According to a first aspect the present invention relates to a separating device. Concrete fractions are understood to mean both concrete components, crushed concrete and a mixture thereof. The invention can also be applied for composite materials similar to concrete of relatively large and relatively small components.
A known device for crushing concrete has two crushing jaws in the form of plates, which extend converging relative to each other as seen in downward direction from the top and which are bounded on their sides by static vertical side walls. The crushing jaws and the side walls together form a hopper with a relatively large inlet opening on the top side for receiving concrete to be crushed. The upper ends of the crushing jaws are situated at a mutual distance large enough to receive chunks of concrete to be crushed. The concrete to be crushed is tipped here into the inlet opening by a conveyor belt. A drive device in the form of an eccentric for a jaw moves the upper outer end of one of the crushing jaws repetitively away from and toward the other, static, crushing jaw. The concrete is thus always pressed through the jaws moving toward each other, after which the crushing jaws move apart to allow the concrete to drop into the hopper between the crushing jaws. The one crushing jaw is then moved toward the other again in order to exert pressure on the concrete situated between the jaws. The movement of the jaw or jaws is intended to crush the concrete to be crushed with the highest possible output and press it through the outlet. The concrete is (further) crushed or ground due to the stresses occurring here between and in the pieces of concrete to be crushed. The smaller the fractions of the (partially) crushed concrete, the further the fractions drop in the direction of the outlet opening, wherein the crushing jaws define an outlet opening in the form of a gap. The outlet opening is adapted to the dimensions of a fraction to be produced and is for instance about 40 mm. The distance between the crushing jaws on their underside, with the desired size of the crushed pieces of concrete, also determines the flow rate, together with the frequency of the reciprocally moving crushing jaw and the composition of the concrete to be crushed.
A drawback of the known device is the low-value output thereof, i.e. small pieces of randomly crushed concrete (mixture), because the original components of the concrete (mixture), unhydrated cement, cement stone, sand, gravel are not separated from each other.
The present invention therefore aims to provide a separating device for concrete, with which the component parts of the concrete, such as unhydrated cement, cement stone, sand and gravel, can be better separated from each other so that a higher-value output is realized. This object is made possible by the present invention in that outlet restriction means are provided under the outlet opening to limit an outflow of crushed concrete and/or concrete fractions. This means that the mutual distance between the crusher members themselves is not the (only) restriction, but that an additional restriction is provided below the outer ends. Such a measure moreover provides the option of increasing the mutual distance between the crusher members, while this need not have any adverse effect on the fineness of the crushed concrete. The effect which hereby occurs is discussed in the following paragraph.
When the outlet opening of a separating device for concrete is relatively small, as is the case in the crushing devices known heretofore, concrete is often crushed “through the gravel” when two gravel pebbles are situated adjacently of each other directly between the crusher members close to the outlet opening, and are pressed further toward each other by the jaws. The force exerted by the crusher members is exerted on a relatively small amount of matter, whereby the contact surfaces of the matter are exposed to relatively high pressure, whereby random break lines appear through the concrete. When there is more space between the crusher members, the pressure on the matter is reduced and the pebbles moreover have sufficient space to move upward or downward between the other rubble. A consequence hereof is that the pebbles will break less easily and, as a result of the force exerted on the concrete and the relative movement of the gravel pebbles, sand and cement are pressed and scoured from the gravel pebbles. This because cement stone has a lower strength than a gravel pebble and will therefore collapse first. In the case where there is a greater distance between the crusher members, outlet restriction means, which slow down throughflow, are provided in order to hold the partially crushed/separated material between the jaws for a relatively long time. In contrast to the known crushing device, the concrete is thus not so much broken into pieces but much rather broken down into component parts of the concrete. This has the advantage that the output of the crushing process is of higher quality. This has environmental advantages, the utility of the individual elements increases, and thereby also their economic value.
A separating device, particularly for separating concrete into original components, is distinguished from crushing devices in that the separating device can be adjusted, for instance by means of adjusting means, to exert a maximum force on matter between the crusher members which is considerably smaller than that in crushing devices. Crushing devices have the purpose of breaking matter into smaller elements. It is of no importance here where breaking occurs. In separating devices of the type according to the invention it is precisely this crushing of determined components, such as for instance gravel, which is prevented. Known crushing devices are therefore not suitable as separating device of the type according to the present invention.
German patent application DE 4121797 A1 describes a device for reducing granular bulk material with two crushing devices connected in series, i.e. two crushing plates which are movable toward each other and away from each other, and a crushing roller. This document does not describe the separation into (original) components of a composite material such as concrete. Nor is an outlet restriction provided under the outlet opening between the crushing roller and the plate.
German patent application DE 10 85 401 B also describes a crushing jaw device. The outlet opening of this device is situated between a closing plate and a crushing plate. No outlet restriction is provided after the outlet opening.
The American patent document U.S. Pat. No. 4,406,416 describes a jaw crusher for crushing stones or rock. The separation of composite material is not described in this document either. The described device is not suitable for this purpose, precisely because according to the aimed result of the invention stones must be prevented from breaking. The screw conveyor under the outlet opening serves to discharge crushed rock. Because material running out of the outlet opening is collected and further transported in simple manner by the relatively large screw conveyor, and the cross-sectional area thereof is much greater than that of the output flow, the screw conveyor cannot be deemed an outlet restriction.
French patent application FR 2 832 650 A1 describes a processing device, particularly for stone, with which sharp protrusions are broken off stone in order to obtain smaller stones with a less jagged surface. This crushing device is not suitable either for preventing breakage of stones, and is thus not a separating device.
British patent application GB 2 343 472 describes a mobile recycling apparatus which, due to its dimensions alone, would not be suitable for crushing concrete. This apparatus has no outlet restriction means.
In a preferred embodiment according to the present invention the outlet restriction means comprise a rotatable drum provided under the outlet opening, wherein the mutual distance between the respective crusher members on the one hand and the drum on the other limits the outflow of crushed concrete. During crushing of the concrete by the separating device the rotatable drum can rotate in one fixed direction or in a chosen direction. The axis of the drum extends parallel here to the outlet opening formed between the lower outer ends of the crusher members and is preferably situated directly below the central axis of the outlet opening, but may also be in slightly offset orientation relative to this axis of the outlet opening. The surface of the drum can be smooth, although a relief can also be provided in the drum surface. The mutual distance between a crusher member and the drum can differ from the mutual distance between the other crusher member and the drum, which can for instance be zero.
In an alternative embodiment according to the present invention the outlet restriction means comprise a vibrating plate provided under the outlet opening at a slight incline relative to the horizontal, wherein the mutual distance between the respective crusher members on the one hand and the vibrating plate on the other limits the outflow. In the case of a slightly inclining upper surface of the vibrating plate, concrete which has been crushed to sufficient extent moves downward along the vibrating plate as it vibrates and beyond the crusher member which is located above the vibrating plate on that side of the vibrating plate and which forms an outlet restriction together with the vibrating plate.
It is preferred here that the vibrating plate forms an angle of inclination relative to the horizontal, this angle of inclination lying in the range of 1 to 20 degrees, more preferably between 1 and 15 degrees. The steeper the angle of inclination, the quicker sufficiently crushed concrete is discharged. When adjusting means are provided for the purpose of adjusting the angle of inclination, the operation of the separating device can be influenced by setting a larger or smaller angle of inclination.
The outlet restriction means can also comprise a belt conveyor provided substantially horizontally under the outlet opening, wherein the mutual distance between a crusher member on the one hand and the belt conveyor on the other forms an outlet restriction. A belt conveyor, which can otherwise have a surface assembled from (metal) elements, can transport the sufficiently crushed concrete directly to a subsequent station. In the above stated embodiments a conveyor can be provided under the restriction means.
In a preferred embodiment according to the present invention the crusher members with respective crushing surfaces are arranged converging relative to each other as seen from top to bottom. An upward force is thus generated which supports the present invention in slowing the throughflow through the crusher members. The provided funnel shape contributes toward slowing of the throughflow of the matter to be crushed and partially crushed and separated matter in the device.
Irrespective of the nature of the restricting means, the mutual distance between the respective crusher member and the outlet restriction means will be smaller than the mutual distance of the outlet opening defined by the lower outer ends of the crusher members. The mutual distance between the crusher members at the outlet opening preferably amounts to at least 100 mm. Without the outlet restriction means concrete with a diameter of less than 100 mm could leave the separating device unimpeded. For a good operation of the separating device according to the present invention, wherein the outlet opening is preferably at least 150 mm, and still more preferably at least 200 mm, a better separation of the concrete into the component parts is however conversely realized by the mutual distance between the crusher members, whereby a better sorting of the output of the separating device can be realized. When a force is realized by the crusher members such that the pressure on the contact surfaces of the crushed concrete is less than the pressure at which gravel in the concrete can break, the gravel is thus scoured clean by the surfaces of the gravel with cement stone rubbing against each other.
When the outlet restriction means form a finer filter than the outlet opening, the outlet restriction means form an obstruction to the discharge speed of at least partially crushed and separated matter, whereby the outlet opening becomes partially blocked, with the effect that the matter remains between the crusher members longer. The term filter may be interpreted very broadly and does in effect mean obstruction of a good throughflow. The cross-sectional area of the flow of matter at the outflow opening is thus greater than the cross-sectional area of the flow of matter at the restriction means.
It is further recommended that the mutual distance of the crusher members at the outlet opening is at least twice as great as the corresponding mutual distance between the outlet restriction means. The mutual distance of the crusher members at the outlet opening is preferably at least three times, more preferably five times greater than the corresponding mutual distance between the outlet restriction means. This has the effect of prolonging the residence time of matter between the crusher members.
The crusher members preferably comprise crushing plates. The crushing surfaces of the crushing plates can be slightly concave or convex. Crushing plates are simple but sturdy means by which a desired force can be exerted on the concrete to be crushed.
When at least one crusher member is provided with a relief on its surface facing toward the other crusher member, the at least one crusher member with the relief has a better grip on concrete to be crushed situated between the crusher members. This further reduces the risk of pebbles being broken during crushing of the concrete. Both crusher members can of course have such a relief.
A strong separating device can be realized when one of the crusher members is in static position. A static crusher member can be firmly secured and thereby has a relatively little chance of malfunction.
The static crusher member can comprise a surface movable in the height. Static is understood to mean more specifically that said crusher member substantially does not move toward and away from the other crusher member during the operation of the device. By moving the surface of the static crusher member upward and/or downward not only are forces exerted on the concrete situated between the crusher members in the clamping direction of the crusher members but also in a direction with a component at a right angle to this crushing direction. This increases the scouring and shearing forces, whereby the component parts in the concrete are more easily separated from each other during the crushing process. By moving the matter upward between the crusher members, for instance by means of the surface movable in the height, the feed through the device is limited, whereby a better separation of the components can be realized.
Furthermore or alternatively, spring means are preferably provided with which the static crusher member is spring-mounted in horizontal direction. When too great a force threatens to build up between for instance pebbles despite the greater mutual distance between the crusher members, the breaking of pebbles can be countered in that the static crusher member yields to some extent as a result of the spring means.
In a further preferred embodiment according to the present invention the static crusher member comprises several crusher member parts which lie one above another and are individually spring-mounted. This increases the effect intended by the spring means relative to a single, integrally spring-mounted crusher member.
It is recommended that sorting means are provided for sorting the components of the crushed concrete which have left the separating device via the outlet opening and the restriction means. The restriction means could in fact be deemed a first sorting device, although additional sorting means are intended here. The sorting means of the preferred embodiment are suitable for sorting concrete crushed by the separating device into different components such as unhydrated cement, cement stone, sand, gravel and/or chunks of concrete with a predefined coarseness, which must preferably be further crushed. Relatively large pieces of concrete can be filtered in order to be fed back to the inlet opening of the separating device.
Push back means 150 are preferably provided which drive matter situated between the crusher members in upstream direction, at least when the crusher members are not moving away from each other. In conventional crushing devices attempts are made to accelerate throughfeed by attempting to press the matter between the crusher members in the direction of the outlet opening while the crusher members move toward each other. In the separating device according to the present invention an opposite effect is however desired.
Jaw adjusting means are preferably further provided for adjusting the mutual distance and/or the orientation of one or both crusher members during operation and/or when not in operation. Adjusting means for adjusting the mutual distance out of operation will be used particularly when the quality of the input matter changes. Jaw adjusting means for adjusting the mutual distance during operation will be used particularly when the quality of the output must be adjusted, i.e. when it is determined that the original components of a concrete are insufficiently separated from each other or when (too much) breaking of gravel is ascertained in the output.
According to a second aspect, the present invention relates to a method for crushing and separating into original components of concrete, comprising tipping the concrete to be crushed into a supply opening of a separating device, crushing the concrete to be crushed using the separating device and discharging crushed concrete via transport means. According to the second aspect, the present invention has for its object to provide a method for separating concrete with which it is possible to crush and to separate the concrete into the component parts of the concrete better than with known crushing methods. According to the present invention this object is achieved in that a separating device according to the first aspect of the present invention is applied in the method. Separation of components is here understood to mean at least releasing the components from each other. The flow of matter can then optionally be divided into different flows with different components. The components are in fact separated from each other in that, at least in the case of concrete, gravel pebbles covered with cement stone are pressed against each other. This results in breakage in the weakest link, i.e. in the cement stone, in/between the unhydrated cement, in/between the sand and between these components and the gravel. When the force being exerted on the matter is sufficiently limited, the gravel itself cannot break.
In a preferred method according to the present invention the crushed concrete is transported at least by means of the outlet restriction means.
In a preferred embodiment of the method, pressure to be exerted by the crusher members on the matter between the crusher members is limited to less than 250 N/mm2. Depending on the matter supplied, this force can be set differently, in the case of concrete with relatively less strong gravel to preferably 200 N/mm2, or more preferably 150 N/mm2. This pressure can be adjusted indirectly by adjusting the force the crusher members exert on the matter, the volume between the crusher members, the mutual distance between the crusher members, and so on. The pressure referred to here is the pressure which contact surfaces of cement stone, sand and gravel exert on each other's surfaces. This prevents, or at least impedes, breaking of gravel when concrete is crushed and separated into original components, which would decrease the value of the gravel.
In the method, matter leaving the separating device is preferably sorted. The different components can be divided by means of different sorting techniques, such as for instance wind separation, cyclones, screening and the like. Sorting preferably takes place according to type of material during sorting, although it is in addition (or precisely through sorting to type) also possible to sort according to size.
The present invention will be further elucidated hereinbelow on the basis of preferred embodiments of the present invention and with reference to the accompanying figures, in which:
Finally,
Only a few embodiments of a separating device according to the present invention are shown in the figures and the above description. It will be apparent that many variants, which may or may not be self-evident to the skilled person, can be envisaged within the scope of protection of the present invention as defined by the following claims. The driving of the movable crushing plate can thus for instance be effected via hydraulic cylinders. Separate drives will then have to be provided for the horizontal and vertical component. The crushing plates can take different forms, such as for instance slightly concave or convex, and the rotation directions can be opposite to the directions indicated in the figures. The dimensions stated in the figure description must be deemed as examples. Depending on the type of concrete, the pebbles present therein can have different dimensions. The device and the method can further also be applied for separating into original components other materials which, just as concrete, comprise relatively large and relatively small components, such as mixed granulates or other mineral materials. No sorting means which sort the output of the separating device are described or shown in the description and the figures. These are however generally known means which are applied for at least partially separating components such as gravel, unhydrated cement, cement stone and sand. The rod systems with external screw thread can be replaced by other adjusting means, such as for instance cylinders. The mutual distances between the crushing plates of
Number | Date | Country | Kind |
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2004700 | May 2010 | NL | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/NL2011/050314 | 5/9/2011 | WO | 00 | 11/26/2012 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2011/142663 | 11/17/2011 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
4406416 | Tateishi | Sep 1983 | A |
5172869 | Kitsukawa et al. | Dec 1992 | A |
5397069 | Kitsukawa et al. | Mar 1995 | A |
5660337 | Falbo et al. | Aug 1997 | A |
5749530 | Nakayama et al. | May 1998 | A |
7614573 | Jean | Nov 2009 | B1 |
20040050987 | Rossi, Jr. | Mar 2004 | A1 |
20060097095 | Boast | May 2006 | A1 |
Number | Date | Country |
---|---|---|
1085401 | Jul 1960 | DE |
1085401 | Jul 1960 | DE |
8913077 | Nov 1989 | DE |
8913077 | Nov 1989 | DE |
8913077 | Dec 1989 | DE |
4121797 | Feb 1991 | DE |
4121797 | Feb 1991 | DE |
4121797 | Jan 1993 | DE |
0442309 | Aug 1991 | EP |
2832650 | May 2003 | FR |
2343472 | May 2000 | GB |
WO 2004014558 | Jul 2003 | GB |
WO 2004014558 | Jul 2003 | GB |
6015188 | Jan 1994 | JP |
06015188 | Jan 1994 | JP |
0041812 | Jul 2000 | WO |
2004014558 | Feb 2004 | WO |
Number | Date | Country | |
---|---|---|---|
20130092769 A1 | Apr 2013 | US |