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EP-4126373-B1 - HYDRAULIC SHELL-SEED SEPARATOR

EP4126373B1EP 4126373 B1EP4126373 B1EP 4126373B1EP-4126373-B1

Inventors

  • MARTINSON, Wade Steven

Dates

Publication Date
20260506
Application Date
20210324

Claims (15)

  1. A method of separating a shell from a seed, the method comprising: introducing a feed stream (22) containing shells of a fruit intermixed with seeds of the fruit into a separation column (10), wherein introducing the feed stream into the separation column (10) comprises introducing the feed stream into the separation column at a feed stream location; introducing a first volume of a separation liquid into the separation column at a first liquid addition location located below the feed stream location; characterized by introducing a second volume of the separation liquid into the separation column (10) at a second liquid addition location located above feed stream location; flowing the separation liquid upwardly in the separation column (10) at a rate effective to cause the seeds of the fruit to flow upwardly with the separation liquid toward a seed outlet (14) of the separation column while the shells of the fruit flow downwardly against the upwardly flowing separation liquid toward a shell outlet (24) of the separation column.
  2. The method of claim 1, wherein the separation liquid comprises water.
  3. The method of either of claims 1 or 2, wherein the fruit is at least one of a drupe and a nut.
  4. The method of any one of the foregoing claims, wherein the fruit is a plum.
  5. The method of any one of the foregoing claims, wherein the shells of the fruit have a shell density, and the seeds of the fruit have a seed density, and a ratio of the seed density divided by the shell density is at least 0.7, preferably within a range from 0.8 to 0.95.
  6. The method of any one of the foregoing claims, wherein the separation column comprises a feed inlet intersecting a main separation column at the feed stream location, and the second liquid addition location is located on the main separation column above the feed stream location or on the feed inlet above the feed stream location.
  7. The method of claim 6, wherein the feed inlet has a diameter, and the second liquid addition location is located within a distance of the feed stream location less than or equal to the diameter of the feed inlet.
  8. The method of either of claims 6 or 7, wherein: the feed inlet extends vertically above the main separation column, and the seed outlet extends off the main separation column above the feed stream location and below the feed inlet.
  9. The method of any one of claims 6-8, wherein the separation column comprises a valve positioned below the first liquid addition location, the valve regulating a flow of shells from the main separation column to the shell outlet.
  10. The method of any one of the foregoing claims, wherein the separation column further comprises a shell discharge pipe extending vertically upwardly from the shell outlet of the separation column to a height substantially co-linear with the seed outlet.
  11. The method of claim 9, further comprising introducing a third volume of the separation liquid into the shell discharge pipe at a third liquid addition location located below the valve.
  12. The method of any one of the foregoing claims, wherein a ratio of the first volume of the separation liquid divided by a combined volume of the first volume of the separation liquid and the second volume of the separation fluid is great than 0.7.
  13. The method of any one of the foregoing claims, wherein that rate ranges from 0.03 meters per second to 0.5 meters per second.
  14. A separation system (8) for separating a shell from a seed, the separation system comprising: a separation column (10) comprising: a main separation column (12) having a seed outlet (14) and shell outlet (24); a feed inlet (16) intersecting the main separation column (12) at a feed stream location, the feed inlet (16) being configured to receive a feed stream (22) containing shells of a fruit intermixed with seeds of the fruit; a first liquid addition inlet (18) positioned on the main separation column (12) below the feed stream location, the first liquid addition inlet (18) being configured to receive a first volume of a separation liquid; and a second liquid addition inlet (20) positioned above the feed stream location, the second liquid addition inlet (20) being configured to receive a second volume of a separation liquid; at least one pump (30) configured to pump the first volume of the separation liquid to the first liquid addition inlet (18) and the second volume of the separation liquid to the second liquid additional inlet (20), thereby causing the separation liquid to flow upwardly in the main separation column (12) at a rate effective to cause the seeds of the fruit to flow upwardly with the separation liquid toward the seed outlet (14) while the shells of the fruit flow downwardly against the upwardly flowing separation liquid toward the shell outlet (24).
  15. The separation system of claim 14, wherein the second liquid addition inlet is located on the main separation column above the feed stream location or on the feed inlet above the feed stream location.

Description

TECHNICAL FIELD This disclosure relates to separators and, more particularly, to separators useful for separating fruit seeds from surrounding shell material. BACKGROUND Pneumatic separation is the process of using air to separate lighter material from heavier material in a feed stream. Pneumatic separation is based on the difference in aerodynamic properties of various constituents of the feed stream being separated. The aerodynamic property of a particle can depend upon its shape, size, density, surface area and orientation with respect to air current. In typical pneumatic separators, particles with lower terminal velocities are lifted by the air current while particles with higher terminal velocities than the air velocity fall down through the air current. The air velocity can be adjusted to change the separation characteristics of the feed stream being processed. While comparatively simple and widely used, pneumatic separators are not suitable for all applications. For example, pneumatic separators may not provide complete or efficient separation between materials having similar aerodynamic properties. Rather, for such feed streams, the materials desirability separated from each other may exhibit similar terminal velocities against the upward flowing current of air, resulting in inefficient and/or ineffective separation. An example of a hydraulic separator is known from US2464005A. SUMMARY In general, this disclosure is directed to devices and techniques for separating different components in a feed stream from each other using a hydraulic fluid medium. While the described devices and techniques can be used to separate any desired two solid materials from each other, in some implementations, the devices and techniques are utilized to separate two materials having substantially similar densities from each other. A feed stream containing the two or more materials to be separated from each other can be introduced into a separation column having one or more liquid addition inlets, including at least one liquid addition inlet positioned below the feed stream entry location. A liquid separation medium, such as water, can be introduced into the separation column via the one or more liquid addition inlets. As the liquid flows upwardly in the separation column, a comparatively faster-settling material may flow downward against the liquid flow while a comparatively slower-settling material may flow upwardly with the liquid flow. The increased density of the hydraulic separation liquid as compared to a pneumatic separation fluid can provide more efficient and effective separation between the two components of similar density. While the separation column can have a variety of different configurations and features, in some examples, the separation column includes at least two liquid addition inlets: one liquid addition inlet positioned below a feed inlet where a feed stream of the material to be processed is introduced and one liquid addition inlet positioned above the feed inlet. Configuring the separation column with multiple liquid addition inlets can be useful to drive efficient hydraulic separation of a comparatively dense material from a material having a lesser density in the column. With some feed streams, the feed stream may not be composed of equal amounts of faster and slower settling material (heavier and lighter materials, respectively), but instead may have a disproportionate ratio of the two materials. For instance, the feed stream may have a greater amount of the faster-settling material than the slower-settling material. As the feed stream separates in the hydraulic separation column into an upward flowing stream of the lighter material and a downward flowing stream of the heavier material, the velocity of the upward flowing stream may diminish due to the disproportionate bulk of the material flowing downward. To maintain the upward velocity of the liquid (and lighter material carried therewith), additional liquid may be introduced into the second liquid addition inlet positioned above the feed inlet, providing an additional flow of liquid for efficient separation. Additionally or alternatively, the second liquid addition inlet may not be supplied with a continuous flow of liquid but may be only periodically supplied with liquid, e.g., to break or relieve plugging or other flow restrictions within the separation column. One example application where a hydraulic separation column and/or related separation technique may be beneficially used is to separate fruit shells from fruit seeds. For example, the hydraulic separation column and/or related separation technique may be used to separate the shell of a stone fruit from the seed of the stone fruit that is contained inside the shell. The seed and shell of the stone fruit may have similar densities, making recovery of the seed from the contaminating shell material challenging. Once separated, the seed may be used for a variety of downstream applications