US3905124A

US3905124A - Grain drying process

Info

Publication number: US3905124A
Application number: US504663A
Authority: US
Inventors: Robert P Cooper
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-11-19
Filing date: 1974-09-09
Publication date: 1975-09-16
Anticipated expiration: 1992-09-16

Abstract

In a grain column drier, a plurality of cooperating vertically and horizontally spaced distributing units automatically and continuously treat all the parts of the grain mass passing through the grain column mass by structure utilizing the angle of repose characteristics of grain mass at low velocity to help support the grain and without constricting the cross sectional available for flow of material through the column to provide uniform and efficient gas contact with all surfaces of the grain particles by exposing each particle of grain in each vertically extending grain column segment to contact drying air moving in three different mutually perpendicular planes.

Description

United States Patent 1 H11 3,905,124

Cooper Sept. 16, 1975 1 1 GRAIN DRYING PROCESS [76] Inventor: Robert P. Cooper, Rt. 1, PO. Box Primary EXaminer'TJPhn Cawby 151 Amarillo 79106 I Attorney, Agent, or Firm-Ely S11verman [22] Filed: Sept. 9, 1974 1 1 ABSTRACT [21] Appl. No.: 504,663

Related US. Application Data Kleinberg 34/171 In a grain column drier, a plurality of cooperating vertically and horizontally spaced distributing units automatically and continuously treat all the parts of the grain mass passing through the grain column mass by structure utilizing the angle of repose characteristics of grain mass at low velocity to help support the grain and without constricting the cross sectional available for flow of material through the column to provide uniform and efficient gas contact with all surfaces of the grain particles by exposingeach particle of grain in each vertically extending grain column segment to contact drying air moving in three different mutually perpendicular planes.

3 Claims, 23 Drawing Figures PATENTEU SEP I 6 I975 \Q I M PATENTED SEP 1 s 1975 sum u 0? 7 FIG. /3

PATENIHJSEP m 3,905,124

sum 8 0F '1 FIG/4 AAA (D C AAA H615 AAA AAA AAA F/G/7 w FIG/8 AAA AAA FIG/9 A A A l620 AAA AAA GRAIN DRYING PROCESS CROSS REFERENCE TO RELATED APPLICATIONS:

This application is a division of my co-pending application Ser. No. 416,739 filed Nov. 19, 1973, now US. Pat. No. 3,864,845.

BACKGROUND OF THE INVENTION:

1. THE FIELD OF THE INVENTION The field of invention to which this invention pertains is grain drying in column driers.

2. DESCRIPTION OF THE PRIOR ART Prior art column driers, while economical to construct, regularly produce damage to grain treated thereby resulting from the high temperature applied by the drying and heating gases to the portions of the grain directly and continuously exposed thereto while other portions of grain mass moved through thereto while other portions of grain mass moved through the grain columns were incompletely dried. Moisture analysis based on overall moisture content of the grain mass did not distinquish between the composite of overdried and underdried product increments and accordingly resulted in discharge from the drying columns of sufficient amount of grain particles of undersirable amounts of moisture to create heating problems in storage bins to which such grains were passed following treatment in such driers, which condition necessitated further cycling of such grain to the drier with added expense of heating for such drying as well as grain spoilage.

SUMMARY OF THE INVENTION Each rear portion of grain adjacent the outlet screen the inlet screen while supporting an upwardly exposed surface of that grain mass at its angle of repose directly to the hot air stream and directly passing hot air to that upwardly exposed grain surface and through the grain therebelow; and thereafter moving the said first rear portion of grain mass downward of the column along the inlet screen while exposing a vertical surface of said mass to the hot drying air, and then passing the originally front portion of the grain theretofore moved to and adjacent the outlet screen towards said inlet screen while supporting and upwardly exposing a surface of that grain mass at its angle of repose directly to the hot air stream and directly passing hot air through that upwardly exposed grain surface and through that grain mass to provide uniform and efficient gas contact with all surfaces of the grain particles by exposing each particle of grain in each vertically extending grain column segment to contact drying air moving in three different mutually perpendicular planes. The apparatus for this drying improvement is similarly applied to the cooling section to there likewise improve the efficiency of gas solid contact.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 is an overall view of the installation assembly 30 of which the grain dryer of this invention is a part.

FIG. 2 is an enlarged broken away view of zone 2A of FIG. 1, broken away along the section 2B-2C-2D of FIG. 3.

FIG. 3 is a vertical longitudinal cross-section of the grain treatment apparatus 33 through section 3A3A of FIG. 2.

FIG. 4 is a side perspective view of an empty turning assembly 50.3 seen along direction of arrow 4A of FIG. 5.

FIG. 5 is an end view partially in perspective as seen along the direction of arrow 5A of FIG. 4.

FIG. 6 is a phantom isometric view of the apparatus 50 shown in FIGS. 4 and 5 with phantom showings of the locations of grain surfaces located in such structure and their movement during the operation of the grain treating apparatus 33.

FIG. 7 is a diagrammatic top view along direction of arrow 7A of FIG. 8 of the turning assembly 50.3 shown in FIGS. 4-6 during the operation of the apparatus 33 to show identified locations of portions of grain located in the units 50.3 during the passage of such portions of grain during the operation of the assembly.

FIG. 8 is a diagrammatic vertical section diagrammatically showing the location and movement of some of the portions of the grain shown in FIG. 7 during the operation of grain treating apparatus 33; this view is a vertical section along the section 8A8A of FIG. 7.

FIG. 9 is a diagrammatic vertical section along section 9A9A of the FIG. 7 to show the location and path of movement of some of the portions of grain shown in FIG. 7 during operation of the grain treating apparatus 33.

FIG. 10 is a diagrammatic horizontal section at section to show the distributions of the particles in FIGS. 8 and 9 at the level 10C-10C of FIGS. 8 and 9.

FIG. 11 shows distribution of particles at level 11A of FIGS. 8 and 9 during the operation of the grain apparatus 33'.

FIG. 12 is an overall diagrammatic exploded view of the separate overlapping paths of movement of adjacent inner and outer zones of the grain mass in the column 42 of apparatus 33 and the relative location of portions of such zones at different vertical positions in column 42.

FIGS. 13-20 are diagrammatic representations of the location of the portions of grain at positions 13A-20A, respectively, of FIG. 12 and shown in plan view.

FIGS. 21A-F diagrammatically illustrate the shape and size of the horizontal cross section area available in unit 55 of assembly 50 at levels 21A-21F shown in FIG. 4.

FIG. 22 is a diagrammatic longitudinal and vertical cross section through column 42 along a vertical section corresponding to the vertical plane 22A22A of FIGS. 2 and 6.

FIG. 23 is a isometric diagrammatic representation of grains in the mass 80 adjacent grid 52 at zone 23A of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT:

trucks as 34A and/or trains loaded with grain to empty such grain at the location of the assembly 30 whereby to transfer grain to the bins as 31A by conduits as 35D,

and, also, for transfer of grain to empty trucks whereby the full cycle of bringing grain to the storage facility and discharging from the storage facility to a transport media as 34A is accomplished. Trucks are illustrated but transport media could be railroad cars as well. I

The dryer assembly 33 comprises a vertically extending interior chamber, 40, in an exterior housing, 41, and a plurality of

grain treatment columns

42 and 42A and heating fan assembly 58 and a cooling fan assembly 59.

Housing 41 comprises vertical front and rear walls 41.1 and 41.2 and vertical left and right side walls 41.3 and 41.4

The front and rear walls 41.1 and 41.2 of the housing 41 and the left and

right columns

42 and 42A define a vertically extending gas input chamber 40. A horizontal imperforate baffle 43 separates the chamber into a lower cooling section 44 and upper drying section 45.

Vertically extending

exhaust spaces

46 and 46A are located between the exterior surfaces of the

columns

42 and 42A and walls 41.3 and 41.4. Vents 47 and 47A in the upper end of the lateral wall of the housing 41.3 and 41.4 provides for exhaust of moisture laden air.

Discharge conveyors

48 and 48A at the bottom of the

column

42 and 42A, respectively, discharge the treated grain into the boot or feed of the return conveyor 36, and are variable speed helical augers.

A garner bin 57 is located between walls 41.1, 41.2, 4l .3 and 41.4 at the top of the

columns

42 and 42A and the imperforate floor 57.1 thereof provides for distribution of the grain therein to the top of each of the

columns

42A and 42. The heater and fan assembly 58 comprises a heater fan 58.1, a heater 58.2 and a duct 58.3 with a discharge opening 58.4 in wall 41.2 operatively connected so that the discharge duct opening thereof enters the dryer section of the air chamber above the baffle 43; a cooling fan assembly 59 comprising a fan 59.1 and a duct 59.2 with an opening 59. 3 is arranged with its discharge duct 59.3 entering the chamber 40 below the baffle 43 in the cooling section 44 of the chamber 40 at the bottom end of wall 41.2 as

in FIG. 3.

The column 42 comprises a rigid open frame 25 composed of rigid spacedapart

vertical members

26, 26 rigid spaced apart horizontal members as 27 and 27' firmly joined together and defining grid frame spaces as 28 on inside 29 on outside, perforate flat inlet grid 52 in spaces 28, perforate flat outlet grid 53 in spaces 29 and turning

sections

50, 150, and 250. I

The frame 25 is a rigid frame extending vertically and located within the housing 41, the frame supports in the spaces at its interior face the inlet grid 52 and at its outer side of the outlet grid 53. The inlet grid and outlet grid are parallel to each other and in combination with the walls 41.1 and 41.2 of the housing 41, provides a grain space 54 of rectangular cross section within eachcolumn where through grain passes to be treated by warmed air or cool air from fans 58.1 and 59.1.

The column 42A comprises a rigid open frame 25A composed of rigid spaced apart vertical members 26A, rigid spaced apart horizontal members 27A firmly joined together and defining grid frame spaces as 28A on inside and 29A on outside perforate flat inlet grid 52 in space 28A, perforate flat outlet grid 53A in space 29 and turning

sections

50A, 150A, and 250A.

The frame 25A is a rigid frame extending vertically and located within the housing 41, the frame supports in the spacesat its interior face the inlet grid 52A and at its outer side the outlet grid 53A. The inlet grid and outlet grid are parallel to each other and in combination with the walls 41.1 and 41.2 of the housing 41, provides a grain space 54A of rectangular cross section within each column wherethrough grain passes to be treated by warmed air or cool air from fans 58.1 and The

columns

42A and 42 are mirror image alike structures. Each column as 42 is composed of a plurality of

like column segments

49, 149, 249 and 349 and like

turn assemblies

50, 150 and 250, with the turn assemblies located between the column sections (as shown in FIGS. 2, 3 and 22) and

screens

52 and 53 and supported on frame 25 members as 26 and 27.

Column 42 comprises a central portion 42.3, a front portion 42.1 and a rear portion 42.2 each formed of like units. Portion 42.1 is composed of the front grain column segment portions 49.1, 149.1 and 249.1 and 349.1 and turn units 50.1, 150.1 and 250.1.

In rear column portion 42.2 are similarly located the rear turn elements 50.2, 150.2 and 250.2 and the rear grain column segment portions 492, 149.2, 249.2 and 349.2 therebetween and in central portion 42.3 are located the central turn elements 50.3, 150.3 and 250.3 and the central grain column segment portions 49.3, and 149.3 and 249.3 therebetween and 349.3 therebelow.

The

turning assemblies

50, 150 and 250 are like in construction; the description accordingly given for assembly 50 applies to 150 and 150; however, the parts of assembly 150 are given referent numerals units higher than the referent numerals applied to the corresponding parts of unit 50, while the structure parts in unit 250 corresponding to the similar structures in assembly 50 are given referent numerals 200 units higher than the corresponding referent numerals for corresponding parts in unit 50.

One turning assembly 50 is located between the baffle 43 and the bottom 57.1 of garner bin 57 (the bottom 57.1 is the same as the roof of the drying or heating sections 45 of gas input chamber 40) with the top of such assembly 50 one-third of the distance between bottom of the gamer bin and the top of the baffle 43; another assembly is located with its top two-thirds of the distance between bottom of the gamer bin and the top of the baffle 43.

Each turning assembly 50 is composed of three structurally identical units 50.1, 50.2, 50.3 arrayed side by side as shown in FIG. 2. Each unit as 50.3 is composed of a pair of

identical sub-units

55 and 56 with a common median plate 68 adjacent portions of

screens

52 and 53 and plates 69.1 and 69.2.

Assemblies 50.1, 50.2, 50.1A and 50.2A and 50.3A are identical to 50.3 as are all the turn assemblies of assembly 33.

Each column segment as 49, 149 and 249 comprises the grids or screens 52 and 53 and the horizontal and vertical members of frame 25 forming a vertical rectangular sectioned rigid perforate container for a portion same horizontal rectangular cross section, and the same horizontal rectangular cross section as the turn assembly units in vertical line therewith (as 50.3, 150.3, 250.3, respectively).

In the following description of unit 50.3, the term central means in the direction of arrow 81 towards the central plate 68 of unit'50 (while forward and rearward are as shown in FIG. 2) lateral means in a direction away from the median plate 68, as shown by

arrows

82 and 83; right and left are as shown by

arrows

83 and 84, respectively, inward refers todirection of arrow 85 of FIG. 5 or movement toward chamber 40 from space 46 while outward, as shown by arrow 86 of FIG- 5 and means toward space 46' from chamber 40.

The referent numerals 101-126 refer to the points of intersection of edges or unit 50. Two of such points identify each of the lines and edges in FIG. 4 and 5, by indicatin'g'the line or edge between such points. These points are tabulated in Table I.

Column segment 49 extends from the level or surface at the top of column 42, immediately below garner bin 57 to the top level of the turn unit 50 and segment 149 extends between the

turn units

50 and 150 from a few inches below the bottom of the upper turn unit (as points 111-115 of unit 50.3) to the top level of the next turn unit 150. The top level of each turn unit, as 503, is a horizontal plane in which points as 106, 107, 108, 109, 125, 126 and 128 are located.

The right unit 56 comprises, in operative combination, a right upper lateral centrally sloped rigid flat smooth surfaced panel 61, a vertical right transverse triangular rigid flat smooth surface panel 62, an upper rear central laterally sloped rigid flat smooth surface panel 63, a rigid vertical right median panel 64, a lower right lateral inwardly sloped rigid flat smooth surfaced panel 65 and a lower right central outwardly sloped rigid flat smooth surfaced panel 66 firmly joined as shown in FIGS. 4, 5 and 6. As also shown in FIGS. 4 and 6, the leftturn unit 55 of unit 50.3 is composed of a left upper inner central laterally sloped panel 71 operatively connected at its bottom to the top of a vertically disposed left transverse rectangular panel 74 and a vertical left transverse triangular rigid flat smooth panel 72. The bottom of

panels

72 and 74 are each firmly attached to panel 74. The top of panel 74 is also firmly attached at its top to an upper rear lateral centrally sloped flat smooth surfaced panel 73. The panel 71 is attached at its bottom edge to the inner half of the top edge of the vertical left median panel 74; the bottom edge of panel 73 is attached to the rear half of the top edge of panel 74; left lateral outwardly sloped panel 76 and a left forwardly sloped panel 75 are firmly attached to the lower sloped edge of panel 74.

A right lateral support panel 67 is firmly attached to the lateral edge of the lower right lateral sloped panel A left lateral support panel 77 is firmly attached to the lateral edge of the lower left lateral sloped-panel 76.

The panels as 76 and 66 serve to support each unit as 50 on the horizontal frame members as 27 of the frame 51 of assembly 33.

Panels

61, 63, 71 and 73 are of equal size and have the same rectangular shape, rigidity, thickness and surface smoothness; also,

panels

65, 66, 75 and 76 are all of the same size and shape, rigidity, thickness and surface smoothness.

Panels

72 and 62 are of the same size and shape and

panels

64 and 74 are of the same size and shape. The top edges of

panels

65, 66, and 76 lie in the same horizontal plane and the bottom edges of

panels

65, 66, 75 and 76 are colinear and straight. Panel material is 1/ 16 inch imperforate steel sheet but may use screening at

panels

62, 72, 69.1 and 69.2, as shown in FIG. 4 also impervious to the grain treated.

The installation 30 provides a system for the proces of grain drying hereinabove described using the turning apparatus as 50 constructed and arrayed as above de scribed. Grain dryer 33 is an improved column grain dryer: the essential elements thereof are herein described in adequate detail for one of ordinary skill in the art to construct and use the apparatus and process according to this invention; details of the conventional structures in dryer 33 are set out in available literature and patents such as in Schanzer Co. Bulletins and handbooks. As the improvement provided by this invention lies in the structure of plurality of turning units as 50 and the operations therein and the operation of the system resulting from the use of such units, such structure and operation are set outin detail needed for one skilledin the grain dryer art to make and use such apparatus system and process.

In the overall operation of installation 30, grain stored in the bins 31A-G is tested and is passed into the grain garner bin 57 and slowly moves downwardly through the

columns

42 and 42A to the discharge augers 48 and 48A at a rate controlled by the rate of discharge of the discharge augers. Between the bottom of the gamer bin and the top of each section as 50, and between each of the turning

sections

50 and 150 and between turning

sections

150 and 250 and between section 250 and discharge auger 48, the particles of the grain moves through grain column portions as 49, 1 49, 249.and 349, at a steady rate (of one-fourth to onehalf) inches per second downward through the

columns

42 and 42A, depending on the setting of the rate of speed of the discharge augers as 48 and 48A and gates therefor.

During the downward travel of the grain through the

columns

42 and 42A, the hot air from the heating fan the heating fan assembly 58 passesinto the zone 45 and then through the screens 52 and 52Athrough a mass of the grain 80 to and through screen 53 and 53A, respectively, to the

exhaust spaces

46 and 46A and out wardly through the

vents

47 and 47A. As the ,grain moves in

columns

42 and 42A downwardly past the level of the baffle 43, the cool air in the cooling section space 44, passed thereto by the cooling fan assembly 59, passes through the inlet grid screen 52 and 52A to the

spaces

46 and 46A, respectively.

In operation of apparatus 33 on downward motion of the grain in each portion, as 42.0 of each column as 42, all of such grain particles moves in parallel vertical rectilinear paths in the vertically sequentially arrayed column portions as 49, 149 and 249, which column portionsare located between the

turn units

50, 150 and 250 and above turn unit 50 and below turn unit 250.

In each straight column segment, as 49, 149 and 249 and 349, representative adjacent grains, as 181-187 of mass 80 are diagrammatically illustrated in FIG. 23. In FIG. 23, reference points 19l197 define corner points of a rectangular prism 200 surrounding those grains l81187 for purpose of defining direction of movement of gas past such grains. A horizontal plane 188 is located at the level of points of contact between particles that are located one above the other, as grain 181 over grain 183, and as grain 182 over grain 184 and as grain 186 over grain 185. The vertical plane 199 is is parallel to inner grid or screen 52, while vertical plane 198 is perpendicular to inner grid or screen 52 and also perpendicular to plane 199. Adjacent particles at the same vertical level and distance from grid 52 as 181 and 182 and as 183 and 184 and as 186 and 187 are in contact at points generally located between the centers of such grains along the direction of or parallel to the line between

points

191 and 192 while adjacent grain particles as 181 and 186 and as 182 and 187 are in contact at points between the center of such grains and along the direction of the line between points 191 and 195, or parallel to such lines.

The vertical spacing between edge 123-124 above the edge 118-119 of panel 117 and rigid wall structure and horizontal space between panels 74 and 68 (edge 104-105 and 102-103 of unit 56) of unit 50 and units 50.1, 50.2, 150, 250, 50A, 150A and 250A) provide vertical support for the mass of grain above the level defined by the edges as 125-126 and 108-109 of unit 50.3. Thereby, unit 50.3 and the like units of apparatus 33 (50.1, 50.2, 50A, 150, 150A, 250, 250A) provide for an even rate of flow below the horizontal level of edges as 104-105, 105-110 (and 123-124 and 123-122) while the absence of constricted cross sectional area as shown in FIG. 21 to the downward passing of the grain through each unit as 55 and 56 of each assembly as 50.3 in assembly 33 prevents jamming of the grain and allows for smooth passage and control of the rate of flow of grain passing through each entire column as 42 by the rate of discharge of the auger, as 48, therefor.

In operation of the apparatus 33, as illustrated in FIG. 23, the outward passage of hot air parallel to bin 192-196 and 191-195 from space 45 and heater assembly 59 normal or perpendicular to plane 199 is blocked in

zones

49, 149 and 249, as well as 349, of each column as 42 from reaching the portions of grains as 185, 186 and 187 facing planes as 199 and outward of other grains as 183, 181 and 182, respectively, which are closer to the inner grid or screen 52, except as below described in regard to surfaces 91-94. Similarly, those surface portions of each portion of grain mass outward of particles as 185, 186 and 187 whose surfaces are substantially parallel to the plane 199 have their access to air passing through the mass 80 perpendicular to the inner screen or grid 52 similarly blocked by grains as 185, 186, 187 and 181-184 located between such grains and the grid 52.

As shown in FIG. 22, the outer portion 80.2 of the grain mass 80 in the grain space 54 of column 42 is the portion thereof adjacent to grid 53 about unit 50. When the mass of grain 42.3 moves downward past edges as 125-106 and then passes below edge 106-123 of panel 71 (like edge 105-108 of panel 61 of unit 55 of assembly 50.3) the upper surface 93 of that grain mass is directly exposed to very hot and dry air which passes directly to that upper surface 93 through the grid 52 from space 45. This occurs to all increments of grain in the portion 80.2 during movement of such overall mass of grain 80.2 from its position above 50.3 and units 50.1 and 50.2 of assembly 50 to their position below assembly 50, as shown in FIG. 22. Thereby, the surface of all such grain particles (as 181-187) are exposed to air passing parallel to the plane 199 when the upper surface of each increment of the mass of grain 80.2 is so exposed as at position 193, as shown in FIG. 22; the portions of mass 80.2 are thus exposed to streams of air passing in the direction of a line extending from points 195 to 197, as shown in FIG. 23 as each increment of grain of mass 80.2 passes through a surface as 91 and 93.

Additionally, the inner. portion 80.1 of the grain on each column as 42 of apparatus 33, is the portion of grain mass in grain space 54 of column 42 adjacent to grid 52 above the unit 50, as shown in FIG. 22; when such mass 80.1 passes below the outer edge of panel as 171 (corresponding to edge 106-123 of panel 71 of unit 55 of assembly 50.3) the upper surface 193 of such grain mass is exposed to air passing outwardly through grid 52 during movement of the grain mass 80.1 from the position thereof above unit 150.3 of assembly to a position below unit 150.3 thereby the surfaces parallel to plane 199 of all such grain in mass as 181-187 of FIG. 23 are directly exposed to air passing therethrough in the direction of points 195 to 197 and parallel thereto and are perpendicular to planes 188.

Thereby, according to the apparatus and process of this invention, while the grain mass as 80 of each column as 42 may be regarded as having, above unit 50. one portion 80.1 adjacent grid 52 and another rear portion adjacent grid 53, both portions are exposed to the flow of drying air through the interstitial spaces between contact points thereof along three mutually

perpendicular planes

188, 198 and 199 whereby all substantial surface portions of grain are directly and effectively contacted by the hot drying gas in their passage through the column as 42 of apparatus 33.

The grain moves smoothly along like air contacting surface planes as 91 and 93 and 191 and 291 at an angle, of about 40, which angle is determined by the angle of repose of the mass of grain as 80 as the downward velocity of such mass of grain is so very slow, as controlled by augers as 48.

On movement of the grain downward. through the column as 42 at the particular low speeds for the preferred embodiment and with the dimensions of units as 50.3 the portions of the grain located at different positions at the top surfaces of each turning element, as

shown in FIGS. 12-20, change their position in the grain column, as shown for one, central, portion of the column 42.3 in which portion are located assemblies 50.3, 150.3, 250.3 and the

grain column portions

49, 149 249 therebetween from the numbered positions therefor shown in FIGS. 13 and 14 to the position shown in FIGS. 16 and 15, respectively, on passage through unit 50.3 and thence to the numbered positions thereof shown in FIGS. 17 and 18, respectively. on passage through unit 150.3 and then to the position thereof shown in FIGS. 20 and 19 on passage through unit 250.3. Accordingly, such motion, through each two units in tandem as 50.3 and 150.3 of each assembly as 50 and 150, provide for a change of orientation of the grain particles relative to their vertical axis thereby increase the effectiveness of contact of the air stream passing through grid 52 and the grain mass between

grids

52 and 53 although not as regularly as the surface Contact provided by the change in relative planes of gas movement at

surfaces

93 and 91 provided by the vertically arrayed cooperative units as 50.3 and 150.3 (and others in units 50, and 250). However, the movement effected in these pairs of units as 50.3 and 150.3 are cooperative and additive and accordingly particularly effective to expose all surface of the grains in mass 80 to the air. The same movement and relation is shown for portions 42.3 apply to the other vertical portions of column 42, i.e., the portions 42.1 and 42.2 and, likewise, the corresponding portions of column 42A.

The air flow, as 97, through surface as 93 like flow as 97 in units 150 in like zones (193 in

unit

150 and 97" in unit 250) is far greater than air flow, as 98, through column portions as 49 and like air flow veloci ties through similar full thickness flow through column 42 (through segment as 98' through 149 and 98" through 249 and 349). The flow through cavities as 99 and 99 and 199' above surfaces as 96 and 95 and 196 (below

panel

75 and 65 and 175, respectively) and like zones in other units as 50.3 in the assembly 33 does not provide contact of hottest driest gases with moist cool surfaces as occurs at surfaces as 93; however, the voids as 99 between surfaces as 96 and panel 75 do provide for some increased rate of flow of air or gas streams as 99A and 199A and 299A.

The first turn assembly units 50.1 and 50.2 and 50.3 and units of assembly 50A serve to remove the grain as 80.2 initially adjacent the inner screen or grid 52 and partially dried by gas streams as 98 in its passage from level 13A to the top of assembly 50 from such a lengthy exposure to the hot heating and drying gases from assembly 59 as would carmelize portions of that grain in the column portion 42 of apparatus 33 adjacent grid 52 and also serves to expose at surface 93 surfaces of the grain mass 80.1 not theretofore directly exposed to the hot dry air.

The units of second turn assembly 150 and 150.A corresponding to units 50.1, 50.2, 50.3 of assembly 50 serve not only to remove the grain mass 80.1 from undue lengthy exposure to the hot heating and drying gases as could carmelize that portion of the grain in segment 149 of columns 42 and like portion of column 42A butalso such second turn effectively exposes to the very slow moving gases passing through the columns 42 (and 42A) all surfaces of the grain particles forming portion as 80.2 of the grain mass 80 as above described in regard to actions of

surfaces

91, 93, 191, and 291.

The exposure to heating gas on such downward motion is sufficiently effective that the moisture diffusion which occurs from the interior of the grain particles effectively removes so much of the moisture in the grain particles as to permit such grain particles after such treatment in dryer 33 to be stored in bins as 31A-G without deterioration as occurs from excessive moisture content and consequent biochemical action and heating at localized points at which localized high moisture content would otherwise exist. The danger and harm to even small zones of high moisture content is that the sequence of such a content followed by biochemical action followed by heating further provides that the resultant localized heating at one small initial zone of grain at such high moisture condition causes biochemical action and further heating in the volume of grain adjacent to such one small initial point and Zone. The raised temperature of the larger resulting zone similarly causes sequential heating and quality deterioration in neighboring zones of the grain mass in the bins, as 31A-G; however, by the improved removal of moisture provided by this apparatus and process, such initial developmentof such initial zones is substantially inhibited and substantially prevented.

Such improved exposure of this process results in removal of additional moisture from the grain at low temperature and lowers the frequency of needed recycling of the grain in the bins 31A-31G of the installation 30 to the dryer 33; alternatively phrased, the same dryer 33 with the plurality and sequence of turning assemblies as 50, 150, 250 provided in the columns as 42 and 42A thereof, effectively treats a larger volume of the same grain than would otherwise be treated in such columns with the same heating and

cooling assemblies

58 and 59 or more effectively and efficiently treats the same volume of such grainwith the same heat and air flow input.

The quantitative effect of the flow above and into and through surfaces as 93 and 91 in units as 50 towards and through screen or grid 53 is very substantial; for example, with a particular installation as 30 wherein the apparatus 33 has a space 40 that is 9 feet wide and 60 feet high, with 12 feet long column segments 49 and 149 and 45 feet from top of column 42 to baffle 43 and 12 feet from bottom of space 45 to baffle 43 with center of assembly 250 6 feet below baffle 43 using 3 like units as 50.1, 50.2 and 50.3 to form each unit as 50 (50A, 150A, 250, 250A, etc.) of dimensions as set out in Table II and grids 52 and 53, each being of a screen opening size of A by /8 with 1/64 inch wire and a pressure differential of one inch of water in the zones 40 and 45 over the pressure in zone 46 treating corn grains and measuring air flow rates by the angle of quilting thread in zone 46, an air flow rate of 4 to 6 times the average air flow through segments 49, 149, 249 exists during operation of the apparatus 33 at zones between plates 74 and 68 of units as 50.3 below panels as 71 and also lateral or rightwards of plates as 64 and below the location of panel 61 which corresponds to the lowered thickness of the mass of grain thereat as shown in FIG. 22 and the lowered resistance to air flow through mass near zone surfaces as 93 as above discussed.

Savings in grain treatment cost by the above process have been and are substantial. At the one installation as above described, treating corn wherein

assemblies

58 and 58, without assemblies as 50, 150, 250, 50A,

150A, 150A and 250A, produced 92,000 cubic feet per minute and used 18,000,000 B.T.U. per hour for adequate drying of a throughput of 1,500 bushels per hour and used input temperature of 250F, the same drying result (tested by same moisture test at the discharge of auger 48) was obtained using only 12,000,000 B.T.U. per hour and input gases temperature of l40l50F.

Edges

108 and 109 and 125-426 and ll2-101 and -117 of units as 50.3 extend to and are firmly attached to vertical and horizontal members of column frame 25 and extend between and

contact screens

52 and 53. Edges between points 126l241l8119-10- 7-l04l03102 contact screens 52 while edge between points 109-110-121-120-128-122, 117-116 contact screen 53. Rigid end rectangular end panels TABLE 1 Insert (l) EDGES OF PANELS OF TURNING UNIT 50 Edges Panel No. Top lnner Outer Bottom & 105-108(1.) 63 106-107 105-104 64 104-110 110-121 104-103 103-111(1) & ll l-l2l(o) 65 102-103 111-112 102-103 111-112 66 120-121 120-121 111-113 111-113 67 102(p) 102-112 102-101 101-112 68 107-128 107-119 128-120 109-113(0) & 120-1 13(i) 71 106-128 106-123 128-122 123-122 72 125-128 106-123(c) & 125-123(1.) 73 125-126 126-124 123-125 124-123 74 124-122 118-114 122-117 117-114(1) & 114-118(0) 75 118-119 118-114 119-113 114-113 76 116-117 116-117 115-114 115-114 77 116(p) 116-127 116-115 115-127 LEGEND: (p)Point (c)Central (L )Lateral (i)1nner ()0ulcr TABLE 11 Insert (2) MEASUREMENTS OF UNlT 50.3 From To Distance Point 108 Point 109 Point 106 Point 107 6 inches Point 106 Point 128 Point 126 Point 125 Edge 104-110 Point 111 11 inches Edge 122-124 Point 114 Edge 104-110 Point 103 inches Edge 122-124 Point 118 Edge 107-128 Point 1 13 22 inches Point 125 Point 109 34% inches Points 106, 107, 108. 109. 125 126 and 128 are all on same horizontal plane.

as 69.1 and 69.2 may be screens as 52 and 53 or imperforate panels as 68 and are located between each unit as 50.3 and units as 50.1 and 50.2 adjacent thereto and extend as a rectangular shape from screen 52 to screen 53 and from level of edges as 108-109 to level of 112-101 and from level of edges 126-125 to level of 115-127 and are there firmly held in place by and attached to frame 25.

The rate of discharge control from each column as 42 is controlled by an auger as 48 but is also adjusted by the adjustable gate 54.5 held by a bracket 54.4 which is adjusted by a screw as 54.2 by turning its handle 54.3, the screw being supported on a bracket as 54.1 of the frame 25 as shown diagrammatically in FIG. 22.

1 claim:

1. ln a process of drying grain in a column drier including the steps of passing a mass of grain to be dried downward through a first vertically extending column of rectangular section, while passing hot air through one, preferred vertically extending air inlet surface of said column into said grain mass through said grain and outward of a perforated vertically extending air outlet surface, the improvements which comprise:

a. passing a first portion of said grain theretofore adjacent said outlet screen downwardly along a surface at an angle greater than the angle of repose of said grain and then toward said inlet screen while supporting and upwardly exposing a surface of said grain mass at its angle of repose directly to the hot air stream and directly passing said hot air from said inlet screen to said upwardly exposed grain surface through said grain and outward of said out let screen, and then b. moving the said first portion of grain mass downward of the column along the inlet screen while exposing a vertical surface of said mass to said hot air, and then passing a second portion of said grain theretofore adjacent said outlet screen along a surface at an angle greater than the angle of repose of said grain towards said inlet screen while supporting and upwardly exposing a surface of said grain mass at its angle of repose directly to the hot air stream and directly passing hot air through and outward of said inlet screen to said upwardly exposed grain surface through said grain and outward of said outlet screen, while (1. moving the grain mass theretofore adjacent to the inlet screen toward the outlet screen and then vertically downward in contact therewith and moving said second portion of grain mass downward of the column along the inlet screen while exposing a vertical surface of said mass to said hot air.

2. Process as in claim 1 wherein allof the plurality of portions initially adjacent the outlet screen are moved as is said first portion and all portions of said grain mass originally adjacent the inlet screen move through said column as does said second portion.

3. Process as in claim 2 wherein the grain is subsequently passed through a cooling section where another similar reversal of the two separate portions of the grain mass is made and direct exposure of sloped grain surface is similarly provided to a mass of cooling air passed through the inlet screen.

Claims

1. In a process of drying grain in a column drier including the steps of passing a mass of grain to be dried downward through a first vertically extending column of rectangular section, while passing hot air through one, preferred vertically extending air inlet surface of said column into said grain mass through said grain and outward of a perforated vertically extending air outlet surface, the improvements which comprise: a. passing a first portion of said grain theretofore adjacent said outlet screen downwardly along a surface at an angle greater than the angle of repose of said grain and then toward said inlet screen while supporting and upwardly exposing a surface of said grain mass at its angle of repose directly to the hot air stream and directly passing said hot air from said inlet screen to said upwardly exposed grain surface through said grain and outward of said outlet screen, and then b. moving the said first portion of grain mass downward of the column along the inlet screen while exposing a vertical surface of said mass to said hot air, and then c. passing a second portion of said grain theretofore adjacent said outlet screen along a surface at an angle greater than the angle of repose of said grain towards said inlet screen while supporting and upwardly exposing a surface of said grain mass at its angle of repose directly to the hot air stream and directly passing hot air through and outward of said inlet screen to said upwardly exposed grain surface through said grain and outward of said outlet screen, while d. moving the grain mass theretofore adjacent to the inlet screen toward the outlet screen and then vertically downward in contact therewith and moving said second portion of grain mass downward of the column along the inlet screen while exposing a vertical surface of said mass to said hot air.

2. Process as in claim 1 wherein all of the plurality of portions initially adjacent the outlet screen are moved as is said first portion and all portions of said grain mass originally adjacent the inlet screen move through said column as does said second portion.