MIXING MODULE AND STEAM HEATER

Abstract

A static mixing module for mixing of material includes an inlet end and an outlet end, between which a longitudinal axis extends. A plurality of angularly spaced mixing channels extendingbetween the inlet end and the outlet end, each two adjacent mixing channels being separated by an intermediate wall. At least one mixing element is provided within each mixing channel. Each intermediate wall has a uniform or an essentially uniform wall thickness (t) as measured in a plane perpendicular to the longitudinal axis. A steam heater is also disclosed which comprises said static mixing module.

Claims

1. A static mixing module for mixing of material fed through the mixing module, the mixing module comprising: an inlet end and an outlet end between which a longitudinal axis extends; a plurality of angularly spaced mixing channels extending between the inlet end and the outlet end, each two adjacent mixing channels being separated by an intermediate wall; an d at least one mixing element provided within each mixing channel, wherein each intermediate wall has a uniform or an essentially uniform wall thickness as measured in a plane perpendicular to the longitudinal axis.

2. The mixing module according to claim 1, wherein at least a major part of each intermediate wall consists of a wear resistant material comprising at least 10 percent by volume of hard particles in the form of metal carbides, metal carbonitrides and/or metal nitrides.

3. The mixing module according to claim 2, wherein the wear resistant material is a metal matrix composite material.

4. The mixing module according to claim 2, wherein said major part of each intermediate wall is located at the inlet end of the mixing module.

5. The mixing module according to claim 2, wherein at least a major part of the mixing module consists of said wear resistant material.

6. The mixing module according to claim 5, wherein said major part of the mixing module is located at the inlet end of the mixing module.

7. The mixing module according to claim 2, wherein the mixing module includes a steel portion.

8. The mixing module according to claim 7, wherein the steel portion is embedded in the wear resistant material.

9. The mixing module according to claim 1, wherein the mixing module has a circular or an essentially circular cross-section in a plane perpendicular to the longitudinal axis.

10. The mixing module according to claim 1, wherein the mixing channels extend in parallel or essentially in parallel with the longitudinal axis.

11. The mixing module according to claim 1, wherein, in a plane perpendicular to the longitudinal axis, each mixing channel has a cross-section having a basic shape of an annular sector.

12. The mixing module according to claim 1, wherein the mixing module at its inlet end includes a conical portion centered on the longitudinal axis.

13. The mixing module according to claim 1, wherein the mixing module is formed using a powder metallurgy process.

14. The mixing module according to claim 13, wherein the powder metallurgy process includes hot isostatic pressing.

15. A steam heater comprising a mixing module including an inlet end and an outlet end between which a longitudinal axis extends, a plurality of angularly spaced mixing channels extending between the inlet end and the outlet end, each two adjacent mixing channels being separated by an intermediate wall, and at least one mixing element provided within each mixing channel, wherein each intermediate wall has a uniform or an essentially uniform wall thickness as measured in a plane perpendicular to the longitudinal axis.

16. The mixing module according to claim 1, wherein the mixing channels extend at an angle of between 5° and 25° with respect to the longitudinal axis

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] FIG. 1 is a perspective view of a mixing module according to an embodiment of the present disclosure.

[0033] FIG. 2 is another perspective view of the mixing module of FIG. 1.

[0034] FIG. 3 is an end view of the inlet end of the mixing module in FIG. 1.

[0035] FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3.

[0036] FIG. 5 is a side view of the mixing module of FIG. 1.

[0037] FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 5.

[0038] FIG. 7 illustartes a steam heater including the mixing module of FIG. 1.

DETAILED DESCRIPTION

[0039] A static mixing module 1 according to an embodiment of the disclosure is shown in FIGS. 1-6. The mixing module 1 is formed in one piece and has the basic shape of a circular cylinder. Module 1 includes an inlet end 2 and an outlet end 3, between which a longitudinal axis C extends. A plurality of identical and angularly spaced mixing channels 4, for example, six mixing channels 4 being shown, are symmetrically arranged in an annular region between a center portion 8 and a cylindrical casing 10. Each mixing channel 4 extends between an opening provided in the inlet end 2 and another opening provided in the outlet end 3, such that material can be fed through the mixing channels 4 from the inlet end 2 to the outlet end 3. Each two adjacent mixing channels 4 are separated by an intermediate wall 5. Each mixing channel 4 further has an outer wall 6 of uniform thickness delimiting the mixing channel 4 in a radial direction of the mixing module 1. The outer wall 6 forms part of the cylindrical casing 10.

[0040] The intermediate walls 5 are rounded at the inlet end 2 of the mixing module 1, so that the mixing channels 4 open toward the inlet end 2 in such a way that materials to be mixed can be easily guided into the mixing channels 4. At the inlet end 2, the center portion 8 has a rounded conical portion 9 centerd on the longitudinal axis C and the intermediate walls 5 have a V-shaped front end 11 with inner portions 12 and outer portions 13. The inner portions 12 are formed as continuations of the conical portion 9, having the same slope with respect to the longitudinal axis C. As shown in FIG. 4, the conical portion 9 has an opening angle a of 90° and the inner portions 12 therefore extend at an angle of 45° with respect to the longitudinal axis C. The outer portions 13, which are closer to the cylindrical casing 10, are formed at a right angle with respect to the inner portions 12.

[0041] Downstream of the inlet end 2, each intermediate wall 5 has a uniform, or an essentially uniform, wall thickness t as measured in a cross-section perpendicular to the longitudinal axis C. This can most clearly be seen in the cross-sectional view of FIG. 6. Thus, for at least that part of the mixing module 1 that is located downstream of the inlet end 2, the wall thickness t of each intermediate wall 5 does not change in a radial direction of the mixing module 1.

[0042] The mixing channels 4 have in the shown embodiment a cross-sectional shape in the form of an annular sector with rounded corners, as can be seen in FIG. 6. Within each mixing channel 4, a mixing element 7 in the form of a sloping protrusion from the outer wall 6 is provided. Apart from the mixing elements 7, the mixing channels 4 have an essentially constant cross-sectional area downstream of the inlet end 2. In alternative embodiments, two or more mixing elements can be provided in each mixing channel. The mixing element or elements may protrude from the outer wall and/or from the intermediate wall. The mixing elements may also be helical, so as to induce a stronger rotation of the material within the mixing channels.

[0043] At the outlet end 3, the cylindrical casing 10 extends downstream of the intermediate walls 5 and the center portion 8. The outlet end may, in an alternative embodiment, have an identical or similar design as the inlet end 2, i.e. with a conical portion centered on the longitudinal axis C and mixing channels opening toward the outlet end.

[0044] The mixing module 1 is in the shown embodiment formed with a major part of a wear resistant material and a minor part of a structural steel. The minor part is here in the form of a steel core 14 embedded in the center portion 8 as shown in FIG. 4. Alternatively, the outlet end of the mixing module may form the minor part.

[0045] The mixing module 1 is according to a preferred embodimentcan be manufactured using a powder metallurgy process including hot isostatic pressing (HIP). Suitable methods of manufacture are disclosed in e.g. WO2014086655 and WO2014041027. In short, a mould or capsule is provided, defining the shape of the mixing module. A powder or a homogeneous powder mixture, i.e. a mixture of powder of at least two different compositions, is provided and filled into the mould. The mould is thereafter evacuated and sealed and the filled mould is subjected to HIP under predetermined conditions, so that metallurgical bonding of the powder particles is achieved. If one part of the mixing module is to be formed of e.g. structural steel, either as the outlet end or as an embedded part, and one part is to be formed of a wear resistant material, the structural steel part may either be formed first and used as a substrate or core when forming the wear resistant part, or the steel part and the wear resistant part may be formed together in the HIP process.

[0046] FIG. 7 shows a partially cut open steam heater 20 according to an embodiment of the disclosure. The steam heater 20 includes a mixing module 1 as described above, fitted into a pipe 21. Upstream of the mixing module 1, a material inlet pipe 22 is provided, via which material can be fed toward the mixing module 1. Furthermore, a steam inlet pipe 23 is provided, via which steam can be added.

[0047] During operation, material to be mixed with steam is fed through the material inlet pipe 22 toward the mixing module 1 in the direction of flow, as indicated by the arrows. Steam is simultaneously provided via the steam inlet pipe 23 in the direction of flow indicated by the arrows. Material and steam enter the mixing channels 4, and the mixing elements 7 trigger a rotation of the material and steam within the mixing channels 4, thus heating the material with the steam. As the material exits the mixing module 1 at its outlet end 3, it is homogenously heated. In the case where the steam heater 20 is used to heat oil sand slurry, bitumen is after heating in the steam heater 20 separated from clay, sand, water and chemicals contained in the slurry. This separation is carried out in a separate, subsequent process.

[0048] The mixing module and the steam heater according to the present disclosure may be used in various industries such as in oil and gas, pharmaceuticals, food processing, pulp and paper, etc. For example, it is suitable for applications in which a high resistance to erosive wear is desirable. However. the mixing module need not solely be used for steam heating applications, but can also be used in various other mixing operations.

[0049] Although the present embodiment(s) has been described in relation to particular aspects thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred therefore, that the present embodiment(s) be limited not by the specific disclosure herein, but only by the appended claims.