FIELD OF THE INVENTION

The present invention concerns an apparatus to recover incoherent material present in a process fluid. The process fluid can derive from industrial operations that use, for example, water or similar liquids, to perform certain processes, such as, for example but not only, waterjet cutting, and that produce as a waste product the process fluid itself, mixed with incoherent material such as, for example particulate matter, granules, inert material, abrasive substances or suchlike.

The present invention also concerns a method to recover incoherent material present in a process fluid, as well as a cutting machine which uses the apparatus as above.

BACKGROUND OF THE INVENTION

Industrial processes are known in which water, or similar process fluid, is used as an operative mean to carry out certain processes which entail the dispersion of incoherent material in the process fluid.

In particular, industrial machines are known for the waterjet cutting of various materials at extremely high pressure.

Waterjet technology is a cutting process performed cold, which uses a jet of pure water or an abrasive jet of water.

The jet of pure water is used in applications to cut, in a natural way and without using abrasives, “soft” materials such as gaskets, polystyrene, plastic, paper, wood, insulating materials, concrete slabs, carpets, hides, leather, food products, etc.

The abrasive jet of water is similar to the jet of pure water but, after creating the jet of pure water, incoherent substances are inserted into the cutting head of the cutting machine, in particular abrasives (such as siliceous sands), which, mixed with the water, increase the cutting power and produce a jet able to cut “hard” materials such as metals, ceramics, stone, glass and composite materials.

In this case, incoherent materials such as particles and/or debris and/or solid residues (particulate) of the abrasive type are generated as waste material.

One disadvantage of water cutting concerns the disposal or possible recovery of the incoherent material generated by processing.

The disposal of the abrasive material represents a particularly important problem, since periodic operations are required to empty the collection tank where the process fluid normally collects. In addition to the discharge of water from the collection tank, the periodic maintenance operations also comprise the manual or mechanical extraction of the incoherent material generated. The latter can be accumulated in bins, big-bags, or other locations awaiting transport and transfer to landfills or recovery centers, which are not always located near the places where the incoherent material is generated. This procedure entails a considerable cost for companies, as well as the frequent transport of incoherent material, with the consequent environmental problems.

Mechanical systems are known to dispose of or recover the incoherent material generated and present in the collection tank. However, such systems are typically subject to wear, which entails high maintenance costs and a limited useful life. In particular, one component that is typically subject to wear is the pumping system for the process fluid containing the incoherent material. In general, in order to pump the fluid, known recovery systems use a centrifugal pump on which a filter is applied to retain part of the incoherent material, so as to prevent said material from coming into contact with the pump components. Disadvantageously, this solution does not allow to retain all the abrasive material, and the continuous contact of the material with the impeller of the pump and/or with the various components which ensure its hydraulic seal causes frequent problems of wear on the parts mentioned above.

This solution is described for example in IT UB20154174.

Other known solutions, for example the one described in US 2006/207927, provide to use centrifugal pumps that do not have hydraulic sealing elements, in which part of the process fluid can escape from the pump body to be collected in a chamber outside the pump. This solution is particularly disadvantageous in that in any case the process fluid, and consequently the incoherent material, comes into contact at least with the impeller of the pump. Furthermore, by depriving the pump of the sealing elements, significant reductions in efficiency are caused. Another disadvantage of the known solution as above is that it requires another recovery system, suitable to recover the process fluid which has flowed into the chamber outside the pump, making this solution particularly expensive.

Furthermore, the need is known to recover the process fluid that has been purified of the incoherent material in order to facilitate the natural discharge operations thereof, or to reintegrate it into the processing cycle, for example in waterjet cutting, or to reuse it in other mechanical processes in order to reduce waste and optimize available resources.

Another need is to be able to make the recovered incoherent material reusable “on site”.

There is therefore a need to implement and/or perfect an apparatus to recover incoherent material present in a process fluid which can overcome at least one of the disadvantages of the state of the art.

In particular, one purpose of the present invention is to provide an apparatus to recover incoherent material that allows to separate the incoherent material from the process fluid in order to recover at least part of the latter.

Another purpose is to provide an apparatus to recover incoherent material that allows to reuse at least part of the latter in industrial processing operations.

Another purpose of the present invention is to provide an apparatus to recover incoherent material that allows it to be installed “on site”, that is, directly associated with one or more processing machines.

Another purpose of the present invention is to provide an apparatus to recover incoherent material present in a process fluid that allows to reduce the maintenance or cleaning interventions on the apparatus, automating the steps of recycling, recovering and pumping the process fluid.

Another purpose of the present invention is, consequently, to provide an apparatus to recover incoherent material that allows the incoherent material recovered to be taken to a landfill or to specialized plants for its reuse, reducing the overall costs of its disposal.

Another purpose of the present invention is to perfect a method to recover incoherent material that is effective and that allows to automate the steps of recycling, recovering and pumping the process fluid.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages. SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

In accordance with the above purposes, the present invention concerns an apparatus to recover incoherent material present in a process fluid deriving from industrial operations performed in at least one user machine, for example an abrasive water cutting machine.

According to the invention, the recovery apparatus comprises a separation device configured to separate the incoherent material from the process fluid by means of centrifugal action.

In a preferential solution, the separation device is of the cyclone type.

According to one aspect of the invention, the separation device is provided at least with one entrance for the process fluid to be treated, advantageously tangent with respect to the oblong development of the separation device, and at least one exit to discharge the incoherent material disposed along the separation device and downstream of the entrance.

According to one aspect of the invention, the recovery apparatus comprises a pumping unit configured to remove the process fluid from a removal zone and send it to the entrance of the separation device.

Advantageously, the separation device allows to substantially obtain a complete removal of the incoherent material from the process fluid, for example water.

In this way, there is a reduction in the costs relating to the extraction, separation, recovery, reuse and/or landfilling of the incoherent material present in the process fluid to be treated and, moreover, the treated process fluid, that is, purified of the incoherent material, can be easily recovered.

The apparatus of the present invention can also comprise a selection device, downstream of the separation device, configured to select the incoherent material separated from the process fluid on the basis of its granulometry. In particular, in preferred embodiments, the selection device allows to separate at least a fine portion and a large portion of such incoherent material, which are then sent to respective collection elements. In accordance with one embodiment, the apparatus can also comprise a drying device configured to dry at least part of the incoherent material selected.

Advantageously, the recovery apparatus as above allows to obtain a reduced bulk, minimum pressure drops and a high flow rate of the process fluid to be treated, and is able to be used “on site”, that is, directly associated with one or more working and fluid jet cutting machines. In other words, the apparatus of the present invention can be advantageously supplied, or mounted, on board one or more abrasive fluid jet machines.

The present invention also concerns a cutting machine that uses a jet of process fluid provided with a tank to collect the process fluid containing at least a process fluid mixed with incoherent material produced during the cutting, and with an apparatus to recover incoherent material as described above, wherein the process fluid is water.

Advantageously, such apparatus to recover incoherent material allows to perfect the waterjet cutting machine as above, allowing to recover the incoherent material produced during the cutting and, therefore, to reuse the water used in the cutting, both in the case of a “pure” water jet and also in the case of an abrasive jet with water mixed with abrasive incoherent material.

The present invention also concerns a method to recover incoherent material present in a process fluid.

According to the present invention, the method provides to:

- remove the process fluid containing at least process fluid mixed with incoherent material from a collection zone;

- separate, in a separation device, the incoherent material present in the process fluid to be treated from the process fluid itself;

- recover the incoherent material separated from the process fluid;

- recover the process fluid purified of the incoherent material.

In preferred embodiments, the method can also provide to select, on the basis of the granulometry, the recovered incoherent material in order to recover at least a large portion and a fine portion thereof.

The method can also comprise drying at least part of the incoherent material selected.

Such method allows to optimize the energy resources available for a process by recovering the process fluid, once it has been purified of the incoherent material, and reusing at least part of the incoherent material once it has been separated from the process fluid. Such method, therefore, is particularly advantageous from the perspective of both the efficiency of the plant to which it will be applied and also of cost effectiveness.

According to one embodiment, the recovery of incoherent material provides to collect the selected portions of incoherent material separated from the process fluid in respective collection elements.

According to another embodiment, the method comprises dehydrating the fine portion of the incoherent material, that is, removing the residual process fluid by means of recovering and accumulating such fine portion of the incoherent material in a first collection element having draining characteristics.

Advantageously, using collection elements allows to speed up and facilitate the operations of disposal and/or reuse of the recovered incoherent material, and the drying thereof allows to preserve, transport and adequately store the incoherent material pending its landfilling or other intended use.

ILLUSTRATION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

- figs. 1 and 3 are schematic views of respective embodiments of a recovery apparatus in accordance with the present invention;

- figs. 2 and 4 are perspective views of the embodiments of the apparatus of figs. 1 and 3 respectively.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings.

DESCRIPTION OF EMBODIMENTS

We will now refer in detail to the various embodiments of the invention, of which one examples is shown in the attached drawings.

Some embodiments described here with reference to the attached drawings concern an apparatus 10 to recover incoherent material M present in a process fluid F.

According to a preferred embodiment, the recovery apparatus 10 is directly associated with one or more “cold” cutting machines, in particular with machines that use an abrasive water jet.

However, we do not exclude applying the recovery apparatus 10 on any other working machine whatsoever that provides to use, produce and/or eliminate process fluid F mixed with incoherent material M.

By incoherent material M, here and in the present description we mean inert material, for example abrasive, of different granulometries which is suspended or immersed in a process fluid F, for example, but not limited to, water, following industrial processes.

In particular, by incoherent material M we mean both the material originating from pure waterjet cutting of materials such as cement or suchlike, such as for example, but not limited to, solid particles, debris, or residues (particulate matter), and also abrasive material contained in an abrasive waterjet such as, but not limited to, abrasive silica sand and material released when cutting hard materials such as metals or suchlike.

In particular, such incoherent material M is recovered and collected together with the process fluid F in a collection zone 11.

In the case of waterjet cutting, as shown by way of example in fig. 2, the collection zone 11 can be a collection tank 11a generally provided under, and in correspondence with, a waterjet cutting machine (not shown).

By process fluid F we generally mean, here and hereafter in the description, water, aqueous mixtures, pure water, water with suitable additives or similar or comparable fluids.

According to the present invention, the recovery apparatus 10 comprises a separation device 13 configured to separate, by means of centrifugal action, the incoherent material M from the process fluid F.

In the specific case shown by way of example in figs. 1-4, the separation device 13 is of the cyclone or hydrocyclone type.

In particular, the separation device 13 is provided with at least one entrance 15 for the process fluid to be treated FI, provided in this case tangential with respect to the separation device 13.

By process fluid to be treated FI we mean, here and hereafter in the description, the process fluid F mixed with incoherent material M. According to one embodiment in accordance with the present invention, the separation device 13 is also provided with at least one exit 16 to discharge the incoherent material M, provided along the oblong development of the separation device 13 and downstream of the entrance 15 as above.

In particular, the discharge exit 16 is provided coaxial to the oblong development of the separation device 13.

According to the present invention, the recovery apparatus 10 comprises a pumping unit 12 configured to remove the process fluid to be treated FI from a collection zone 11 and send it to the entrance 15 of the separation device 13.

Advantageously, the tangential entrance 15, together with the thrusting action of the pumping unit 12, promotes the generation of the spiral motion inside the separation device 13. The high peripheral speed imparted, in a progressively increasing manner, to the fluid to be treated inside the separation device 13 creates a controlled vorticity such as to project the incoherent material M in suspension toward the external wall, exploiting the centrifugal force which generates a spiral-shaped flow in a downward direction toward the discharge exit 16. Consequently, the incoherent material M, since it has a greater inertia than the process fluid F (typically water), is thrust against the external walls and falls to the bottom of the separation device 13.

According to some embodiments, the separation device 13 is made of stainless steel. Advantageously, the stainless steel material allows a high resistance to abrasion following contact with the incoherent material M of an abrasive nature, and to oxidation following contact with the process fluid, for example water.

With reference to figs. 1-4, the separation device 13 has a cylindrical portion in which the tangential entrance 15 of the process fluid to be treated FI is provided, and a conical portion associated at the lower part with the cylindrical portion and in communication with the latter. In the conical portion there is provided the exit 16 to discharge the separated incoherent material M. This conical portion substantially acts as a hopper to recover the recovered incoherent material M.

According to one embodiment, the separation device 13 is also provided with an exit 21 to recirculate the treated process fluid F, the recirculation exit 21 being provided on the side opposite the discharge exit 16 and transverse with respect to the entrance 15.

Advantageously, the centrifugal force generated inside the separation device 13 is such as to thrust the process fluid F, once treated, upward, that is, toward the recirculation exit 21. By treated process fluid F we mean, here and hereafter in the description, process fluid F substantially without any incoherent material M, that is, without any solid substances whatsoever with different granulometries dispersed in the fluid itself.

With reference to the drawings, this recirculation exit 21 is provided in the cylindrical portion of the separation device 13.

In particular, the recirculation pipe 19 connects the recirculation exit 21 with a destination zone 25 of the treated process fluid F, in order to recover such fluid. The treated and recovered process fluid F can be reused in subsequent industrial workings, or it can be discharged in a natural manner. The destination zone 25 can be a waterjet cutting machine, or a water cooling system, an accumulation tank, plants or systems for industrial working, or discharge plants or systems.

With reference to figs. 1 and 3, the destination zone 25 can coincide with the collection zone 11 , substantially producing a closed circuit for the recovery of the process fluid F. For example, the collection zone 11 can be a collection tank 1 la of a waterjet cutting machine in which, during the cutting, the water released for the jet cutting itself accumulates.

According to further embodiments, the treated process fluid F can be sent to a fluidization unit 33 consisting of a series of ejectors 34 to amplify the flow rate. In particular, such ejectors 34 can be disposed in the collection zone 11 so as to force the process fluid FI to be treated toward the suction pipe 17. Advantageously, this conformation also allows to force the possible incoherent material M, which is deposited for example on the bottom of a collection tank 1 la, toward the suction pipe 17 of the apparatus 10. A recovery apparatus 10 is thus obtained which is able to continuously recycle the process fluid F, reducing energy consumption, for example relating to the use of a waterjet cutting machine, minimizing its maintenance or cleaning operations.

In addition, the fluid dynamic characteristics of the recovery apparatus 10 are sueh as to minimize the pressure drops and to obtain a high flow rate of the treated process fluid F.

With reference to the attached drawings, the pumping unit 12 is connected, through a suction pipe 17, to the collection zone 11 in which the process fluid to be treated F 1 is located.

In particular, the pumping unit 12 is connected, through a delivery pipe 18, to the entrance 15 of the separation device 13.

In a preferred embodiment, the pumping unit 12 is an anti- wear pump, in particular a peristaltic pump, which allows to prevent contact between the process fluid to be treated FI, containing the incoherent material M, and the components of the pump itself.

The peristaltic pump advantageously allows to transfer the process fluid to be treated FI containing incoherent, in particular abrasive, material M without it coming into direct contact with the internal components of the pumping unit 12, preventing premature wear of the pumping unit 12 and a consequent frequent and expensive maintenance thereof. However, other types of pumps are not excluded.

As shown by way of example in the attached drawings, the pumping unit 12 can be driven by a motor 23.

The motor 23 can be for example an electric motor or an endothermic motor.

According to one embodiment, the recovery apparatus 10 comprises one or more elements 14, 14a to collect the incoherent material M downstream of the discharge exit 16.

In particular, a first collection element 14 can be configured to drain the process fluid F, through suitable meshes, and retain the incoherent material M inside it. For example, the first collection element 14 can be a draining bag. In this way, the first collection element 14 retains the incoherent material M that has been separated, recovered and discharged by the separation device 13, and allows to dehydrate the incoherent material M itself, draining the residual process fluid F, in particular water, through its meshes.

According to one embodiment, the first collection element 14, once filled and once the incoherent material M has been dehydrated, can be replaced with a new empty first collection element 14, either manually or automatically. This solution facilitates landfilling of the recovered incoherent material M or its transport to other destinations of use.

According to one embodiment, the recovery apparatus 10 comprises a drain pipe 20 associated with the first collection element 14, on the side opposite the discharge exit 16, to channel and recover the process fluid F which flows by gravity through the second collection element 14a itself.

According to one embodiment, the recovery apparatus 10 comprises a conveyor element 27 configured to recover the process fluid F drained by the first collection element 14 and convey it into the drain pipe 20. This conveyor element 27 can have a grid-shaped conformation from the side in contact with the first collection element 14, so as to make the drained process fluid F flow into the conveyor element 27 itself.

In particular, the drain pipe 20 is configured to introduce the process fluid F drained through the first collection element 14 into the destination zone 25 of the process fluid F. With reference, by way of example, to the attached drawings, the drain pipe 20 can introduce the process fluid F drained by the first collection element 14 into the destination zone 25, exploiting the slope of the drain pipe 20 itself and, therefore, gravity.

According to one possible variant, with reference to fig. 4, the drain pipe 20 can introduce the process fluid F, drained by the collection element 14, into the destination zone 25 with the aid of a pump 32.

In other embodiments, with reference to figs. 3 and 4, the recovery apparatus 10 can comprise a selection device 30 downstream of the discharge exit 16. The selection device 30 is configured to select the incoherent material M exiting from the separation device 13 on the basis of the granulometry thereof. Such selection device 30 can preferentially have at least two stages, thus allowing to select a large portion Ml of the incoherent material M having an average granulometry greater than that of a fine portion M2 complementary thereto.

Two or more elements, first 14 and second 14a, to collect the incoherent material M can be disposed downstream of the selection device 30. In this specific case, the second collection element 14a is intended to collect the large portion Ml, having a larger granulometry, of the incoherent material M exiting the selection device 30. The first collection element 14 can instead be intended to collect the fine portion M2, having a smaller granulometry, of the incoherent material M exiting the selection device 30.

In some preferred embodiments, the recovery apparatus 10 can comprise a drying device 31, interposed between the selection device 30 and the second collection element 14a. The drying device 31 allows to dry the large portion Ml of incoherent material M, that is, the one having a higher average granulometry, before collecting it in the second collection element 14a. In this way, the large portion Ml is immediately recoverable and reusable, making the recovery apparatus 10 of the present invention particularly advantageous. In fact, once filled, the second collection element 14a can be replaced, manually or automatically, with a new empty second collection element 14a. The large portion Ml of incoherent materia! M thus selected can be recovered for further industrial processing operations (for example, abrasive waterjet cutting).

Instead, the fine portion M2 of incoherent material M exiting from the selection device 30 and collected in the first collection element 14 can be dehydrated as described previously, thus facilitating its landfilling.

In some embodiments, with reference to fig. 1, the recovery apparatus 10 comprises a discharge pipe 22 associated on one side with the discharge exit 16 of the separation device 13, and on the other with a collection element 14, 14a in order to discharge the incoherent material M inside it. In other embodiments, the discharge pipe 22 is associated on one side with the discharge exit 16 of the separation device 13, and on the other with the selection device 30 in order to discharge the incoherent material M inside it.

According to some embodiments, the recovery apparatus 10 comprises at least one discharge valve 24 disposed downstream of the discharge exit 16. In one embodiment, the discharge valve 24 can be mounted on the discharge pipe 22 in order to regulate the outflow of incoherent material M from the discharge exit 16. The discharge valve 24 can be a timed discharge valve so as to be open for a period of time that is adequate to let the right amount of incoherent material M fall into the one or more collection elements 14, 14a and/or into the selection device 30.

In particular, the discharge valve 24 can be a pneumatically driven timed discharge valve. Thanks to the presence of the timed discharge valve 24, an automatic recovery of the incoherent material M is obtained, preventing periodic maintenance and cleaning interventions and thus accelerating the recovery times of the abrasive material and of the treated process fluid F.

According to one embodiment, the recovery apparatus 10 comprises a control unit 26 configured to manage the functioning of the separation device 13, of the pumping unit 12, of the discharge valve 24, of the selection device 30 and of the drying device 31 as a function of the type and size of the incoherent material M to be recovered, the degree of recovery to be obtained and the type of process fluid F.

In particular, the control unit 26 can be configured to control and command the motor 23 of the pumping unit 12.

According to one embodiment, the control unit 26 can be configured to detect the filling of the collection elements 14, 14a by means of one or more sensors 29, 29a and to signal the need to replace them by means of sound and/or visual signals.

Such sensors 29, 29a can be weight sensors, as shown by way of example in fig. 2 or 4, or optical sensors.

According to one embodiment, the control unit 26 can be configured to regulate the timer associated with the discharge valve 24 as a function of the type of incoherent material M, the sizes of the collection elements 14, 14a and the time required to dehydrate the incoherent material M.

According to one embodiment, the control unit 26 is configured to close the discharge valve 24 in case of replacement of the collection elements 14, 14a.

According to one embodiment, the control unit 26 is configured to control and command the pumping unit 12 as a function of the desired entrance pressure and speed of the fluid to be treated FI in the entrance 15 of the separation device 13, for example , but not limited to, by means of pressure detection means 28.

The present invention also concerns a method to recover incoherent material M present in a process fluid to be treated FI, which provides to:

- remove, from a collection zone 11, the process fluid to be treated FI containing a process fluid F and the incoherent material M;

- separate, by means of centrifugal action in a separation device 13, the incoherent material M from the process fluid F itself;

- select the recovered incoherent material M in order to recover at least a large portion Ml and a fine portion M2 thereof, based on the granulometry;

- recover the incoherent material M separated from the process fluid F;

- recover the process fluid F purified of the incoherent material M.

In preferred embodiments, the removal of the process fluid FI occurs through a pumping unit 12 comprising an anti- wear pump, for example a peristaltic pump. Flowever, other types of pumps are not excluded.

According to further embodiments, the method provides to at least partly dry at least one of the selected portions Ml, M2 of incoherent material M.

According to some embodiments, the recovery of incoherent material M provides to release and collect, at regular time intervals, the incoherent material M separated from the process fluid F, and possibly selected and dried, in at least one collection element 14, 14a.

The method can also comprise dehydrating the fine portion Ml of the incoherent material M, that is, removing the residual process fluid F, by recovering and accumulating the fine portion Ml in a collection element 14, 14a having draining characteristics.

It is clear that modifications and/or additions of parts or steps may be made to the apparatus 10 to recover incoherent material M present in a process fluid F and to the corresponding recovery method as described heretofore, without departing from the field and scope of the present invention.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of recovery apparatus 10 and corresponding recovery method, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.