WO2010010585A1 - Appareil de séchage - Google Patents

Appareil de séchage Download PDF

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Publication number
WO2010010585A1
WO2010010585A1 PCT/IT2008/000501 IT2008000501W WO2010010585A1 WO 2010010585 A1 WO2010010585 A1 WO 2010010585A1 IT 2008000501 W IT2008000501 W IT 2008000501W WO 2010010585 A1 WO2010010585 A1 WO 2010010585A1
Authority
WO
WIPO (PCT)
Prior art keywords
drier
accordance
biomass
ring gear
wall
Prior art date
Application number
PCT/IT2008/000501
Other languages
English (en)
Inventor
Giovanni Cappello
Original Assignee
A.G.T. Srl
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by A.G.T. Srl filed Critical A.G.T. Srl
Priority to PCT/IT2008/000501 priority Critical patent/WO2010010585A1/fr
Publication of WO2010010585A1 publication Critical patent/WO2010010585A1/fr
Priority to SM201100005T priority patent/SMP201100005B/it

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B9/00—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards
    • F26B9/06—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards in stationary drums or chambers
    • F26B9/063—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards in stationary drums or chambers for drying granular material in bulk, e.g. grain bins or silos with false floor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B25/00—Details of general application not covered by group F26B21/00 or F26B23/00
    • F26B25/04—Agitating, stirring, or scraping devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B9/00—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards
    • F26B9/06—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards in stationary drums or chambers
    • F26B9/08—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards in stationary drums or chambers including agitating devices, e.g. pneumatic recirculation arrangements
    • F26B9/082—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards in stationary drums or chambers including agitating devices, e.g. pneumatic recirculation arrangements mechanically agitating or recirculating the material being dried
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B9/00—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards
    • F26B9/10—Machines or apparatus for drying solid materials or objects at rest or with only local agitation; Domestic airing cupboards in the open air; in pans or tables in rooms; Drying stacks of loose material on floors which may be covered, e.g. by a roof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B2200/00—Drying processes and machines for solid materials characterised by the specific requirements of the drying good
    • F26B2200/24—Wood particles, e.g. shavings, cuttings, saw dust

Definitions

  • Subject of the present invention is a drying plant or drier for biomasses, in particular a drier of small/mid-size dimensions fed with low temperature air for biomasses used in production processes of energy, heat or for food purposes .
  • Biomass is generally composed of wood chips, agricultural production waste, corn stubbles, wheat straw and rice straw, sorghum stubbles, sugar cane bagasse, common cane etc.
  • the drying plants of the first category are characterised by large-size silos (up to several thousand cubic meters) .
  • the moist material is loaded from the upper part of the silo and extracted from the lower part of the same.
  • the hot air crosses the material in a counter-current manner, from the bottom towards the top, ensuring optimal heat exchange efficiency.
  • screws are commonly used which are capable of making the biomass converge towards an outlet placed at the centre of the silo.
  • the screws are rotatable along their own axis (for transporting the dry biomass) and rotatable on the bottom of the silos (for reaching all the dry biomass) .
  • Such screws are thus extremely critical pieces from a mechanical standpoint, and thus are rather costly.
  • This first plant type thus requires large sizes for damping the great cost of the material discharge screw.
  • This solution type has an ideal use in large plants which treat wood chips for paper mills and/or which treat biomass for energy production.
  • These driers are also characterised by high residence times of the material (several hours) , in connection with the possibility of using low temperature hot air (less than 100 0 C) with high drying efficiencies.
  • the plants of the second category are characterised by the use of a perforated conveyor belt on which the biomass is extended.
  • the hot air crosses the biomass extended on the moving belt, drying it.
  • These plants are characterised by a low drying efficiency, since part of the hot air crosses already-dried zones of the biomass. This drawback can be prevented by optimising the flow of the hot air. In this manner, however, there is a considerable increase of the plant costs.
  • These driers are characterised by low residence times (less than an hour) , use of hot air at medium temperature (between 100 0 C and 200 0 C) and medium-low drying efficiencies. Plants of this type usually are of medium size (between 100m 3 and 200m 3 ) and are used for flow rates up to 10m 3 /h.
  • the plants of the third category are characterised by a rotating drum crossed by the hot air, in which the material is continuously moved and advanced by the drum movement. These plants are characterised by medium/low residence times (about 30 minutes) , by the need to use high temperature hot air (over 200 0 C) in order to not use overly large structural sizes and excessive manufacturing costs. In addition, if the speed of the air around the drum is sufficiently high, a driving effect is produced of the finest material, creating an excess dust problem at the exhaust and thus the need to introduce dust removal means . [0015]
  • the object of the present invention is therefore that of providing a drier adapted to at least partially overcome the drawbacks marked with reference to the prior art .
  • one task of the present invention is that of providing a drier for biomasses of medium/small size (not more than 100m 3 ) .
  • Still another task of the present invention is that of providing a drier capable of using low temperature hot air (less than 100 0 C) and with high efficiency.
  • Further tasks of the present invention are those of providing a drier characterised by a low dust level of the exiting air; by a continuous functioning, even in the presence of extraneous bodies inside the supply biomass; by the possibility of functioning with hard-to-treat biomasses (wood chips and cut-up sorghum, for example) ; and by limited initial investments and operating costs.
  • Such object and such tasks are achieved by means of a drier according to claim 1.
  • FIG. 2 is a view of the section obtained along the trace II-II of figure 1;
  • - Figure 3 is a top view of the drier;
  • - Figure 4 is a view of the section obtained along the trace IV-IV of figure 3;
  • FIG. 5 is a view of the section obtained along the trace V-V of figure 1;
  • Figure 9 is a perspective view similar to figure 5;
  • FIG. 10 is a perspective view of the detail of figure 6;
  • FIG. 11 is schematic view of a first plant comprising a drier according to the invention.
  • Figure 12 is a schematic view of a second plant comprising a drier according to the invention.
  • a drier according to the invention is indicated in its entirety with the reference 1.
  • the drier 1 according to the invention comprises:
  • a wall 102 for separating the upper space 10 from the lower chamber 11, the wall 102 being adapted to support the biomass and to permit the passage of the hot air; - a mixer 67 adapted to sweep at least a portion of the wall 102; and an extractor 15 placed below the wall 102, the extractor 15 being adapted for extracting the biomass from the space 10.
  • the drier 1 has cylindrical shape with circular section and vertical axis.
  • the shape can be cylindrical with elliptical section or generally prismatic with polygonal section (for example square, pentagonal, hexagonal, heptagonal, octagonal, etc.).
  • the shape of the drier can be at least partially frustoconical and/or frusto-pyramidal .
  • the diameter of the drier 1 is preferably in the range of Im - 20m, preferably 3m - 8m.
  • the upper space 10 is adapted to contain the biomass in a layer in the range of 0.1m - 10m.
  • the lower chamber 11 has the function of dispensing and making uniform the hot air flow which is inserted in the drier 1.
  • the air flow can be generated with different modes, described in detail below.
  • a suitable heating element can be used, or the heat can be recovered from other external sources. Such embodiment will be described in detail below.
  • the wall 102 comprises, at least in some of its parts, grates, nets or perforated plates. By appropriately sizing the openings of the wall 102, this accomplishes the double function of supporting the biomass inside the space 10 and allowing the uniform distribution of the hot air flow in the biomass itself.
  • the drier 1 according to the invention is designed for treating biomass with a minimum size of 3mm x 3mm x 3mm and a maximum size of 100mm x 100mm x 100mm. The openings of the wall 102 are therefore sized on the minimum design size. Small biomass percentages outside the abovementioned standards do not compromise the functioning of the system.
  • the wall 102 at the same time constitutes the bottom of the space 10 and the cover of the chamber 11.
  • the drier 1 comprises an opening 14 in the upper part, for example in the cover 101. This opening 14 is adapted to receive the moist biomass entering in the drier l.
  • the drier 1 also comprises, in its top part, a stack 13.
  • the extractor 15 is positioned below the level of the wall 102 which separates the space 10 from the chamber 11.
  • the extractor 15 can comprise a screw 151, a Redler, a conveyor belt, or other linear transport means adapted for the purpose.
  • the extractor 15 of the biomass is positioned in a suitable, at least partially open channel 152, for example in the upper part, and thus communicating with the space 10 containing the biomass.
  • the dimensions of the extractor 15 and related channel 152 are therefore sized on the maximum design size of the biomass.
  • a counter- current drier i.e. a very efficient drier.
  • the moist biomass enters into the top part of the drier 1 and exits from the bottom part thereof.
  • the hot air enters from the bottom of the drier and exists from the top of the same, for example through the stack 13.
  • the air flow is generated by a fan 12 arranged so as to blow the air in the chamber 11.
  • the air flow could be generated in a different manner.
  • a fan and/or an ejector could be arranged on the stack 13 so as to suction the air from the space 10.
  • the air flow could be simultaneously generated by a fan which blows in the chamber 11 and by a fan/ejector which suctions from the stack 13.
  • the mixer 67 comprises a ring gear 16 on which one or more furrowing elements 17 are mounted.
  • the mixer 67 is preferably arranged on the bottom of the space 10.
  • the ring gear 16 has a diameter substantially equal to that of the wall 102, and is therefore arranged in the peripheral zone of the wall 102.
  • the furrowing elements 17 can for example be chains, cables, cords or rigid rods.
  • one end of the chain 17 is fixed to the inside of the ring gear 16 and the other end is fixed to a pinion 18.
  • the pinion 18 and the ring gear 16 are rotatable around a common axis.
  • the chain 17 is generically arranged along a radius of the ring gear 16.
  • both ends of the furrowing element 17 are connected, at different points, inside the ring gear 16, without passing from a central pinion 18.
  • the furrowing element 17 can be arranged along a cord, or in the absence of central bulk, along a diameter of the ring gear 16.
  • the ring gear 16 is substantially parallel to the wall 102 and arranged immediately above it. In this manner, the chains 17 (or other furrowing elements) sweep the surface of the wall 102, being moved just a few centimetres from it. [0041] As seen in figures 4 - 6 and 10, the ring gear 16 is moved by a motor 40 by means of a gear wheel 20.
  • the continuous movement of the ring gear 16 and consequently of the chain 17 constantly mixes the biomass in the bottom zone of the space 10 where it is drier.
  • the continuous mixing of the biomass has various positive effects. First of all, it ensures the movement of the biomass itself towards the channel 152 of the extractor 15, which is fed by dropping. Then, it constantly breaks the bridges which can be formed in the biomass, bridges which could block the drop of the biomass itself into the channel 152 of the extractor 15.
  • the presence of the ring gear 16 arranged on the outer circumference of the swept area allows considerably lightening the furrowing elements.
  • these are elements sized for essentially working via traction and can thus be much lighter than elements of equal length sized for opposing bending loads. For this reason, chains, cords or cables can be employed, while the possible rigid rods are intended for simple connecting rod function.
  • the ring gear 16 is held in position by guide elements 19 arranged along its circumference.
  • guide elements 19 allow a secure positioning of the ring gear 16, independent of its connection to a central pin.
  • Such guide elements can comprise rollers 19, as is well illustrated in the attached figures 5 and 8-10. Otherwise, in other embodiments, the guide elements can be gear wheels, sliding blocks or other similar solutions .
  • the position of the guide elements 19 is adjustable, mainly along the radial direction of the ring gear 16.
  • the ring gear 16 does not comprise a conventional cylindrical toothing with involute profile. Due to the large diameter of the ring gear 16 and the relatively non- stringent tolerances, a toothing has been advantageously chosen constituted by a series of pins 161 or rollers positioned along the circumference of the ring and spaced by the pitch defined by the gear wheel 20 moved by the motor 40. Such solution allows considerably limiting the manufacturing costs of the ring gear 16.
  • the drier 1 comprises a secondary extractor 30, similar to the extractor 15. The secondary extractor 30 is placed in the bottom zone of the chamber 11 and has the function of automatically extracting the dust and the biomass of smaller size than the minimum design size which could possibly fall from the wall 102 into the chamber 11.
  • the drier 1 can be uncovered.
  • the drier 1 is closed by a cover 101.
  • Such cover 101 accomplishes two functions: it prevents the entrance of meteoric water on the biomass, and at the same time it avoids the dispersion of dust in the environment.
  • the drier 1 comprises a treatment device of the air exiting through the stack 13. As a function of the current laws, it may in fact be necessary to remove the dust and/or possible polluting substances.
  • the drier 1 according to the invention allows the treatment of biomasses, grains and the like, whether intended for the paper industry, for the production of energy or for the food sector .
  • the plant in its minimum form of figure 11, comprises a drier 1 as described above and a gasifier.
  • the moist biomass is inserted in the drier where the excess moisture is removed.
  • the dry biomass exiting from the drier is fed to the gasifier. Inside the gasifier the biomass is transformed into fuel gas, which is in turn made available .
  • the gas Upon exiting from the gasifier, the gas generally has a temperature in the range of about 600 0 C to about 700 0 C. In view of the subsequent uses, it must be cooled, thus making available a certain amount of heat. Such heat can be usefully employed for the functioning of the drier, in particular it can be supplied to the air flow entering into the chamber 11 of the drier. This plant configuration therefore allows exploiting a clear synergy between the drier and the gasifier .
  • the plant in the embodiment of figure 12, comprises a drier 1 as described above, a gasifier and an internal combustion engine.
  • the moist biomass is inserted into the drier, where the excess moisture is removed.
  • the dry biomass exiting from the drier is supplied to the gasifier.
  • the biomass Inside the gasifier, the biomass is transformed into fuel gas, which is then in turn supplied to the internal combustion engine. Inside the engine, the fuel gas is transformed into mechanical power which is in turn made available .
  • this plant type is capable of similarly exploiting also the heat deriving from the cooling of the cooling of the engine, as well as that contained in the exhaust gas.
  • This plant configuration therefore allows exploiting a clear synergy between the drier, the gasifier and the internal combustion engine.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Drying Of Solid Materials (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

L'invention concerne un séchoir (1) pour biomasse comprenant : un espace supérieur (10) pour contenir la biomasse ; une chambre inférieure (11) pour la diffusion d'air chaud ; une paroi (102) pour séparer l'espace (10) de la chambre (11) supportant la biomasse et permettant le passage de l'air chaud ; un mélangeur (67) adapté pour balayer une partie de la paroi (102) ; et un extracteur (15) placé en dessous de la paroi (102) et adapté pour extraire la biomasse de l'espace (10).
PCT/IT2008/000501 2008-07-25 2008-07-25 Appareil de séchage WO2010010585A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/IT2008/000501 WO2010010585A1 (fr) 2008-07-25 2008-07-25 Appareil de séchage
SM201100005T SMP201100005B (it) 2008-07-25 2011-01-19 Impianto di essicazione.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/IT2008/000501 WO2010010585A1 (fr) 2008-07-25 2008-07-25 Appareil de séchage

Publications (1)

Publication Number Publication Date
WO2010010585A1 true WO2010010585A1 (fr) 2010-01-28

Family

ID=40467213

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IT2008/000501 WO2010010585A1 (fr) 2008-07-25 2008-07-25 Appareil de séchage

Country Status (2)

Country Link
SM (1) SMP201100005B (fr)
WO (1) WO2010010585A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103453738A (zh) * 2013-08-28 2013-12-18 江苏高皓工业炉有限公司 一种烘箱
CN109916165A (zh) * 2019-03-01 2019-06-21 广州市盈夏机械技术有限公司 一种节能环保多功能双立罐滚筒烘干机
CN111504038A (zh) * 2020-04-29 2020-08-07 安徽盛康药业有限公司 一种医药中间体干燥设备
CN115265116A (zh) * 2022-08-09 2022-11-01 东营市京都科学器材有限责任公司 一种玻璃仪器烘干器

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE875475C (de) * 1950-09-27 1953-05-04 Borsig Ag Vorrichtung zum Auflockern koerniger Massen, vorzugsweise fuer das Ausdaempfen feuchter Saatgut-Extraktionsrueckstaende
US2657031A (en) * 1951-09-04 1953-10-27 Arid Aire Mfg Company Grain drier
GB711152A (en) * 1951-06-01 1954-06-23 Agricultural And Ind Dryers Lt Improved apparatus for producing warm dry air
US3449840A (en) * 1967-10-18 1969-06-17 Clayton & Lambert Mfg Co Continuous grain drying apparatus
US3532232A (en) * 1968-12-09 1970-10-06 Eugene G Sukup Apparatus for evenly evacuating grain from a grain drying bin
US3755917A (en) * 1972-04-03 1973-09-04 Clayton & Lambert Manuf Co Rotary sweep apparatus for drying wet grain
DE2533914A1 (de) * 1975-07-30 1977-02-10 Ruhrkohle Ag Trockner fuer feinkoerniges schuettgut
EP0015357A1 (fr) * 1979-03-07 1980-09-17 Per Ake Nilsson Appareil pour le séchage du fumier et de produits résiduels similaires
DE3724061A1 (de) * 1987-07-21 1989-02-02 Seeger Ind Sa Be- und entladevorrichtung fuer einen maelzereibehaelter
US4888882A (en) * 1986-09-01 1989-12-26 Rolf Ryham Method and apparatus for drying a particulate material such as bark
DE19745422A1 (de) * 1997-10-15 1999-04-22 Univ Halle Wittenberg Integriertes Verfahren zur Verwertung von Abfall
FR2850879A1 (fr) * 2003-02-12 2004-08-13 Blue Ind Systeme de brassage de poudre

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE875475C (de) * 1950-09-27 1953-05-04 Borsig Ag Vorrichtung zum Auflockern koerniger Massen, vorzugsweise fuer das Ausdaempfen feuchter Saatgut-Extraktionsrueckstaende
GB711152A (en) * 1951-06-01 1954-06-23 Agricultural And Ind Dryers Lt Improved apparatus for producing warm dry air
US2657031A (en) * 1951-09-04 1953-10-27 Arid Aire Mfg Company Grain drier
US3449840A (en) * 1967-10-18 1969-06-17 Clayton & Lambert Mfg Co Continuous grain drying apparatus
US3532232A (en) * 1968-12-09 1970-10-06 Eugene G Sukup Apparatus for evenly evacuating grain from a grain drying bin
US3755917A (en) * 1972-04-03 1973-09-04 Clayton & Lambert Manuf Co Rotary sweep apparatus for drying wet grain
DE2533914A1 (de) * 1975-07-30 1977-02-10 Ruhrkohle Ag Trockner fuer feinkoerniges schuettgut
EP0015357A1 (fr) * 1979-03-07 1980-09-17 Per Ake Nilsson Appareil pour le séchage du fumier et de produits résiduels similaires
US4888882A (en) * 1986-09-01 1989-12-26 Rolf Ryham Method and apparatus for drying a particulate material such as bark
DE3724061A1 (de) * 1987-07-21 1989-02-02 Seeger Ind Sa Be- und entladevorrichtung fuer einen maelzereibehaelter
DE19745422A1 (de) * 1997-10-15 1999-04-22 Univ Halle Wittenberg Integriertes Verfahren zur Verwertung von Abfall
FR2850879A1 (fr) * 2003-02-12 2004-08-13 Blue Ind Systeme de brassage de poudre

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103453738A (zh) * 2013-08-28 2013-12-18 江苏高皓工业炉有限公司 一种烘箱
CN109916165A (zh) * 2019-03-01 2019-06-21 广州市盈夏机械技术有限公司 一种节能环保多功能双立罐滚筒烘干机
CN111504038A (zh) * 2020-04-29 2020-08-07 安徽盛康药业有限公司 一种医药中间体干燥设备
CN115265116A (zh) * 2022-08-09 2022-11-01 东营市京都科学器材有限责任公司 一种玻璃仪器烘干器

Also Published As

Publication number Publication date
SMP201100005B (it) 2011-05-06
SMAP201100005A (it) 2011-03-07

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