CA2804656C

CA2804656C - Bulk cleaning system

Info

Publication number: CA2804656C
Application number: CA2804656A
Authority: CA
Inventors: Ferdinand Doppstadt
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-08-27
Filing date: 2010-08-27
Publication date: 2018-05-01
Anticipated expiration: 2030-08-27
Also published as: DE112010005823A5; RU2013108171A; WO2012025071A1; RU2571112C2; EP2608888B1; CA2804656A1; EP2608888A1

Abstract

The invention relates to an arrangement (10) for cleaning contaminated bulk material. lt comprises a pick-up and conveying device (12, 14, 16, 22, 29, 34) for picking up and conveying the contaminated bulk material within the arrangement (10). In addition, a mechanical separation unit (19) for mechanical separation of the bulk material and/or sludge comprising a feed (40) and mixing device (18) is provided for feeding and mixing support grains and water to the contaminated bulk material. Furthermore, a screening device (25) with a vibrating screen (24) is comprised for separating coarse constituents.
in particular support grains. A centrifuge (28) for separation of contaminants from the bulk material, a up-current classifier (30) for upward streaming dissolved suspended solids out of the bulk material, and dewatering means (32) for separating the cleaned bulk material from water therein are provided.

Description

=
Bulk cleaning system Technical Field The invention relates to an arrangement for cleaning contaminated bulk material comprising:
a) a pick-up and conveying device for picking up and for conveying the contaminated bulk material within the arrangement, b) a mechanical separation unit for mechanical separation of the bulk material and/or sludge comprising a feed and mixing device for feeding and mixing of support grains and water to the contaminated bulk material, c) a screening device with a vibrating screen for separating coarse grained components, in particular support grains, d) a centrifuge for separation of contaminants from the bulk material, e) a up-current classifier for upward streaming of dissolved suspended solids out of the bulk material, f) dewatering means for separating the cleaned bulk material from the water therein, Prior art Bulk material, in particular sand, granulates or gravel, is often used as a filter material, for example in sewage treatment plants. Due to the fitterim2, the bulk material is contaminated. In road construction or in the oil industry bulk material is also used, which is contaminated in many different ways. Contaminated materials to which the present invention is applied to also include oil slurries. Often the dirt or contamination can only be separated from the bulk material very difficultly by using chemicals. In doing so causes high costs for cleaning. Alternatively, the contaminated bulk material is not used anymore at all and is only disposed.
Different arrangements for cleaning contaminated bulk or comparable materials are known.
The German patent DE 40 34 227 C2 describes a method for preparation of deposits, in particular of sediments, more particular of sediments when dredging bodies of water, of excavated material or the like, in which the material to be treated is classified and cleaned from contaminants in successive stages. The recovered sediments enter a screen with a high-frequency vibration. The passed material is fed to a log washer and then passes into a screen cyclone which, together with a washing drum and a vibrating classifier provides a first separation stage. In a second separation stage, organic and inorganic components are feed to a cyclone system, which feeds the deposition of sand through a dense medium separator via a vibrating dewatering means to a sand storage.
The German utility model DE 298 24 791 Ul also discloses an arrangement for sand separation by density. Fine bubble air is bubbled through the sand mixture.
This sand storage can take over the task of an upstream sand separator.
EP 0 613 722 Al describes a method and a device for the separation of water and solids, in particular for the recovery of reusable sand. The contaminated sand is placed in a collecting main sump. After supplying water the sand is transferred in a screening device by means of a conveyor device, thereby separating it from large solids. The remaining =

water-solid mixture is fed via a second conveyor device to a hydro cyclone, and then to a fluidization separator. The remaining separation of the sand from the water is carried out by a dewatering device.
DE 198 10 866 Al describes a system for processing a mixture of fine materials with mineral, organic and aqueous fractions by using demineralization. Core of the system is a rotary table having a feeder for the fine material mixture directed towards the center of the rotary table. The fine material mixture is centrifuged by the rotation of the rotary table and is collected in a collecting device. Further treatments of the collected liquids and slurries follow after the demineralization.
The publication METHA - first large scale treatment plant for treating harbor sediments concerns the treatment of sediments in flowing waters. The separation of the contaminated silt from sand and other components is carried out in three steps: a pre-separation by rotating drum screens causes a coarse separation of impurities.
For further cleaning, the mixture is then processed by hydro classification. An up-current separator then separates the contaminants from the sand. Dewatering of the sand is carried out by dewatering screens.
The patent DE 199 07 513 Cl discloses a method for cleaning contaminated granular materials by attrition, i.e. by stirring in a water slurry.
DE 41 40 845 1 describes a method and a device for removing contaminants from contaminated soils. By a high pressure water jet, the contaminated soil is exploited and then processed in a classifier device into individual particle fractions. The final cleaning is carried out in a flotation device for separating the liquid from the solid components.
The patent application DE 196 21 892 Al discloses a device for in-situ cleaning of sand, for example, sand boxes, sand beaches, etc. The sand is cleaned on site by a washing process and subsequent classification. The cleaning system consists of several system components mounted to a mobile unit.

=
= 4 US 2004 0082 828 Al describes a method for decontaminating of soil containing inorganic contaminants. In a first step inorganic impurities which are contained in the form of particles in a coarse fraction are removed by means of a vibrating chute. In a further step the inorganic impurities which are contained in particulate form in an intermediate portion are removed by means of a spiral chute. Finally, the inorganic contaminants in particulate form, which are contained in a fine fraction, are separated by means of a gravity separator. By this method the inorganic contaminants in the coarse fractions, intermediate fractions and fine fractions are eliminated as far as possible.
A drawback of the known arrangements for cleaning of contaminated sand is that in many cases the result is not sufficiently well enough. Often leftovers of the contaminants adhere to the sand. Currently, such contaminations can be separated from the sand with chemicals at best, such as solvents. The use of chemicals is not only expensive, but can also affect the environment.
Disclosure of the Invention Therefore, object of the invention is to avoid the above and other existing disadvantages of prior art and to provide an environmentally-friendly device that even allows the cleaning of very strong contaminated bulk, for example bulk contaminated with oil residues.
According to the invention the object is achieved in that the arrangement for cleaning contaminated bulk material of the type described in the beginning comprises g) a steam generator processing the bulk material with steam.
The invention is based on the principle that the bulk material is cleaned with hot steam under high pressure. In doing so an efficient removal of in particular greasy contaminants is possible. The effectiveness of a steam cleaning depends primarily on the temperature and the pressure of the steam jet. In a hot steam cleaning, temperatures over 300 C are =
= 5 usually produced. The cleaning of contaminated bulk material by hot steam relies solely on mechanical cleaning stages which, in contrast to the use of chemicals, are environmentally friendly.
The arrangement for the cleaning of bulk material consists of mechanical components, which are arranged and combined such that the result of the cleaning is optimal without burdening the environment excessively. The arrangement consists of a plurality of processing stages. The respective material is transported by conveyor belts from one processing stage to another processing stage.
In a first processing stage support grains together with water are added to the contaminated bulk material in the feed and mixing device. By the added support grain the contaminants are crushed, shot up or dissolved into smaller components.
Instead of support grains, a first high pressure water generator can generate hot steam.
The hot steam is supplied to the feed and mixing device with high pressure. The arrangement can also be chosen such that both, support grains as well as hot steam under high pressure are supplied to the bulk material. By this measure, the separation of the contamination from the bulk material is considerably improved by the hot water jet forces and the swirling support grains.
In a second processing stage, the bulk material, support grains and water mixture is transported to a vibrating screen. A second high pressure water generator is provided for the screening device. In doing so hot steam under high pressure is applied to the contaminated bulk material on the vibrating screen. For example, the contaminated bulk material is exposed to hot water from water nozzles. One or more water nozzles can be pivoted during this process. The hot water jet speeds up the screening process. The grains of the bulk material, which fit through the openings of the screen, are more quickly flushed through and returned to the feed and mixing device. Oversize or large contaminants can be filtered out and removed, for example, by a conveyor belt.
Thus.
they are extracted from the further washing process.
In another particular embodiment, there is the possibility of adapting the openings of the vibrating to be variable in size. Thereby, the grain size which is to pass through the screen can be selected.
In a third processing stage, the present mixture of the second processing stage is fed to a centrifuge. The centrifuge separates a large part of the bulk material from water and contaminants due to their different density. The separated water with the contaminants dissolved therein is passed, for example, into an intermediate container.
In a fourth processing stage, the bulk material with the remains of contaminants falls into an up-current classifier disposed under the centrifuge. According to its functional principle the up-current classifier separates bulk material from suspended solids. The suspended solids are washed out by water and are also led into the intermediate container.
The washed out bulk material from the up-current classifier is fed to a vibratory dewatering means in a fifth processing stage. The dewatering means dehydrates the bulk material so that the bulk material can be removed from the arrangement by a conveyor belt and can be conveyed to a dump. Water which is separated in this procedure also flows into the intermediate container.
Practically all substances which are added to the cleaning process of this arrangement are separated and, with the exception of the contaminant, can be reintroduced into the process. Therefore, the arrangement provides a particularly environmentally friendly cleaning of contaminated bulk material.
A further advantageous embodiment of the inventive arrangement for cleaning contaminated bulk material is obtained in that a device is provided for dewatering of sludge produced by the cleaning. This device for dewatering of sludge can be added to the arrangement as a sixth processing stage. The contaminants, suspended solids and process water passed into the intermediate container are pumped down via a pumping station to a sludge press. In the sludge press water is separated from the remaining ingredients, i.e. contaminants and suspended solids. The so cleaned water is reintroduced to the bulk material cleaning process. The pressed sludge cake can be disposed of In another embodiment, the inventive arrangement for cleaning contaminated bulk material is adapted to be mobile. Sewage treatment plants do not require a continuous cleaning of bulk material. Especially for small plants the cost for such a cleaning arrangement is not worthwhile. Therefore, the mobility of the arrangement provides the ability of bringing the arrangement for cleaning contaminated bulk material to its site of operation at any time. The costs for such a facility, for example, can be shared by smaller communities.
Preferably, the arrangement for the cleaning of contaminated bulk material is formed as a unit. By this measure, it can be manufactured in a compact manner and thus is applicable in practically any location.
Since the contaminated bulk material often constitutes substantial quantities, transport costs to the cleaning arrangement are quite high. To achieve a wide range of applications in different locations without having to disassemble the arrangement for a transport, the arrangement is adapted to be mobile with a transport unit. The transport unit can be configured, for example, as a trailer on which the inventive arrangement is largely permanently installed. In this way, the arrangement can be quickly moved anywhere.
Accordingly, in one aspect the present invention resides in an arrangement for cleaning contaminated bulk material comprising: a) a pick-up and conveying device for picking up and for conveying the contaminated bulk material within the arrangement, b) a mechanical separation unit for mechanical separation of the bulk material and/or sludge comprising a feed and mixing device for feeding and mixing of support grains and water to the contaminated bulk material, c) a screening device with a vibrating screen for separating coarse grained components, d) a centrifuge for separation of contaminants from the bulk material, e) an up-current classifier for upward streaming of dissolved suspended solids out of the bulk material, 0 dewatering means for separating the 7a cleaned bulk material from the water therein, g) a steam generator processing the bulk material with steam, h) a first high pressure water generator for supplying pressurized water to the mixture of support grains and contaminated bulk mater to clean the bulk material with high pressure, and i) a second high pressure water generator is provided for the screening device for jetting the contaminated bulk material on the vibrating screen with hot water and/or steam under high pressure.
Further embodiments and advantages will be apparent from the subject matter of the dependent claims, and the drawings with the corresponding descriptions.
Brief Description of the Drawing Fig. 1 shows in a three-dimensional view a schematic sketch of an inventive arrangement for cleaning contaminated bulk material.
Fig. 2 shows in a three-dimensional view a schematic sketch of the feed and mixing device of the inventive arrangement.

Fig. 3 shows in a three-dimensional view a schematic sketch of the up-current classifier of the inventive arrangement.
Preferred Embodiment In Fig. 1 an inventive arrangement for the cleaning of contaminated bulk material is assigned with the reference numeral 10. The arrangement is a unit on a trailer 11 for a not shown truck, whereby the assembly is mobile. Wheels 13 of the trailer 11 can be seen to some extent.
The contaminated bulk material is filled into a funnel 12 adapted as an intake. The contaminated bulk material falls through the funnel 12 onto a conveyor belt 14. 16, 22, 29. 34. The conveyor belt 14, 16, 22. 29, 34 is composed of several components, and transports the contaminated and subsequently cleaned bulk material as well as the contaminants between the various processing stages. Via the conveyor belts 16 support grains are supplied to the contaminated bulk material on the conveyor belt 14.
This mixture passes into a mixing device 18 of a mechanical separation unit. A
first high pressure water generator 20 jets his hot jet of water on the mixture of support grains and contaminated bulk material. By the added support grain, the contaminants are crushed, shot up or dissolved into small components. Alternatively, the bulk material can also be cleaned only with hot steam under high pressure.
The conveyor belt 22 below the mixing device 18 transports the dissolved mixture of contaminated bulk material, support grains and water to a vibrating screen 24 of a screening device 25. A second high pressure water generator not visible in this figure generates one or more hot water jets and/or steam with which the contaminated bulk material is blasted on the vibrating screen 24 for acceleration of the screening process.
Openings 26 of the vibrating screen 24 are variable in their size in order to separate different grain sizes. The size of the openings 26 is, in particular, selected so that the =

support grains are separated and fall from the vibrating screen 24 onto the conveyor belts 16. From there they are reintroduced to the process. This means they are added to the contaminated bulk material for mixing via the conveyor belt 14.
From the vibrating screen 24 the contaminated bulk material is now supplied to a centrifuge 28 by not shown pump station. In the centrifuge 28 a large part of the bulk material is separated from water and impurities. Another part of the screened material is deposited at a location 31 via the conveyor belt 29. L-shaped blocks 33 are used as boundary and prevent that contaminants end up under the machine.
The separated water with amounts of contaminants is introduced into a not shown intermediate container. The bulk material with the remains of contaminants falls into an up-current classifier disposed underneath the centrifuge 28. Due to its functional principle the up-current classifier 30 separates the bulk material from suspended solids.
IS The suspended solids are washed out by water, and are also led to the intermediate container. The bulk material cleaned in this way is flushed out of the up-current classifier 30 and fed to a dewatering means in the form of a vibrating dewatering device.
In the vibrating dewatering device more water is removed from the bulk material.
Subsequently, the clean bulk material is transported via the conveyor belt 34 and accumulated at a location 36 for further use.
Fitz. 2 shows in a detail drawing the mixing device 18 together with the first high pressure water generator 20 in a larger scale as in Fig. I. In this embodiment the mixing device 18 comprises a euboid-shaped frame 38, which provides a supply 40 adapted as a funnel on the upper side. The mixture of contaminated bulk material and support grains is ground by the hot water jet and/or steam of the high pressure water generator 20. In this way the mixture is dissolved and falls onto the conveyor belt 22, which finally conveys the mixture to the vibrating screen 24. Below the conveyor belt 22 is a collection container 42. The collection container 42 collects material and water, which does not pass on the conveyor belt 22.
Fig. 3 shows the up-current classifier 30 in an enlarged detail view. The contaminated bulk material is introduced in the up-current classifier 30 which is also located in a cuboid-shaped frame 44. The numeral 46 refers to the edge of the up-current classifier 30 and the numeral 48 refers to the interior space of the up-current classifier 30. Water is flown from below into the interior space 48 of the up-current classifier 30 so that debris 5 particles lighter than the bulk material stream upwardly and are washed away with the water over the upper edge 46.

=

Reference Numerals arrangement (for cleaning contaminated bulk material) 11 trailer 5 12 funnel 13 wheels 14 conveyor belt 16 conveyor belt 18 mixing device 10 20 high pressure water generator 22 conveyor belt 24 vibrating screen 25 screening device 26 openings 28 centrifuge 29 conveyor belt 30 up-current classifier 31 location 33 L-shaped blocks ?() 34 conveyor belt 36 location 38 cuboid-shaped frame 40 funnel 42 collection container 44 cuboid-shaped frame 46 edge of up-current classifier 48 interior of up-current classifier

Claims

We claim:

1. An arrangement (10) for cleaning contaminated bulk material comprising:
a) a pick-up and conveying device (12, 14, 16, 22, 29, 34) for picking up and for conveying the contaminated bulk material within the arrangement (10), b) a mechanical separation unit (19) for mechanical separation of the bulk material and/or sludge comprising a feed (40) and mixing device (18) for feeding and mixing of support grains and water to the contaminated bulk material, c) a screening device (25) with a vibrating screen (24) for separating coarse grained components, d) a centrifuge (28) for separation of contaminants from the bulk material, e) an up-current classifier (30) for upward streaming of dissolved suspended solids out of the bulk material, f) dewatering means for separating the cleaned bulk material from the water therein, g) a steam generator processing the bulk material with steam, h) a first high pressure water generator (20) for supplying pressurized water to the mixture of support grains and contaminated bulk mater to clean the bulk material with high pressure, and i) a second high pressure water generator is provided for the screening device (25) for jetting the contaminated bulk material on the vibrating screen (24) with hot water and/or steam under high pressure.

2. An arrangement (10) for cleaning contaminated bulk material according to claim 1, characterized in that a device for dewatering of sludge produced by the dewatering means during the cleaning is provided.

3. An arrangement (10) for cleaning contaminated bulk material according to claim 1 or claim 2, characterized in that the arrangement (10) is adapted to be mobile.

4. An arrangement (10) for cleaning contaminated bulk material according to any one of claims 1 to 3, characterized in that the arrangement is formed (10) as a unit.

5. An arrangement (10) for cleaning contaminated bulk material according to any one of claims 1 to 4, characterized in that openings (26) of the vibrating screen (24) are adapted being variable in size.

6. An arrangement (10) for cleaning contaminated bulk material according to any one of claims 1 to 5, characterized in that the arrangement is adapted to be mobile with a transport unit.

7. An arrangement (10) for cleaning contaminated bulk material according to any one of claims 1 to 6, wherein said coarse grained components comprise support grains.