GB2357049A

GB2357049A - Arrangement in moving crusher

Info

Publication number: GB2357049A
Application number: GB0029783A
Authority: GB
Inventors: Juha Oranen
Original assignee: Roxon Oy
Current assignee: Roxon Oy
Priority date: 1999-12-08
Filing date: 2000-12-07
Publication date: 2001-06-13
Also published as: GB0029783D0; FI4856U1; FR2802122B3; FIU990498U0; FR2802122A3; DE20020845U1

Abstract

A moving crusher comprising a dust removal unit. The dust removal unit comprises at least one duct (12) and an electric filter (13), the duct (12) being arranged to lead dust from the site of dusting to the electric filter (13) acting as a dust separator. The dust removal unit and the crusher are both arranged movable such that the dust removal unit moves along with the crusher as it moves.

Description

2357049 ARRANGEMENT IN MOVING CRUSHER The invention relates to an

arrangement in a moving crusher, the arrangement comprising means for reducing dusting, said means and the crusher both being arranged movable such that the means for reducing dust- ing move along with the crusher as it moves.

Dusting is a severe problem in moving crushers. For reducing dust ing in a moving crusher, a solution has been previously disclosed, wherein a dust removal apparatus is arranged at the front end of a conveyor belt for re turning the dust in the air above the belt on to the material conveyed on the belt. The solution utilizes a pneumatic cleaner and mechanical filters that are sensitive to humidity and easily get choked. Solutions are also known wherein dusting is reduced by means of water jets. However, water jets do not work in the winter in temperatures below the freezing point. Under such conditions, the crushed pile of material also freezes and becomes lumpy.

The object of the present invention is to provide a solution for efficient removal of dust in a moving crusher.

The arrangement of the invention is characterized in that the means for reducing dusting are composed of a dust removal unit comprising at least one duct and an electric filter, the duct being arranged to lead dust from the site of dusting to the electric filter acting as a dust separator.

The essential idea of the invention is to remove dust at the site of dusting in a moving, crusher. Dust is removed with a dust removal unit comprising at least one duct for leading dust to the electric filter acting as a dust separator. The idea of a preferred embodiment is that there are several ducts for leading dust, and the electric filter is placed so as to optimize the dimensions of the ducts. The idea of a second preferred embodiment is to use the space between the conveyer and a conveyer cover as the duct for leading dust. The idea of a third preferred embodiment is to arrange the electric filter as a suspending and easily detachable unit.

An advantage of the invention is that it allows dust to be removed from the process, whereby it does not remain in the crushed material thereby causing damage. Furthermore, dust removal becomes extremely efficient, and the structure of the apparatus operates reliably and is relatively simple. A sus pending and easily detachable unit is easy to install in a moving crusher and is also easily detachable, for instance for transportation.

In the following the invention will be described in greater detail in 2 the attached drawing, which shows schematic side views of some solutions of the invention.

The figures show two moving crushers. A first crusher carriage la acts as a primary crushing plant, from which the crushed material is applied to a second crusher carriage Ib acting as a secondary crushing plant. The first crusher carriage l a comprises a feeder 2 to which the material to be crushed, such as rock, is applied. A crusher 3 for crushing the material is arranged after the feeder 2. The crusher 3 may be for example a jaw crusher or any other crusher type known per se. The crushed material is screened with a screen 4, and the underflow of the screen 4, i.e. material that is crushed sufficiently fine, is conveyed with a conveyer 5 to the second crusher carriage 1b for further processing. The overflow of the screen 4, i.e. too large material pieces, is re turned to the crusher 3 to be crushed again. The first crusher carriage la is arranged movable for example by a chain track 6. For the sake of clarity, the figure does not show the power units, control cabin or other structures in any greater detail, since they are fully obvious to persons skilled in the art.

The second crusher carriage 1 b is also a moving crusher arranged movable by a chain track 6. The second crusher carriage 1 b comprises a con veyer 7 for conveying the material fed to its lower end to a screen 8 at the up per end. The underflow of the screen 8, i.e. material that is crushed sufficiently fine, is led to a crushed material pile 9 in accordance with arrow A. The over flow of the screen 8, i.e. too large material pieces, is applied to an auxiliary crusher 10 in accordance with arrow B. The auxiliary crusher 10 is for example a gyratory crusher or another crusher type known per se. The material crushed with the auxiliary crusher 10 is conveyed with an auxiliary conveyer 11 to the front end of the conveyer 7, and is then further conveyed with the conveyer 7 to the screen 8. The power units, control cabin or other structures of the sec ond crusher carriage 1 b are not shown in any greater detail, since they are fully obvious to persons skilled in the art.

Both the first crusher carriage la and the second crusher carriage 1 b comprise the arrangement of the invention for removing dust. The moving crushers comprise ducts 12 for leading dust from sites of dusting to an electric filter 13. The sites of dusting typically include places where material falls or is dropped. Underpressure is generated in the ducts 12, i.e. the dust is sucked to the electric filter 13. The electric filter 13 is preferably placed so as to allow optimization of the lengths of the ducts 12. The ducts 12 are used to lead dust 3 to the electric filter 13 for example from three or four sites of dusting in such a way that the ducts 12 do not become too long and the pressure loss inside the ducts 12 too high.

In the first crusher carriage 1 a, the electric filter 13 is placed in con- nection with the crusher 3, and in the second crusher carriage 1 b it is placed in connection with the screen 8. However, the placement of the electric filter 13 is optional. A solution is shown for the second crusher carriage 1 b in which the space between the conveyer 7 and a conveyer cover acts as the duct for mov ing dust from the site of dusting to the electric filter 13. Herein, dust is prefera bly sucked in the travel direction of the conveyer 7, i.e. from below upwards in the figure.

The electric filter 13 is most preferably a unit to be suspended in the crusher carriage 1 a or 1 b by means of a bucket loader, for example. Further more, the electric filter 13 is preferably easily detachable from the crusher car riage 1 a or 1 b for transportation or transfer. Further, the dust removal appara tus preferably has a modular structure, whereby it is easily mountable to vari ous moving crushers for example as a retrofitting.

The electric filter 13 is based on ionization, the voltage level used being typically about 60 M The voltage level may vary between 10 and 100 kV, for example. The polarity of the electric filter in respect of ground can be selected according to the need, i.e. it may be positive or negative. The operat ing costs of electric filters 13 are significantly lower compared with for example fibre filters, since the problem of becoming choked, common in fibre filters, does not exist is electric filters. Dust filtered with an electric filter 13 is easily utilizable for further processing, and, overall, the apparatus remains very clean. An electric filter 13 naturally also comprises dust holding and discharge equipment, which are not shown in any greater detail in the figure, since they are fully obvious to persons skilled in the art.

The figure and the related description are only intended to illustrate the inventive idea. The details of the invention may vary within the scope of the claims.

4

Claims

1. An arrangement in a moving crusher, the arrangement compris ing means for reducing dusting, -said means and the crusher both being ar ranged movable such that the means for reducing dusting move along with the crusher as it moves, c h a r a c t e r i z e d in that the means for reducing dusting are composed of a dust removal unit comprising at least one duct (12) and an electric filter (13), the duct (12) being arranged to lead dust from the site of dusting to the electric filter (13) acting as a dust separator.

2. An arrangement as claimed in claim 1, c h a r a c t e r i z e d in that there are several ducts (12) and the electric filter (13) is placed so as to optimize the dimensions of the ducts (12).

3. An arrangement as claimed in claim 1 or 2, c h a r a c t e r i z e d in that, the moving crusher comprises a conveyer (5, 7, 11) having a conveyer cover on top of it, the space between the conveyer (5, 7, 11) and the conveyer cover being arranged as a duct for leading dust from the site of dusting to the electric filter (13).

4. An arrangement as claimed in any one of the preceding claims, c h a r a c t e r i z e d in that the voltage of the electric filter (13) is below 100 kV.

5, An arrangement as claimed in any one of the preceding claims, c h a r a c t e r i z e d in that the electric filter (13) is arranged as a unit to be suspended and easily detached.

6. An arrangement as claimed in any one of the preceding claims, c h a r a c t e r i z e d in that the structure of the dust removal unit is modular.