NL8520210A - CYCLONE SEPARATOR. - Google Patents

Description

IT 8 52 02 1 0 VO 9239 -1-

Cyclone separator.

The invention relates to a cyclone separator for separating dense components of a fluid mixture from less dense components thereof, which separator is of a type, comprising an axially extending separating chamber 5 with feed means around the mixture at one end. with a tangential current component, which separation chamber is provided with an axially disposed overflow discharge at said one end and which separation chamber has a generally chamfered shape, with a relatively large cross-sectional dimension at said one end and a relatively small cross-sectional dimension at an axially located underflow drain at the end of the separation chamber opposite said one end, during operation the more dense component is directed towards the underflow drain in such a manner that an inner axially located core of the less dense compo-15 n graft, which is subjected to a differential pressure at least over a large part of its length, causing it to flow to the overflow drain.

According to one aspect of the invention, a cyclone separator as described above is characterized in that the feed members are defined by a portion of the separation chamber and at least one feed channel communicating with said portion, said portion which is part of the separation chamber, which is in the same longitudinal position as the or each feed channel, and the or channel has a profiled configuration. A particular form of profile according to the invention is a substantially involute form, which serves to supply the fluid in a spiral path.

In another form, the or each feed channel has inner and outer profiles viewed in the axial direction of their separator. The outer profile extends from a first point, where it meets the periphery of the above section of the separation chamber. At least the inner protrusion of the inner profile extends from a second point in which the inner profile or said protrusion thereof meets the periphery, the outer profile being characterized in that a first vector T, which is the location of a given point 1520210 -2- of the outer profile and located in a plane perpendicular to the said axis, the origin of which is in the first point, is such that when the value of the vector T increases, an angle Θ between the vector T and that tangent to the circumference and passing through the first point, it never decreases significantly and never becomes less than 0.1 radially negative; the cross-sectional area perpendicular to the flow direction contracts in the flow direction.

It has been found that the outer profile is more important than the inner profile. In a preferred embodiment, however, the inner profile 10 is characterized by a second vector U, which describes the location of a pole point of the inner profile and the origin of which lies in the second point, such that when the value of the vector U increases, an angle between the vector U and that tangent to the circumference and passing through the second point never decreases significantly and never decreases less than 0.52 radially negative, at least for magnitude values of the vector U.

It has been found that with profiled feeds according to the invention it is not necessary to provide more than one feed opening.

In another aspect, the invention provides a cyclone separator, as described above, wherein an end wall of the separation chamber, over which the overflow drain communicates with the separation chamber, has a curved configuration such that, viewed in axial section, it is concave or is convex.

According to another aspect of the invention, there is provided a cyclone separator as described above, wherein the overflow discharge is in the form of a conduit which extends through an end wall of the separation chamber and extends into the separation chamber.

The invention will be described below by way of example only with reference to the accompanying drawings, in which: Fig. 1 is a cross-sectional view of a separator constructed in accordance with the invention; FIG. 2 is a sectional view generally taken on the line II-II of FIG. 1;

Figures 3 and 4 show other embodiments of an end wall of the separating chamber according to Figure 1; Fig. 5 shows another embodiment of the overflow discharge for the separator according to Fig. 1; Fig. 6 shows a detailed axial cross-section of the feed members of a separator constructed according to the invention; FIG. 7 is a view similar to that of FIG. 6, however showing preferred feed channel profiles; and FIG. 8 is a partial axial view of a modified feed channel.

The separator 10 comprises a separating chamber 12 with three coaxially arranged separating chamber portions 14, 16, 18 of cylindrical configuration. These have the diameter and length d ^, 1 ^, respectively; d ^, 1 ^; and d ^, 1 ^. The section 14 has a larger diameter than the section 16 and the section 18 has a smaller diameter than the section 16. As described in the patent application PCT / AU83 / 00028, a flow restrictor (not shown) can be provided at the outlet 15 of the cylindrical section 18 are present, but in this case the discharge end is shown as being provided by an underflow discharge 24 from the cylindrical portion 18. A chamfered section 17 may be present between the portions 14 and 16. Although the section 16 shows a first section of a parallel-sided shape followed by a chamfered section, it is practically possible to design the section 16 to have a constant chamfer along its length.

Separation chamber section 14 includes an involute supply pipe 20, which opens into a side wall of the separation chamber at a supply opening 23. At the centerline of the separation chamber section 14, there is an overflow discharge 25 leading to an axial overflow pipe 27. Such as indicated in Figure 2, the involute feed pipe 20 coils around the circumference of the separation chamber portion 14 and exhibits a gradually decreasing cross-sectional area as the pipe approaches the opening 23. The pipe 20 and the opening 23 can have a rectangular cross section.

In operation, the separator 10 generally operates in accordance with known practice in that the fluid mixture supplied through the feed pipe 20 to the separation chamber is subjected to a centrifugal action, which causes the separated liquid components to be expelled, on the one hand from the drain 24 and on the other side via the drain 25. Therefore, the material with the most dense phase flows to the underflow drain 24 in a uniform cross-sectional flow around the wall of the separation chamber while the lighter phase has a central core 40 which is subjected to a differential pressure action which expels the fluid therein from the overflow drain.

It has been found that when using the involute-shaped pipe 20 it is possible to use only a single opening 23, while hitherto a number of supply openings were present. These have led to the drawback that, more particularly when rows of separators 10 are to be mounted together, the mounted installation is relatively complex. Therefore, because only a single supply pipe is present, the number of pipe connections to be made is reduced. Furthermore, it has been found that the involute-shaped pipe 20 simplifies the separating action since the incoming liquid mixture has already been separated by the effect of the centrifugal action when the mixture travels a spiral path in the separating chamber 14.

The separation chamber 12 may be constructed somewhat in accordance with the teachings of Australian Patent 47105/79, the contents of which are incorporated herein into the description to form part thereof. In Australian Patent 47105/79, the separation chamber is described as a chamber with the following dimensional relationships: 10 «12 / d2« 25 25 0.04 <dj2 ^ 0.10 0.1 «d0 / d2« 0.25 30 dl > d2 d2> d3 where A ^ is the total cross-sectional area of the inlet inlet provided by the inlet opening 23, d ^ is the diameter of the overflow-8520210 ft -5-outlet 25 and the remaining terms have meaning, such as described above. Furthermore, in Australian patent application no. 84713/82 discloses a variant of the construction having the same parameters as described above, except for the ratio d ^ / d ^, 5 which in that case is specified to be less than 0.1.

Barriers constructed in accordance with this variant can also be adapted to be used in accordance with the invention. In general, the separator according to the invention can be successfully characterized in that the ratio 1 / dd is at least equal to 10. Furthermore, in separators intended for separating relatively small amounts of a less dense liquid, such as oil, from relatively large amounts of a more dense liquid, such as water, the d / d ratio is in the range of 1.5 to 3.0, such as, for example, 2.0.

However, it has been found in practice that it is not necessary to adhere to the above-described range of overflow discharge dimensions.

Referring now to Fig. 6, a feed profile according to the invention is shown in more detail. Here, the separator feeder 20 is shown as comprising a feeder channel 80 along with a portion of the separator separation chamber, which is longitudinally adjacent thereto. In this regard, although the separator shown in FIG. 1 has been described as having three separate portions with successive diameters in succession, it is generally not essential that the separator be constructed such as, for example, each may have a generally chamfered configuration extending from a large diameter end at the overflow drain to a smaller cross section end at the underflow drain. Channel 80 is shown as a channel with an outer profile 82 and an inner profile 84. Here, the diameter D of the cyclone separator, as shown in Figure 6, corresponds to the diameter d ^ in Figure 1 since the feed channel 80 (as well as in the case of the construction of FIG. 1), with the separation chamber at its largest diameter end communicating with it.

Channel 80 is considered to extend from a point, generally indicated by reference 85, to 8520210-6 inside the separation chamber. Location 85 is determined as a point beyond which, calculated in an inward direction toward the separation chamber, the flow of feed liquid cannot be described by simple flow equations. More specifically, the 5 points. 83, 87 on the outer and inner profiles, aligned with location 85, in which, if the profiles extended therefrom in parallel relationship outwardly, the separator would operate substantially in the same manner as in the case that the profiles were continued in the profiled configurations defined according to the invention. By the term "extend outward" is meant an extension of the respective profile, which substantially touches the meeting point of the respective profile. From the respective points 83, 87 on the respective outer and inner profiles, the profiles extend inwardly in a spiral manner to meet the peripheral surface 86 of the separation chamber. The places where the profiles meet the periphery 86 are indicated by the letters "C" and "E", respectively. In practice, although the profile 84 has been indicated as joining the perimeter 86 by a continuation of the profile inwardly until it meets the perimeter 86 at the point "E", it is often more simple and more effective for mechanical reasons to complete the connection between profile 84 and perimeter 86 by providing a rounded portion 84a (indicated by a dotted line).

Preferably, the inner and outer profiles generally satisfy the following equations: 1a) & <*) <2 TT + oc, (b) 35 <OC <Ij5, where nD is the length of the outer profile 82 of the feed channel is, viewed in the axis direction of the separation chamber, D is the diameter of the portion of the separation chamber with the circumference 86 applying. This profile length is that extending between points "C" and 83. is the length of the inner profile 84, viewed in the axis direction of the separation chamber. This profile length is that which extends between 35 points "E" and 87.

Generally, the outer profile 82 is such that the vector T, which defines the location of a given point on the outer profile, and 8520210 -7- is located in a plane perpendicular to said axis and whose origin is at the position "C" is such that as the size of the vector T increases, the angle Θ between the vector T and a tangent 92 at the circumference 86 passing through the point "C" never decreases sharply and never less than -0.1 becomes radial for all values of T less than η.

(d) Similarly, a vector U describing the location of a given point on the inner profile 84 and the origin of which is located at the point "E" is such that as the value of the vector U increases, the angle octuses the vector U and a tangent 93 to said circumference, and which tangent passing through the point "E" never decreases and never becomes less than -0.52 radial, for all values of the vector U less than o, at least for significant values of the vector U. By a significant value of the vector U it is meant that in the vicinity of the point "E" the vector ü cannot be determined in connection with any rounding of the inner profile, such as described above.

The cross-sectional area of the channel 80, measured in a radial and axial plane passing through the point where the inner profile 84 actually ends (point "E" or the extreme part of the section 84a as appropriate) is preferably determined by: 2 0.04 <4 A / π D <0.1

It is also preferable that between the constants η and α the following relationship holds: α <η <2ir + α

The described relationship between the constants α and η is most suitable when, relatively speaking, the separator has a maximum diameter, which is relatively more than the diameter of the under-30 current drain. However, where this ratio is relatively smaller, such as less than 3, it may be preferable to impose greater restrictions on the relative values of the constants α and η. The following may then be suitable: D / d * 3 35 α <η <2ir + α, and 0.35 <α <2.

-8-

Here, d represents the undercurrent drain diameter, corresponding to the diameter d ^ in Fig. 1.

Referring now to FIG. 7, in a construction according to the invention, the angle β, measured about the center line of the separator 5 between points "C" and "E", was 86 °. The inner profile 84 terminated in a curved portion 84a which joined the circumference 86, this portion having a curvature of approximately 0.5 mm and extending about 110 ° about the center line of the separator from the point "C".

In this case, it was found that the following mathematical relationship applied to the description of profiles 82, 84: r0 * 0.5 D + 0.0143 D Zq1'4 ♦ 0.0057 DZ ^ '8 + 0.00157 D Z02 8 + 0.00286 D Z04'5 15 ri = fl; 5 D + 0.0714 D Zj2 + <^ 00714 DZ ^ + 0.0143 D + 0.00714 D Zj5 where r ^ is the distance from the centerline of the separator to a certain point of the outer profile 82, r is the distance from the center-line of the separator to a certain point on the inner profile 84,

Zq is the angle, calculated from line 91, connecting the center line of the separator and point "C", clockwise around the center line of the separator to a point of the outer profile 82 and Z ^ the corner, counted from line 100 in the right direction to a defined point of the inner profile 84. These equations, which generally describe profiles 82, 84, can hold for angles Zq, Z ^ in the range 0 ° <Z <150 ° 0 0 °> Z ^> 60 ° or at least in the range 30 24 °> Z.> 60 °

The channel 80 may have a rectangular cross-section, such that the long sides extend parallel to the centerline of the separator and have a length W and the short sides are in planes perpendicular to the centerline of the separator 35 stand and have a length t. In this case the following relations may apply: 8520210 -9- t x W = A ^ and D / 35 <t <D / 6.

In general, W would be greater than t.

Fig. 8 shows a further modification of the separator according to the invention, wherein the supply channel 80 is indicated as a channel which extends with its average flow path 93 for liquid flowing therein at an angle to the center line 95 of the separator rather than perpendicularly on it, as shown in Fig. 1.

In this case, the centerline 93 of the channel 80 is at an angle to the centerline in the region of 80 ° <P <95 °.

Where the channel has a rectangular cross section, it is preferred that it has such a rectangular cross section over at least a length qD, where q is less than a.

It is clear that here all angles are expressed in radians unless otherwise specified.

The described separator feed configuration can be easily applied when more than one channel 80 is present.

In this case, the total cross-sectional area of all 20 channels, measured in the radial direction of the separator via the respective points "E", should be equal to the area A, so that where it occurs in a formula tx W = Aj_, to be replaced with A ^ / n, where n is the number of channels 80. It is further noted that not all channels need to be identical. More specifically, when they are not identical, the total area A is to the lengths and widths. the supply channels at the relevant cross sections are related as follows:

Et x W = A ,, where t and W are respectively the width and length of the nth channel.

It has been found that the separator described has particularly good operating properties when separating small amounts of oil from larger amounts of water.

Fig. 3 shows a modification of the separator of FIG. 1.

Here, the end wall 50 of the separation chamber section 14, at the overflow drain 25, has a concave shape. In Fig. 4, according to a further modification, the end wall 50 is shown as a wall of convex shape when viewed in axial section. Fig. 5 shows an 8520210-10 further modification, the overflow supply 25 consisting of a pipe 27 with a portion 27a extending through the wall 50 (which in this case is shown as a linear wall in axial section) and into the separation chamber 14 stretches for a short distance.

While designing the separator feeders with the described configurations allows only a single feed to be used, the described configurations can also be used advantageously when more than one feed is present.

The term "involute" is used herein to describe a curve, which is the locus of the end of a section of a wire unwound from a ground circle. The inner and outer profiles of the or each raceway, as described, generally consist of involute curves. However, each profile may be provided with unified sections defined by unified involute curves of respective defining ground circles of different diameters, or the projected starting points on the respective ground circles may be spaced from one another in the circumferential direction are located apart.

The described construction has been brought forward for illustrative purposes only, and within the scope of the invention, as defined in the appended claims, many modifications can be made therein.

8520210

Claims (15)

1. Cyclone separator for separating more dense components of a fluid mixture of less dense components thereof, which separator is of a type, comprising an axially extending separating chamber with feed means at one end for supplying the mixture with a tangential flow component, which separation chamber is provided with an axially disposed overflow drain at said one end and the separation chamber has a generally chamfered shape, with a relatively large cross-sectional dimension at said one end and a relatively small cross-sectional dimension at a axially disposed undercurrent outlet at the end of the separation chamber opposite said one end, during use the denser component is directed towards the undercurrent outlet such that it includes an inner axially located core of the less dense component, which extends over at least a substantial portion of the len their size 15 is subjected to a differential pressure through which it flows to the overflow drain, the feed members being defined by a portion of the separating chamber and at least one feed channel communicating with said portion, said portion being that portion of the separating chamber is in the same longitudinal position as the or each raceway, the or raceway having inner and outer profiles when the separator is viewed in axial direction, the outer profile extending from a first place where the profile the periphery of said part of the separation chamber and at least the inward projection of the inner profile extends from a second place, wherein the inner profile or its projection meets the circumference, which outer profile is characterized therein, that a first vector T, which shows the location of a certain point of the outer profile b describes and is located in a plane perpendicular to said axis 30, the origin of which is located in said first point, is such that as the size of the vector T increases, the angle Θ between the vector T and that perimeter tangent extending through said first point never decreases sharply and never becomes less than 85202010 -12- radially, the cross-sectional area perpendicular to the flow direction generally contracting in the flow direction. Cyclone separator according to claim 1, wherein the inner profile is characterized by a second vector U, which describes the location of a specific point of the inner profile and the origin of which is located in said second point, which vector is such that when the size of the vector U increases, the angle between the vector U and that perimeter tangent extending through said point never decreases significantly and never decreases below -0.52 radians, at least for significant values of the vector YOU. Cyclone separator according to claim 2, wherein the feed members are characterized in that when the size of the first vector T increases, the angle Θ never decreases significantly and never decreases below -0.1 radially for all values of the vector T less than n ^, and that as the second vector U increases, the angle £ never decreases significantly and never decreases less than -0.52 radially at all values of the vector U, less than a ^, at least at significant values of the vector U , where (c) G> c <^ <2lf + oC 20 id) 0.35 <oc <considering the length of the outer profile of the feed channel in the axis direction of the separation chamber, D the diameter of the said part of the separation chamber, the length of the inner profile of the feed channel, viewed in the axis direction of the separation chamber, is measured from a first point where the outer profile meets the circumference of the associated portion of the separation chamber and is measured from e and second point in which at least one inward projection of the inner profile meets said outline 30. Cyclone separator according to claim 3, wherein: (e) 0.04 <4 A / ir D2 <0.1 where A ^ is the cross-sectional area of the channel or the combined cross-sectional area of all said channels if more then one channel is present, the or each cross-sectional area being measured in a plane substantially perpendicular to the feed channel flow 8520210-13 and intersecting the terminus of the inner profile. Cyclone separator according to claim 4, characterized in that (f) α <η <π + α The cyclone separator according to claim 4 or claim 5, wherein the 5 or each channel has a rectangular cross section over at least a length qD for q <α, the cross section being present over at least a length Wn and a width t, wherein (g ) Σ tx W = A., and η ni (h) D / 35 <t <D / 6 10 where Wn is the length of the cross section of the nth channel and t is the width of the nth channel. Cyclone separator according to claim 6, wherein the sides of the or each cross section with the length W are generally centered in the axis direction of the separator and those with the width t are generally perpendicular to the center line of the separator centered. The cyclone separator according to claim 7, wherein W> t. Cyclone separator according to any one of claims 1-8, wherein the or each channel extends at a respective angle relative to the centerline of the separator, viewed perpendicular to this axis, the respective angle p between said centerline and the mean feed flow direction for the liquid mixture when allowed through a respective feed channel, at the point where the mean flow path intersects said respective channel cross section, where area A ^ is measured equals 25 (j) 80 ° <p <95 ° where the angle p is determined such that for values thereof, less than 90 °, the liquid flow to the separation chamber during operation, along said flow path, has a movement component directed in the direction from the. end with the largest dia-30 meters to the smallest diameter end of the separation chamber. The cyclone separator according to any one of claims 1-9, wherein D / d> 3, wherein d is the diameter of the underflow drain. A cyclone separator according to any one of claims 1-9, wherein D / d 4 3 35 α <η <2π + α, and 0.35 <α <2. 8520216 -14- Cyclone separator according to any one of the preceding claims, wherein the or each supply channel has a substantially involute form. 13. Cyclone separator according to any one of claims 1-12, wherein the or each supply channel has an outer profile with a substantially involute shape. 14. Cyclone separator for separating more dense components from a fluid mixture of less dense components thereof, which is a separator of the type having an axially extending separator chamber with feed ends for feeding one end. the mixture having a tangential flow component, which separation chamber includes an axially disposed overflow discharge at said one end and which separation chamber has a generally chamfered shape with a relatively larger cross-sectional size at said one end and a relatively small cross-sectional size with an axially disposed underflow drain at the end of the separation chamber opposite said one end, during operation the more dense component is directed to the underflow drain such that it is an inner axially located core of the less dense component comprising at least about 20 z Some of its length is subjected to a differential pressure through which it flows to the overflow drain, the feed members being defined by a portion of the separating chamber and at least one feed channel communicating with said portion, wherein said portion being that portion of the separation chamber that is in the same longitudinal position as the or each feed channel, the or each feed channel having inner and outer profiles when viewed in the axial direction of the separator, the outer profile extending from a firstly, wherein the profile meets the periphery of said portion of the separation chamber and at least the inward projection of the inner profile extends from a second place, wherein the inner profile or said projection thereof extends the circumference encapsulates the outer profile characterized in that a first vector T, which represents the plaa ts of a given point of the outer profile and is located in a plane perpendicular to said axis, the origin of which is located in the first point, such that as the size of the vector T increases, the angle Θ between the vector T and that peripheral 6520210 -15 tangent extending through said first point is in the range 0 to 0.1 radial, the cross-sectional area perpendicular to the flow direction in the generally contracts in the direction of the current. 5 Cyclone separator according to claim 14, wherein the inner profile is characterized by a second vector U, which defines the location of a particular point of the inner profile and the origin of which is located in the second point, which vector is such that when the value of the vector U increases, the angle between the vector U and that peripheral tangent 10 extending through said point is in the range 0 to 0.52 radial. 8520216