RU2802314C2 - Device, vapour-permeable base component and method for drying pool grain material - Google Patents

Abstract

FIELD: drying technology.

SUBSTANCE: device for drying bulk granular material contains an inlet chamber for receiving wet bulk granular material and an outlet chamber for discharging dry bulk granular material. The inlet chamber contains a vapour-permeable base divided into a plurality of subsections, including the first subsection and the second subsection. Each subsection defines the first and the second radial centre line. The first subsection and the second subsection each have at least one louvered flat section containing a plurality of louvered dampers located in the first and second specific directions, respectively, to direct superheated steam in the first and the second discharge directions to the said lower inner cylindrical wall. The specific direction of the shutters of the first subsection defines the first angle relative to the first radial centre line, and the specific direction of the said shutters of the said second subsection defines the second angle relative to the said second radial centre line, while the said first angle and/or the said second angle differ from 0 degrees.

EFFECT: improved mixing of particles already partially dried in the first drying chamber and new particles for uniform distribution of the granular material in the first drying chamber, which will increase drying efficiency.

10 cl, 7 dwg

Description

BACKGROUND OF THE INVENTION

A known method of drying wet bulk granular material by providing contact of the granular material with superheated steam. This ensures the evaporation of the liquid contained in the material.

Early disclosure of the above steam drying technologies includes EP 0 058 651 A1 disclosing a method for preparing cattle feed from various agricultural products such as sugar beet pulp, citrus pulp and various fermentation products.

Another document EP 0 153 704 A2 discloses a method for removing liquid from a solid particulate material, in which the material is passed through a series of interconnected cells and superheated steam is introduced into said cells at their lower ends to provide a swirling motion when the particles to be dried are lifted from the cells into the common movement area and into the dispensing cell without steam supply.

Prior art document WO 92/01200 discloses a device for drying wet particulate material having a non-uniform particle size by means of superheated steam. The device contains a cylindrical container containing a plurality of parallel, essentially vertical drying chambers arranged in the form of a ring. The preferred implementation includes fifteen drying chambers connected in series and a dispensing chamber located between the first and last drying chamber.

In the first drying chamber after the inlet, the particulate material will have a high moisture content, and the particulate material in the last drying chamber will have a low moisture content. The drying chambers are configured to move the flow of superheated steam to improve the contact between the steam and the granular material, and ensure that the granular material passes through all the cells before drying. In particular, wet particles are generally heavier than dry particles and therefore require higher flow and steam rates.

The Applicant has found that wet granular material and in particular large and heavy particles tend to accumulate in the first drying chamber. Particulate material remaining in the first drying chamber for an extended period of time can potentially clog the first drying chamber and reduce the swirling intensity of the superheated steam flow.

Therefore, it is an object in accordance with the present invention to provide improved techniques for preventing material accumulation in the first drying chamber by providing one or more vortex movements in different directions in the first drying chamber.

In particular, the object of the invention is to provide improved mixing of the particles already partially dried in the first drying chamber and the new particles, so that the swirling movements at increased speed allow a more uniform distribution of the granular material in the first drying chamber, which will lead to more efficient drying.

SUMMARY OF THE INVENTION

The above objects, evident from the following detailed description, according to the first aspect of the present invention are achieved by an apparatus for drying wet bulk granular materials, the apparatus comprising:

a container configured to maintain superheated steam at a pressure equal to or greater than the ambient pressure surrounding the container, the container defines a lower cylindrical part having a lower inner cylindrical wall and defining a first cross-sectional area perpendicular to the length of the lower cylindrical part, and an upper cylindrical part, having an upper cylindrical inner wall and defining a second cross-sectional region perpendicular to the length of the upper cylindrical part,

an inner cylindrical part located centrally inside the upper cylindrical part and the lower cylindrical part of the container to form the first fluid channel from the upper cylindrical part to the lower cylindrical part inside the inner cylindrical part and the second fluid channel from the lower cylindrical part to the upper cylindrical part behind outside the inner cylindrical part,

a plurality of dividing walls extending in the radial direction inside the lower cylindrical part between the lower cylindrical part and the inner cylindrical part and defining in the lower cylindrical part an inlet chamber, an outlet chamber and a plurality of intermediate chambers located between the inlet chamber and the outlet chamber in the circumferential direction, while the inlet the chamber contains an inlet for receiving wet bulk granular material, the outlet chamber contains an outlet for discharging dry bulk granular material, each of the inlet chamber and the intermediate chamber defines a vapor-permeable base,

a heat exchanger assembly located inside the inner cylindrical part for heating superheated steam,

an impeller for generating a superheated steam flow within the vessel and along the first fluid passage from the upper cylindrical portion through a heat exchanger within the inner cylindrical portion to the lower cylindrical portion and generally along the second fluid passage from the lower cylindrical portion to the upper cylindrical portion beyond limits of the inner cylindrical part,

wherein the vapor-permeable base of at least the inlet chamber is divided into a plurality of sub-sections, including the first sub-section and the second sub-section defining the first and second radial center lines, respectively,

wherein each of the first subsection and the second subsection has at least one louvered flat section, containing a plurality of louvered dampers located in the first and second specific direction, respectively, for directing superheated steam in the first and second discharge directions, respectively, to the lower internal cylindrical wall

moreover, the specific direction of the shutters of the first subsection determines the first angle relative to the first radial center line,

wherein the particular direction of the louvres of the second subsection defines a second angle relative to the second radial center line, and

the first angle and/or the second angle is different from 0 degrees.

The vessel is usually made of metal that can withstand superheated steam temperatures in excess of 100°C and pressures in excess of ambient atmospheric pressure. Typical pressures range from ambient atmospheric pressure up to a maximum pressure of 3 bar. The container contains a lower cylindrical part and an upper cylindrical part, which form part of the upper compartment of the container, and an intermediate conical part between the lower and upper cylinder.

The source of steam supply may be a boiler or a steam outlet in another pressurized steam system, such as a turbine outlet.

The first fluid passage within the inner cylindrical portion and the second fluid passage between the outer containment of the vessel and the inner cylindrical portion determine the recirculation of the superheated steam. The flow of superheated steam is provided by an impeller located in the lower cylindrical part under the vapor-permeable base and/or between the inner cylindrical part and the vapor-permeable base of the lower cylindrical part, to provide high pressure under the vapor-permeable base, which in turn provides a fluidized bed and a recirculating flow of superheated pair. The inner cylindrical part contains a heat exchanger that keeps the recirculating steam superheated to prevent any condensation inside the vessel.

Dehumidification is carried out by contacting superheated steam with wet particulate material and transferring some of its heat to the wet particles. The moisture content of the wet particulate material will evaporate and the steam becomes part of the circulating steam. The thermal energy required for evaporation and therefore taken from the superheated steam is replenished at the heat exchanger to prevent the superheated steam from condensing into a liquid inside the vessel. Any excess steam can be removed from the dryer through the top of the tank, for example through a valve. The container also contains means for providing a peripheral flow component to slow down the movement of the particulate material in the circumferential direction from the inlet to the outlet.

Dividing walls ensure the division of the lower cylindrical part into a plurality of chambers. The first chamber is an inlet chamber connected to a closed screw conveyor or the like for introducing wet particulate material into the inlet chamber. The discharge chamber also contains a closed screw conveyor or the like for dispensing dry granular material. The intermediate chambers are located between the inlet chamber and the outlet chamber. The dividing walls contain openings to enable movement of the granular material from the inlet chamber to the outlet chamber through the intermediate chambers. The inlet chamber and intermediate chambers receive superheated steam from the vapor-permeable base and thus constitute the drying chambers.

Inside the dryers, a fluidized bed and flow is provided which keeps most of the particulate material in the lower cylindrical portion and enhances the contact between the superheated steam and the particulate material.

The outlet chamber preferably does not have a vapor-permeable base to allow the particulate material to settle before being dispensed. The number of cameras determines (influences) the standard deviation of the retention time for the distribution. Increasing the number of chambers reduces the standard deviation of the retention time of the granular material.

The granular material entering the first drying chamber, i. e. inlet chamber is wet and contains a significant amount of moisture, and thus is usually heavy and clogs the chamber. These heavy particles require high flow rates. This results in less lift in the fluidized bed, less swirl in the flow, and less distribution of particulate material, which leads to accumulation of wet particulate material in some parts of the inlet chamber. The particulate material entering the last drying chamber upstream of the outlet chamber, from which the now dry particulate material is discharged, is essentially dry.

Thus, in order to provide a well-formed vortex flow of superheated steam inside the inlet chamber, the vapor-permeable base is divided into a plurality of subsections, and several of these subsections are equipped with a louvered flat section with a plurality of louvered dampers to direct the flow of superheated steam towards the lower inner cylindrical wall.

The study conducted by the Applicant has proved that the arrangement of subsections having louvered flat areas defining the first and second injection directions, which are not equal to zero, forms one or more swirl motions of superheated steam in different directions, which increases the flow and speed of swirl motions, as well as improves the drying process. This also results in improved mixing of fresh and semi-dried particles.

The inlet chamber is made with many sub-sections, but not all sub-sections can be made with louvered dampers, i.e. the first subsection closest to the inlet may be provided with or without louvres, and the last subsection, or any plurality of any intermediate subsections, may be made without louvres.

According to another embodiment of the first aspect, the first angle is numerically greater than the second angle by 7.5 to 90 degrees, preferably numerically greater than the second angle by 10 to 60 degrees.

In accordance with another embodiment of the first aspect, the vapor-permeable base of at least the inlet chamber contains a third subsection located between the first and second subsections, and the intermediate third subsection contains at least one louvered flat section having a plurality of louvered dampers located in a third specific direction for direction of the superheated steam in the discharge direction towards the lower inner cylindrical wall, wherein the third particular direction of the louvres defines a third angle with respect to the corresponding third radial center line, wherein the third angle differs from 0 and ranges from 0 to 90 degrees.

Louver dampers of the third subsection, located at an angle relative to the corresponding radial center line, enhance the vortex motion of the superheated steam flow. The third angle may be substantially equal to or greater than the first angle in numerical value. In another implementation, the third angle may be substantially equal to or greater than the first angle in numerical value.

In accordance with another embodiment of the first aspect, at least the inlet chamber comprises a transitional flat section located as a transitional section between the vapor-permeable base and the inner cylindrical part. The transition flat section contains a louvered flat section for directing the flow of superheated steam in the discharge direction to the lower inner cylindrical wall, while the injection direction determines the angle in the vertical direction, and, compared with the horizontal plane, the angle is from -80 to 80 degrees, preferably from -60 to 60 degrees, more preferably -40 to 40 degrees, most preferably -40 to 0 degrees.

During the drying and swirling of the bulk particulate material within the chambers, most of the bulk particulate material will swirl downward on the inner cylindrical portion, along the vapor-permeable base toward the lower inner cylindrical wall, and upward along the lower inner cylindrical wall. The louvres in the transitional flat section provide an outward pumping effect from the inner cylindrical portion, which enhances circulation and speeds up the swirling motions.

The direction of injection of the louvres in the transition flat section is directed towards the lower inner cylindrical wall and inclined in the circumferential direction, essentially similar to the louvres of the vapor-permeable base of the corresponding subsection. Alternatively, the louvers of the transition flat portion may direct the flow of superheated steam towards the lower inner cylindrical wall in a discharge direction substantially identical to the corresponding radial center line.

According to another embodiment of the first aspect, the sub-sections comprise a plurality of louvered flat areas, said particular direction of the two or more said louvered flat areas defines a different angle relative to said radial center line, respectively.

Each sub-section contains a plurality of louvered flat sections, each of which defines the angle between the radial center line, respectively, and a specific direction of the louvered flat sections, while the angle of the louvered flat sections, made facing towards the lower cylindrical part, is preferably larger compared to the angle of the louvered flat sections. flat sections made facing towards the inner cylindrical part.

In accordance with another embodiment of the first aspect, the vapor-permeable base contains a plurality of holes for directing said superheated steam in a substantially vertical discharge direction, and the open area of the inlet chamber louvres forms an area from 10% to 90% of the total open area of all openings and louvres of the vapor-permeable base. inlet chamber, preferably 20% to 60%, more preferably 30% to 50%, for example about 40% to 50%.

The holes may be arranged in a regular pattern across the surface of the base, or may be arranged in groups. The combination of louvres and openings enhances the swirling motion of the superheated steam flow.

According to the second aspect of the present invention, the above objects and advantages are achieved by:

vapor-permeable base component for a device for drying bulk granular material, wherein the vapor-permeable base component contains at least one subsection defining a radial center line, the subsection has a louvered flat section having a plurality of louvered dampers facing in a specific direction to direct superheated steam in the discharge direction towards the lower inner cylindrical wall, a particular direction of the louvres forms an angle with respect to the first radial center line, the angle being in the range of 7.5 degrees to 90 degrees in numerical value, preferably 10 degrees to 75 degrees, preferably 11.5 up to 60 degrees.

Obviously, the vapor-permeable base according to the second aspect can be used with the devices according to the first aspect.

According to the third aspect of the present invention, the above objects and advantages are achieved by:

method of drying bulk granular materials by providing a device that contains:

a container defining a lower cylindrical portion having a lower inner cylindrical wall and defining a first cross-sectional region perpendicular to the length of the lower cylindrical portion and an upper cylindrical portion defining a second cross-sectional region perpendicular to the length of the upper cylindrical portion;

an inner cylindrical part located centrally inside the upper cylindrical part and the lower cylindrical part of the container, with the formation of the first fluid channel from the upper cylindrical part to the lower cylindrical part inside the inner cylindrical part and the second fluid channel from the lower cylindrical part to the upper cylindrical part outside the inner cylindrical part,

a plurality of dividing walls extending in the radial direction inside the lower cylindrical part between the lower cylindrical part and the inner cylindrical part and defining in the lower cylindrical part an inlet chamber, an outlet chamber and a plurality of intermediate chambers located between the inlet chamber and the outlet chamber in the circumferential direction, while the inlet the chamber contains an inlet,

the outlet chamber contains an outlet, each of the inlet chamber and intermediate chambers defines a vapor-permeable base, the outlet chamber preferably defines a vapor-tight base, the vapor-permeable base of said inlet chamber is configured to receive superheated steam from said impeller,

the vapor-permeable base is configured to direct the flow of superheated steam in a plurality of directions to the lower inner cylindrical wall and in directions different from the radial direction of the vapor-permeable base;

a heat exchanger located inside said inner cylindrical part, and an impeller,

the method includes the steps in which:

• maintain superheated steam inside the vessel at a pressure that is equal to or greater than the pressure of the medium surrounding the vessel,

• receive wet bulk granular material at the indicated inlet,

• heat the steam inside the specified heat exchanger,

• superheated steam flow is generated along the first fluid channel from the upper cylindrical part through the heat exchanger inside the inner cylindrical part to the lower cylindrical part, and through the vapor-permeable base, the superheated steam flow is directed in a plurality of directions other than the radial direction towards the lower inner cylindrical wall, and generally along the second fluid passage from the lower cylindrical part to the upper cylindrical part outside the inner cylindrical part, by using the impeller, thereby increasing the speed and swirling motion of the superheated steam, and

• release dry bulk granular material at the outlet.

In accordance with another embodiment of the third aspect, in which, through the vapor-permeable base, the flow of superheated steam is directed in the first direction towards the lower inner cylindrical wall, defining the first angle relative to the radial direction, and in the second direction towards the lower inner cylindrical wall, defining the second angle relative to the radial direction, with the first angle different from the second angle.

The study carried out by the applicant has shown that by using the above method of drying bulk granular materials with superheated steam, by providing one or more vortex movements in different directions inside the first drying chamber, the accumulation of material in the first drying chamber is prevented and mixing of particles already half dried in the first is carried out. drying chamber, and new particles. The vortex movements in different directions allow the grain material to be more evenly distributed in the first drying chamber, resulting in more efficient drying.

BRIEF DESCRIPTION OF THE DRAWINGS

In FIG. 1A shows a side sectional view of a device for drying bulk granular material, in particular for drying beet pulp.

In FIG. 1B shows an exploded sectional view of a vapor-permeable base.

In FIG. 2 shows a perspective view of the lower cylindrical portion of the device.

In FIG. 3A-3C are top sectional views of various embodiments of the lower cylindrical portion of the device.

In FIG. 4 shows a top view in section of the lower cylindrical part of the device.

In FIG. 5A shows an internal perspective view of the bottom of the inlet chamber.

In FIG. 5B shows an exploded view of the vapor permeable base.

In FIG. 5C shows an exploded view of the transitional flat area.

In FIG. 5D is a sectional view of the louvered flat portion along line AA.

In FIG. 5E is a sectional view of the louvered transition flat portion along line BB.

In FIG. 6A is a sectional perspective view of the upper surface side of the louvre flat portion.

In FIG. 6B is a perspective view of the bottom surface side of the louvered flat portion.

In FIG. 7 shows a perspective view of the interior of a bulk particulate dryer.

IMPLEMENTATION OF THE INVENTION

In FIG. 1A shows a side sectional view of a device 10 for drying bulk granular materials, in particular for drying beet pulp. The device 10 includes a container 12 having a lower cylindrical part 14, an intermediate conical part 16 and an upper cylindrical part 18. The container can be made without a conical part, so the lower (14) and upper cylindrical part (18) have the same cross-sectional area.

The container 12 is closed by a top 20 and a base 22. The container 12 further comprises an inner cylindrical portion 24 extending within the container between the upper cylindrical portion 18 and the lower cylindrical portion 14. The inner cylindrical portion 24 comprises a heat exchanger (not shown) and defines a first fluid passage. from the upper cylindrical part 18 to the specified lower cylindrical part 14 inside the inner cylindrical part 24 and the second fluid channel from the lower cylindrical part 14 to the upper cylindrical part 18 outside the inner cylindrical part, as shown by arrows.

The container 12 further comprises an inlet 26, which may include a screw conveyor for introducing wet particulate material into the lower cylindrical part 14 of the container 12, as shown by the arrow, and an outlet 28, which may also contain a screw conveyor for withdrawing dry particulate material from the lower cylindrical part. 14 containers 12, as shown by the arrow. The inlet 26 is located above the outlet 28 and offset relative to it in the circumferential direction. An engine 30 is located below the vessel 12 to drive an impeller 32 located in the lower cylindrical portion 14 under the inner cylindrical portion 24. The impeller 32 generates a superheated steam flow along the above fluid channels. The vapor-permeable base 34 is located above the impeller 32. The vapor-permeable base 34 includes a plurality of holes 50 for directing superheated steam in a substantially vertical direction and a plurality of louvered flat sections 62'-62'''' having a plurality of louvered dampers 64 for directing superheated steam along towards the lower inner cylindrical wall.

A plurality of dividing walls 36 extend radially between the lower cylindrical part 14 and the inner cylindrical part 24 and divide the space between the lower cylindrical part 14 and the inner cylindrical part 24 into a plurality of chambers 38. The chamber located on the inlet 26 is designated as the inlet chamber 38' , and the chamber located on the outlet 28 is designated as the outlet chamber 38''. Usually the inlet chamber 38' and the outlet chamber 38'' are located next to each other, but the possibility of the granular material passing directly from the inlet chamber 38' to the outlet chamber 38'' without passing through the intermediate chambers 38 must be excluded. Wet particulate material is received in the inlet chamber 38' on a fluidized bed formed by the flow of superheated steam over the vapor-permeable base 34. The dividing walls 36 include vortex blades 40 to provide a peripheral vortex to move the particulate material from the inlet chamber 38' to the outlet chamber 38'' through intermediate chamber 38 as shown by the arrows. The outlet chamber 38'' preferably has an impermeable base which allows the dried particulate material to exit through the outlet 28 as indicated by the arrow.

The upper cylindrical part 18 of the container 12 contains guide vanes 42 for generating a cyclone field in the upper cylindrical part 18. The guide vanes 42 provide a vortex movement of the superheated steam flow corresponding to the above peripheral vortex and expel any particles that have been lifted from the lower cylindrical part 14 through the intermediate cone-shaped part 16 into the upper cylindrical part 18, outward. The particles pushed outward will be collected in the cyclone 44 and returned to the lower cylindrical part 14 as indicated by the arrows. The superheated steam will be introduced into the inner barrel 24 and reheated by the heat exchanger assembly before returning to the impeller 32. A small portion of the superheated steam will leave the vessel 12 through a centrally located steam outlet 46. The superheated steam exiting the vessel 12 is then cooled by means of a heat exchanger.

Drying of the wet particulate material is carried out on a fluidized bed above the vapor-permeable base of the inlet chamber 38' and intermediate chambers 38. Each chamber 38 may include additional vanes or the like to provide a vortex flow in the radial direction of the chamber 38. The vortex flow will increase the distribution of the particulate material within the chambers 38 and thus increasing the contact between the superheated steam and the particulate material, in turn increasing the evaporation of the fluid from the particulate material and improving the drying process.

In FIG. 1B shows an exploded view in section of the vapor permeable base 34. The exploded view shows a louvered flat portion 62'-62'''' having louvers 64. The figure shows the molded louver material facing the impeller and the injection direction towards the second port for fluid and at an angle in the vertical direction from 0 to 90 degrees relative to the horizontal plane, preferably less than 60 degrees.

In FIG. 2 shows a perspective view of the lower cylindrical portion 14 of the device 10. The inlet chamber 38' is larger than the intermediate chambers 38 and the outlet chamber 38'' to allow more superheated steam to enter the inlet chamber 38' compared to the intermediate chambers 38. Thus, heavy moisture-containing particulate material entering the inlet chamber 38' can be distributed over a larger area, reducing flow resistance and thus preventing clogging and improving drainage.

In FIG. 3A-3C show a top sectional view of various embodiments of the lower cylindrical portion 14 of the device 10.

In FIG. 3A shows an inlet chamber 38' having two subsections, a first subsection 52' and a second subsection 52''.

In FIG. 3B shows an inlet chamber 38' having three subsections, a first subsection 52', a second subsection 52'' and a third subsection 52'''.

In FIG. 3C shows an embodiment in which the inlet chamber 38' has four subsections, a first subsection 52', a second subsection 52'', a third subsection 52''', and a fourth subsection 52''''. In another embodiment (not shown), the inlet chamber may be configured with a different number of intermediate subsections, such as three, four or five subsections, or any greater number of intermediate subsections.

The radial dividing walls 36 define the circular shape of the chamber sector 38, 38', 38''. The particulate material can move in a clockwise direction from the inlet chamber 38' to the outlet chamber 38'' through all intermediate chambers 38 by passing over the dividing walls 36 or through openings 48 which may be formed in the dividing walls 36 if desired.

The subsections 52'-52''' of the inlet chamber 38', in addition to the louvres 64, also contain openings 50 (as shown in the second subsection 52'' in FIG. 3A) for directing a portion of the superheated steam through the vapor permeable base 34 and in a substantially vertical direction.

In FIG. 3A each of the first sub-section 52' and the second sub-section 52'' is depicted as containing a louvered flat section 62'-62'' with a plurality of louvered dampers 64 for directing a portion of the superheated steam towards the lower inner cylindrical wall of the lower cylindrical part 14.

The first sub-section 52' is shown comprising a first louvered flat section 62' in a particular direction 68' such that the injection direction of the first louvered flat section 62' and the first radial center line 66' of the first sub-section 52' define a first angle (α ₁ ) which in the illustrated embodiment is approximately 60 degrees. The second subsection 52'' is shown having a second louvered flat portion 62'' positioned in a specific direction 68'' such that the injection direction of the second louvered flat portion 62'' of the second subsection 52'' and the second radial center line 66'' define the second angle (α ₂ ). The direction of injection of the louvres in the second subsection 52'' is substantially equal to the second radial center line 66'' of the second subsection 52'', and the second angle (α ₂ ) is therefore substantially equal to zero. In an alternative implementation (not shown), the direction of injection of the louvres in the second subsection 52'' may differ from the second radial center line 66'' of the second subsection 52'', and the second angle (α ₂ ) thus has a non-zero numerical value. The first angle in the depicted embodiment is non-zero, and the direction of injection of the first louver flat section 62' is towards the outlet. However, in an alternative implementation, the direction of injection of the first louvered flat portion 62' may be directed at an angle substantially equal to zero, or at an angle other than zero and towards the inlet (26).

In FIG. 3B, the first and second louvred flat portions 62', 62'' of the first and second sub-sections 52', 52'' are arranged in a manner similar to that described with respect to FIG. 3A. The third subsection 52''' is shown as having a third louvered flat portion 62''' disposed towards the third specific direction such that the discharge direction and the third radial center line 66''' of the third subsection 52''' define a third angle (α ₃ ) . In the illustrated embodiment, the third angle (α ₃ ) is substantially numerically equal to the second angle (α ₂ ). In an alternative implementation, the direction of injection of the louvres in the third subsection 52''' may be different from the third radial center line 66''', and thus the third angle (α ₃ ) is non-zero.

In FIG. 3C shows an embodiment of an inlet chamber 38' in which the injection direction of the first subsection 52' is similar to the embodiments shown in FIG. 3A and 3B. The embodiment in FIG. 3C shows the second, third, and fourth sub-sections 52''-52'''', each having louvered flats 62''-62'''' arranged in specific directions 68''-68'''' in this way that the direction of injection of each louvered flat section 62''-62'''', as well as the second, third and fourth radial center lines 66''-66'''' of the corresponding subsection define the second angle (α ₂ ), the third angle ( α ₃ ) and the fourth corner (α ₄ ). The second angle (α ₂ ) is shown to be substantially equal to the first angle. The third angle (α ₃ ) is depicted as being non-zero and approximately -20 degrees, and extending towards the inlet (26). The fourth corner (α ₄ ) is shown to be substantially equal to the corresponding radial center line.

In FIG. 4 shows a top sectional view of the lower cylindrical portion 14 of the device 10. The device is shown having an inlet chamber 38', an outlet chamber 38'' and 19 intermediate chambers 38. However, the device can be made with any number of intermediate chambers from 6 to 40, for example from 10 up to 25, for example from 12 to 20. In each of the first subsection 52' and the third subsection 52''', the vapor-permeable base 34 contains more than one louvered flat area 62', 62'''. In the first subsection 52', the base 34 contains four louvered flat sections 62', and in the third subsection 52''', the base 34 contains two louvered flat sections 62'''. Each of the other subsections of the inlet chamber 38' is shown as having one louvered flat area. The vapor-permeable base 34 of each of the subsections 52'-52'''' of the inlet chamber can be made with a different number of louvered flat sections. It is shown that between the vapor-permeable base 34 and the inner cylindrical part 24, the device 10 has transitional flat sections 80'-80'''', having louvered dampers and located in the transitional area between the vapor-permeable base 34 and the inner cylindrical part 24.

In FIG. 5A shows an internal perspective view of the bottom of the inlet chamber 38'. The figure shows an inlet chamber 38' similar to the inlet chamber 38' shown in FIG. 4 and the vapor permeable base 34 is provided with a plurality of louvre flats 62'-62'''' as described in connection with FIG. 4.

Each subsection 52'-52'''' of the inlet chamber 38' is provided with a transitional flat portion 80'-80'''' at an angle relative to the base 34 and the inner cylindrical portion 24. Each of the transitional flat portions 80'-80''' ' has a transitional louvered flat section 82'-82'''' with a plurality of louvered dampers 64 for directing the flow of superheated steam from the transitional flat sections 80'-80'''' and to the lower cylindrical part 14. The direction of injection of the transitional louvered flat sections 80 '-80'''' is directed away from the inner cylindrical portion 24 and inclined in a circumferential direction, which may be substantially similar to the louvres of the base 34 of each respective subsection. In an alternative implementation, the direction of injection of the transition louvre flat sections 82'-82'''' is directed away from the inner and cylindrical part 24 and inclined in a circumferential direction different from the louvres of the base 34 of each respective subsection. Openings 50 are shown in the vapor-permeable base 34 and the transition flats.

In FIG. 5B-5C show an exploded view of louvre flats 62''', 82''', shown with a plurality of louvres 64 arranged in ordered rows. However, any other number of louvers may be provided, which may also be arranged in an offset configuration. The above applies to all 62'-62'''' and 82'-82'''' louvre flats. As shown in FIG. 5D, the injection direction also defines an angle relative to the vertical direction. The angle is from 0 to 90 degrees and preferably less than 60 degrees.

In FIG. 5E is a sectional view of the transition louver flat 82''' along line BB and shows that the stamped flat material of each louver 64 is located on the underside of the transition louver flat 82''' and therefore faces the impeller 32 (not shown in Fig. 5A).

In FIG. 6A is a perspective view of the top surface side of the louvre flats 62'-62''''.

In FIG. 6B is a perspective view of the bottom surface side of the louvre flats 62'-62''''.

In FIG. 7 shows a perspective view of the inside of the device 10. The device 10 is shown without the inlet 26, the lower cylindrical part 14, the upper cylindrical part 18 and the upper part of the inner circular part having guide vanes 42. The device 10 has a plurality of dividing walls 36 separating the lower cylindrical part into a plurality of chambers 38, 38', 38'', with the inlet chamber 38' adjacent to the outlet chamber 38''. The possibility of direct movement of bulk granular material from the inlet chamber 38' to the outlet chamber 38'' without passing through the intermediate chambers 38 is excluded by means of a wall (not shown) passing between the inner cylindrical part 24 and the lower cylindrical part 14.

The outlet chamber 38'' preferably does not contain a vapor-permeable base 34, which allows the bulk granular material to be removed from the device 10 through the outlet 28.

The inlet chamber 38' contains four sub-sections 52'-52'''' arranged as described with respect to FIG. 4 and 5A and is shown without holes 50, which are not excluded from the disclosure. The larger inlet chamber 38' is apparent compared to the intermediate chambers 38 and the outlet chamber 38'', with the larger inlet chamber enhancing the drying process of the bulk granular material.

Although the present invention has been described with reference to several advantageous embodiments, among which one is the presently preferred embodiment, one skilled in the art will appreciate that steam drying itself can be implemented in a variety of different ways, which include technical features, inter alia, steam dryers known from the publications referred to in the introduction of this description. Therefore, any such modifications or use of the ideas of the present invention in combination with known steam drying should be considered part of the present invention and be considered included in the scope of protection defined in the appended paragraphs.

REFERENCE POSITIONS

10. Device for drying bulk granular material

12. Capacity

14. Lower cylindrical part

16. Intermediate cone

18. Upper cylindrical part

20. Top

22. Foundation

24. Inner cylindrical part

24'. Upper inner cylindrical part

26. Inlet

28. Outlet

30. Engine

32. Impeller

34. Vapor-permeable base

36. Dividing walls

38. Intermediate chambers

38'. inlet chamber

38''. outlet chamber

40. Vortex blades

42. Guide vanes

44. Cyclone

46. Steam vent

48. Hole

50. Holes

52'. First subsection

52''. Second subsection

52'''. Third subsection

52''''. Fourth subsection

62'. First louvered flat area

62''. Second louvered flat area

62'''. Third louvered flat area

62''''. Fourth louvered flat area

64. Louvre damper

66'. First radial center line

66''. Second radial center line

66'''. Third radial center line

66''''. Fourth radial center line

68'. First specific direction

68''. Second specific direction

68'''. Third specific direction

68''''. Fourth specific direction

80'. First transitional flat area

80''. Second transitional flat area

80'''. Third transitional flat area

80''''. Fourth transitional flat area

82'. First transitional louvered flat section

82''. The second transitional louvered flat area

82'''. Third transitional louvered flat section

82''''. Fourth transitional louvered flat section

α ₁ . First corner

α ₂ . Second corner

α ₃ . third corner

α ₃ . fourth corner

Claims (34)

1. Device for drying bulk granular material, containing: a vessel configured to maintain superheated steam at a pressure equal to or greater than the ambient pressure surrounding said vessel, wherein said vessel defines a lower cylindrical portion having a lower inner cylindrical wall and defining a first cross-sectional region perpendicular to the length of the lower cylindrical portion and an upper a cylindrical part having an upper cylindrical inner wall and defining a second cross-sectional region perpendicular to the length of the upper cylindrical part, an inner cylindrical part located centrally inside said upper cylindrical part and said lower cylindrical part of said container to form a first fluid channel from said upper cylindrical part to said lower cylindrical part inside said inner cylindrical part and a second fluid channel from said lower cylindrical part to the specified upper cylindrical part outside the specified inner cylindrical part, a plurality of dividing walls extending in the radial direction inside said lower cylindrical part between said lower cylindrical part and said inner cylindrical part and defining in said lower cylindrical part an inlet chamber, an outlet chamber and a plurality of intermediate chambers located between said inlet chamber and said outlet chamber in circumferential direction, wherein said inlet chamber contains an inlet for receiving wet bulk granular material, said outlet chamber contains an outlet for discharging dry bulk granular material, each of said inlet chamber and said intermediate chambers defines a vapor-permeable base, a heat exchanger assembly located inside said inner cylindrical part for heating said superheated steam, an impeller for generating a superheated steam flow within said vessel and along said first fluid passage from said upper cylindrical portion through said heat exchanger within said inner cylindrical portion to said lower cylindrical portion and generally along said second fluid passage from said lower cylindrical part to said upper cylindrical part outside of said inner cylindrical part, where said vapor-permeable base of said inlet chamber is divided into a plurality of subsections, including a first subsection and a second subsection, each subsection defining a first and second radial center line, respectively, each of said first subsection and said second subsection has at least one louvered flat section containing a plurality of louvered dampers located in the first and second specific directions, respectively, for directing said superheated steam in the first and second discharge directions to said lower inner cylindrical wall , said specific direction of said shutters of said first subsection defines a first angle relative to said first radial center line, said specific direction of said louvres of said second subsection defines a second angle relative to said second radial center line, and said first angle and/or said second angle is different from 0 degrees. 2. The device according to claim 1, wherein said first angle numerically exceeds said second angle by 7.5-90 degrees, preferably numerically exceeds said second angle by 10-60 degrees. 3. The device according to claim. 1 or 2, in which the specified vapor-permeable base of at least the specified inlet chamber has a third subsection located between the specified first and the specified second subsection and having a third radial center line, the specified intermediate third subsection has at least one louvre a flat section containing a plurality of louvered dampers located in a third specific direction, for directing said superheated steam in the discharge direction towards said lower inner cylindrical wall, said third specific direction of said louvered dampers defines a third angle relative to said corresponding third radial center line, with this third angle is not equal to 0 degrees and is from 0 to 90 degrees, preferably from 10 to 60 degrees. 4. The device according to any of the previous claims, in which at least the inlet chamber has a transitional flat section located as a transitional section between the specified vapor-permeable base and the specified internal cylindrical part, the specified transitional flat section has a louvered flat section for directing the flow of superheated steam in the direction direction of injection towards said lower inner cylindrical wall, said injection direction defines an angle in the vertical direction and, compared to the horizontal plane, said angle is -80 to 80 degrees, preferably -60 to 60 degrees, more preferably -40 to 40 degrees, most preferably -40 to 0 degrees. 5. An apparatus according to any one of the preceding claims, wherein said sub-sections comprise a plurality of louvered flat sections, said particular direction of the two or more said louvered flat sections defines a different angle relative to said radial center line, respectively. 6. Apparatus according to any one of the preceding claims, wherein said vapor-permeable base comprises a plurality of openings for directing said superheated steam in a substantially vertical discharge direction, wherein the open area of said louvres of said inlet chamber forms an area of 10 to 90% of the total open area of all said openings and louvres of said vapor-permeable base of said inlet chamber, preferably from 20 to 60%, more preferably from 30 to 50%, for example from about 40 to 50%. 7. Component vapor-permeable base for the device according to any one of paragraphs. 1-6, moreover, the specified component of the vapor-permeable base has at least one subsection defining a radial center line, said subsection has a louvered flat section having a plurality of louvered dampers arranged in a specific direction to direct said superheated steam in the discharge direction towards said lower inner cylindrical wall, said specific direction of said louvered dampers defines an angle relative to said first radial center line, said angle is in the range of 7.5 to 90 degrees numerically, preferably 10 to 75 degrees, preferably 11.5 to 60 degrees. 8. Method for drying bulk granular materials by providing a device containing: a container defining a lower cylindrical part, having a lower inner cylindrical wall and defining a first cross-sectional region perpendicular to the length of the lower cylindrical part, and an upper cylindrical part defining a second cross-sectional region perpendicular to the length of the upper cylindrical part, an inner cylindrical part located centrally inside said upper cylindrical part and said lower cylindrical part of said container to form a first fluid channel from said upper cylindrical part to said lower cylindrical part inside said inner cylindrical part and a second fluid channel from said the lower cylindrical part to the specified upper cylindrical part outside the specified inner cylindrical part, a plurality of dividing walls extending in the radial direction inside said lower cylindrical part between said lower cylindrical part and said inner cylindrical part and defining in said lower cylindrical part an inlet chamber, an outlet chamber and a plurality of intermediate chambers located between said inlet chamber and said outlet chamber in circumferential direction, while the specified inlet chamber contains an inlet, said outlet chamber contains an outlet, each of said inlet chamber and said intermediate chambers defines a vapor-permeable base, said outlet chamber defines a vapor-tight base, said vapor-permeable base of said inlet chamber is configured to receive superheated steam from the impeller, said vapor-permeable base is configured to direct the flow of superheated steam in a plurality of directions to said lower inner cylindrical wall and in directions different from the radial direction of the vapor-permeable base, a heat exchanger located inside said inner cylindrical part, and an impeller, said method includes steps in which: • maintain superheated steam inside the specified container at a pressure that is equal to or greater than the pressure of the medium surrounding the container, • receive wet bulk granular material at the indicated inlet, • heating said steam inside said heat exchanger, • superheated steam flow is generated along said first fluid channel from said upper cylindrical part through said heat exchanger inside said inner cylindrical part to said lower cylindrical part, and through said vapor-permeable base, superheated steam flow is directed in a plurality of directions different from said radial direction , toward said lower inner cylindrical wall, and generally along said second fluid passage from said lower cylindrical portion to said upper cylindrical portion outside said inner cylindrical portion, by using said impeller, thereby increasing the velocity and swirl of the superheated steam , And • release dry bulk granular material at the specified outlet. 9. The method according to claim 8, in which, through the specified vapor-permeable base, the specified flow of superheated steam is directed in the first direction to the specified lower inner cylindrical wall, defining the first angle relative to the specified radial direction, and in the second direction to the specified lower inner cylindrical wall, defining the second an angle relative to said radial direction, wherein said first angle is different from said second angle. 10. The method according to p. 8 or 9 drying bulk granular materials by providing a device according to any one of paragraphs. 1-6.