TREATING MATTER

Abstract: Matter to be treated is passed through at least two treating regions 12, 14 sequentially. In each region a bed 29, 31 of the matter is moved in a band continuously along an annular path by passing fluid through the bed along the path. The annular paths of the regions 12, 14 are concentric.

Description: This invention relates to treating matter, for example particulate and/or liquid matter. Our specification EP-B-68853 discloses apparatus for treating matter having a treating region defined by a structure including a base provided with an annular fluid inlet means, means for supplying matter to the region and for extracting treated matter means for supplying fluid to the annular inlet fluid means and means for imparting vertical and circumferential components to the flow of fluid through the inlet means for moving a bed of said matter in said region in a band along an annular path in said region as said fluid passes through said bed. We have now devised a development of the apparatus disclosed in the above-mentioned European patent specification which is advantageous in certain applications in that it increases the capacity of apparatus of a given overall size and/or provides for more efficient treatment of particular classes of matter. The invention includes apparatus for treating matter, comprising at least two treating regions, each region being defined by a structure including a base provided with an annular fluid inlet means, said annular inlet means of the regions being disposed concentrically about an upwardly directed axis of the apparatus; means for supplying matter to be treated to the region provided with the radially outer of the annular inlet means; means for enabling matter to be extracted from the region provided with the radially inner of the annular inlet means, means for transferring matter from a said region whose annular inlet means is disposed radially outwardly of that of another region to said other region; means for supplying fluid to each annular fluid inlet means; and means for imparting vertical and circumferential components to the flow of fluid through each inlet means for moving respective beds of said matter in said regions in respective bands along respective axially and radially spaced concentric annular paths in said regions as said fluid passes through said beds. The annular inlet means of said regions may be spaced axially, the axially upper of said annular inlet means being disposed radially outwardly of the other annular inlet means. Preferably, when the apparatus comprises more than two said regions, the annular inlet means of each region other than the region provided with the axially upper inlet means is disposed radially inwardly of the inlet means next above it. The invention also includes a method of treating matter in at least two treating regions each of which is bounded by a base wherein in each region a bed of matter is moved in a band continuously along an annular path above the fluid inlet means thereof by passing fluid supplied to the region through said annular fluid inlet means through the bed along said path, the annular paths of the regions being concentric and radially spaced, and wherein the matter to be treated is supplied to the region having the radially outer of said paths and extracted from the region having the radially inner of said paths, the matter being transferred from the or each region whose annular path is disposed radially outwardly of that of another region to said other region. The concentric annular paths may be spaced axially the axially upper of the annular paths being disposed radially outwardly of the other annular path or paths. Furthermore, preferably in such a method when the matter is passed through more than two regions, each annular path other than the axially upper path is disposed radially inwardly of the annular path next above it. The fluid which is passed through the beds may comprise gaseous matter which treats, or reacts with, the matter in said beds. This gaseous matter may comprise combustion gases which heat the matter in said beds during passage through said beds. Additionally or alternatively the fluid which is passed through said beds may comprise liquid matter which treats, mixes with, or reacts with the matter in said beds during passage through said beds. Additionally or alternatively the fluid which is passed through said beds may comprise air. The matter which is treated in the treating regions may comprise particulate matter and/or liquid matter. In order that the invention may be well understood, an embodiment thereof will now be described, by way of example only, with reference to the accompanying schematic drawing, in which: Figure 1 is a top plan view of an apparatus for treating matter; and Figure 2 is an aerial cross-section of the same apparatus taken along the line II-II in Figure 1. The apparatus 10 shown in the drawing comprises two treating regions 12 and 14 through which matter to be treated sequentially passes. Each region 12, 14 is bounded externally by a respective tubular wall 16, 18 and in the illustrated apparatus, both regions 12 and 14 are annular, being bounded internally by respective tubular walls 20, 22. Each region 12, 14 has a base 24, 26 provided with an annular fluid inlet 28, 30 which is spanned by an annular array of inclined vanes 32, 34. For simplicity, only a portion of the arrays of vanes is illustrated in Figure 1. However, it is to be understood that each array extends completely around the respective inlets 28, 30. The vanes which in the embodiment are fixed and arranged in overlapping relationship are inclined in order to impart vertical and circumferential components to the flow of fluid through the inlets 28, 30 for moving respective beds of the matter in the regions 12 and 14 in respective compact bands continuously along respective annular paths in the regions as indicated by arrows 36 and 38 in Figure 1 as the fluid passes through the matter in the beds. The bands are indicated at 29 and 31 respectively in Figure 2. The annular inlets 28 and 30, and thus the annular paths in the regions 12, 14 along which the beds of matter is moved, are disposed concentrically about an upwardly directed axis 40 of the apparatus. In the illustrated embodiments, the annular inlets and the annular paths associated therewith are spaced both axially and radially, with the upper of the annular inlets (and the annular path associated therewith) disposed radially outwardly of the other annular inlet (and the annular path associated therewith). This arrangement is particularly advantageous in that it enables the internal tubular wall 20 of region 12 to be formed as a continuation of the external tubular wall 18 of the region 14. The fluid which is passed through the beds of matter to move the beds continuously along the annular paths in the regions 12 and 14 is directed to the annular inlets 28 and 30 through respective supply passages 42, 44 beneath the inlets as indicated by arrows 46, 48 in Figure 2. The illustrated apparatus is provided with an inlet 49 at its upper end to enable matter to be treated to be supplied to the region 12 as illustrated by arrows 50 in Figure 2. The internal tubular walls 20 and 22 of the regions 12 and 14 are provided with respective openings 52, 54. The opening 52 enables matter to be transferred from region 12 to region 14 as indicated by arrow 56 in Figure 2, and the opening 54 enables matter to be extracted from the region 14 as indicated by arrow 58 in Figure 2. The matter extracted from region 14 exists the apparatus via outlet 60. In use, matter is supplied to the region 12 to form a bed therein which is moved in band 29 continuously along an annular path by passing fluid through the bed along that path and is treated in region 12. The cross-sectional size of the band 29 of matter being moved in region 12 depends upon the amount of matter in that region. Initially, when matter is first supplied to the region 12, the band has a small cross-section and moves adjacent the external wall 16. On introduction of further matter, the cross-section of the band increases both radially inwardly and axially upwardly such that when the matter in region 12 exceeds a predetermined amount, excess matter will exit the region 12 through opening 52, to be transferred to region 14 to form a bed therein which is moved in a band continuously along an annular path by the fluid which is passed through the bed along that path, and be treated in region 14. As with the band 29, the cross-sectional size of the band 31 of matter being moved in the region 14 depends on the amount of matter in that region. Likewise, initially when matter is first transferred to the region 14 from region 12, has a small cross-section and moves adjacent the external wall 18 of region 14. On transfer of further matter, the cross-section of the band 31 increases both radially inwardly and axially upwardly such that when the amount of matter in region 14 exceeds a predetermined amount, excess matter exits from region 14 through opening 54. Thus, it will be appreciated that once the two regions 12 and 14 contain the above-mentioned predetermined amounts of matter, supply of further matter to region 12 results in matter being transferred from region 12 to region 14 and matter being extracted from region 14. In this way a throughput of matter is achieved, the matter passing sequentially through the two regions 12 and 14 before exiting the apparatus. The above described apparatus and method are particularly advantageous for treating matter which after being treated does not automatically rise from the bed to exit from the apparatus (as is the case for example when perlite is expanded by being heated by combustion gases which are passed through the bed as described in our specification EP-B-68853). Although there is no control in how long particular matter is retained in region 12 before being transferred to region 14 nor how long particular matter is retained in region 14 before exiting the apparatus, the fact that the matter being treated is passed through two regions enables an average treatment time to be achieved. If the treatment time is particularly critical, more control over the treatment time may be achieved by modifying the apparatus to include a further region or regions like regions 12 and 14 having annular paths concentric with the annular paths provided by regions 12 and 14. Thus, for example the illustrated apparatus could be modified to have a further region provided with an annular inlet spaced axially below and radially inwardly of inlet 30 of chamber 14. In this case, it will be appreciated that matter would be transferred from region 14 to this further region and eventually exit the apparatus from the further region. The matter which is passed through the treating regions may comprise particulate matter and/or liquid matter. The fluid which is passed through the beds may comprise gaseous matter which treats, or reacts with the matter in the beds. For example, the gaseous matter may comprise combustion gases which heat the matter in the beds during passage through the beds. One particular example, is the case where the matter being treated comprises coffee beans which are roasted as they pass through the regions by combustion gases. Another example is where the matter to be treated comprises a slurry from which the liquid is driven off by the combustion gases. The fluid which is passed through the beds may comprise liquid matter which treats, mixes with, or reacts with the matter in the beds during passage through the beds. Again in this case, the matter in the beds may comprise particulate matter and/or liquid matter. For example, the liquid which is passed through the beds may chemically react with matter in the beds comprising solid particulate matter suspended or dissolved in liquid matter. The fluid which is passed through the beds may alternatively comprise air in which case the purpose of the fluid may be merely to move the matter in the beds along their annular paths. For example, the matter in the beds may comprise particulate matter and liquid matter which coats the particulate matter as both the particulate matter and liquid matter are moved along the annular paths. It will also be appreciated that a different fluid may be passed through each bed to enable different treatments to be carried out on the matter when it is in each bed. It will be appreciated from the above that by providing a plurality of treating regions through which the matter to be treated passes sequentially and in which the matter is moved along respective concentric annular paths, the path length for the matter (and thus the capacity of the apparatus) is increased for a given overall size as compared with the apparatus disclosed in our specification EP-B-68853 where only one treating region having an annular path is present. Whilst the embodiment discloses one particular arrangement of concentric paths in which two annular paths are spaced both axially and radially with the axially upper of the annular paths disposed radially outwardly of a lower annular path, it is to be understood that more than two annular paths may be provided and that these paths may be spaced only radially.

Claims: Apparatus for treating matter, comprising at least two treating regions (12,14), each region being defined by a structure including a base (24,26) provided with an annular fluid inlet means (28,30), said annular inlet means of the regions being spaced radially and disposed concentrically about an upwardly directed axis (40) of the apparatus; means (49) for supplying matter to be treated to the region provided with the radially outer of the annular inlet means; means (54,60) for enabling matter to be extracted from the region provided with the radially inner of the annular inlet means, means (52) for transferring matter from a said region whose annular inlet means is disposed radially outwardly of that of another region to said other region; means (42,44) for supplying fluid to each annular fluid inlet means; and means (32,34) for imparting vertical and circumferential components to the flow of fluid through each inlet means for moving respective beds of said matter in said regions in respective bands along respective axially and radially spaced concentric annular paths in said regions as said fluid passes through said beds. Apparatus as claimed in claim 1, wherein said annular inlet means of said at least two treating regions are spaced axially, the axially upper (28) of said annular inlet means being disposed radially outwardly of the other annular inlet means (30). Apparatus as claimed in claim 2 and comprising more than two said regions, wherein the annular inlet means of each region other than the region provided with the axially upper inlet means is disposed radially inwardly of the inlet means next above it. A method of treating matter in at least two treating regions (12,14) each of which is bounded by a base (24,26) wherein in each region a bed of matter is moved in a band (29,31) continuously along an annular path above the fluid inlet means (28,30) thereof by passing fluid supplied to the region (12,14) through said annular fluid inlet means (28,30) through the bed along said path, the annular paths of the regions being concentric and radially spaced, and wherein the matter to be treated is supplied to the region (12) having the radially outer of said paths and extracted from the region (14) having the radially inner of said paths, the matter being transferred from the or each region whose annular path is disposed radially outwardly of that of another region to said other region. A method as claimed in claim 4, wherein the annular paths of the regions (12,14) are spaced axially, the axially upper of said annular paths being disposed radially outwardly of the other annular path or paths. A method as claimed in claim 5, wherein the matter is passed through more than two regions and wherein each annular path other than the axially upper path is disposed radially inwardly of the annular path next above it. A method as claimed in any one of claims 4 to 6, wherein said fluid which is passed through said beds comprises gaseous matter which treats, or reacts with, the matter in said beds. A method as claimed in claim 7, wherein the gaseous matter comprises combustion gases which heat the matter in said beds during passage through said beds. A method as claimed in any one of claims 4 to 8, wherein said fluid which is passed through said beds comprises liquid matter which treats, mixes with, or reacts with the matter in said beds during passage through said beds. A method as claimed in any one of claims 4 to 9, wherein said fluid which is passed through said beds comprises air. A method as claimed in any one of claims 4 to 10, wherein said matter which is treated in said treating regions comprises particulate matter. A method as claimed in any one of claims 4 to 11, wherein the matter which is treated in said treating regions comprises liquid matter.

Inventors: DODSON, CHRISTOPHER EDWARD
Applicants: MORTIMER TECHNOLOGY HOLDINGS LIMITED
Application year: 1988
Main classification: B01J8
IPC codes: A23N12, B01J8