REDUCED VELOCITY TAILINGS DISTRIBUTOR

Abstract

A reduced velocity tailings distributor is provided that has been designed to create a sheet flow of tailings, thereby allowing for greater sedimentation and fines capture closer to the discharge points of the distributor.

Claims

1. A tailings distributor, comprising: a flow splitter comprising a main conduit having a feed inlet for receiving a tailings feed, a first conduit leg and a second conduit leg, each conduit leg extending from the main conduit for splitting the tailings feed into a first tailings stream and a second tailings stream, each conduit leg having an outlet; a first intake elbow and a second intake elbow connected to the outlet of first conduit leg and the outlet of second conduit leg, respectively, the first intake elbow configured to direct the first tailings stream to the right of the flow splitter and the second intake elbow configured to direct the second tailings stream to the left of the flow splitter; a first spigot manifold comprising a conduit having a first end and a second end, the first end connected to and in fluid communication with the first intake elbow, and a second spigot manifold comprising a conduit having a first end and a second end, the first end connected to and in fluid communication with the second intake elbow; each spigot manifold having at least one spigot attached thereto and an exit elbow connected to and in fluid communication with the second end.

2. The tailings distributor of claim 1, wherein the flow splitter is generally y-shaped.

3. The tailings distributor of claim 2, wherein the first and second intake elbows are 90 elbows.

4. The tailings distributor of claim 1, wherein each spigot manifold has two spigots.

5. The tailings distributor of claim 4, wherein the spigot closest to the intake elbow is configured upwardly.

6. The tailings distributor as claimed in claim 5, wherein the spigot is configured upwardly 25.

7. The tailings distributor as claimed in claim 1, wherein the discharge elbows are 90 elbows.

8. The tailings distributor as claimed in claim 1, wherein the discharge elbows further comprise at least one internal flow restrictor.

9. The tailings distributor as claimed in claim 1, further comprising: a first pontoon and a second pontoon attached to the under portion of the first spigot manifold and the second spigot manifold, respectively.

10. The tailings distributor as claimed in claim 9, further comprising: a third pontoon attached to the under portion of the flow splitter.

11. The tailings distributor as claimed in claim 9, wherein the pontoons comprise a hollow tube having sealed ends.

12. The tailings distributor as claimed in claim 10, wherein the pontoons comprise a hollow tube having sealed ends.

13. The tailings distributor as claimed in claim 9, wherein the pontoons are attached to the spigot manifolds off-center and closer to the exit elbows than the inlet elbows.

14. The tailings distributor as claimed in claim 9, wherein the pontoons are comprised of pipe sealed at both ends and filled with foam to prevent infiltration of tailings.

15. The tailings distributor as claimed in claim 10, wherein the pontoons are comprised of pipe sealed at both ends and filled with foam to prevent infiltration of tailings.

16. The tailings distributor as claimed in claim 10, further comprising: a forth pontoon attached to the under portion of the flow splitter.

17. A method for building a sand dump from extraction tailings comprising sand, fines and water, comprising: providing a first sheet flow of the extraction tailings down a first section of a sloped beaching area such that a substantial portion of the fines is captured by and deposited with the sand to form a first sand/fines lift; and allowing the water to drain and collect at the downstream end of the sloped beaching area.

18. The method as claimed in claim 17, further comprising: providing a second sheet flow of the extraction tailings down a second section of the sloped beaching area once the first sand/fines lift is formed such that a substantial portion of the fines is captured by and deposited with the sand to form a second sand/fines lift and allowing the water to drain and collect at the downstream end of the sloped beaching area.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Referring to the drawings wherein like reference numerals indicate similar parts throughout the several views, several aspects of the present invention are illustrated by way of example, and not by way of limitation, in detail in the figures, wherein:

[0020] FIG. 1 is a top plan view of a reduced velocity tailings distributor constructed in accordance with the principles of the present disclosure.

[0021] FIG. 2 is a perspective view of a pontoon used to support a low velocity tailings distributor of the present disclosure.

[0022] FIG. 3 is a side cross-sectional view schematic of a sand dump operation of the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor. The detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

[0024] One embodiment of a reduced velocity tailings distributor 100 is shown in FIG. 1. In this embodiment, tailings distributor 100 comprises a Y-shaped flow splitter 110 which receives a single flow of extraction tailings into substantially circular feed inlet 111 of main conduit 114 and discharges two separate flows of tailings therefrom to a first conduit leg 112 and second conduit leg 112, each conduit leg having an outlet 113 and 113, respectively. Connected to and in fluid communication with first and second conduit legs 112 and 112 are first intake elbow 120 and second intake elbow 120, respectively, each intake elbow having a first end and a second end, each intake elbow being attached to its respective conduit leg at its first end. In one embodiment, the first and second intake elbows are readily detachable from their respect conduit legs.

[0025] In one embodiment, the cross-sectional areas of the openings of outlets 113, 113 are substantially equal to the cross-sectional area of the opening of inlet 111. Thus, the flow velocity discharging from each outlet 113, 113 can be reduced to about 50% of the velocity of the single flow of tailings entering the inlet 111 where the volumetric flow rate through the inlet 111 and both outlets 113, 113 is substantially the same. In one embodiment, the junction of conduit legs 112, 112 to main conduit 114 may be contoured to reduce the occurrence of slurry buildup.

[0026] First intake elbow 120 is connected to and in fluid communication with first spigot manifold 130 and second intake elbow 120 is connected to and in fluid communication with second spigot manifold 130. In one embodiment, first and second intake elbows 120, 120 are 90-degree elbows. Use of 90-degree intake elbows may further reduce the velocity of the tailings and spreads the tailings feed equally to the two spigot manifolds 130, 130. It is understood, however, that the angle of the intake elbows can vary, depending upon the angles of conduit legs 112, 112 relative to main conduit 114.

[0027] Each spigot manifold 130, 130 is comprised of a first spigot box 140, 140 and a second spigot box 142, 142, respectively. First spigot boxes 140, 140 each have a spigot 141, 141, respectively, and are configured upwardly approximately 25 degrees to reduce the efficiency of the boxes since the flow is at its highest rate when the first spigot boxes are reached. Second spigot boxes 142, 142 each have a spigot 143, 143, respectively, and are configured level to the ground so that the second spigot boxes will distribute approximately the same amount of tailings feed as the first spigot boxes. The remaining tailings feed will be discharged out of discharge elbows 144, 144. In one embodiment, the discharge elbows 144, 144 are 90 elbows. In one embodiment, discharge elbows 144, 144 further comprise internal flow restrictors 146, 146, respectively, such as baffles, valves, nozzle, spoons, orifices, plates, which are inserted at or near the ends of the discharge elbows to reduce the velocity of the tailings feed exiting therefrom.

[0028] Thus, the tailings distributor 100 lowers the velocity of the tailings feed and thereby reduces the cutting problem observed when using single point distribution by open-ended pipes. Further, when the tailings feed is specifically oil sand extraction tailings, tailings distributor 100 will prevent segregation of the accumulated fines clays from the coarse sand.

[0029] In one embodiment, reduced velocity tailings distributor 100 further comprises pontoons 148 and 148, which pontoons elevate spigot manifolds 130, 130, respectively. As used herein, a pontoon means any device, which may comprise a hollow tube, that prevents the tailings distributor from sinking and allows the tailings distributor to glide across tailings formations or lifts built by the deposition of the tailings. The pontoons provide buoyancy to allow the distributor to float on the base tailings deposit. Pontoons 148, 148 may be welded, etc. directly to spigot manifolds 130, 130, respectively, and are generally positioned off-center and closer to the discharge elbows than the intake elbows. Further, pontoons 148, 148 are configured to prevent the spigot manifolds from sinking. In one embodiment, the manifolds are elevated approximately 6 feet or 2 meters. It has been shown that if the spigot manifolds 130, 130 are kept too close to the ground, they will quickly become buried under their own feed. Thus, by raising the spigot manifolds and, optionally, building a back dyke under the elevated left and right spigot manifolds, the manifolds can operate for longer periods of time without becoming buried with coarse sand.

[0030] A third pontoon, center pontoon 148, elevates flow splitter 110. Pontoon 148 may also be welded directly to flow splitter 110 and is configured to prevent the flow splitter 110 from sinking. Pontoons 148, 148, 148 also allow for easy movement of tailings distributor 100 once the tailings feed has been evenly distributed to the desired pour height, e.g., approximately six feet or two meters in one embodiment. Tailings distributor 100 is designed such that the distributor can be easily dismantled into three pieces for easy maneuvering and quick advances once the desired pour height has been reached. In particular, the intake elbows 113, 113 can be readily separated from flow splitter legs 112, 112, respectively. Because pontoons 148, 148 are positioned off-center, as described above, the intake elbows will always be on the ground so that a dozer can hook into the intake elbow and advance each of the spigot manifolds 130, 130. The pontoons act as skids on the sand to aid in the advancement of the spigot manifolds. Similarly, center pontoon 148 will also act as a skid over the sand to aid in the advancement of flow splitter 110.

[0031] A perspective view of a typical pontoon of the present invention is shown in FIG. 2. Pontoon 248 comprises a length of pipe 250 which has been cut at an angle on both ends 252, 254. Typically, the angle of the cuts are each 45-degrees, however, it is understood that other angle cuts could also be used. In one embodiment, the pontoons may be filled with foam so as to prevent water or solids infiltration.

[0032] In one embodiment, the spigot manifolds are made from 60 feet lengths of 24-inch diameter pipe made of carbon steel. The inlet elbows are also 24 inches in diameter and may be made of carbon steel with a chromium carbide overlay. Thus, the feed is equally split in both directions, i.e., left for approximately 75 ft and right for approximately 75 ft, thereby covering a cell area of approximately 200 ft or 60 metres. The pontoons can be made from 60-inch diameter pipe with a 12-foot base and 45-degree angles at each end to form a skid. The ends of the pontoon pipe are capped with sheets of steel plates and filled with expansion foam to prevent the pontoons from filling with sand or water.

[0033] The low velocity tailings distributor of the present invention also allows for the pouring of tailings to form a tailings deposit or sand dump for reclamation without having to dry dyke an area. Thus, there is a huge cost saving when using the low velocity tailings distributor of the present invention. FIG. 3 shows one embodiment of a method for building a sand dump from extraction tailings comprising sand, fines and water derived from a mined ore extraction operation by using a low velocity tailings distributor, such as a distributor of the present invention.

[0034] FIG. 3 is a side cross-sectional partial transparent view schematic of a tailings deposition method of the present invention. In one embodiment, the tailings are oil sand extraction tailings, which are typically 50% water and 50% solids by weight. The solids fraction can be further defined as being either fine or coarse solids. Typically, the solid fraction contains 80% coarse solids (defined herein as solids greater than 44 microns) and 20% fines (defined herein as solids equal to or less than 44 microns) by weight. A sloped area or beaching area 172 is provided for building the sand dump 170 which may have a collection basin 174 at the far end for collecting drained water and fines 176 which have not been trapped in the coarse solids (primarily sand) present in the extraction tailings.

[0035] The extraction tailings 160 are supplied by low velocity tailings distributor 100, whereby the left and right spigot manifold is elevated to 72 at the base of the 24 spigot pipe by means of pontoons (only one pontoon, pontoon 148 shown) and a back dyke may be pushed under the elevated left & right spigot manifolds (not shown). The extraction tailings are dispelled from each of the spigots and left and right elbows in a tailings sheet to a pour height of approximately 6 feet or 2 metres to form a first lift 178 of tailings. Once the first lift 178 is complete, the tailings distributor 100 can be moved onto first lift 178 and tailings 160 are poured again in a tailings sheet to a pour height of approximately 6 feet or 2 metres to form a second lift 178. Once again, the tailings distributor 100 can be moved onto second lift 178 and tailings 160 are poured again in a tailings sheet to a pour height of approximately 6 feet or 2 metres to form a third lift 178.

[0036] References in the specification to one embodiment, an embodiment, etc., indicate that the embodiment described may include a particular aspect, feature, structure, or characteristic, but not every embodiment necessarily includes that aspect, feature, structure, or characteristic. Moreover, such phrases may, but do not necessarily, refer to the same embodiment referred to in other portions of the specification. Further, when a particular aspect, feature, structure, or characteristic is described in connection with an embodiment, it is within the knowledge of one skilled in the art to affect or connect such module, aspect, feature, structure, or characteristic with other embodiments, whether or not explicitly described. In other words, any module, element or feature may be combined with any other element or feature in different embodiments, unless there is an obvious or inherent incompatibility, or it is specifically excluded.

[0037] It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for the use of exclusive terminology, such as solely, only, and the like, in connection with the recitation of claim elements or use of a negative limitation. The terms preferably, preferred, prefer, optionally, may, and similar terms are used to indicate that an item, condition or step being referred to is an optional (not required) feature of the invention.

[0038] The singular forms a, an, and the include the plural reference unless the context clearly dictates otherwise. The term and/or means any one of the items, any combination of the items, or all of the items with which this term is associated. The phrase one or more is readily understood by one of skill in the art, particularly when read in context of its usage.

[0039] The term about can refer to a variation of 5%, 10%, 20%, or 25% of the value specified. For example, about 50 percent can in some embodiments carry a variation from 45 to 55 percent. For integer ranges, the term about can include one or two integers greater than and/or less than a recited integer at each end of the range. Unless indicated otherwise herein, the term about is intended to include values and ranges proximate to the recited range that are equivalent in terms of the functionality of the composition, or the embodiment.

[0040] As will be understood by one skilled in the art, for any and all purposes, particularly in terms of providing a written description, all ranges recited herein also encompass any and all possible sub-ranges and combinations of sub-ranges thereof, as well as the individual values making up the range, particularly integer values. A recited range includes each specific value, integer, decimal, or identity within the range. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, or tenths. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc.

[0041] As will also be understood by one skilled in the art, all language such as up to, at least, greater than, less than, more than, or more, and the like, include the number recited and such terms refer to ranges that can be subsequently broken down into sub-ranges as discussed above. In the same manner, all ratios recited herein also include all sub-ratios falling within the broader ratio.