Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
MATERIAL SEPARATION BY DENSITY THROUGH FLUID DYNAMICS
Document Type and Number:
WIPO Patent Application WO/2019/087131
Kind Code:
A1
Abstract:
Disclosed is a particle separation method for separating particles from a mixture. Firstly, the particles are classified by size in lots of similar or equal size to facilitate its separation by density. Thereafter, the particles are allowed to free fall in a container filled with a fluid. The falling particles are drained to separate the falling particles by its terminal velocity. And then, the falling particles are separated by applying a counter flow fluid to its fall at a velocity between the terminal velocities of the particles to be separated.

Inventors:
MARQUEZ, Federico (5108 Ganymede Dr, Austin, Texas, 78727, US)
Application Number:
IB2018/058597
Publication Date:
May 09, 2019
Filing Date:
November 01, 2018
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
MARQUEZ, Federico (5108 Ganymede Dr, Austin, Texas, 78727, US)
International Classes:
B03B5/62; B01D45/06; B07B4/02
Download PDF:
Claims:
WHAT IS CLAIMED IS:

1. A particle separation method, comprising:

classifying particles by size in lots of similar or equal size to facilitate its separation by density;

allowing the particles to free fall in a container filled with a fluid; draining the falling particles to separate the falling particles by its terminal velocity; and

separating the falling particles by applying a counter flow fluid to its fall at a velocity between the terminal velocities of the particles to be separated.

2. The particle separation method of claim 1, wherein a fluid flow is facilitated through a duct or a chamber with different sizes to provide different fluid velocities through it so that the different terminal velocity of the particles suspend them at different stages of the duct or the chamber.

3. The particle separation method of claim 1, wherein a valve, door or compartment is activated in a fluid duct to guide the falling particles suspended in the counter flow fluid.

4. The particle separation method of claim 1 , further comprising an alternate fluid flow for terminal velocity separation to capture the suspended particles.

5. The particle separation method of claim 1, further comprising setting the fluid flow velocity by calculating the terminal velocity of the falling particles considering temperature effect on fluid dynamic viscosity.

6. The particle separation method of claim 5, wherein the fluid flow velocity is obtained by calculating the terminal velocity of the falling particles considering the temperature effect on a fluid density of the fluid.

Description:
MATERIAL SEPARATION BY DENSITY THROUGH FLUID DYNAMICS

CROSS-REFERENCE TO RELATED PATENT DOCUMENTS

[0001] This patent application claims the benefit of priority of U.S. Provisional Application No. 62/580,937, entitled "PARTICLE SEPARATOR BY TERMINAL VELOCITY," filed Nov. 2, 2017, and U.S. Provisional Application No. 62/740,393, entitled "TERMINAL VELOCITY PARTICLE SEPARATION PROCESS," filed Oct. 2, 2018, which are hereby incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[0002] The present invention relates generally to material separation, and, more particularly, to a method and a system for separating a plurality of particles from a mixture by density through fluid dynamics.

BACKGROUND

[0003] Obtaining of various minerals that are being used on daily basis is a complex process. Mining is extraction of valuable minerals or other geological materials from the earth, usually from an orebody, lode, vein, seam, reef, or placer deposit. These deposits form a mineralized package that is of economic interest to the miner. Mining is required to obtain any material that cannot be grown through agricultural processes, or created artificially in a laboratory or factory. Thus, mining is more than finding where the desired resources are available. In reality, resources are available in many places and some of the materials almost in all places. Its abundance is what changes from every material and the specific concentration of each material. Some of the materials are of very low concentrations like gold for which the extraction is sometimes as little as 1 PPM (Particle Per Million) i.e., one gram of gold is present in every ton of natural materials. So most of the effort is in getting that one gram apart from the rest of the materials.

[0004] Traditionally, methods like lixiviation and flotation are used to obtain the desired material and are intense in the use of chemicals. Most of these processes are chemically targeted to a specific mineral or material that is desired to be extracted. Gravitational concentration is known from long time and it allows to concentrate the desired minerals or materials by the density difference, like the Wilfred table or the cyclone, or hydro cyclone. They do use fluid dynamics to concentrate by density, but with the realization and implementation of the present invention, separation can be made with more accuracy, and by using part of its process, even antique methods can be improved. Also, the various known methods generally operate above 150 microns particle size while the methods disclosed in the present invention can operate at lower sizes.

BRIEF SUMMARY

[0005] It is an objective of the present invention to provide a method and a system for separating a plurality of particles from a mixture by density through fluid dynamics. A particle can be moved by a force through a fluid. Such force on the particle can be calculated. Further, speed of the particle may be determined using Stokes Law that defines the speed of the particle as terminal velocity. The terminal velocity is defined by the density of the fluid, the density of the particle, the size of the particle, and the viscosity of the fluid.

[0006] Upon classification of particles into similar or same size lots, the particles are put into the fluid. Putting the particles (of the same or similar size) into movement by the force into the fluid, the particles of different density will have different velocity (i.e., the terminal velocity). When this process is performed without the previous classification, then the particles of bigger size and lower density can have a similar velocity than the particles of smaller size and higher density, making not so efficient process.

[0007] By performing the previous classification of the material by the particle size, the density concentration efficiency is increased. Thus, with the particles of higher density and similar size, the particles exhibit an efficient gravitational process for separating by the density, and by the complete process of the present invention, both the accuracy and the efficiency can be improved, making concentrations of particles by their densities.

[0008] By managing the fluid dynamics of the suspended particles in fluids and calculating the speed of each of the particles through their travel in the fluid, the particles can be classified and separated into desired densities. Minerals have different densities, and they can go through many metals. Rare earth minerals have high densities. Also, lead and gold between many others with different density, many being different than the average ore density, that most time ranges from 2.6 g/cm3 to 3 g/cm3. This allows to make concentrations and separations. By making the concentrations, the amount of chemicals can be reduced even if a chemical process is made. It is made on a basis of a lower amount of material from the ore, which is ideal for the separation of specific chemical material and not just the density separation which can concentrate different materials of similar density.

[0009] There are many ways to establish a process in which the particles are moving through the fluid that can create a condition where the density has an effect in the velocity of each particle. Such process is used to separate each particle by its density. The moving force can be a gravitational force, or an induced force like centrifugal. The movement of the particle through the fluid can be the result of the movement of the particle itself, the movement of the fluid, or both. Further, the process can be continuous or in batch, removing the particles suspended or contained in the fluid, sedimentation of the particles or many other. Here are some samples of the process to separate the different materials or particles and many more will come as the principle promotes innovation to new models of material classification.

[0010] In an embodiment, the present invention relates to the separation of particles in a material by their terminal velocity. A particle of a given size and density has a terminal velocity when moving through a fluid. The velocity of the particle or the terminal velocity is defined by the particle size, the particle density, the fluid density, the fluid viscosity, and the particle force. By standardizing the particles by size, similar or equal, and being the different particles moving by the same fluid, which holds the same viscosity and density, the velocity of the particles will differentiate by the density of the particle. This is used to separate the particles by density, in different ways.

[0011] These and other features and advantages of the present invention will become apparent from the detailed description below, in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0012] The novel features which are believed to be characteristic of the present invention, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which a presently preferred embodiment of the invention will now be illustrated by way of example. It is expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention. Embodiments of this invention will now be described by way of example in association with the accompanying drawings in which:

[0013] FIG. 1 is a schematic representation for illustrating terminal velocity of two particles with the same or similar size and different densities, in accordance with an embodiment of the present invention;

[0014] FIG. 2 is a schematic representation for illustrating separation of the two particles based on their movement in a fluid, in accordance with an embodiment of the present invention;

[0015] FIG. 3 is a schematic representation for illustrating a process for reusing or recycling the fluid, in accordance with an embodiment of the present invention;

[0016] FIG. 4 is a schematic representation for illustrating an intermittent fluid vessel operation, in accordance with an embodiment of the present invention;

[0017] FIG. 5 is a schematic representation for illustrating an improvement that makes possible better results in particle separation, in accordance with an embodiment of the present invention;

[0018] FIG. 6 is a schematic representation for illustrating a variation of separating particles of the same or similar size and different densities at the same time, in accordance with an embodiment of the present invention;

[0019] FIG. 7 is a schematic representation for illustrating a mechanism to separate and classify the particles, in accordance with an embodiment of the present invention; and

[0020] FIG. 8 is a schematic representation for illustrating a process of separating particles into lots of the same or similar sizes prior to making the process of separation of the particles, in accordance with an embodiment of the present invention. [0021] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description of exemplary embodiments is intended for illustration purposes only and is, therefore, not intended to necessarily limit the scope of the invention.

DETAILED DESCRIPTION

[0022] As used in the specification and claims, the singular forms "a", "an" and "the" may also include plural references. For example, the term "an article" may include a plurality of articles. Those with ordinary skill in the art will appreciate that the elements in the Figures are illustrated for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some of the elements in the Figures may be exaggerated, relative to other elements, in order to improve the understanding of the present invention. There may be additional components described in the foregoing application that are not depicted on one of the described drawings. In the event such a component is described, but not depicted in a drawing, the absence of such a drawing should not be considered as an omission of such design from the specification.

[0023] Before describing the present invention in detail, it should be observed that the present invention utilizes a combination of components or set-ups, which constitutes a method and a system for separating a plurality of particles from a mixture by density through fluid dynamics. Accordingly, the components have been represented, showing only specific details that are pertinent for an understanding of the present invention so as not to obscure the disclosure with details that will be readily apparent to those with ordinary skill in the art having the benefit of the description herein. As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting but rather to provide an understandable description of the invention. [0024] References to "one embodiment", "an embodiment", "another embodiment", "yet another embodiment", "one example", "an example", "another example", "yet another example", and so on, indicate that the embodiment(s) or example(s) so described may include a particular feature, structure, characteristic, property, element, or limitation, but that not every embodiment or example necessarily includes that particular feature, structure, characteristic, property, element or limitation. Furthermore, repeated use of the phrase "in an embodiment" does not necessarily refer to the same embodiment.

[0025] The words "comprising," "having," "containing," and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items or meant to be limited to only the listed item or items.

[0026] Techniques consistent with the present invention provide, among other features, a method and a system for separating a plurality of particles (having different densities but the same or similar sizes) from each other by terminal velocity or gravitational process. Unless stated otherwise, terms such as "first" and "second" are used to arbitrarily distinguish between the elements such terms describe. Thus, these terms are not necessarily intended to indicate temporal or other prioritization of such elements. While various exemplary embodiments of the disclosed system and method have been described above it should be understood that they have been presented for purposes of example only, not limitations. It is not exhaustive and does not limit the invention to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practicing of the invention, without departing from the breadth or scope.

[0027] The process of separation of particles by terminal velocity or gravitational process will now be described with reference to the accompanying drawings which should be regarded as merely illustrative without restricting the scope and ambit of the present invention.

[0028] FIG. 1 is a schematic representation 100 for illustrating terminal velocity of two particles with the same or similar size and different densities, in accordance with an embodiment of the present invention. The schematic representation 100 shows a set-up 105 (such as a vessel or container) that is filled with a fluid such as water. The container 105 includes low and high densities particles. For example, the particles 101, 102, 103, and 107 are high densities particles and the particles 104 and 106 are low densities particles. These particles are of the similar or same size.

[0029] In an embodiment, the high density particle 103 and the low density particle 104 are moving by force. In this case, the force is natural gravity i.e., the gravitational force. Further, the fluid (in which the high density particle 103 and the low density particle 104 are moving) is water in this case, but may also be air instead of water. The high density particle 103 and the low density particle 104 moving by force in the fluid will have different terminal velocity. This means that if the high density particle 103 and the low density particle 104 are released at the same moment into the fluid in a given time, the high density particle 103 and the low density particle 104 will advance different distances. For example, the low density particle 106 advances less than the high density particle 107. This distance difference makes it capable to separate both the particles. If the size difference affects the terminal velocity less than the density difference, different particles with different densities can be separated.

[0030] In an embodiment, to obtain the particles of the same or similar size (such as the particles 101, 102, 103, 104, 106, and 107), several methods can be used like mesh or other. By having the particles of the similar or same size, the particles can be separated by the density difference. A similar process can be realized for particles of the same or similar density and a size difference, being separated by their terminal velocity.

[0031] FIG. 2 is a schematic representation 200 for illustrating separation of two particles based on their movement in a fluid, in accordance with an embodiment of the present invention. After describing how the particles can have different velocity or different terminal velocity as defined by the Strokes law, here is the schematic representation 200 that shows a set-up 201 (such as a vessel or container) that is filled with the fluid such as water. Other methods can be used for gaseous fluids. The fluid density and viscosity of the fluid is important as it affects the terminal velocity. Here is an example with water.

[0032] As the particles of the same or similar size are released at the same time, a particle with a lower density (such a low density particle 202) and a particle with a higher density (such as a high density particle 203) will have a distance difference in their falling advance. Here, the fluid being a liquid, it is easy to separate the particles. By having an outlet 207 at a higher altitude of the container 201, the low density particle 204 that is slower can be drained with the containing liquid by opening a higher valve 210 that moves the slurry or liquid into the higher outlet 207. For example, when the higher valve 210 is opened, the slurry or liquid containing the slower particles suspended in the fluid is moved into the higher outlet 207, separating the slower particles, and thereafter collecting the slower low densities particles (such as the particles 208).

[0033] Once the slower low densities particles are out of the container 201, the remaining particles in the container 201 are the particles with faster velocity (such as the particles 205). These faster high densities particles can be now drained by a lower valve 211 that leads to a lower outlet 206. This will separate the faster high densities particles such as the particles 209. Being terminal velocity of the particles given by size and density, being the particles of the same or similar size, density will make the advance difference.

[0034] In an embodiment, several situations can be made to separate the low and high densities particles. This method can have several compartments or valves at different height. It is also possible to separate different particles of different terminal velocity in a single particles fall. The result of such fall will be the separated particles of lower terminal velocity (such as the particles 208) from other particles of higher terminal velocity (such as the particles 209) from a mixed particles source. For example, if they have the same or similar size, then it can result on particles separation by density. This is very useful because minerals have density difference, and by this means, the minerals can be separated or concentrated without the use of intense chemicals for lixiviation or flotation, or can be first concentrated and minerals that have just a few parts per million concentrations can be concentrated more before the chemicals process. The process can be computer calculated. Density of the fluid can be obtained by measuring it manually or automatically by one or more sensors. Viscosity can also be measured automatically by one or more sensors or manually, and by this, the velocity of the desired characteristics of the desired particles can be calculated defining the time for valves in the process or the process definition. The same equipment can work for many uses and configurations.

[0035] FIG. 3 is a schematic representation 300 for illustrating a process for reusing or recycling the fluid, in accordance with an embodiment of the present invention. In an embodiment, the schematic representation 300 shows a set-up 301 (e.g., a fluid container or vessel) that can be used for reusing or recycling the fluid such as water. The fluid is used to have the proper terminal velocity for the particles (such as the particles 302 and 304), which in turns enables the particles to separate from each other. Let's say that for these particles, given their size and densities, it is hard to make it in air. Also, the fluid provides a sedimentation process that helps to separate the particles from each other, and the terminal velocity attained by these particles is helpful during such process.

[0036] Upon separation, the particles 302 and 304 have been represented as 303 and 305, respectively. After being separated, the particles 303 and 305 drains through their respective valves. For example, the particle 303 drains through an upper valve and the particle 305 drains through a lower valve. After being drained through the upper valve, the particle 307 will sediment at the bottom of a channel 311 and the fluid in this channel 311 is pumped back by means of a pump system 309 for reuse.

[0037] During the pumping process, the fluid is pumped through a channel 310 and is directly pumped into the container 301. In an alternate embodiment, the fluid is pumped through the channel 310 into an intermediate tank 308 that is preferably at an altitude higher. Thereafter, the fluid flows from the intermediate tank 308 into the container 301 so that it can be easily refilled in a faster way. The transfer of reusable fluid into the container 301 by having the intermediate tank 308 allows to pump (by the pump system 309) the fluid more constantly even when the cycles require intermittent filling of the container 301. This process of closed loop can also be performed for air or in closed vessels for other gases using fluid flows.

[0038] FIG. 4 is a schematic representation 400 for illustrating an intermittent fluid vessel operation, in accordance with an embodiment of the present invention. The schematic representation 400 shows a set-up that is used for the representation of the intermittent fluid vessel operation. Combined particles 406 are loaded into the machine. The combined particles 406 are allowed to fall freely into the fluid 403 by gravity (i.e., under the gravitation force). When the particles are advancing through the fluid 403, the particles (such as the particles 404 and 405) are separated by distance. Thereafter, the particles are separated in the fluid by separate fluid outputs 401 and 402. When the particles of slower terminal velocity (such as the particles 404 or 408) are evacuated, the vessel lowers the fluid level and is ready to evacuate the remaining particles of higher terminal velocity (such as the particles 405 or 407). This can be done in many levels for many classes of particles to be separated. It can be done intermittent by a control compartment 409 so that there is time for the particles to separate and the slower particles 404 are not mixed with the faster particles 405 that entered the fluid after, so it an intermittent process. The process can be alternating the fluid vessels to allow time to the particles to advance at different velocity.

[0039] FIG. 5 is a schematic representation 500 for illustrating an improvement that makes possible better results in particle separation, in accordance with an embodiment of the present invention. The schematic representation 500 shows a set-up 506 that has been used to show the simple improvement that makes possible better results in the particle separation process. The traditional classification of particles by size 501 is performed prior to the separation process of the particles by density 502. The separation process can be described by fluids in water, or other like cyclone, or sedimentation at different distance due to the faster falling of higher density particles and produces a better result for the particle separation. As a result, lots of different bigger particle sizes 503 and 504 from smaller particle sizes 505 might result in a bigger number of lots as the lots of bigger particle sizes 503 and 504 will separate in the higher density from the lots of lower density and the lots of smaller particle sizes 505 will also separate in the higher density from lower density particles 505, which can be useful separated or can be mixed by groups of density.

[0040] The flow of a fluid that can be water, air or other is injected in the lower part of a duct 501 or 502 with particles suspended in it as slurry or dust 504 and 505 that is falling by gravity in counter flow of the fluid. The particles 504 and 505 have different densities. In this case, they have the same size of particles but different densities. The particles 503 and 504 of higher densities are capable of falling down at the speed of the fluid which is lower than the terminal velocity of the particle 503. The lower density particle 505 of the same or similar size will fall slower having a slower terminal velocity and will remain suspended or even elevate by the fluid force. This difference of terminal velocity between the particles 503 and 504 of higher densities to the particle 505 of lower density makes it capable to separate them. For example, the high density particle 504 has a terminal velocity of 2 m/s and the lower density particle 505 has a terminal velocity of 1 m/s by injecting the fluid through the ducts 501 and 502 at a rate that results in a fluid velocity of 1.5 m/s in the tunnel 506. The higher density particle will fall to the bottom of the recipient with the other particles 503 that have a terminal velocity higher than the fluid velocity. In this case, the lower density particle 505 will remain suspended or be evacuated from the separator. The separation is made by calculating the terminal velocity of the desired particle size and density difference to be separated. Similar densities can separate different sizes and similar sizes can separate different densities. There is many possibilities by calculating the fluid dynamics that can be estimated by stokes law formula or other. The ideal fluid can be decided with the dynamic viscosity and density useful for the particle size and density to separate. Different variations can be made with this principle.

[0041] FIG. 6 is a schematic representation 600 for illustrating a variation of separating particles of the same or similar size and different densities at the same time, in accordance with an embodiment of the present invention. The schematic representation 600 has been illustrated to show a variation of the basic model in which that particles are being separated by similar size. This has the objective to demonstrate the capability to separate particles 603, 604, 605, 607, and 608 of different densities at the same time. The energy involved to separate is the fluid flow so that it can be more efficient and effective to separate several densities or sizes of particles with the same flow. For example, the particles 603, 604, 605, 607, and 608 of the same or similar size with different densities. In this case, the particles 607 and 608 of one material are with low densities, other particles 605 of a material are with medium density, and other particles 603 and 604 are with high densities. The fluid flow into the ducts 601 and 602 will have different velocity due to the variation of the volume of the ducts 601 and 602 and the constant mass and volume of the fluid that will fill the container resulting in different velocities. For example, a high speed may be attained where the duct is narrow 606 and the speed decreases where the duct increases in its size 609 and further slows down where the duct has a bigger volume 610 to fill. This different speeds of fluid make it possible to separate different particles with different terminal velocities. The process to stock them separated will be shown later, but draining at several parts can be made continuous or in batch.

[0042] FIG. 7 is a schematic representation 700 for illustrating a mechanism to separate and classify the particles, in accordance with an embodiment of the present invention. The schematic representation 700 has been shown to express the mechanism to separate the particles and classify them. It is shown before how particles separate, given their difference in densities and sizes, particles do fall into the bottom 701 or do suspend in the fluid 706. The particle at the bottom can be evacuated and are already separated, if the suspended particles are ejected by the fluid. They can be collected where ejected. If that is not possible and if several fluid velocities are used in the duct 702, there will be particles at different stages of the duct 702. By this simple method, they can be classified and stock separated by their terminal velocity. A compartment door 704 can block the free fall of the particle into the bottom and transfer it to the desired classification 703. The exit for the particles will allow it out of the fluid duct 702. The blocking door 704 for preventing particles from falling to the bottom can be the same or a different one than the opening door 705 that exits the particles out of the duct 702. This same door use is exemplified 707 to explain the use case for several doors that can be used to classify several terminal velocity particles using different duct sizes and fluid speeds. The fluid velocity can be intermittent in this method, that will later be shown on how to make it efficiently.

[0043] FIG. 8 is a schematic representation 800 for illustrating a process of separating particles into lots of the same or similar sizes prior to making the process of separation of the particles, in accordance with an embodiment of the present invention. The process of separating the particles 801 into lots 802 and 803 of the same or similar sizes (prior to making the process of separation of the particles by terminal velocity or gravitational process 804) makes the process more efficient in avoiding bigger particles of lower density 806 mix in the process with smaller particles of lower density 808. This makes it possible to separate the lots of higher density 805 of the same size of particles from particles of the same size having lower density 806. Also, the same is performed with the lots of different size 807 and 808, having also separated by the higher density of the particles 808 from the lower density of particles 807 of that size. Such lots will result into the particles that are separated by size and density and that can be mixed back together by similar density or used in the different sizes and densities.

[0044] Although the present invention has been described with respect to various schematic representations 100-800, it should be understood that the proposed particle separation methods and systems can be realized and implemented with varying shapes and sizes of particles with varying densities, and thus the present invention here should not be considered limited to the exemplary embodiments and processes described herein. The various dimensions may be modified to fit in specific application areas. [0045] Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention.