movement of the pipes 114 at the predetermined depth in the soil during operation, a cutting wheel 120 may advantageously be arranged at the leading portion of the at least one horizontal pipe 114.
The cutting blade 118 and optionally the cutting wheel 120 may have the effect of making the soil more porous, which results in facilitated positioning and movement of the horizontal pipe 114. The cutting wheel 120 may in particular provide the advantage of cutting straws, plant roots and possibly similar elements that are present below, on or above the surface 170 of the soil.
Each pipe 114 is provided with a plurality of apertures 116 along its length. The number of apertures has been further elaborated in the detailed description with reference to fig. 5 below.
Each horizontal pipe 114 is connectable to a vacuum generating device that provides an underpressure in the pipe, i.e., in the air contained in the pipe 114. The vacuum generating device may include a pump, a fan, or an ejector device.
In operation, the soil processing device 110 further includes a protective cover 150 which is attached to an upper side of the frame 112. The cover 150 may be airtight or substantially airtight, and/or watertight or substantially watertight. The cover 150 may advantageously be made of a flexible material, or at least a part of the cover 150 may be made of a flexible material. In order to prevent or reduce heat loss from the compartment below the cover 150 to the surrounding environment, the cover 150 is advantagously made of a heat isolating material. Substantially vertical side walls 152 may be provided between the frame and the protective cover. The portion of the soil surface 170 and the cover 150, advantageously also the side walls 152, define a compartment that moves along the soil surface 170 during operation, i.e., when the vehicle 160 is in movement and pulls the soil processing device 110 on the soil surface 170. The side walls 152 may advantageously be provided as heat isolating side walls in order to prevent or reduce heat loss from the compartment below the cover 150 to the surrounding environment.
A conduit for a heated gaseous medium is arranged with at least one conduit opening within the compartment. The conduit for a heated gaseous medium is connectable to a heated gaseous medium generator 162. During operation, the heated gaseous medium generator 162 is connected to the heated gaseous medium conduit and provides heated gaseous medium to an inside of the compartment.
The heated gaseous medium typically includes air and steam. In an aspect, the heated gaseous medium may be air with a predetermined or controlled fraction of steam. In a particular aspect, the heated gaseous medium may be steam.
In another aspect, the heated gaseous medium may be dry air. Alternatively, the heated gaseous medium may include air, steam and additional gases or mixtures of gases, e.g. carbone dioxide, furnace gas or fumes.
The heated gaseous medium may have a variable and/or controllable temperature, provided by a heater device. The heater device may be part of the heated gaseous medium generator 162. The heated gaseous medium generator may have a signal input, for instance a power signal input. A power signal applied to the power signal input may affect the power of the heater device, resulting in variation of the temperature of the heated gaseous medium.
The heated gaseous medium may have a variable and/or controllable humidity, provided by a humidifying device. The humidifying device may be a separate unit or a part of the heated gaseous medium generator 162. The humidifying device may for instance include a steam generator which provides steam that is mixed with heated air in a particular mixing ratio in the heated gaseous medium generator 162. The humidifying device may have a humidity signal input. A humidity signal applied to the power signal input may affect the humidity of the resulting heated gaseous medium, resulting in variable and/or controllable humidity of the heated gaseous medium. For instance, the humidity signal input may affect the mixing ratio of steam added to heated air.
The heated gaseous medium generator 162, optionally including the humidifying device, may advantageously be arranged on the vehicle 160. Alternatively, the heated gaseous medium generator, optionally also the humidifying device, may be arranged on the soil processing device 110. Arrangement of the heated gaseous medium generator 162 and optionally the humidifying device on the vehicle will lead to the advantage of avoiding unnecessary load on the soil processing device 110.
As another option, the heated gaseous medium generator may be arranged stationary, i.e., not onboard the vehicle or the soil processing device 110. In this case, a flexible pipe or hose may be arranged to convey the heated gaseous medium from the stationary heated gaseous medium generator to the soil processing device 110.
As still another option, the heated gaseous medium generator may be arranged on a separate trailer or vehicle which is arranged to move along with the vehicle 160 and the the soil processing device 110.
When a plurality of substantially horizontal pipes 114 are arranged in the soil processing device 110, the plurality of pipes 114 may be interconnected with the vacuum generating device by means of a vacuum manifold 304.
In order to facilitate the sliding or rolling movement of the soil processing device along the surface 170 of the soil, and in order to level the soil surface after the digging action of the cutting blades 118 and/or the cutting wheels 120, a rotatable leveling drum may be arranged at the underside of the frame 112.
The system 110 may optionally include a lift-and-tilt arrangement 130. The lift-andtilt arrangement 130 is arranged to lift and tilt the frame with respect to a rear portion of the vehicle 160.
A blanket 154, typically made of a flexible membrane, may be attached to the rear part of the soil processing device 110. During use, the blanket is towed behind the soil processing device 110. The blanket, or a part of its length, may be rolled onto a motorized reel 156. The motorized reel may be actuated by a blanket actuator.
Elements or parts that require electrical power may be powered by a battery carried on the soil processing device 110 or on the vehicle 160. The battery may be rechargeable, and may in some instances be configured to be re-charged by e.g. an electric generator powered by an internal combustion engine on the vehicle 160.
Figure 2 is a schematic side view illustrating principles of a soil processing device 110 included in the system 100.
A cutting blade 118 is arranged at in a plow foot at a leading portion of the at least one horizontal pipe 114, corresponding to the disclosure of figure 1 and its corresponding written description above. A cutting wheel 120 may advantageously be arranged at the leading portion of the at least one horizontal pipe 114, also corresponding to the disclosure of figure 1 and its corresponding written description above.
The substantially horizontal pipe 114 may include a front pipe section 202, which may advantageously be a rigid pipe section without any apertures or other particular features. The rear (downstream) portion of the front pipe section 202 is connected to a series of interconnected, chained pipe sections 204. Hence, a plurality of pipe sections 204 are advantageously arranged along a length of the pipe 114. The pipe sections 204 are advantageously interconnected by connection means 506, further illustrated in figure 5, that allow a certain angular movement between adjacent, interconnected sections 204. This enables a play in the longitudinal, moving direction of the system and avoids or reduces the risk for breaking of the substantially horizontal pipe. For instance, an angular movement of /- 20 degrees, or an angular movement of /- 10 degrees, or an angular movement of /- 5 degrees, may be allowed by the connection means 506. Angular movement may advantageously be allowed in both horizontal and vertical directions.
The pipe 114, including the front pipe section 202 and the remaining pipe sections 204, may advantageously be made of a metal such as steel, or aluminium, or of suitable plastic or composite material. Alternatively, various materials may be used for various sections of the pipe 114.
Also, the connection means 506 may be arranged to allow a rotational movement between adjacent, interconnected sections 204. In one aspect, each section 204 may be allowed to rotate unrestricted. In other aspects, a rotational movement of /- 10 degrees, or a rotational movement of /- 5 degrees may be allowed by the connection means 506.
Figure 3 is a schematic perspective view illustrating principles of a soil processing device 110.
As shown in figure 3, a plurality of parallel, substantially horizontal pipes 114 are arranged in the soil processing device, at substantially the same, predetermined depth below the soil surface 170. Each pipe 114 is terminated at its downstream end by a rear pipe section 406, which has been described in closer detail below with reference to figures 4, 5, 7 and 8.
In the illustrated example, 13 pipes 114 are arranged in parallel. with equal horizontal space between them. Alternatively, the space (width) between each pipe 114 may vary. It should be understood that the number of parallel pipes 114 may be selected according to circumstances. For instance, the number of parallel pipes 114 may be between 5 and 30, or between 10 and 20.
Each pipe 114 is advantageously equipped with a corresponding cutting edge 118 on a plow foot. A vacuum manifold 304 is arranged to interconnect the substantially horizontal pipes. A blowback device includes a blowback manifold 302, at least one controllable valve 306 and an air pressure tank. The blowback device is arranged to apply a high pressure impulse in the at least one horizontal pipe 114 in order to remove unwanted material from apertures 116 in the pipe 114. In the illustrated example, each horizontal pipe 114 is provided with a separate controllable valve 306, in order to apply the high pressure impulse selectively. In order to achieve such selective blowback function, each controllable valve 306 may be individually controllable by an electronic control device.
The air pressure tank may either be provided as a separate tank, or it may advantageously be integrated in a structure of the frame 112 of the soil processing device 110.
Figure 4 is a schematic side view illustrating further principles of a soil processing device.
Figure 4 shows essentially the same as figure 2, and reference is made to figure 2 and its corresponding written description. However, in figure 4 a particular first feature 402 has been identified, which has been disclosed in further detail in figure 6. Also, a particular second feature has been identified at 404, which has been disclosed in further detail in figure 5. Finally, in figure 4 a particular third feature 406 has been identified, which has been disclosed in further detail in figure 7.
Figure 5 is a schematic side view illustrating further details of a soil processing device.
In particular, figure 5 illustrates the second feature 404 identified in figure 4. The second feature 404 is a detail illustrating a pipe section 204 and the interconnection between two pipe sections 204.
Each pipe 114 is provided with a collar 502 around its perimeter. As shown in figure 5, the pipe section 204 may be provided with such a collar 502. More specifically, in the example of figure 4, the pipe section 204 may include two such collars 502, arranged at a distance along the pipe section 204.
A number of apertures 116 are shown, arranged along a perimeter of the pipe section 204. Most typically, the pipe section 204 may have a circular cross section. In this case the perimeter is a circumference of the circular cross section of the pipe section 204. Alternatively, the pipe section’s cross section may take another form, such as square, polygonal, oval or any other suitable form.
In any case, each collar 502 is arranged so as to shield the apertures 116 from surrounding soil, while simultanously facilitating movement of the pipe 114, and its sections 204, through the soil. This may be achieved by providing the collar 502 with an outer shape that diverges in a downstream direction of the pipe 114 and pipe section 204, i.e., the collar 502 may have an increasing perimeter in direction to the right on figure 5. In such an example, the collar 502 may be considered as having a partially conical shape.
Each collar 502 is advantageously arranged to shield a plurality of apertures 116 arranged along a perimeter of the pipe section 204 and the pipe 114.
Advantageously, the apertures 116 are formed as slanted bores in the wall of the pipe 114. More specifically, the bores have axes that diverge in a downstream direction of the pipe 114, i.e., to the right in figure 5. This has two effects, the most prominent being that material (soil, stones, granules, clods) that have become stuck or packed in the apertures will more easily be blown out by application of a sudden high pressure within the pipe 114, as already has been discusses in the above disclosure as advantageous blowback features. A secondary effect of the slanted orientation of the bores is that material (soil, stones, granules, clods) will not so easy become packed in the apertures, in particular in combination with the partially conical shape of each collar 502, which also diverges in a downstream direction of the pipe.
In a particular example, 15 apertures with a diameter of 3,5 mm may be arranged along a perimeter of the pipe section 204. In another example, 9 apertures with a diameter of 6 mm are used. In other examples, the number of apertures along a perimeter may be between 5 and 30, or advantageously between 10 and 20, The diameter of each aperture may be in the range of 2 to 10 mm, or advantageously between 3 to 6 mm. The apertures are advantageously circular, although other shapes are possible. The apertures are advantageously equal along the perimeter, although their shape and size may also vary along the perimeter of the pipe section 204, and/or along the length of each pipe section 204, and/or between one pipe section 204 and another.
As already has been described with reference to figure 2, two adjacent pipe sections 204 may be arranged to allow for angular and/or rotational movement between the sections 204, by means of the connection means 506. Figure 5 also shows the central, longitudinal wire 702 that is arranged within the pipe in order to keep the pipe sections 204 together and in order to allow for angular or rotational movement between the sections 204.
Figure 6 is a schematic side view illustrating further details of a soil processing device.
In particular, figure 6 illustrates the first feature 402 identified in figure 4. The first feature 402 is a detail illustrating an interconnection between a blowback manifold 302, a vacuum manifold 304 and the substantially horizontal pipe 114. The manifolds 302, 304 and the pipe 114 are interconnected by a T-connection element 608. Also shown in figure 6 is the central, longitudinal wire 702 which is arranged within the pipe 114 in order to keep the pipe sections 204 together and in order to allow for angular or rotational movement between the sections 204. The wire 702 is attached to the T-connection element 608 by means of suitable fastening means.
Figure 7 is a schematic side view illustrating further details of a soil processing device. In particular, figure 7 illustrates the third feature 406 identified in figure 4.
The third feature 406 is a detail illustrating a rear section 406 of the substantially horizontal pipe 114, arranged at the pipe 114’s downstream end, i.e., to the right on figure 7. The rear section 406 provides, i.a., the function of opening the pipe 114 to its surroundings by means of a slidable cover 704. When the slidable cover 704 is moved to its front (upstream) position, i.e., to the left on figure 7, a number of cleaning apertures 706 are exposed to the surroundings. If the blowback function is applied while the cover 704 is moved to its front position, the apertures 706 will be cleaned by the overpressure applied by the blowback function.
The slidable cover 704 may be opened manually or by reversing the vehicle and thus the soil processing device 110.
The rear (downstream) end of the wire 702 may be connected to a wire tension adjuster or adjustable stretching device 708.
Figure 8 is a schematic perspective view illustrating further details of a soil processing device.
Figure 8 illustrates further possible aspects of the rear section 406. The rear section has been shown in a state wherein the slidable cover 704 has been moved to expose the cleaning apertures 706. Two collars 502 are also shown. The slidable cover abuts the rearmost collar 502. The wire tension adjuster or stretching device 708 is also shown on figure 8. Rotation of the wire tension adjuster 708 will tighten the wire 702, which may result in adjustment of the allowable angular movement/play of the plurality of pipe sections 204.
The system for processing of soil has been described in detail with reference to an advantageous embodiment, with certain alternatives and variations. It should be understood that the scope of the invention is not limited to such particular details. Instead, the scope of the invention is defined by the appended claims.