WO1996016770A2

WO1996016770A2 - Method and device for preparing blasting media and blasting water

Info

Publication number: WO1996016770A2
Application number: PCT/DE1995/001707
Authority: WO
Inventors: Wilhelm Schmidt
Original assignee: Abrex Oberflächentechnik Gmbh
Priority date: 1994-12-02
Filing date: 1995-12-01
Publication date: 1996-06-06
Also published as: WO1996016770A3

Abstract

The invention concerns a device for recycling blasting media and blasting water, said device having a jet nozzle (10) by means of which the blasting medium, mixed with blasting water, can be applied to an object to be blasted (12). The device further has a collector/trap arrangement (14) for a mixture of blasting medium, water and material from the blasted object, which mixture is produced at the blasted object (12). The device also has a retainer arrangement (16) for coarse particles of this mixture, a settlement area (18) for the blasting medium, above which area there is a layer (20) of blasting water in the collector/trap arrangement (14), a removal pipe (22) projecting into the settlement area (18) for the removal of blasting medium and components of blasted material, a suction or forcing pump (54) for generating a force to convey the blasting medium, and a water-removal snorkel (24) which projects into the layer of water (20) and terminates in the opening area of the removal pipe (22) in order to bring about the separation and recycling of a granulated material-water mixture by feeding water into the removal pipe (22).

Description

Method and device for the treatment of blasting media and water

The invention relates to a method and a device for the treatment of blasting media and water jet according to the preamble of claim 1.

From EP-A2-0 359 701 it is already known to provide a sink for cleaning the sand which is to be recycled as an abrasive. In this case, tubular stirring arms and a rotating sieve star are provided, which pushes coarse and sludge parts to the edge. However, this device and the method described there are only suitable for dirt particles with a significantly different consistency than blasting agent or water, is complex and consumes a lot of energy. Sludge residues can occur in inaccessible places in the device.

Blasting with blasting media, in particular sandblasting, in which dust formation is avoided by the addition of jet water, is also increasingly being used for the renovation of building walls, for facade cleaning and the like. Parts of the object to be blasted, e.g. B. color, possibly easily removable parts of the object, sand-shaped parts, but also large parts, such as wall fragments and the like.

So far, the blasting agent and the jet water have either not been recycled, so that large amounts of blasting agent and jet water are mixed as waste contaminating particles remain, or it was dried, sieved and filtered in a complex and costly manner.

The invention is based on the object of creating a closed circuit in which the abrasive and the jet water are continuously recycled.

A further object of the invention is to filter the contaminating particles as pure as possible (wall stone, dirt, paint) from the circulation.

In particular, it should be possible to retain radioactively contaminated material, which is produced, for example, when blasting media with slightly radioactive walls, so that there is no concentration of radioactive material in the circuit when the blasting media is run through several times.

An advantage of the inventive solution to the problem as described in the features of claim 1 is, in particular, that in a first collecting / collecting device there is a calm, non-turbulent water layer over the abrasive which is deposited (mixed with emitted polluting particles) trains. This blasting agent / particle-water mixture is conveyed by suction from the bottom layer of a collecting / collecting device into at least one blasting agent storage container filled with water.

Abrasive particles that have a significantly higher density than water advantageously fall relatively directly to the bottom of the abrasive container. Loading Components that have approximately the same density as water or a lower mass can be filtered out because these components, which are kept in suspension by strong water vortices, emerge from the overflow of the blasting agent reservoir together with displaced water and are concentrated on an easily replaceable filter can be, so that there is no concentration of these components at another, undesired point in the cycle.

The relatively purified water is advantageously brought back into the circuit during the blasting, but in particular when the object to be blasted is washed off.

The constituents which have approximately the density of water or are of low mass will in particular be radioactive contaminated color particles. According to the invention, these are filtered out again at least to the extent that they enter the circuit in the same circulation, so that an uncontrolled accumulation in inaccessible places is excluded.

Coarse constituents (coarser than the blasting agent) can be collected by an advantageously provided retaining device, such as a sieve, above the collecting / collecting device, so that they do not interfere in the further circulation of the blasting agent.

Floating polluting particles, e.g. Styrofoam, will float on the water layer and can be easily removed from there.

The admixture of those in the circuit which are still to be cleaned of paint particles is particularly advantageous Water when removing abrasive / particle-water mixture from the collecting / collecting device. This makes it possible for the first time that the very viscous, hardly flowable wet granulate can be pumped or sucked in. This results synergistically in the effect that the paint particles are comminuted through the conduits together with the blasting agent and are detached from any adhering sand particles so that they do not settle together with them, but instead behave according to the specific weight of the color itself.

Excess water accumulating in the blasting agent container is removed there and, after filtering into the collecting / collecting device above the area of the blasting agent removal opening, the newly arriving jet water arriving from the blasted object and already settling above the blasting agent to the desired extent added.

The filter device provided, with a filter fleece in which suspended matter particles are collected, now advantageously releases its almost completely purified water back into the collecting / collecting device to the extent necessary to keep the water level constant , so that light components floating on the water can be removed mechanically at the same place at all times. All coarse components can be removed mechanically beforehand from a sieve, which advantageously covers the collecting / collecting device.

According to the invention it is further proposed that the addition of water to improve the viscosity of the blasted material is provided in such a way that a strong addition Turbulence forms in the extraction nozzle. This can be achieved by additionally directing the water supply direction against the abrasive / particle mixture removal / discharge direction, water and sand advantageously being mixed in approximately equal amounts.

The geometry of the extraction nozzle is slightly chamfered with a covering overhang and is arranged in the collecting / collecting device so that it slopes upwards slightly. The water supply from the water extraction snorkel advantageously takes place from above into the blasting material extraction nozzle.

However, it is also advantageous to add low-viscosity fluid, in particular water, from another source into the extraction nozzle protruding into a storage container, in order in particular to cause a swirling in this extraction nozzle, which also makes it possible to set clumping components in motion. so that even removal of the blasting medium is not disturbed by it either. In this context, “thin fluid” is any fluid that has a higher viscosity than moist blasting media.

According to the invention, it is further proposed that the fluid addition which improves the viscosity of the blasted material is provided in such a way that, due to the geometry, a strong turbulence is already formed in the bleed nozzle. This can be achieved by additionally directing the water-supplying device, for example, against the blasting agent removal outflow direction, which advantageously means that sand and water can be mixed in approximately the same ratio. The removal nozzle is further proposed with such a shape that there is a slightly bevelled end edge with a covering overhang, and the removal nozzle is preferably arranged slightly obliquely upwards out of the storage container.

Water is advantageously fed into the extraction nozzle from above. However, it is also conceivable to additionally add air from below, which causes a bubbling swirl.

The water supplied can come from any source. It is conceivable to enter fresh water directly at this point, or to use process water that is already in a cycle, be it settled purified water or water contaminated with color particles.

It is also proposed to introduce low-viscosity fluid in the direction of the extraction nozzle, possibly with an adjustable distance from the extraction nozzle; to introduce the fluid into strongly curved areas of the extraction nozzle; parallel to the conveying direction in the extraction nozzle; or to provide a combination of these feeds which are controlled and provided with the desired amounts of fluid.

Further features and advantages of the invention result from the following description of a preferred exemplary embodiment with reference to the attached drawing.

It shows: 1 is a schematic diagram of the entire device, in which a sketched clinker wall is shown as an object to be blasted, and

2 is a sectional view showing the removal of the blasting medium from a storage container in which a blasting medium / water mixture (with a water content of more than 18%) is deposited,

3 shows a fluid (water) supply line in front of a siphon for removing the blasting agent, in which the distance between the end of the supply line and the siphon can be regulated,

4 shows a feed for low-viscosity fluid in a critical, sharply deflecting area of a siphon,

5 shows a feed for thin liquid fluid which extends into the removal nozzle and runs parallel to its extension in a partial area,

6a shows a device in which the devices from FIGS. 3 and 4 are used and in which the water supply is controlled with a three-way valve, and

FIG. 6b shows a device like FIG. 6a, in which the devices from FIGS. 4 and 5 are used.

SPARE BLADE (RULE 26) The device shown in FIG. 1 for the reuse of blasting agent and water jet has a blasting nozzle 10 on the left edge, with which a jet containing blasting agent and water is directed onto the object 12 to be blasted, for example a clinker wall can be tet. The blasting agent falling from the clinker wall mixed with the jet water and any particles detached from the clinker wall, e.g. B. color, dirt or sand-like constituents falls into a collecting / collecting device 14, advantageously a collecting / collecting device which tapers downwards as a container and is covered with a sieve 16.

The screen 16 advantageously has a small opening width, for example 3 mm, so that coarse components can be removed from the screen 16. Below the screen 16, a water layer 20 forms above the settling area 18 for the blasting agent mixture. Sand, which due to its higher density sinks downwards, is advantageously used as the blasting agent, this settling movement taking place relatively free of turbulence, so that components which are a little lighter than the jet water will float on a cover layer.

The blasting agent / particle-water mixture can be removed from this container of the collecting / collecting device 14, as better shown in FIG. 2, with the aid of a suction pipe or a removal nozzle 22. A region 62 is formed in this removal nozzle 22, into which the blasting agent slides out of the remaining collecting / collecting device. However, the abrasive cannot be pumped easily due to its high friction with the walls and its low viscosity 9 -

pushed or sucked under pressure. However, if water, as shown in FIG. 1, is added from a snorkel 24 above the settling area 18 from the water layer 20 of the collecting / collecting device 14, the amount of this addition being able to be regulated by a valve 44, it is possible to increase the viscosity of the now blasting agent / water mixture in such a way that it can be pumped or sucked through pipelines.

For pumping, a pump 54 is advantageously proposed, which feeds the blasting medium to a blasting medium container 26. It is also conceivable to use a compressor which pressurizes the collecting / collecting device for conveying it out, or a suction of the blasting agent / particle-water mixture (SSW) by means of a vacuum.

In the blasting agent container, the blasting agent will settle in the lower region 28 and a layer 30 of water and similarly heavy or low-mass particles will arise turbulently above it. Due to the turbulent mixing, it is now possible for the first time to also remove in a liquid jet those parts which pass through a valve 34 which are only slightly lighter or heavier than water or which have only small masses. It is also possible to deposit the fine components in a sludge layer, which can be removed to the outside through special outlets. It is conceivable to create several such water extraction openings which discharge different fractions.

The removal of larger amounts of water is possible, among other things, because the amount of water that has been added to the blasting agent is no longer required to remove the deposited blasting agent from the tank. to execute. Rather, the water is now cleaned again via a further filter device with a water filter basin 40 and a fleece filter 36. The fleece filter 36 serves, among other things, to collect the small color particles, which have approximately the density of the water, and can be disposed of together with them.

Excess water from this water filter basin 40 can either be disposed of as normal process water, which is now almost pure, or, according to the invention, can advantageously be returned to the collecting / collecting device 14 via a water supply line 38, where it can be removed by the removal snorkel 24 is removed again in relatively large quantities. However, it can also be used for the blasting agent transport in the blasting hose 64 and advantageously also for washing off the blasted object 12.

The removal snorkel 24 is advantageously arranged in a region clearly spaced from the water supply, in order to supply water with colored particles to the blasting agent through a line 52 if possible. The removal snorkel 24 can be designed as a float.

Crushing the paint particles on the pump path from the extraction nozzle 22 to the blasting agent container 26 is not a problem, since the filter fleece 36 advantageously has a pore size of 20 μ, so that crushing only contributes to the correct uniform particle size suitable for the filter.

The swirling of all particles in the blasting agent container 26 is advantageously prevented by a pouring cone 32 for wide-area input of the particles. supports, which widens the feed jet in a feed area. An agitator can be provided for support.

The same applies to the conceivable provision of a further container, a collecting container (not shown), to which the blasting agent / particle-water mixture (SSW) is supplied as storage, and in which it can be temporarily removed from the circuit. Of course, the blasting medium pressure container should also be able to be loaded with blasting medium again from this collecting container, for example by means of a pouring flap.

It is proposed to design the tip of the extraction suction tube 22 at an angle so that the blasting agent can more easily penetrate into the opening cross-section 60 from below and the base edge of the pouring cone 62 is shortened. A large surface area of the pouring cone 62 of blasting agent which has entered the suction pipe 22 and whose size can be regulated by the inclination of the removal nozzle promotes removal.

The removal of blasting agent, for example pit sand or river sand, from a storage container shown in FIG. 2 takes place in a preferred embodiment through a removal nozzle 22 which leads out of the storage container at a slight incline. The end edge 60 of the extraction nozzle is designed with a slight overhang upwards so that material sliding down from above must bypass the overhang. This will result in a pouring edge with a relatively flat angle. The upper cone of this pouring cone 62 is acted upon by water supplied by means of a water pipe 52, with already wet blasting medium - 12th

is swirled with the make-up water. This mixture of approx. 25 parts sand to 75 parts water or up to a mixture with equal proportions is pumped out through the extraction nozzle 22.

It is also conceivable to provide other thin liquid fluid instead of water. Water with low blasting agent admixtures or the use of air are also conceivable, but would then advantageously be introduced into the removal nozzle from below in order to loosen the blasting agent in the area of the cone 62. As mentioned, the base edge of the pouring cone is shortened by the inclined end edge of the extraction nozzle 60, so that a subsequent supply of blasting media is facilitated from below.

It is further proposed that the supply line 52 for the water be provided with an angle of incidence a of less than 90 °, that is to say to point against the pumping direction in the extraction nozzle, so that there is better swirling. In particular, the thin fluid fluid, e.g. B. the water, which is supplied through line 52, directed directly onto the pouring cone. In a preferred embodiment, the angle a is approximately 45 °. However, smaller angles are conceivable if a high flow rate can be achieved through a narrow cross section of the water supply line 52.

In FIG. 3, a feed line 52 for low-viscosity fluid is provided in the removal nozzle 22 in front of its mouth, the distance between the outlet nozzle mouth and the end of the feed line being adjustable in a preferred embodiment. 4 shows a mouth section of the feed line 52, which projects into a strongly curved section 24 of the removal nozzle 22 up to a part of its diameter, so that in this region, which is very susceptible to deposits, the curvature causes the greatest change in the conveying direction causes good swirling.

In FIG. 5, a mouth section 50 of the feed line 52 is oriented in a corresponding partial section of the removal nozzle 22 after a section coming almost perpendicularly from the side parallel to its extension in the conveying direction, so that, above all, the flow rate is increased .

Finally, in FIGS. 6a and 6b more than one orifice section is provided for the supply line 52, the supply of thin fluid between the orifices 46, 48 of the supply line being adjustable by a metering valve 44 and a three-way valve 42 connected downstream. 6a shows the suggestions of FIGS. 3 and 4, feeds in front of the mouth and in the region of curvature of the removal nozzle, and in FIG. 6b the suggestions of FIGS. 4 and 5, feeds parallel to the removal nozzle and combined in its area of curvature.

Finally, it is also proposed to carry out a mechanical emptying of the sieve 16 from the coarse particles which have fallen onto the sieve by means of continuously moving collecting grippers, and the removal of lightly floating components, likewise mechanically by means of the parts which push off the floating parts. A vibrating device on an inclined sieve 16 could also move parts caught on the sieve.

Claims

EXPECTATIONS

1. A process for the treatment of blasting media and jet water in which the blasting media / jet water mixture collected from a collecting basin (14) is brought into a reuse cycle after blasting a surface to be blasted, for reuse.

characterized in that the preparation of the mixture of blasting agent and water jet and contaminating particles is carried out by the following steps:

Passing the mixture through a retaining device (16) for coarse parts of the mixture,

Allowing the blasting agent / particle mixture to settle in a settling area (18) over which a layer (20) forms in the collecting basin (14), which contains jet water and unsettling suspended particles,

Conveying the deposited blasting agent / particle mixture through a removal nozzle (22) leading from the settling area (18),

whereby from the layer (20) containing water and suspended particles, liquid is guided from there into the mouth area of the removal nozzle (22), so that this water to be cleaned is used for the re-used blasting agent / particles conveyed out of the collecting device Mix is added.

2. Device for treating blasting media and jet water with a collecting basin (14) for collecting the blasting media / jet water mixture after blasting a surface to be blasted,

marked by

a retention device (16) for coarse parts of the abrasive / particle mixture for the preliminary separation of coarse particles from the abrasive / particle mixture to be prepared,

a settling area (18) for the blasting agent / particle mixture, over which a layer (20) forms in the collecting / collecting device (14), which contains jet water and suspended particles,

a discharge nozzle (22) leading from the settling area (18),

a water extraction snorkel (24) protruding into the water layer (20), which guides the liquid removed by it into the mouth area of the extraction nozzle (22), so that this water to be cleaned is reused for the blasting agent conveyed out of the collecting device / Particle mixture is added.

3. Apparatus according to claim 2, characterized in that the removed blasting agent / particle mixture (SSW) a blasting agent pressure container (26) is fed to Placing the blasting agent in a bottom area (28) and swirling the water with shredded welding particles in a layer (30) above it to remove the shredded particles with liquid removed at this location and to discharge the blasting agent from this again into a blasting hose (64 ).

4. The device according to claim 2, characterized in that the removed mixture is supplied to at least one further Be¬ container for the accumulation of blasting agent as a supply, from which the blasting agent pressure container (26) can be loaded and in which the blasting agent in the bottom region (28th ) settles and the water is swirled with sweat particles in a layer (30) above.

5. Device according to one of claims 2 to 4, gekenn¬ characterized by a water filter basin (40) with a fleece (36) on which the excess water for the cleaning of suspended particles, which have lower or approximately the density of water, is given the water from a water drain (34) in the region of the water layer (30) and / or a sludge layer of the blasting medium pressure container (26) and / or the further container and / or displacing particles from the collecting container (14) become.

6. Device according to one of claims 2 to 5, marked by an addition device (38) for the cleaned excess water from the water filter basin (40), which is arranged behind the fleece (36) Water area for adding the water in the collecting / collecting device (14) is connected.

7. Device according to one of claims 2 to 6, characterized in that the water extraction snorkel (24) is designed as a float.

8. Device according to one of claims 2 to 7, characterized in that the removal nozzle (22) is inserted obliquely upwards in the lower region of the collecting / collecting device (14).

9. Device according to one of claims 2 to 8, characterized in that the removal nozzle (22) at its mouth (60) is chamfered to form a cover covering the overhang, which reduces the blocking slipping of blasting media directly from above and the base edge of the pouring cone (62) in the discharge nozzle (22) is shortened.

10. Device according to one of claims 2 to 9, characterized by at least one feed line (52) for low-viscosity fluid, which is directed into the removal nozzle (22) in the removal direction.