Apparatus and method for liquid separation of materials

An apparatus and method are provided for the liquid separation of materials, and particularly for the separation of edible portions of a material from unedible portions, by utilizing the specific gravity differential between such materials. The materials are thrust into a receptacle which contains a solution of a predetermined density, and are separated into their constituents by subjecting same to an issuing stream of solution produced by jet manifolds. This issuing stream operates with the solution to cause separation of the lighter constituents which float to the upper portion of the receptacle from the heavier constituents which tend to sink in the solution. At least two conveyor belts are provided each being within the solution; the first of which is disposed within the receptacle to receive the lighter constituents and a second disposed below the first to receive the heavier constituents. Both conveyors discharge the respective constituent materials.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to devices and methods for the liquid 
separation of materials based upon differences in specific gravity. 
Particularly, the invention relates to an apparatus and method for the 
liquid separation of edible products from unedible portions thereof. Even 
more specifically, it relates to a liquid separation system for the 
treatment of raisins, wherein the edible fruit or raisin, is separated 
from the unedible portion which includes: stems, cap stems, waterberries, 
mold, and other waste. 
2. Prior Art Statement 
In the production of raisins, grapes are harvested from the vineyards in 
bunches and then dried to a moisture content of about 20%. These bunches 
of dried grapes include waste materials, such as, for example, the dried 
vines, stems, mold, and the like. The product is then transported to 
storage areas where it is fumigated and dried until the fruit has a 
moisture content of approximately 14%. The storage areas are generally 
fabricated of wood, and therefore, the waste materials further include 
wood particles which become matted into the fruit. The grapes are then 
processed in a series of mechanical operations designed to separate the 
fruit from a majority of the waste materials utilizing tumblers, rollers, 
water baths, etc. The product is then passed through a fluming station and 
thereafter, ready to be finally treated to produce a product suitable for 
commercialization. 
In processing the edible and unedible materials, as above, it has been 
customary to employ laborers to remove such waste materials from the 
finally processed raisin. A number of hand sorters remove the unedible 
materials as the fruit and waste materials are transported as for example, 
by shaker screens, conveyors, and the like. Hand sorting, today, has 
become unfeasible due to prohibitive labor expenses and more exacting 
standards, including more stringent specifications as to the content of 
fruit sold to consumers (where only several parts per thousand waste in 
the commercial product is permitted). Moreover, the present production 
techniques which utilize high velocity air currents followed by water 
baths do not produce commercially acceptable raisins. It has therefore 
become increasingly important to develop improved mechanical devices to 
perform the above type separation in a more efficient and economical 
manner. 
While some of the prior art is directed to the general principle of 
separating edible portions of fruit from unedible portions and other waste 
materials, it is in large part directed to separation by means of 
mechanical abrasion between concentric tubular members, interacting fruit 
between tubular members or rolls, or utilizing fan blades and the like to 
impel the raisins into a wall, against other raisins, or into baffles, 
screens, and the like. 
The general principle of floation separation of frost damaged citrus fruit 
from undamaged citrus fruit is known. See for example: U.S. Pat. No. 
994,654--issued to Parker and U.S. Pat. No. 2,283,512--issued to Sias. 
U.S. Pat. No. 2,152,143, issued to Martin, is directed to sluicing raisins 
through a riffled structure of a hydraulic separator where stones and 
heavier particles (including raisins) drop out and fragments, such as cap 
stems, float toward the top of a water bath. 
U.S. Pat. No. 1,269,966, issued to Shepard is directed to the treatment of 
raisins by immersing same in a body of water which is agitated by a worm 
gear, the latter of which mechanically interacts with the raisins to 
dislodge the cap stems. The raisins and heavier foreign materials are 
conveyed by the worm gear through a section of the tank where the heavier 
materials are pumped out and into a second stage of the apparatus for 
further treatment utilizing an agitating screen and pressurized fluid 
sprays. This process ultimately relies upon a screening process for the 
final separation of the fruit from the waste materials. 
In U.S. Pat. No. 1,754,923, issued to Weigand, a liquid separation 
technique is utilized to separate prunes into various qualities and grades 
by progressively subjecting them to more dense solutions. 
The prior art does not provide a suitable apparatus and method for the 
liquid separation of materials which is highly efficient and economical 
and which is compatible with present processing techniques and may be 
incorporated "in-line" to treat commercial quantities of materials. 
Moreover, the known prior art techniques have been proven to be 
unacceptable in the separation of raisins from stems, cap stems, 
waterberries, mold, wood chips, and other waste. 
Accordingly, an apparatus and method is needed to meet todays standards in 
providing commercial quantities, of product free of mold, substandards, 
and other unedible waste materials. The present invention fills such a 
need by providing a means to treat and process free flowing raisins at 
acceptable standards and at feed rates incurred in production type 
"in-line" processes. Bulk materials are thrust into a solution of 
predetermined density and then reacted with an issuing stream of solution 
which combines to separate the materials. Conveyors are provided to 
transport the respective constituents, above, from the receptacle for 
disposal or further treatment. The present invention comtemplates the 
separation of various materials utilizing specific gravity differentials, 
and is specifically directed to the separation of edible materials from 
unedible materials including waste. While the invention is specifically 
described with reference to the processing of raisins, it is to be 
understood that the apparatus and principles relative thereto can equally 
be applied to promote separation of various types of materials including, 
for example, the separation of poultry from bones and gristle, green beans 
from stems and leaves, peas from pods and stems, and the like. 
SUMMARY OF THE INVENTION 
The concept of the present invention resides in the utilization of a device 
to provide a sufficient quantity of free flowing materials which may 
include raisins, waterberries, stems, cap stems, mold, wood chips, and 
other waste materials, at a uniform rate and in a uniform manner into a 
container of solution having a predetermined density. The materials are 
thrust into the solution with sufficient velocity to disperse the 
materials, breaking them apart, and dispersing same within the solution 
where spray manifolds impart an issuing stream of the solution within the 
container and underneath the level of solution which impinges upon the 
materials, and in fact, may be adjusted to facilitate the separation of 
the materials into constituent parts. 
This concept is effected by an apparatus which includes feed means disposed 
at a predetermined height above the solution and over the receiving 
portion of the receptacle. The feed means function to discharge the 
materials into the receptacle at a uniform rate and in a uniform manner. 
The receptacle comprises a container having a receiving portion and a 
discharge portion and contains a homogeneous solution of predetermined 
density which in most instances is a saccharide solution. The receptacle 
is provided with manifold means in operative engagement with the receiving 
portion of the receptacle and located beneath the solution level for 
issuing a stream of solution toward the discharge portion of the 
receptacle at a rate of flow which is substantially uniform throughout the 
width of the receptacle. The manifold means additionally includes 
adjustment means operably engaging the manifold for varying the direction 
of the issuing stream of solution, flow rate means operably engaging the 
manifold for varying the uniform flow rate of the issuing stream of 
solution, and suction means in fluid engagement with the receptacle and 
the manifold means for removing the solution from the receptacle and 
distributing same to the manifold at a predetermined rate. First conveyor 
means is provided and disposed in the discharge portion of the receptacle, 
the receiving portion of which is submerged in the solution at a point 
just below the solution level such that the waterberries, mold, stems, cap 
stems, and other waste materials, lighter than the raisins, are removed. 
For purposes of more actively controlling the types of materials 
selectively removed from the solution, adjustable plow means is provided. 
The adjustable plow means is operatively engaged with the receiving 
portion of the first conveyor means and is utilized to remove materials 
which would otherwise flow below the first conveyor means. Additionally, a 
second conveyor means disposed below the first conveyor means and located 
in the discharge portion of the receptacle, is provided, for removal of 
the fruit or raisins. The apparatus as thus described, and especially, the 
issuing stream adjustment means, the flow rate means, and the plow means, 
are separately adjustable or may be adjusted in any combination while 
"in-line" to improve separation of and between the raisins and the waste 
materials. 
The present invention provides a method for the separation of the above 
materials by thrusting the materials into a solution having a specific 
gravity greater than that of the waste materials, simultaneously 
subjecting the materials to an issuing stream maintained at a flow rate 
which is substantially uniform throughout the receptacle and removing the 
materials by first and second conveyor means, whereupon the waste 
materials may be disposed or stored and the raisins be conveyed "in-line" 
for further processing. The process results in the processing of 
commercial quantities of clean raisins due to the highly efficient removal 
of waste materials. It has been found that a solution recovery system may 
be added to the apparatus to more economically operate the present 
invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The Apparatus 
Referring to FIGS. 1 and 6, reference numeral 10 refers generally to the 
apparatus of the present invention which is utilized to carry out the 
method of the present invention. 
More specifically, apparatus 10 is supported by frame 11 which is 
fabricated of structural steel and used to support apparatus 10 in a 
stable manner. Apparatus 10 includes receptacle 100, recirculating system 
200, and conveyor system 300. It may optionally include solution recovery 
system 500. In the preferred embodiment, the portions which contact edible 
materials, or recirculate solution are preferably fabricated of stainless 
steel. 
Receptacle 100 is a container for holding solution 20 and comprises, rails 
101 which are integral with two side members 102, receiving floor 105 and 
discharge floor 107. Receptacle 100 is further divided into a receiving 
portion 140 and a discharge portion 150, as described more fully 
hereinbelow. Beginning with receiving portion 140, receptacle 100 forms a 
container comprising receiving floor 105 integral with side members 102 
the former of which slopes generally downwardly from rails 101 and is 
integral with floor 106. Floor 106 is integral with discharge floor 107, 
which slopes increasingly upwardly from floor 106 and is integral with 
rails 101. Receptacle 100 as thus far described forms a container for 
holding solution 20 which is more fully described hereinbelow. 
Discharge portion 150 of receptacle 100 contains conveyor system 300 which 
comprises a first conveyor belt 310 and second conveyor belt 360. First 
conveyor belt 310 contains a receiving portion 311 and discharge portion 
312 which constitutes the remaining portion of first conveyor belt 310. 
Referring to FIG. 4, receiving portion 311 is shown slightly submerged 
beneath solution level 21 and it is inclined upwardly therefrom for 
carrying materials received by receiving portion 311 upwardly for removal 
out of solution 20. Second conveyor belt 360 is located beneath first 
conveyor 312 and also comprises a receiving portion 361 and a discharge 
portion 362, the latter of which is defined by that portion of conveyor 
360 which extends from and without solution level 21. Second conveyor 360 
functions to receive and collect materials not collected by first conveyor 
belt 310 and to convey same from receptacle 100. Second conveyor belt 360 
is inclined upwardly in the manner of first conveyor belt 310 and is 
substantially parallel to discharge floor 107 of container 100. Conveyor 
belts 300 are housed in conveyor frame 160 and supported therein by shafts 
304. Conveyor frame 160 is pivotally mounted to frame 11 by pivotal shaft 
450. 
More specifically, first conveyor belt 310 and second conveyor belt 360 are 
constructed of fryer chain with approximately 1/8" open mesh. This wire 
mesh belt functions to support the materials being conveyed from 
receptacle 100 while providing means to permit solution 20 to pass 
therethrough and back into receptacle 100. It is to be realized that the 
selection of type chain is dependent upon its ultimate use and 
particularly, the type and quantity of the materials to be conveyed from 
receptacle 100, and therefore, the size of open mesh, and the type of 
construction material will vary, as is known in the art. In the preferred 
embodiment, a wire cloth belt is utilized, and is supported by roller 
chain 301 which is in turn supported by key stocks (not shown) and 
sprockets 303' and 303", which are supported by shafts generally 
designated by numeral 304. Motor 305 drives shaft 305A which drives gear 
306. Gear 306 is connected to gear 307' by chain 308'; gear 307' is 
integral with shaft 304C' which is integral with sprockets 303' which in 
turn drive first conveyor belt 310. Gear 307" is also integral with shaft 
304C' and lies between gear 307' and sprockets 303'. Gear 307" is 
connected to gear 309 by chain 308"; gear 309 is integral with shaft 304C" 
which is integral with sprockets 303" which in turn drive second conveyor 
belt 360. 
As is best illustrated in FIGS. 1 and 3, first conveyor belt 310 is 
supported by shafts 304A', 304B' and 304C' and second conveyor belt 360 is 
supported by shafts 304A", 304B" and 304C". It is to be noted that in one 
embodiment of apparatus 10 conveyor belts 310 and 360 incline upwardly 
from shaft 304A to shaft 304B and terminate at 304B where motor 305 will 
be mounted through a chain and gear mechanism, as described above (not 
shown), to drive conveyors 300. As thus far described, the first and 
second conveyor belts 310 and 360 will be complete and operable, and 
apparatus 10 may be placed in line for the production of raisins. In the 
preferred embodiment, however, first and second conveyor belts 310 and 360 
are hipped and extend substantially horizontally from shafts 304B to 304C. 
Hipped portions 315 and 365 are substantially parallel to floor 106 and 
wire mesh conveyors are further supported by shafts 304B-2 and 304-B"-2. 
It has been found that hipped portions 315 and 365 respectively provide 
more time for the solution 20 to pass through conveyor belts 300. 
Pan 320 is provided just beneath first conveyor belt 310 and secured to 
conveyor frame 160, to collect drippings of solution 20 from first 
conveyor belt 310 and to transmit same to receptacle 100. Referring now to 
FIG. 4, pan 320 is extended from a point just above solution level 21 to 
shaft 304B', in parallel relation with first conveyor belt 310. 
Thereafter, it extends in parallel relation to and beneath hipped portion 
315 to a point which is approximately equidistant from shaft 304B' and 
304C'. In the preferred embodiment, pan 320 is slightly inclined 
downwardly from end portion 321 to portion 322 to facilitate the 
transmission of solution 20 downwardly for redeposit in receptacle 100. 
Subsequent to end portion 321 and from end portion 321 to shaft 304C', is 
stem shaker 330 (FIG. 6) which is designed to collect the stems, 
waterberries, mold, and other waste materials conveyed from solution 20 up 
first conveyor belt 310 and along hipped portion 315 to discharge point 
312. These materials are discharged into stem shaker 330 for transmission 
to a bin for storage and ultimate disposal (not shown). 
First conveyor belt 310 including hipped portion 315 is manufactured from a 
continuous wire mesh belt as described above. Since constant operation 
tends to plug the wire mesh belt, cleaning system 340 is provided to 
remove such materials from first conveyor belt 310. Cleaning system 340 
comprises three manifolds, 341 connected to a source of steam (not shown), 
342 connected to a source of water (not shown), and 343 connected to a 
source of compressed air (not shown). Cleaning system 340 is disposed 
within hipped portion 315 and above lower belt 315B and below upper belt 
315A. Each of the above manifolds 341, 342, and 343 may contain a series 
of nozzles (not shown) in fluid connection with said manifold to provide 
coverage for the entire width of hipped portion 315 of the wire mesh 
conveyor. 
Second conveyor belt 360, including hipped portion 365, is comprised of a 
continuous belt as described above with respect to first conveyor belt 
310. Discharge floor 107 acts to collect the solution which drips through 
the friar chain of first conveyor belt 360 up to the point where it 
becomes integral with side portions 101 of receptacle 100. Thereafter, pan 
370 is attached to conveyor frame 160 and extends outwardly from and 
inclining upwardly in parallel relation to second conveyor belt 360, to 
point 371. Thereafter it follows and lies in substantially parallel 
relation to hipped portion 365 for receiving droplets of solution 20 which 
drip through second conveyor belt 360. Pan 370 extends horizontally from 
point 371 to pan end 372, which lies substantially below shaft 304B-2" of 
second conveyor belt 360. Thereafter, dewater shaker 380 (FIG. 6) is 
disposed beneath hipped portion 365 and substantially parallel to hipped 
portion 365 whereupon the raisins which are transported from receptacle 
100 and up second conveyor belt 360 through hipped portion 365 are 
deposited into dewater shaker 380. Dewater shaker 380 also functions to 
receive materials removed from hipped portion 365 by cleaning system 390 
which comprises a series of manifolds 391 which may comprise for example, 
air, water and steam lines connected to respective sources, as described 
above (system 340) and which further comprise in each manifold 391, a 
series of nozzles (not shown) which distribute the respective substance 
across the entire width of wire mesh conveyor of hipped portion 365. 
Cleaning systems 340 and 390 both function to remove debris from the open 
mesh fryer chain of conveyor system 300, and prevent blinding, and 
plugging which promotes efficient use and reuse of solution 20. 
Referring now to FIG. 1, recirculating system 200 comprises suction box 210 
which is in fluid connection with solution 20 contained in receptacle 100 
and which is in fluid connection with recirculation pump 220 which pumps 
solution through fluid lines 230 and into manifold 240, the latter of 
which is in fluid connection with receptacle 100. 
More specifically, and with reference to FIGS. 2, 3, and 4, suction box 210 
lies substantially beneath discharge portion 150 of receptacle 100 and 
draws solution from receptacle 100. As is best seen in FIG. 5, suction box 
210 traverses the width of floor discharge 107 and thereby evenly 
withdraws solution 20 from receptacle 100 throughout its width. Suction 
box 210 comprises suction manifold 211 having side walls 212 integral with 
bottom walls 213. Bottom walls 213 slope downwardly from side walls 213, 
forming mouth 213A which is integral with suction line 214 which is in 
fluid connection with suction filter 215. Suction filter 215 operates, as 
is known, to remove extraneous materials finding their way into suction 
manifold 211 and is in fluid engagement with pump 220 which operates in 
conjunction with pump motor 225 to draw solution 20 from receptacle 100 
into suction manifold 211 through suction line 214 and suction filter 215 
and also operates to move solution 20 through solution line 330 into 
manifold 340 at a predetermined rate of flow. Pump 220 is designed to 
circulate solution 20 throughout recirculation system 200 and is a 
standard pump operating in a manner known in the art. Pump 220 therefore 
circulates filtered solution 20 through circulation lines 230 and into a 
"T" 231 which is in fluid connection with circulation line 230, then into 
valve 232, into manifold 240 and into manifold delivery 341. 
Manifold 240 includes controls (not shown) to regulate the rate of flow of 
the issuing stream of solution. Manifold delivery 241 is in fluid 
connection with manifold 240, the latter of which operates to uniformly 
distribute solution 20 at a uniform rate of flow throughout delivery 
manifold. Delivery manifold 241 is secured to receptacle 100 in receiving 
portion 140 thereof, in a position just beneath desired solution level 21. 
Manifold delivery 241, traverses the width of receptacle 100 and thereby 
uniformly distributes solution 20 throughout the width of receptacle 241. 
Delivery manifold 241 also contains a series of nozzles 243 in fluid 
connection with delivery manifold 241 for directing an issuing stream of 
solution 20 from the receiving portion 140 to discharge portion 150 of 
receptacle 100. 
As thus far described, solution 20 is fed into manifold 240 from 
circulation lines 230 and enters manifold delivery 241 whereupon solution 
20 is distributed evenly to nozzles 243, which produce a uniform issuing 
stream of solution 20 throughout the width of delivery manifold 241 and 
therefore, receptacle 100. In the preferred embodiment, manifold 240 is 
connected to manifold delivery 241 by a pair of slip joints 247. The slip 
joints 247 adjustably attach to and are in fluid relation with manifold 
delivery 341. Slip joints 247 permit nozzles 243 to be rotated by 
adjustment lever 248 through an arc preferable of at least about plus or 
minus 25 degrees from the position where nozzles 343 direct a 
substantially horizontal issuing stream of solution which is parallel to 
receptacle floor 106. This position is designated as zero degrees and the 
adjustment is hereafter designated by degree inclination of manifold 240. 
In this manner, adjustment level 248 may be utilized in the operation and 
while processing raisins to instantly adjust the issuing stream of 
solution 20, and more accurately separate the raisins from the cap stems, 
stems, waterberries, mold, and other waste materials. 
Referring now to FIG. 1, it can be seen that the apparatus of the present 
invention further includes baffle plate 170 secured to receiving floor 105 
of receptacle 100 at baffle weld 175. Baffle 170 is welded to receiving 
floor 105 in a manner such that it slopes downwardly from baffle weld 175 
towards receiving portion 361 of second conveyor belt 360. In this manner, 
as raisins or other heavier materials are deposited into receiving portion 
140 of receptacle 100 and sink towards receptacle floor 106, they will be 
received by baffle 170 which traverses the width of receptacle 100 and 
will thereby be directed to second conveyor belt 360. It is to be 
understood that baffle 170 is an optional feature. It has been found that 
it provides a convenient means of removing the materials from receptacle 
100. In the preferred embodiment, 1" manifold 275 is placed in fluid 
connection with receptacle 100, above baffle 170. Manifold 275 contains a 
plurality of 3/8 inch nozzle openings with the nozzle openings being 
directed along and in substantially the same inclination or slope as 
baffle 170. Manifold 275 is in fluid connection with "T" 231 which is in 
fluid connection with feedline 276 flowing through valve 277 and into 
manifold 275. In the preferred embodiment, manifold 275, is constructed of 
a material inert with solution 20, (i.e. stainless steel), and operates to 
evenly distribute solution 20 throughout the nozzles of baffle 275. 
In the operation of apparatus 10, valve 277 is closed throughout its 
operation and while manifold 240 is in operation. Valve 277 is opened at 
the termination of processing operations, or when otherwise needed to 
force any raisins or other materials received by baffle 170 onto the 
second conveyor belt 360 for removal from receptacle 100. 
Apparatus 10 further includes hoist 400 which functions to raise conveyor 
belts 300 out of and from receptacle 100. Hoist 400 comprises winch 410 
secured to frame 11 and utilizes cable 415 and a series of pulleys 420 
(not all of which are shown). Cable 415 passes through pulleys 420 and is 
secured to cable anchors 412 which are secured to conveyor frame 160. 
Winch 410 may be activated by winding same to remove conveyor belts 300 
from receptable 100 by pivoting same about shaft 450 which is integral 
with frame 11 and conveyor frame 160, as is best shown in FIG. 4. (See 
dotted lines). 
In the preferred embodiment, first conveyor belt 310 is disposed within 
receptacle 100 to properly receive a portion of the free flowing materials 
such as mold, waterberries, and other waste. In many instances, however, 
slight adjustment of the position of first conveyor belt 310 would yield a 
substantial improvement in the liquid separation of the free flowing 
materials. First conveyor belt 310 is therefore provided with plow 350 
which is integral with and supported by shaft 351, supported by frame 160 
and secured in pivotal relation with plow end portion 352. End portion 353 
of plow 350 is integral with a pair of adjustment rods 354 which are in 
threaded relation with end portion 353 and brackets 355 which are 
removably secured to rail 101. In operation of apparatus 10, plow 350 may 
be adjusted to the desired inclination, preferably plus or minus 20 
degrees from its horizontal or zero degree position which is defined when 
plow 350 is substantially parallel to floor 106. 
A negative inclination for manifold 240, as well as plow 350, indicates 
that each is adjusted or directed pivotally from their zero degree 
position toward floor 106. 
As is described above, frame 11, and other external structures are 
fabricated from structural steel. In the preferred embodiment, the 
internal portions of receptacle 100, conveyor belts 300, manifolds and 
nozzles associated with manifold 240 and 275 including the related 
internal structure, baffle 170 and recirculating feed 230 are all 
fabricated of stainless steel. The nozzles are standard orfice nozzles and 
in the preferred embodiment have 3/4" nozzle openings on 4" centers. 
Apparatus 10 may typically have the following dimensions for processing 
raisins at the stated tonnage per hour: 
______________________________________ 
4 T.P.H. 10 T.P.H. 
______________________________________ 
Receptacle Length: 10' 10' 
Receptacle Width: 36" 80" 
Receptacle Height: 36" 48" 
Floor ( 106) Length: 12' 14' 
Depth of Plow (below rails 101), 
0.degree. Inclination: 
8" 8" 
Depth of Manifold Nozzles (below rails 
101), 0.degree. Inclination: 
2" 2" 
Depth of Receiving Portion (below 
tails 101), of First Conveyor Belt: 
6" 6" 
Depth of Receiving Portion (below 
tails 101), of Second Conveyor Belt: 
30-36" 30-36" 
Distances A, B, and C from Manifold 
Nozzles 
to Receiving Portions of Second Con- 
veyor 
Plow, and First Conveyor: A = 30"; C = 30-40" 
B = 36", 
______________________________________ 
To operate apparatus 10 in the most economical manner, solution recovery 
system 500 was developed. Referring to FIG. 6, it is seen that the raisins 
discharged from second conveyor belt 360 by hipped portion 365 onto 
dewater shaker 380 are treated by a series of dewater shaker tables 380 
which in the preferred embodiment are "Syntron" tables, as are known in 
the art, preferably having a stainless steel bed. The action of shaker 
tables 380 promote removal of much of the separating fluid solution 20 in 
its original form, which is caught in pans (not shown) and may be 
collected and/or transported back to receptacle 100. In the preferred 
embodiment, there are a series of two shaker tables 380 designated as 
380A, and 380B. As is illustrated, discharge portion 380A-1 and shaker 
table 380B are provided with a series of manifolds 382 and 384, thereover, 
supplying alternatively a fine mist of solvent, which in this case is 
water (382), followed by high velocity air jets (384) disposed in 
alternating relation thereafter. While manifolds 382 and 384 are 
illustrated as a single manifold unit, it is to be understood that each 
may represent a cluster of such mist or air manifolds. Finally, the 
raisins are treated with a bank of air jets (386) at discharge portion 
380B-1. Each manifold provides a plurality of nozzles to cover the entire 
width of shaker tables 380. Shaker table 380A-1 and 380B also contains 
pans (not shown) to collect the rinse by the fine mist sprays and air 
jets. While this solution must be reconstituted, it has been found that by 
utilizing a fine mist of approximately three gallons per nozzle, per hour 
an ample amount of rinse and recovery of separating fluid solution is 
obtained without substantial reconcentrating. 
The Method 
In operation of apparatus 10, as thus far described, reference is now made 
to FIG. 6. FIG. 6 is a schematic view showing apparatus 10 as is 
incorporated "in-line" in a processing system for processing raisins. In 
processing of raisins, in apparatus 10, the raisins are passed through 
conveying station 3, then to conveyor 5 which is adjusted to properly feed 
materials into receptacle 100. 
Thereafter, the materials of first conveyor 310 are discharged onto shaker 
table 330 and the materials of second conveyor 360 are discharged onto a 
series of dewater shaker tables 380 where they are treated and then once 
again, passed through fluming station 3 by discharging same on product 
feed line 600. 
The materials discharged into receptacle 100 are those which may be 
characterized as materials which are loose and separable from the actual 
vines and may consist of some fruit with cap stems attached and some fruit 
with wood chips and other waste materials adhering thereto, but, for the 
most part, the raisins are separated from the other constituents which 
include stems, cap stems, wood chips, and other waste materials. Conveyor 
5 transports the free flowing materials to a point which is disposed over 
the receiving portion 140 of receptacle 100 and at a critical and 
predetermined height above solution level 21. The free flowing fruit is 
thereby thrust into solution 20 at a velocity which promotes immersion 
into solution 20 in a manner to promote separation by specific gravity 
differential. 
It is to be understood that the apparatus 10 of the present invention may 
be placed in various positions, "in-line" in the processing system for 
production of raisins. Typically, raisins are processed from grapes which 
are dried in the field and are then transported to wooden pallet bins for 
further drying. Thereafter, the processing of raisins occurs generally in 
the following steps: 
(A) The raisins are initially cleaned in various mechanical apparatus, such 
as, tumblers, rolls, etc; 
(B) They are subsequently processed by air cleaners; 
(C) And in some instances, processed by using maximum air cleaning 
concentrated "blows"; 
(D) They then may be washed in water baths and dried; and/or 
(E) They are finally prepared for marketing, which in certain instances 
includes application of oil, and/or sugars. 
In the examples which follow, raisins will be obtained at various points in 
their processing and designated as to what point they were obtained and 
treated by apparatus 10. Regarding step (C), it will be understood that 
when fruit to be used for commercial or industrial use is cleaned by 
violent air currents, 50% of the resultant product is very clean raisins 
and 50% is fruit containing a high proportion of unwanted extraneous 
matter. The clean fruit is generally separated from the dirty or "blows" 
and may be proessed in apparatus 10; likewise, the "blows" may be 
separately treated by apparatus 10. 
As thus far described, apparatus 10 may be placed "in-line" after the above 
mentioned processing steps and the free flowing fruit conveyed to and 
discharged in the receiving portion 140 of receptacle 100 and removed by 
conveyor belts 300 whereby stems, cap stems, waterberries, and other waste 
materials are transported to bins for disposal and/or storage. In the 
preferred embodiment (seen in FIG. 6) the cleaned raisins, the product of 
second conveyor belt 360, are transported to solution recovery system 500. 
It has been found that by thrusting the loose fruit into a solution of 
predetermined density, subjecting it to an issuing stream of solution from 
manifold 240, and maintaining the material in receptacle 100 for a 
predetermined dwell time, that the aforementioned constituents of the free 
flowing material seek predetermined levels within solution 20 and be 
separated and removed by conveyor belts 300. 
Apparatus 10 may be "fine tuned" to promote a greater degree of separation 
in its operation. Adjustments are made while processing raisins by 
changing the following parameters: inclination of and/or rate of flow of 
the issuing stream of solution, the inclination of plow member 350, and/or 
the specific gravity of solution 20. Since and to the extent that the 
separation of constituents is effectuated by differences in specific 
gravity of the constituents and the solution 20, and given the relative 
difficulty in altering the specific gravity of solution 20, it is more 
desirable to adjust the above inclinations and flow rates, either 
individually, or in any combination of effectuate a change in the manner 
in which the free flowing materials react when immersed in solution 20. 
These adjustments are critical to the efficient operation of the present 
invention and may compensate for differences in temperature of solution, 
specific gravity of solution, and materials, feed rate of materials, and 
the like. It is to be understood that rigid control of the specific 
gravity of solution 20 would obviate these type of adjustments, but, since 
exact control of the specific gravity of the solution is difficult and 
since the specific gravity of the materials varies from lot to lot the 
aforementioned means for adjusting the apparatus provides an effective and 
efficient way to compensate for such changes, without shuting down. 
In discussing the critical parameters of the present invention, it is to be 
understood that such parameters have general application to the separation 
of various materials. While they are discussed with reference to the 
processing of raisins and while limitations found to be best with respect 
to raisin processing are specifically set forth, it will be understood 
that the specific limitations found successful with respect to raisins, 
will change when applying the principles of the present invention in 
separation of other materials all within the scope of the present 
invention. 
Heighth of Conveyor 15 
It has been found that it was preferable for the free flowing materials to 
obtain a particular velocity prior to contacting solution 20 contained in 
receptacle 100. Generally it was found that the liquid separation of the 
materials are promoted by adjusting the height of conveyor 15 over 
solution level 21, to a point where the free flowing materials were caused 
to break apart and immerse themselves or sink into the solution, upon 
contacting solution 20. This critical velocity was not emperically 
calculated since it is interrelated with the specific gravity of the 
solution, the specific gravity of the constituent materials, the feed rate 
of the materials into receptacle 100, as well as the flow rate of the 
issuing stream of solution within receptacle 100, and the like. In the 
preferred embodiment, a heighth of about 18 inches or greater produced the 
most desirable results, given a specific gravity of waste materials of 
about 1.19 or less and that of raisins of about 1.28 or more. The upper 
limit of height will be determined based upon the maximum heighth which 
the materials could be accurately discharged into receiving portion 140 to 
properly interact with the issuing stream of solution to cause dispersion 
of the materials (testing indicated that proper interaction still occurred 
at a height of 36"). 
Type of Solution, Specific Gravity and Issuing Stream Parameters 
It has been found that by regulating the specific gravity of solution 20 
that constituent materials having only slight differences in specific 
gravity may be separated. In determing the specific gravity of the 
solution, the specific gravities of the various constituents of materials 
to be separated are calculated or approximated and the specific gravity of 
the solution is set such that certain of the materials become more buoyant 
and tend to float toward solution level 21, while the materials having a 
greater specific gravity tend to sink toward floor 106. For example, the 
specific gravities of raisins ranging from Greek-tunnel dried to fruit to 
be used in breakfast cereals, to Thompson seedless and the like are 
approximately 1.28 to 1.32 or greater. On the other hand, the average 
specific gravity of the heaviest stems are generally about 1.19. The 
specific gravity of the solution in the above example, therefore, would be 
set within the range of approximately 1.20 to 1.27. Preferably, the 
selected specific gravity of solution 20 would be in the middle of the 
aforementioned range or about 1.24. This would tend to produce an 
environment in which the raisins would quickly sink to the bottom while 
the stems would posses more buoyant properties and, therefore, tend to 
rise quickly toward the solution level 21. It is to be understood that 
solution 20 may comprise any type of solution having the required specific 
gravity, and, of course, being compatible with the end product being 
processed. Suitable solutions in the production of raisins include: 
sucrose, glucose, levulose, maltose, sodium chloride, calcium chloride, 
molasses, fruit juices, fruit extracts, or other saccharide. While it is 
preferable that saccharide type solutions be utilized in raisins, insofar 
as their compatibility with the final raisin product, the critical 
parameter is the specific gravity of the solution and not the type of 
solution. It may for example, be more preferable to utilize various saline 
or protein or emulsions solutions in applying the liquid separation 
process of the present invention to various vegetable separations, chicken 
from bone and gristle, and the like. In the processing of raisins, it has 
been found that the apparatus 10 of the present invention is successfully 
operated in a solution range of about 30 to 50% Brix or a specific gravity 
in the range of approximately 1.15 to 1.35. It was found that these ranges 
provided a suitable mode or environment for the liquid separation of the 
raisins from the other materials notwithstanding the above range was not 
within the specific gravities of the constituents (i.e. stems approx. 
1.19--raisins approx. 1.28). This discrepancy is explained by the 
fine-tuning of apparatus 10 as described above. 
As thus far described, the free flowing materials contact solution 20 which 
is issued from manifold 240 and described hereinabove as an issuing stream 
of solution. Solution level 21 is preset and in the preferred embodiment 
is aproximately 6 inches above plow 350 measured from an inclination of 
0.degree.; or approximately 1 to 2 inches above the issuing stream of 
solution measured from an inclination of manifold 340 of 0.degree.. It has 
been found that given the selected solution at predetermined specific 
gravity and the aforementioned velocity of the free flowing materials that 
a particular dwell time is required; is defined as the time necessary to 
effectuate the separation of constituent materials. While this parameter 
is interrelated with the aforementioned combination of parameters, above, 
in the preferred embodiment, the rate of flow of the issuing stream of 
materials is set to yield a sufficient dwell time to effectuate sufficient 
separation of the constituent materials by controlling the flow rate of 
the issuing stream. This is readily adjustable and controlled by the 
operator of apparatus 10 through adjustment of pump speed control (not 
shown) of pump 220. In processing of raisins it was found that an issuing 
stream of about 100 to 120 gallons per minute provided a sufficient dwell 
time. The preferred range was 115 gallons per minute. Likewise, control of 
the angle of inclination of manifold 240 also effects dwell time. By 
directing the issuing stream more toward receptacle bottom 106 (a negative 
inclination) the operator in effect increases the dwell time of the 
materials in solution 20; contrariwise, if the issuing stream is directed 
more towards solution level 21 (a positive inclination). 
As was stated above, the operator may further fine-tune appartus 10 by 
adjusting plow 350. Much the same as manifold 240, above, and therefore, a 
similar explanation of his operation will not be repeated. 
A dwell time of about 20 seconds was found to be acceptable. 
The following examples are set forth to more clearly illustrate the 
principles and practices of the present invention to one skilled in the 
art. They are not intended to be restrictive, but are merely illustrative 
of the invention. 
EXAMPLE 1 
Initial testing was performed to prescreen the operational variables and 
determine various places where apparatus 10 would be most effective when 
placed "in-line" in a raisin processing system. Tote pan quantities of 
approximately 30 pounds per tote pan where hand-fed into apparatus 10 at a 
feed rate corresponding approximately to a commercial feed rate of 4 tons 
per hour. 
Raisins were taken from various steps of their processing, corresponding to 
materials after processing as in steps A through E. The results of these 
tests are summarized in Table 1 below. The data reflects the most 
effective performance obtained, insofar as stem removal and the variable 
conditions recorded at the time of its achievement. The percent total 
yield was disproportionally low in these prescreening evaluations, 
however, later testing (see following examples), on a commercial scale, 
achieved significantly greater yields. 
It was concluded that the best opportunities for production of commercial 
quantities of raisins would be obtained by placing apparatus 10 "in-line" 
after processing as in steps B through D. 
TABLE I 
__________________________________________________________________________ 
"B" After Air 
"A" After Initial 
Cleaners, but Before "D" Washed 
Cleaning, Before 
Washing, Normal 
"C" same as "B" but 
Berries Greek 
"E" Cereal Raisins 
Air Cleaners, 
Settings on 
Maximum Air Cleaning 
and Tunnel 
Just Prior to Oil 
Operating Conditions 
or Wash Air Cleaners 
concentrated "Blows" 
Dry Blend 
Application 
__________________________________________________________________________ 
Solution Flow Rate 
117 gallons/min. 
117 gallons/min. 
117 gallons/min. 
117 gallons/min. 
117 gallons/min. 
Time in Solution 
20 sec. 20 sec. 20 sec. 20 sec. 20 sec. 
Manifold Jet Inclination 
2.degree. Negative 
2.degree. Negative 
5.degree. Negative 
5.degree. Negative 
8.degree. Negative 
Plow Inclination 
0.degree. 
0.degree. 9.degree. Negative 
18.degree. Negative 
18.degree. Negative 
Specific Gravity of 
Solution 1.232 1.280 1.282 1.282 1.285 
Solution Temperature, .degree. F. 
59 62 62 61 62 
Specific Gravity of 
Raisins 1.32 + 1.30 + 1.32 + 1.30 + 1.32 + 
Stems per 6 pounds, 
before separation 
464 27 546 34 5 
Stems per 6 pounds, 
after separation 
1.4 0 14 0 0 
Effectiveness of Stem 
Removal, Percent 
99.7% 100% 97.5% 100% 100% 
Total Yield, 
Percent 94% 71% 72% 82% 98% 
__________________________________________________________________________ 
EXAMPLE 2 
10,080 pounds of cereal berries which had been rejected at the production 
line by quality control, were processed utilizing apparatus 10. A 
solution, derived from raisin extract was utilized. Feed was at a rate of 
5.81 tons per hour. The materials discharged from first conveyor belt 310 
had the following composition: 
______________________________________ 
% of % of 
Count Pounds Rejects Total Bin 
______________________________________ 
Stems 5617 1.83 9.0 0.169 
Waterberries, Mold 
and Substandard 
-- 12.96 64.0 1.200 
Good Berries -- 5.46 27.0 0.506 
Sub Total -- 20.25 100.0 1.875 
______________________________________ 
The materials discharged from second conveyor 360 had the following 
composition: 
__________________________________________________________________________ 
Estimated Count 
% of Process- 
% of original 
Count per 
in lot, extrap- 
Pounds in 
ed bin, sep- 
bin before 
6 lb. sample 
olated bin lot 
arated separation 
__________________________________________________________________________ 
Stems 4 706 0.26 
0.025 0.024 
Waterberries, 
Mold and 
Substandard 
-- -- 48.76 
4.6 4.5 
Good Berries 
-- -- 1010.0 
95.4 94.0 
Sub Total 
-- -- 1060.02 
100 98.52 
Total, rejects and separated 100.4 
__________________________________________________________________________ 
The results of separation utilizing apparatus 10 as outlined above are set 
forth in Table II below. 
TABLE II 
______________________________________ 
Solution Flow Rate 117 gallons/min. 
Dwell Time (Time in Solution) 
20 sec. 
Manifold Jet Inclination 
0.degree. 
Plow Inclination 0.degree. 
Specific Gravity of Solution 
1.244 
Solution Temperature .degree. F. 
62 
Specific Gravity of Raisins 
1.32 
Stems before Separation 
5,617 
Stems after Cleaning 706 
% Effectiveness of Stem Removal 
87.5 
total pounds waterberries, mold, 
substandard in bin: 
(a) Before Cleaning 61.72 
(b) After Cleaning 48.76 
(C) Percent Removal 79% 
Total Good Berries: 
(a) Before Separation 1,016.5 
(b) After Separation 1,011.0 
True Yield Percent 99.5% 
______________________________________ 
EXAMPLE 3 
A lot of 1,080 pounds of cereal berries which had been rejected at the 
production line were processed utilizing apparatus 10 under the same 
conditions as above with respect to Example 2, with the only change being 
that the plow was adjusted to an inclination of negative 18% to obtain a 
greater separation by increasing the materials collected on first conveyor 
belt 310. It was found that the true yield was a more realistic 98% and 
the processing resulted in a stem removal effectiveness in the order of 
about 95% and a mold, waterberries and substandards effectiveness in the 
order of about 65%. 
In summarizing the data obtained in Examples 1, 2, and 3, it has been found 
that apparatus 10 will preferably be adjusted to obtain a yield in the 
order of from about 97 to 98% which in turn means that more good berries 
or raisins will be conveyed with the waste material up first conveyor belt 
310 (approx. 2 to 3%). A slight decrease in the true yield, for example, 
has been found to result in a higher effectiveness of removal of stems, 
waterberries, mold, substandards, and other waste. 
EXAMPLES 4 THROUGH 10 
Apparatus 10 was used to process the following lots of raisins as 
described, hereinbelow, at a specific gravity ranging from 1.20 to 1.28 
with solution level 21 held at 2.5 inches below rail 101, utilizing a plow 
inclination of negative 2.degree. and an inclination of manifold 240 of 
negative 10.degree.. Other parameters, including the solution flow rate, 
dwell time, and solution temperature, were maintained as were set forth 
hereinbefore in Table II (with respect to Example 2) except as otherwise 
indicated. Each of the following examples have been summarized in Table 
III below. 
EXAMPLE 4 
Cereal raisins were processed (raisins after good cleaning but before 
washing) with moldy fruit being added to the lot. First conveyor belt 310 
removed 4.5 pounds of raisins, trash and stems and 6 pound sample of 
separated cereal raisins from second conveyor belt 360 was found to 
contain no (0) stems, 6 grams of mold, and 1 cap stem. The 4.5 pounds of 
material conveyed by first conveyor belt 310 were found to contain 807 
stems, 1.1 pounds of mold, and substandard, and 3.2 pounds of good cereal 
berries. Before processing, the apparent stem content was on the order of 
4 stems per 6 pounds; after processing, 0 stems per 6 pounds. 
EXAMPLE 5 
A 1,200 pound lot of raisins after good air cleaning and washing, was 
processed by apparatus 10 under the following conditions. The plow 
inclination was negative 3.degree., the inclination of manifold 240 was 
negative 4.degree. and the solution temperature was 78.degree.. The stem 
count prior to separation was 30 per 30 pound sample; and after 
separation, the count was 3 per 30 pound sample. A total of 1,154 stems 
were removed: 26.75 pounds of stems, waterberries, and mold were removed 
by the unit. 
EXAMPLE 6 
The materials removed by second conveyor 360 in Example 5, above, were 
rerun in apparatus 10, after the specific gravity of the solution was 
raised to 1.26. The results of the separation indicated that an additional 
28 stems, several waterberries, but no appreciable good berries were 
removed. At 3 stems per 30 pounds of sample, there would have still been 
118 stems in the cleaned berries resulting from Example 5 and rerun 
herein. Removal of 28 more stems would therefore reduce the number of 
stems to 90, and indicate 2.5 stems per 6 pound sample (0.5 stems per 6 
pound sample). 
EXAMPLE 7 
Another lot of raisins after cleaning and washing, were processed in 
apparatus 10 as in Example 5, above, but at a specific gravity of 1.260. 
The feed rate was equal to 3 tons per hour. Prior to separation, the lab 
samples indicated 22 stems per 30 pound sample and after separation, the 
lab count indicated no (0) stems per 30 pound sample. 
EXAMPLE 8 
A lot of 1,200 pounds of the type raisins processed in Example 7 were 
processed under the same conditions as Example 7 and at a feed rate of 4 
tons per hour. Prior to separation, lab samples indicated 17 stems per 30 
pound sample and after processing, the count was zero (0) stems per 30 
pound sample. 
EXAMPLE 9 
A 1,200 pound batch of raisins which had been subjected to good air 
cleaning yet had not been washed, were processed in apparatus 10 at a feed 
rate of 3.0 tons per hour and in a manner of Example 8, above, except that 
the solution had a specific gravity of 1.28. 
EXAMPLE 10 
A 1,200 pound lot of raisins of the type in Example 9 were processed under 
conditions of Example 8 at a rate of 3.5 tons per hour and in a solution 
having a specific gravity of 1.26. 
______________________________________ 
Examples 4 5 6 7 8 9 10 
______________________________________ 
Feed Rate, 
Tons per Hour 
5.9 2.0 2.0 3.0 4.0 3.0 3.5 
Specific Gravity 
Solution 1.20 1.234 1.26 1.26 1.26 1.28 1.26 
Pounds of Berries 
Processed 1179 1200 1176 1100 1200 1200 1200 
Yield 99.6 98.0 -- 98.0 95.0 98.0 98.5 
Number of 
Stems 
Removed 807 1182 28 806 680 500 520 
Percent 
Effectiveness 
of Stem 
Removal 100 90 -- 100 100 98 93 
______________________________________ 
*See Test of Example 6 
The above examples indicate that apparatus 10 as applied to the method of 
the present invention can be utilized in a highly effective manner for 
removal of stems; and additionally, mold, waterberries, and substandard 
defects, heretofore not removed in raisin processing. Moreover, chips of 
pallet-bin wood, were removed and additionally, it was found that 
cello-overwrap, cardboard fiber, and the like, were also removed. 
It will be appreciated that the numerical values and ranges hereinbefore 
set forth in the examples are representative only of typical values and 
ranges which have been found to be acceptable in the method and apparatus 
as applied to raisin processing. Generally, the method and apparatus of 
the present invention is applicable to various forms of separation of 
materials as per the general relationships set forth hereinbefore. It 
will, of course, be obvious to those skilled in the art, that various 
modifications may be made in the method of the present invention and in 
the apparatus with which it is used without deparating from the spirit and 
scope of the present invention as set forth in the appended claims.