DK179273B1 - A cooling system and a method of supplying cooled intake air to a fluid bed dryer - Google Patents

A cooling system and a method of supplying cooled intake air to a fluid bed dryer Download PDF

Info

Publication number
DK179273B1
DK179273B1 DKPA201500373A DKPA201500373A DK179273B1 DK 179273 B1 DK179273 B1 DK 179273B1 DK PA201500373 A DKPA201500373 A DK PA201500373A DK PA201500373 A DKPA201500373 A DK PA201500373A DK 179273 B1 DK179273 B1 DK 179273B1
Authority
DK
Denmark
Prior art keywords
air
flow path
air flow
fluid bed
cooling system
Prior art date
Application number
DKPA201500373A
Other languages
Danish (da)
Inventor
Thomas Rønnow Olesen
Rasmus Toftegaard
Original Assignee
Cotes As
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 Cotes As filed Critical Cotes As
Priority to DKPA201500373A priority Critical patent/DK179273B1/en
Priority to PCT/DK2016/050231 priority patent/WO2017000967A1/en
Publication of DK201500373A1 publication Critical patent/DK201500373A1/en
Application granted granted Critical
Publication of DK179273B1 publication Critical patent/DK179273B1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B21/00—Arrangements or duct systems, e.g. in combination with pallet boxes, for supplying and controlling air or gases for drying solid materials or objects
    • F26B21/06—Controlling, e.g. regulating, parameters of gas supply
    • F26B21/08—Humidity
    • F26B21/083—Humidity by using sorbent or hygroscopic materials, e.g. chemical substances, molecular sieves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B3/00—Drying solid materials or objects by processes involving the application of heat
    • F26B3/02—Drying solid materials or objects by processes involving the application of heat by convection, i.e. heat being conveyed from a heat source to the materials or objects to be dried by a gas or vapour, e.g. air
    • F26B3/06—Drying solid materials or objects by processes involving the application of heat by convection, i.e. heat being conveyed from a heat source to the materials or objects to be dried by a gas or vapour, e.g. air the gas or vapour flowing through the materials or objects to be dried
    • F26B3/08—Drying solid materials or objects by processes involving the application of heat by convection, i.e. heat being conveyed from a heat source to the materials or objects to be dried by a gas or vapour, e.g. air the gas or vapour flowing through the materials or objects to be dried so as to loosen them, e.g. to form a fluidised bed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
    • F24F3/12—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling
    • F24F3/14—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification
    • F24F3/1411—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification by absorbing or adsorbing water, e.g. using an hygroscopic desiccant
    • F24F3/1423—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification by absorbing or adsorbing water, e.g. using an hygroscopic desiccant with a moving bed of solid desiccants, e.g. a rotary wheel supporting solid desiccants

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Microbiology (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Central Air Conditioning (AREA)

Abstract

A cooling system for supplying, and a method of supplying, cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a warm or hot material in said fluid bed dryer (20); said method comprising in a cooling system according to the invention, supplying primary air along a primary air flow path (41) to a dry side of an indirect evaporative cooler (40), and secondary air along a secondary air flow path (42a,42b) to a wet side of said same indirect evaporative cooler (40); permitting said primary air to traverse said dry side of said indirect evaporative cooler (40), thereby becoming cooled intake air, and permitting said secondary air to traverse said wet side of said indirect evaporative cooler (40), thereby becoming cooled and moist secondary air; and supplying said cooled intake air to said fluid bed dryer (20) via a fluid bed dryer intake air flow path (21) connecting said dry side of said indirect evaporative cooler (40) to said fluid bed dryer (20).

Description

<1θ> DANMARK (10)
Figure DK179273B1_D0001
<12> PATENTSKRIFT
Patent- og
Varemærkestyrelsen (51) Int.CI.: F24F 5/00(2006.01) F26B 3/08(2006.01) F26B 3/12(2006.01) (21) Ansøgningsnummer: PA 2015 00373 (22) Indleveringsdato: 2015-07-01 (24) Løbedag: 2015-07-01 (41) Aim. tilgængelig: 2017-01-02 (45) Patentets meddelelse bkg. den: 2018-03-26 (73) Patenthaver: COTES A/S, Ndr.Ringgade 70C, 4200 Slagelse, Danmark (72) Opfinder: Thomas Rønnow Olesen, Høgevænget 35, 8370 Hadsten, Danmark Rasmus Toftegaard, Agervej 13, 8320 Mårslet, Danmark (74) Fuldmægtig: Zacco Denmark A/S, Arne Jacobsens Allé 15, 2300 København S, Danmark (54) Benævnelse: A cooling system and a method of supplying cooled intake air to a fluid bed dryer (56) Fremdragne publikationer:
US 6018953 A US 5890372 A US 4910971 A WO 95/14644 A1 US 2008/230051 A1 (57) Sammendrag:
A cooling system for supplying, and a method of supplying, cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a warm or hot material in said fluid bed dryer (20); said method comprising in a cooling system according to the invention, supplying primary air along a primary air flow path (41) to a dry side of an indirect evaporative cooler (40), and secondary air along a secondary air flow path (42a,42b) to a wet side of said same indirect evaporative cooler (40); permitting said primary air to traverse said dry side of said indirect evaporative cooler (40), thereby becoming cooled intake air, and permitting said secondary air to traverse said wet side of said indirect evaporative cooler (40), thereby becoming cooled and moist secondary air; and supplying said cooled intake air to said fluid bed dryer (20) via a fluid bed dryer intake air flow path (21) connecting said dry side of said indirect evaporative cooler (40) to said fluid bed dryer (20).
Fortsættes ...
O
CO
Figure DK179273B1_D0002
Figure 7
TITLE
A cooling system and a method of supplying cooled intake air to a fluid bed dryer.
FIELD
In the field of drying systems and fluid bed drying there is suggested a cooling system with improved energy efficiency for providing cold and dry intake air to a fluid bed dryer and a method of supplying cooled intake air to a fluid bed dryer.
BACKGROUND
In the industrial production of powders such as e.g. milk powders, cheese powders, or pharmaceutical powders it is routinely a part of the production line that a starting material is in a first step spray dried in a spray dryer to the generate the powderous material or powder which is followed in a second step by fluid bed drying wherein the powderous material or powder is cooled and further dried. This two-step process is often necessary due to the high exit temperature of the powder from the spray dryer, which renders the generated powders highly hygroscopic during cool-down to ambient temperatures.
In the fluid bed dryer, drying is typically a multi-step process characterized by supplying dry intake air to the fluid bed dryer wherein the dry intake air is being reduced in temperature from a starting temperature which is comparable to the exit temperature of the powder from the spray dryer to, or comparable to, ambient temperature in a series of consecutive steps, often two, by lowering the temperature of the dry intake air between steps. A conventional process of the art is described in WO 95/ 14644.
P81700245DK00
In the art it is customary to manufacture cooled and dry intake air for the fluid bed drying process by passing ambient air through a condensation dryer, typically comprising an ice-water unit. Here the air is cooled to below the dew-point where, in response, the air exudes water and the absolute humidity [g/kg] is reduced. However, because the temperature drops concomitantly the relative humidity increases towards 100%. This constitutes a significant problem for the subsequent drying. To compensate for this drawback, the drying air is subsequently heated.
Conventional drying air systems in the art have several drawbacks some of which are listed here. They are unnecessary energy demanding, as energy is required both for cooling and for subsequent heating, and they pose a significant hygiene problem as both the condensation water and the resulting high humidity pose a significant risk for bacterial growth in the condensation cooler, whereby bacteria subsequently are at risk of being transported by the air-flow into the powder product. This can partially be compensated for by the heating being carried out in an adsorption de-moisturizer, which at the same time heats the intake air and reduces bacterial inflow, however the system remains unnecessary energy demanding.
It is the aim of the present invention to solve at least some of the above problems of drying air systems for fluid bed dryers. To this purpose the present inventors suggest the use of indirect evaporative cooling for drying and cooling intake air for fluid bed dryers as detailed in the claims and description of the present disclosure .
US 6,018,953 describes a method of conditioning a process stream of air to a building in an air conditioning system wherein a process stream of air is dehumidified and
P81700245DK00 cooled to provide a conditioned stream of air for introduction to a conditioned space. The method comprises the steps of providing an adsorption wheel having a multiplicity of passages through which process air can flow for adsorbing moisture therefrom, the wheel capable of adsorption of moisture from the process air and of regeneration on a continuous basis as the wheel rotates. An indirect evaporative cooler is provided having a dry side and a wet side separated by a moisture-impervious wall wherein heat is extracted from said dry side through the wall to the wet side. Cooling in the dry side is achieved by evaporation of water into air passing through the wet side. The process air is passed through the adsorption wheel to remove moisture therefrom to provide a moisture-depleted stream of process air exiting the adsorption wheel. The adsorption wheel is regenerated by passing hot gases therethrough to remove moisture from the adsorption wheel. The moisture-depleted stream of process air exiting said adsorption wheel is divided into a relatively hot stream and a relatively cool stream, and the relatively hot stream of process air is introduced into the wet side of the indirect evaporative cooler, and the relatively cool stream is introduced into the dry side, the relatively hot stream evaporating water thereinto thereby cooling the moisture-impervious wall and removing heat from the relatively cool stream to provide cooled air to be introduced to a conditioned space. The air flow rates provided by this system to the building spaces are between 2 to 5 m/s and laminar flows with Reynolds numbers not exceeding 2000.
Other systems for conditioning air for buildings are detailed in e.g. US 5890372 and US 4910971. Due to the intended use for buildings of the cooling systems of the prior art, they are not suited for use with fluid bed dryers, which require very fast flowing air masses to achieve fluidization.
P81700245DK00
WO 2005/106343 details the construction of an enthalpy exchanger (an indirect evaporative cooler in the parlance of the present invention) . The indirect evaporative cooler of WO 2005/106343 Statiqcooling B.V.
is manufactured and sold by of Holland and is considered particularly suitable for use in the systems and units of the present invention.
In the present inexpensive, and invention, we describe simple system that is delivering a dry and cold airstream for ventilating a drying process in a fluid bed dryer. In operation the system creates dry air, thereby eliminating condensation in the ventilation system; and furthermore the outlet and inlet airstreams are separated which minimize the risks of contaminating the inlet air stream.
a flexible, capable of
SUMMARY OF THE INVENTION
The present invention is detailed in the description, the claims and in the drawings. In particular, there is disclosed:
In a first embodiment a cooling system (1,2,3,4,5,6,7) for supplying cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a warm or hot material to be dried in said fluid bed dryer (20); said cooling system (1,2,3,4,5,6,7) comprising: an indirect evaporative cooler (40) comprising a dry side and a wet side; a primary air flow path (41) connecting to said dry side upstream from said indirect evaporative cooler (40); a secondary air flow path (42a,42b) connecting to said wet side upstream and downstream of said indirect
P81700245DK00 evaporative cooler (40), a fluid bed dryer intake air flow path (21) connecting to said dry side downstream from said indirect evaporative cooler (40); said cooling system (1,2,3,4,5,6,7) arranged to permit a flow of intake air for said fluid bed dryer to reach said dry side of said indirect evaporative cooler (40) as primary air along said primary air flow path (41); and arranged to permit a flow of secondary air to reach said wet side of said same indirect evaporative cooler (40) along said
secondary air flow path (42a); permitting said primary
air to traverse said dry side of said indirect
evaporative cooler (40) , thereby becoming cooled intake
air; and permitt ing said secondary air to traverse said
wet side of said indirect evaporative cooler (4 0),
thereby becoming cooled and moist secondary air; and supplying said cooled intake air to said fluid bed dryer (20) via said fluid bed dryer intake air flow path (21) supplying cooled intake air to a fluid bed dryer (20); said cooling system (1,2,3,4,5,6,7) further comprising air moving units for moving air along said air flow paths (21,41,42a,42b).
In a second embodiment a cooling system (1,2,3,4,5,6,7) according to said first embodiment further comprising a bypass air flow path (43) for directing and mixing a flow of primary air to said cooled intake air exiting said indirect evaporative cooler (40) at a first temperature to obtain cooled intake air of a second temperature, said second temperature higher than said first temperature.
In a third embodiment a cooling system (1,2,3,4,5,6,7) according to either said first or second embodiments further comprising a redirection air flow path (44) for redirecting and/or mixing a flow of cooled primary air to
P81700245DK00 said secondary air upstream from said indirect evaporative cooler (40) along said secondary air flow path (42a).
In a fourth embodiment a cooling system (2,3,5,6,7) according to any of the first to third embodiments further comprising a primary air dehumidifier (50), preferably a desiccant dehumidifier, and most preferably a rotary desiccant wheel, arranged on said primary air flow path (41a,41b) upstream from said indirect evaporative cooler (40).
In a fifth embodiment a cooling system (2,3,5,6,7) according to the fourth embodiment wherein said primary air dehumidifier is a rotary desiccant wheel (50) arranged on said primary air flow path (41a,41b) upstream from said indirect evaporative cooler (40), said rotary desiccant wheel (50) comprising a process section (51) and a regeneration section (52), said primary air flow path (41a,41b) traversing said rotary desiccant wheel (50) by said process section (51); said cooling system further comprising at least one regeneration air heating unit (54) for heating intake air to obtain heated regeneration air, which can be led to said regeneration section (52) of said rotary desiccant wheel (50), along a regeneration air flow path (53) , and at least one air moving unit for moving intake air and heated regeneration air along said regeneration air flow path (53).
In a sixth embodiment a cooling system (2,3,5,6,7) according to the fifth embodiment wherein said at least one regeneration air heating unit (54) has been replaced, at least partially, by heat exchangers (54a, 54b,54c) for recovery of heat stored in release air.
P81700245DK00
In a seventh embodiment a cooling system (2,3,5,6,7) according to either the fifth of the sixth embodiments wherein said at least one regeneration air heating unit (54) is replaced by at least one regeneration air heat exchanger (54) located on one or more exhaust air flow paths (12,22) for release air from a spray dryer (10) and/or said fluid bed dryer (20).
In an eighth embodiment a cooling system (2,3,5,6,7) according to either the fifth of the sixth embodiments wherein said at least one regeneration air heating unit (54) is partially replaced by a primary air heat exchanger (54a) located downstream from said rotary desiccant wheel (50) on a second stretch (41b) of said primary air flow path (41) augmented by a supplementary regeneration air heating unit located on said regeneration air flow path (53) between said heat exchanger (54a) and said rotary desiccant wheel (50).
In a ninth embodiment a cooling system (1,2,3,4,5,6,7) according to any of the previous embodiments wherein the secondary air is dehumidified prior to traversing said wet side of said indirect evaporative dryer (40).
In an tenth embodiment a cooling system (1,2,3,4,5,6,7) according to any of the previous embodiments further comprising a secondary air dehumidifier (60), preferably a desiccant dehumidifier, and most preferably a rotary desiccant wheel, arranged on said secondary air flow path (42a) upstream from said indirect evaporative cooler (40) .
P81700245DK00
In an eleventh embodiment a cooling system (6,7) according to the tenth embodiment wherein said secondary air dehumidifier is a rotary desiccant wheel (60) arranged on said secondary air flow path (42a) upstream from said indirect evaporative cooler (40), said rotary desiccant wheel (60) comprising a process section (61) and a regeneration section (62), said secondary air flow path (42a) traversing said rotary desiccant wheel (60) by said process section (61); said cooling system further comprising at least one secondary air heating unit (64) for heating intake air to obtain heated regeneration air, which can be led to said regeneration section (62) of said rotary desiccant wheel (60), along a regeneration air flow path (63), and at least one air moving unit for moving intake air and heated regeneration air along said regeneration air flow path (63).
In an twelfth embodiment a cooling system (4,5,6,7) according to the eleventh embodiment wherein said at least one secondary air heating unit (64) has been replaced, at least partially, by heat exchangers (54a,54b,54c) for recovery of heat stored in release air.
In a thirteenth embodiment a cooling system (4,5,6,7) according to either the eleventh or the twelfth embodiments wherein said at least one secondary air heating unit (64) is replaced by at least one secondary air heat exchanger (64) located on one or more exhaust air flow paths (12,22) for release air from a spray dryer (10) and/or said fluid bed dryer (20).
In a fourteenth embodiment a cooling system (4,5,6,7) according to either the eleventh to thirteenth embodiments wherein said secondary air heat exchanger
P81700245DK00 (64) and said primary air heat exchanger (54a) is one unit in which said primary (41b) and secondary (42a) air flow paths are crossing and heat exchanging, such that primary air is cooled while regeneration air is heated thereby augmenting the cooling capacity of said indirect evaporative heater (40).
In a fifteenth embodiment a cooling system (2,3,4,5,6,7) according to any of the fourth to fourteenth embodiments wherein said at least one regeneration air heating unit (54) and said at least one secondary air heating unit (64) forms a combined regeneration air and secondary air heating unit, and wherein said air flow paths for regeneration air (53,63) and/or said secondary air flow path (42) are split from each other only after passage of said combined regeneration air and secondary air heating unit.
In a sixteenth embodiment a cooling system (2,3,4,5,6,7) according to any of the fourth to fifteenth embodiments further comprising only one desiccant dehumidifier, said desiccant dehumidifier having sufficient capacity to produce dry air to supply both the needs for primary air and for secondary air, and wherein said primary (41) and said secondary (42) air flow paths are split from each other only after passage of said only one desiccant dehumidifier .
In a seventeenth embodiment a cooling system (2,3,4,5,6,7) according to the sixteenth embodiment wherein said only one desiccant dehumidifier is a rotary desiccant wheel supplying dry air for said spray dryer (10) along a spray dryer drying air flow path (11) and wherein said primary (41) and said secondary (42) air
P81700245DK00 flow paths are in fluid connection with said spray dryer drying air flow path (11).
In an eighteenth embodiment a cooling system (1,2,3,4,5,6,7) according to any of the first to seventeenth embodiments wherein said material to be dried is a powderous material.
In a nineteenth embodiment a fluid bed dryer (20) comprising a cooling system (1,2,3,4,5,6,7) according to any of the first to eighteenth embodiments.
In a twentieth embodiment an arrangement comprising a spray dryer (10) and a fluid bed dryer (20) sequentially arranged to allow transport of a powderous material from said spray dryer (10) to said fluid bed dryer (20), said fluid bed dryer (20) comprising a cooling system (1,2,3,4,5,6,7) according to any of the first to eighteenth embodiments.
In a twenty-first embodiment a method of supplying cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a warm or hot material to be dried in said fluid bed dryer (20); said method comprising in a cooling system according to any of the first to eighteenth embodiments, supplying primary air along a primary air flow path (41) to a dry side of an indirect evaporative cooler (40), and secondary air along a secondary air flow path (42a, 42b) to a wet side of said same indirect evaporative cooler (40); permitting said primary air to traverse said dry side of said indirect evaporative cooler (40), thereby becoming cooled intake air, and permitting said secondary air to traverse said
P81700245DK00 wet side of said indirect evaporative cooler (40), thereby becoming cooled and moist secondary air; and supplying said cooled intake air to said fluid bed dryer (20) via a fluid bed dryer intake air flow path (21) connecting said dry side of said indirect evaporative cooler (40) to said fluid bed dryer (20).
An additional embodiment relates to the use of a fluid bed dryer or an arrangement comprising a spray dryer and a fluid bed dryer for drying a powderous material.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1
Figure 2
Figure 3
Basic cooling system and arrangement according
to the invention .
Basic cooling system and arrangement according
to the invention further comprising a desiccant
dehumidifier .
Basic cooling system and arrangement according
to the invention further comprising heat
Figure 4 exchangers for heating regeneration air.
Basic cooling system and arrangement according
Figure 5
Figure 6
to the invention comprising a secondary air
drying unit.
Basic cooling system and arrangement according
to the invention comprising a secondary air
heating unit.
Basic cooling system and arrangement according
to the invention comprising a secondary air
Figure 7 desiccant dehumidifier.
Basic cooling system and arrangement according to the invention comprising a distant desiccant dehumidifier .
DETAILED DESCRIPTION
P81700245DK00
The basic cooling unit (40) and cooling system (1) according to the invention is disclosed in Figure 1. This basic cooling unit and cooling system forms the starting point for the further disclosed present invention.
embodiments of the
With the present invention, and as detailed in the figures, there is disclosed cooling system (1,2,3,4,5,6,7) for supplying cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a warm or hot material to be dried in said fluid bed dryer (20); said cooling system (1,2,3,4,5,6,7) comprising:
an :4o:
indirect evaporative cooler comprising a dry side and a wet side; a primary air flow path (41) connecting to said dry side upstream from said indirect evaporative cooler (40); a secondary air flow path (42a, 42b) connecting to said wet side upstream and downstream of said indirect evaporative cooler (40); a fluid bed dryer intake air flow path (21) connecting to said dry side downstream from said indirect evaporative cooler (40); said cooling system (1,2,3,4,5,6,7) arranged to permit a flow of intake air for said fluid bed dryer to reach said dry side of said indirect evaporative cooler (40) as primary air along said primary air flow path (41); and arranged to permit a flow of secondary air to reach said wet side of said same indirect evaporative cooler (40) along said secondary air flow path (42a); permitting said primary air to traverse said dry side of said indirect evaporative cooler (40), thereby becoming cooled intake air; and permitting said secondary air to traverse said wet side of said indirect evaporative cooler (40), thereby becoming cooled and moist secondary air; and supplying said cooled intake air to said fluid bed dryer (20) via said fluid bed dryer intake air flow
P81700245DK00 path (21) connecting said dry side of said indirect evaporative cooler (40) to said fluid bed dryer (20); said cooling system (1,2,3,4,5,6,7) further comprising air moving units for moving air along said air flow paths (21,41,42a,42b).
In a preferred embodiment the material to be dried is a powderous material. As the method and cooling unit of the invention has a very low risk of bacterial infestation it is particularly preferred that the powderous material shall be a powderous material in hazard of being infected by bacteria, in particular and even more preferred that the powderous material shall be milk powder, cream powder, cheese powder or pharmaceutical powders, such as e.g. powders for inhalation or powders for tableting.
In a further embodiment of the present invention there is disclosed a method of supplying cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a warm or hot material in said fluid bed dryer (20); said method comprising in a cooling system according to any of the embodiments detailed herein, supplying primary air along a primary air flow path (41) to a dry side of an indirect evaporative cooler (40), and secondary air along a secondary air flow path (42a,42b) to a wet side of said same indirect evaporative cooler (40); permitting said primary air to traverse said dry side of said indirect evaporative cooler (40), thereby becoming cooled intake air, and permitting said secondary air to traverse said wet side of said indirect evaporative cooler (40), thereby becoming cooled and moist secondary air; and supplying said cooled intake air to said fluid bed dryer (20) via a fluid bed dryer intake air flow path (21) connecting said dry side of said
P81700245DK00 indirect evaporative cooler (40) to said fluid bed dryer (20) .
Further there is disclosed a use of an indirect evaporative cooler (40) in a method of supplying cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a warm or hot material in said fluid bed dryer (20); said method comprising supplying primary air along a primary air flow path (41) to a dry side of an indirect evaporative cooler (40), and secondary air along a secondary air flow path (42a,42b) to a wet side of said same indirect evaporative cooler (40); permitting said primary air to traverse said dry side of said indirect evaporative cooler (40), thereby becoming cooled intake air, and permitting said secondary air to traverse said wet side of said indirect evaporative cooler (40), thereby becoming cooled and moist secondary air; and supplying said cooled intake air to said fluid bed dryer (20) via a fluid bed dryer intake air flow path (21) connecting said dry side of said indirect evaporative cooler (40) to said fluid bed dryer (20) .
In Figure 1, a generalized layout of a process plant for producing a powderous material is detailed. The powderous material is generated in a spray dryer (10) as a hot and most often also moist powderous material whereupon it is transported (along the thick black line) to a fluid bed dryer (20). In the fluid bed dryer, the powderous material is further dried and cooled to ambient temperature upon which it is transported (along the thick black line) to a powder collection unit (30) (not detailed) as a dried and cooled powderous material for further use or processing. Not detailed in the drawing
P81700245DK00 are the material this is invention necessary means for transporting between the various process units considered outside the scope of a powderous
In general, the present
The spray dryer (10) can be any type of spray dryer known to the skilled person and the current invention is not limited by this choice. From the spray dryer (10) a spray dryer exhaust air flow path (12) is indicated from where hot and humid exhaust air leaves the spray dryer (10) after partaking in a spray drying procedure. Normally this air is released to the surroundings as release air.
Likewise, the fluid bed dryer (20) can be any type of fluid bed dryer known to the skilled person and the current invention is not limited by this choice. From the fluid bed dryer (20) a fluid bed dryer exhaust air flow path (22) is indicated from where hot and humid exhaust air leaves the fluid bed dryer (20) after partaking in a cooling and drying fluid bed drying procedure. Normally this air is released to the surroundings as release air.
Intake air for cooling and drying in the cooling and drying fluid bed dryer procedure is supplied to the fluid bed dryer (20) via a fluid bed dryer intake air flow path (21) connecting an indirect evaporative cooler (40) to the fluid bed dryer (20). The indirect evaporative cooler (40) together with the above and below detailed air flow paths (21,41,41a,41b,42a,42b, 43,44) form a cooling system (1,2,3,4,5,6,7) .
Further comprised in the cooling system (1,2,3,4,5,6,7) of the invention are a plurality of air moving units for moving air along the air flow paths
P81700245DK00 (21,41,41a,41b,42a,42b,43,44) comprised in the cooling system. Fans are most suitable for use with the present invention as air moving units, however, bellows and pumps may serve the intended purpose as well. Other air moving units as are known to the skilled person are contemplated for inclusion into the invention as well. The skilled person will know how to apply such air moving units according to the design requirements of the system.
separated by a extracted from drawings supplying
Indirect evaporative coolers have a cooling section, often called a dry section or dry side, and an evaporation section, often called a wet section or a wet side. By providing a dry side and a wet side moisture-impervious wall, heat can be (primary) air traversing the indirect evaporative cooler by the dry side through the wall to (secondary) air traversing the indirect evaporative cooler by the wet side. Water is required for the operation of indirect evaporative coolers. In the and in the claims conduits and means for water to the indirect evaporative coolers forming part of the invention have not been indicated or included. The skilled person will know how to supply water to an indirect evaporative cooler for its correct operation .
When in operation, (primary) air traversing the indirect evaporative cooler by the cooling section, the dry side, will cool through heat exchange with the indirect evaporative cooler without absorbing moisture, while (secondary) air traversing the indirect evaporative cooler by the evaporation section, wet side, will absorb water, thereby cooling the indirect evaporative cooler, itself becoming moisture laden and cooler.
P81700245DK00
Throughout the text there is made use of the expressions upstream and downstream relative to the indirect evaporative cooler included in the cooling systems of the invention. Upstream and downstream are used in their conventional meaning, such that air approaching the indirect evaporative cooler is on a flow path upstream of the indirect evaporative cooler, while air moving away from the indirect evaporative cooler is on a flow path downstream from the indirect evaporative cooler.
Numerous indirect evaporation coolers are known in the art and are considered suitable for use with the present invention. However, it is particularly preferred that the indirect evaporation cooler used with the present invention is a counter-flow indirect evaporation cooler as detailed in the drawings of the present disclosure.
One example of a counter-flow indirect evaporation cooler is the wet bulb cooler. In the wet bulb cooler, the secondary air flow as it traverses the wet bulb cooler is continuously cooled to 100% relative humidity and reheated by absorbing heat due to heat exchange with the primary air, whereupon it can absorb more water, cool further, become reheated, and absorb more water etc. This thermodynamic cycle will approach the wet bulb temperature of the secondary air, hence the name.
Another example of a counter-flow indirect evaporation cooler is the dew-point cooler. In dew-point coolers, a fraction of the primary air, typically between 25-40%, is diverted from the primary air flow to be used as secondary air. Such systems are self-suppliant in secondary air and further allows for a lower resulting temperature of the primary air exiting the indirect
P81700245DK00 evaporative cooler as the primary air is cooled towards the dew-point of the primary air, rather than the wet bulb temperature.
Accordingly, the wet-bulb cooler and the dew-point cooler are considered particularly preferred in the present invention .
In Figure 1, a primary air flow path (41) is indicated. Primary air is supplied to the indirect evaporative cooler (40) along a primary air flow path (41), and traverses the indirect evaporative cooler (40) by the cooling section, the dry side, whereupon it is cooled, becoming cooled intake air, and is directed to a fluid bed dryer (20) along a fluid bed dryer intake air flow path (21) after having traversed the indirect evaporative cooler. Secondary air is supplied to the evaporation section, the wet side, of the indirect evaporative cooler (40) along a secondary air flow path (42a,42b).
Also disclosed with the present invention is a fluid bed dryer (20) comprising a cooling system (1,2,3,4,5,6,7) of the present invention and as detailed in the present disclosure, as well as an arrangement comprising a spray dryer (10) and a fluid bed dryer (20) sequentially arranged to allow transport of a powderous material from said spray dryer (10) to said fluid bed dryer (20), said fluid bed dryer (20) comprising a cooling system (1,2,3,4,5,6,7) of the present invention and as detailed herein .
A bypass air flow path (43) is indicated in Figure 1. By supplying a bypass air flow path, primary air can be mixed to the cooled intake air for the fluid bed dryer
P81700245DK00 transported along the fluid bed dryer intake air flow path (21), allowing the temperature of the intake air to be controlled between 0 and 100% of the primary air temperature prior to entering the indirect evaporative cooler, with 100% matching the temperature of the original primary air, and 0% being the temperature of the cooled intake air upon exiting the indirect evaporative cooler without any mixing in of bypassed primary air.
In an exemplary embodiment, the bypass air flow path (43) connects to the fluid bed dryer intake air flow path (21) via an air regulation valve, preferably an air regulation valve for automated gas delivery. In general, and throughout the present disclosure, whenever air flow paths connect, preferably air regulation valves, for automated gas and applied.
the use of air regulation valves delivery, is ubiquitously contemplated
Accordingly, the present invention is not limited by the manner in which air flow paths connect, rather it is considered within the skills of the person in the art how to combine and divide airflows whether by passive or active regulation.
Accordingly, there is disclosed in an embodiment of the invention a method of supplying cooled intake air to a fluid bed dryer (20); wherein said cooled intake air exiting said indirect evaporative cooler (40) at a first temperature is mixed with a fraction of primary air to obtain cooled intake air of a second temperature, said second temperature higher than said first temperature.
Also disclosed is a further comprising directing and mixing cooling system (1) as a bypass air flow a flow of primary air detailed above path (43) for to said cooled
P81700245DK00 intake air exiting the indirect evaporative cooler (40) at a first temperature to obtain cooled intake air of a second temperature, said second temperature higher than said first temperature.
In Figure 1 there is further indicated a redirection air flow path (44). This redirection air flow path can redirect a fraction of cooled intake air exiting said indirect evaporative cooler (40) to said secondary air flow path (42a) prior to, i.e. upstream to, entering said indirect evaporative cooler. Thereby the evaporative capacity of the secondary air can be augmented. When the indirect evaporative cooler (40) is a dew-point cooler, the redirection air flow path (44) is the secondary air flow path (42a) and no further secondary air is supplied beyond the flow redirected along the redirection air flow path (44) from the cooled intake air exiting said indirect evaporative cooler (40).
Accordingly, there is further disclosed a cooling system (1) as detailed above further comprising a redirection air flow path (44) for redirecting and/or mixing a flow of cooled primary air to said secondary air upstream from said indirect evaporative cooler (40) along said secondary air flow path (42a).
It is further contemplated that the cooling system (1) shall comprise a primary air dehumidifier, preferably a desiccant dehumidifier, and most preferably a rotary desiccant wheel dehumidifier, arranged on the primary air flow path (41) upstream from the indirect evaporative cooler (40). A cooling system (2) according to the invention comprising a primary air dehumidifier is
P81700245DK00 detailed in Figure 2 using the most preferred embodiment, the rotary desiccant wheel, as an exemplary embodiment.
By introducing a dehumidifier into the primary air flow path prior to cooling, it can be assured that the cooled intake air entering said fluid bed dryer (20) is also dry. Thereby cooling can take place in the fluid bed dryer without compromising the dryness of the material in the fluid bed dryer. Also significant advantages are obtained in the construction of the cooling systems of the present invention, including energy savings and bacterial growth prevention.
An effect of the drying of the intake air in a desiccant dryer, particularly in the rotary desiccant wheel, is that the heat of absorption stored by the water in the intake air is released such that intake air exiting e.g. the rotary desiccant wheel during operation exits as dried and warmed exit air. The cooling systems of the present invention must compensate for this effect in order to provide adequately cooled air to a fluid bed dryer as contemplated by the invention.
Desiccant dehumidifiers comprise a range of different dehumidifiers with varying desiccants and constructive layouts to match the desiccant. Preferably contemplated for use with the present invention are liquid desiccants, silica gels, zeolites, Preferably, however, the rotary desiccant wheel desiccant, preferably a combination thereof.
and combinations thereof.
desiccant dehumidifier is a comprising a solid state ilica gel, a zeolite, or a
P81700245DK00
When the desiccant dehumidifier is a rotary desiccant wheel, the rotary desiccant wheels for use with the present invention operate according to known principles of operation of rotary desiccant wheels as they are usual in the art of drying moist intake air using rotary desiccant wheels. The present invention is detailed using rotary desiccant wheels (50) comprising only a process section (51) and a regeneration section (52); however, this is solely for exemplary use. The skilled person is aware that it is common to employ one or more purge zones for the operation of rotary desiccant wheels, and may employ such purge zones at his wish without departing from the scope of the present invention.
Further comprised in the cooling system (2) comprising a dehumidifier, is at least one heating unit (54) for heating intake air to obtain heated regeneration air, which can be led to a regeneration section (52) of the dehumidifier, preferably the rotary desiccant wheel (50), along a regeneration air flow path (53).
Accordingly, in an embodiment of the cooling system (2) of the invention there is disclosed a cooling system (2) further comprising a rotary desiccant wheel (50) arranged on said primary air flow path (41a, 41b) upstream from said indirect evaporative cooler (40), said rotary desiccant wheel (50) comprising a process section (51) and a regeneration section (52), said primary air flow path (41a,41b) traversing said rotary desiccant wheel (50) by said process section (51); said cooling system further comprising at least one regeneration air heating unit (54) for heating intake air to obtain heated regeneration air, which can be led to said regeneration section (52) of said rotary desiccant wheel (50), along a
P81700245DK00 regeneration air flow path (53) , and at least one air moving unit for moving intake air and heated regeneration air along said regeneration air flow path (53).
In order for sufficient regeneration of the rotary desiccant wheel (50) the regeneration air should be from about 50°C to about 150°C. Fortunately, which is an advantage of the present invention, numerous sources of reusable heat are present in a spray drying and fluid bed drying plant, wherefore the cost of supplying heated regeneration air is minimal when the plant is in operation. Nevertheless, diverse burners or electricity can be used to supply hot regeneration air from the at least one heating unit (54), however, this is less advantageous from an energy perspective.
In an embodiment of the cooling system (2) further comprising a desiccant dehumidifier, but not detailed in the figure, the bypass air flow path (43) further connects directly to the secondary air flow path (42a) at a position upstream to said indirect evaporative cooler (40). Thereby the cooling capacity of the indirect evaporative cooler (40) can be augmented by dry primary air from the desiccant dehumidifier, e.g. the rotary desiccant wheel (50), thereby increasing the water absorptive capacity of the secondary air, and thereby its cooling capacity.
Following the setup as detailed in figure 2, intake primary air enters the desiccant dryer, in the figure the rotary desiccant wheel (50), along a first stretch (41a) of the primary air flow path (41a, 41b) . It is then dried and heated in the desiccant dryer (50), thereby becoming dried and heated primary air, before being transported
P81700245DK00 along a second stretch (41b) of the primary air flow path (41a,41b) to the indirect evaporative cooler (40) . Upon traversing the dry side of the indirect evaporative cooler, the dried and heated primary air becomes dried and cooled intake air, whereupon it is directed to the fluid bed dryer (20) along a fluid bed dryer intake air flow path (21).
In Figure 3 there is detailed an embodiment of the present invention wherein the desiccant dehumidifier is regenerated using excess energy generated by other processes in the production plant wherein the systems of the invention are installed. In the figure, the at least one regeneration air heating unit (54) detailed in Figure 2 has been replaced, at least partially, by heat exchangers (54a,54b,54c) for recovery of heat stored in release air from the process elements, e.g. spray dryer (10) or fluid bed dryer (20), of the plant.
In one embodiment the at least one regeneration air heating unit (54) is replaced by a regeneration air heat exchanger (54) located on one or more of the exhaust air flow paths (12,22) for release air of the spray dryer (10) and/or the fluid bed dryer (20).
In one embodiment, the regeneration air heating unit (54) is partially replaced by a heat exchanger (54a) located downstream from the desiccant dehumidifier (50), in the preferred embodiment detailed in the drawing a rotary desiccant wheel, on said second stretch (41b) of said primary air flow path. Thereby some of the heat contained in the dried and warmed primary air is removed prior to the air entering the indirect evaporative cooler (40), which will improve the cooling effect of that unit. The
P81700245DK00 regeneration flow path (53) accordingly will cross the second stretch (41b) of the primary air flow path downstream from the desiccant dehumidifier.
However, since only a part of the energy needed for regeneration of the desiccant dryer can be recovered in this manner, a supplementary heating unit (54) will still be needed. In one embodiment, this supplementary heating unit (54) is a conventional heating unit, i.e. a burner
or an electrical heater; however, preferably the
supplementary heating unit is a second heat exchanger as
detailed below.
It is namely one of the significant advantages of the
present invention that heat for regeneration of the desiccant dehumidifiers used in the invention is readily available from the release air of the various process units (spray dryer (10), fluid bed dryer (20) etc.). In Figure 3, this is indicated by heat exchangers (54b, 54c) located at positions on the spray dryer exhaust air flow path (12) and/or the fluid bed dryer exhaust air flow path (22) . The regeneration flow path (53) accordingly crosses these flow paths at the positions of the heat exchangers. When the heat exchanger (54a) located at a position on said second stretch (41b) of said primary air flow path is present, the regeneration temperature can be augmented by further heated air from heat exchangers (54b,54c) located elsewhere in the production plant.
In general, where energy saving is in focus, the solutions comprising desiccant dryers regenerated using heat obtained by heat exchange from exhaust air is preferred. However, if the cooling systems of the present invention are to be installed in existing spray drying
P81700245DK00 and fluid bed drying plants, requirements for space (footprint) and lack of possibility for installing additional heat exchangers on the exhaust air flow paths (12,22) from spray dryer (10) or fluid bed dryer (20) may necessitate a self-contained cooling system of the invention. In such self-contained cooling systems of the invention burners or electrical heaters may be the preferred options.
In a further embodiment of the invention, independently of or in combination with the further embodiments of the invention, the secondary air is dried prior to its entry into the wet side of the indirect evaporative dryer (40). This is detailed in Figure 4.
The secondary air is dried in at least one secondary air drying unit (60) positioned on said secondary air flow path (42a) upstream from said indirect evaporative dryer (40) . The at least one secondary air drying unit (60) preferably is a desiccant dehumidifier of the types discussed previously in the present disclosure.
Drying the secondary air prior to its entry into the wet side of the indirect evaporative dryer has the added advantage of augmenting the cooling capacity of the secondary air, thereby allowing the system to produce either colder intake air for a fluid bed dryer (20) and/or allow a higher production rate of cooled intake air for a fluid bed dryer (20).
Accordingly, there is disclosed a cooling system (4) of the invention further comprising at least one secondary air drying unit (60) for heating the secondary air prior
P81700245DK00 to traversing the wet side of the indirect evaporative dryer (4 0) .
In a further embodiment of the invention, independently of or in combination with the further embodiments of the invention, the secondary air is heated prior to its entry into the wet side of the indirect evaporative dryer (40). This is detailed in Figure 5.
In general, it is unnecessary to heat the secondary air prior to its entry into the wet side of the indirect evaporative dryer (40) as the dew point of the air is not changed by this action. However local climate restrictions may require heating and the embodiment is hereby included by example. However, the embodiments for secondary heating disclosed in connection with Figure 5 are, as will be detailed further below, with little modification very suitable for use with the above detailed drying of the secondary air and is disclosed supplementary to this as detailed further below.
The secondary air is heated in at least one secondary air drying unit (64) positioned on said secondary air flow path (42a) upstream from said indirect evaporative dryer (40) . The at least one secondary air heating unit (64) preferably is a desiccant dehumidifier (60) of the types discussed previously in the present disclosure.
Heating and drying the secondary air prior to its entry into the wet side of the indirect evaporative dryer has the added advantage of augmenting the cooling capacity of the secondary air, thereby allowing the system to produce either colder intake air for the fluid bed dryer (20) and/or allow a higher production rate of cooled intake
P81700245DK00 air for the fluid bed dryer (20) . Accordingly, there is disclosed a cooling system (4) of the invention further comprising at least one secondary air drying unit (60) for heating the secondary air prior to traversing the wet side of the indirect evaporative dryer (40).
In a one embodiment, the heating unit (64) is a heat exchanger. This is detailed in Figure 5 in combination, for exemplary reasons, with the embodiment wherein the cooling system of the invention further comprises a desiccant dehumidifier for drying the primary air.
In one embodiment of the cooling system (5) of the invention further comprising at least one secondary air heating unit (64), the at least one secondary air heating unit being a secondary air heat exchanger (64) positioned on said secondary air flow path (42a) upstream from said indirect evaporative dryer (40) . The embodiment is detailed using the embodiment wherein the cooling system of the invention further comprises a desiccant dehumidifier for drying the primary air for the below reasons, can however just as easily be used independently thereof .
One of the problems in drying the primary air in the desiccant dryer is the concomitant heating thereof. In one embodiment of the cooling system (5) further comprising a secondary air heat exchanger (64), the secondary air heat exchanger (64) and the primary air heat exchanger (54a) are identical. By crossing the primary (41b) and secondary (42a) air flow paths at this position, the primary air is advantageously cooled while the secondary air is advantageously heated and the
P81700245DK00 cooling capacity of the indirect evaporative heater (40) is thereby augmented.
In further embodiments, the secondary air heat exchanger (64) is a heat exchanger (54b, 54c) as indicated in the drawings where the secondary air heat exchanges with exhaust air from process equipment such as a spray dryer (10) or a fluid bed dryer (20) to gain advantage of the energy in form of heat stored in these flows of exhaust air. The secondary air flow path (42a) accordingly crosses these flow paths (12,22) at the positions of these heat exchangers (54b,54c).
As detailed above it is further contemplated that the cooling system (1,2,3,4,5,6,7) shall comprise a secondary air dehumidifier, preferably a desiccant dehumidifier, and most preferably a rotary desiccant wheel dehumidifier, arranged on the secondary air flow path (42a) upstream from the indirect evaporative cooler (40).
A cooling system (6) according to the invention comprising a secondary air dehumidifier (60) is detailed in Figure 6 using the most preferred embodiment, the rotary desiccant wheel, as an exemplary embodiment. As detailed in the figure, the secondary air dehumidifier (60) may be used together with the primary air dehumidifier (50) . It may however also be used without. When the secondary air dehumidifier (60) is a rotary desiccant wheel as detailed in the figure, the cooling system (6) further comprises at least one heating unit (64) for heating intake air to obtain heated regeneration air, which can be led to a regeneration section (62) of the dehumidifier, preferably the rotary desiccant wheel (60), along a regeneration air flow path (63), and a
P81700245DK00 process air section (61) of the same rotary desiccant wheel in parallel to what was detailed above for the rotary desiccant wheel (50) for drying primary air.
Accordingly, in an embodiment of the cooling system (6) of the invention there is disclosed a cooling system (6) further comprising a rotary desiccant wheel (60) arranged on said primary air flow path (42a) upstream from said indirect evaporative cooler (40), said rotary desiccant wheel (60) comprising a process section (61) and a regeneration section (62), said primary air flow path (42a) traversing said rotary desiccant wheel (60) by said process section (61); at least one regeneration air heating unit (64) for heating intake air to obtain heated regeneration air, which can be led to said regeneration section (62) of said rotary desiccant wheel (60), along a regeneration air flow path (63); and an air moving unit for moving intake air and heated regeneration air along said regeneration air flow path (63).
As the secondary air exiting the desiccant dehumidifier will be dry, the cooling capacity of the secondary air is thereby significantly augmented. This in particular may be necessary if the cooling systems of the invention are installed in climates where the ambient air serving as secondary air is already hot and humid.
In one embodiment, as detailed in Figure 6, the at least one secondary air heating unit (64) as detailed above, serves the purpose of the at least one regeneration air heating unit (64) . The unit will however no longer be located on said secondary air flow path (42a) but on said regeneration air flow path (63).
P81700245DK00
In one embodiment, the at least one regeneration air heating unit (54) and the at least one secondary air heating unit (64) forms a combined regeneration air and secondary air heating unit, and wherein the air flow paths for regeneration air (53,63) and/or the secondary air flow path (42) are split from each other only after passage of the combined regeneration air and secondary air heating unit. Thereby equipment and equipment footprint is saved.
E.g. the exhaust air from a spray dryer (10) will typically contain far more energy in the form of heat as is necessary for optimal operation of the cooling systems of the present invention. Therefore an air heat exchanger located at position 54b will usually generate enough heated supply air to the cooling systems of the invention such that any of the processes of the cooling systems requiring heated air in the cooling systems can all be adequately supplied from this one unit. Likewise, where space demands make heat exchange with other process equipment impractical or unfeasible, a single heating unit, e.g. a burner or an electrical heater, may take the place of the separate heating units (54,64) in the manner detailed above.
In one embodiment of the invention, the cooling system (7) comprises only one desiccant dehumidifier which produces enough dry air to supply both the needs for primary air and for secondary air. As can be easily observed from Figure 6, the setup required to operate both desiccant dryers (50,60) are identical so it will be just as expedient to supply one desiccant dryer with the capacity to service both primary and secondary air needs. In the cooling system of this embodiment, both the
P81700245DK00 primary air flow path (41) and the secondary air flow path (42) originate from the same source.
This is detailed in an embodiment in Figure 7. In this embodiment of the invention, a rotary wheel desiccant dryer already forms part of the production plant as a means for supplying hot and dry air to a spray dryer (10) along a spray dryer drying air flow path (11). A part of this dried air for the spray dryer (10) is then diverted as primary air and secondary air, along the primary (41) and secondary (42) air flow paths which are in fluid connection with a spray dryer drying air flow path (11), and used further downstream to cool a powderous material in the fluid bed dryer (20) after passage of the cooling system (7) of the invention.
In the embodiments and aspects of the present invention it has been detailed above how cooling can be undertaken efficiently, and with an improved bacteriological risk profile, by using cooling systems incorporating an indirect evaporative cooler according to the embodiments of the invention.
The invention has been detailed in connection with a fluid bed dryer, however, other drying systems and process equipment where simple, cheap and energy efficient cooling is needed can be used equally well with the cooling systems of the invention in lieu of the fluid bed dryer detailed herein.
CLOSING COMMENTS
The term comprising as used in the claims does not exclude other elements or steps. The term a or an as
P81700245DK00 used in the claims does not exclude a plurality. A single processor or other unit may fulfill the functions of several means recited in the claims.
The skilled person will know how to apply such necessary pipes and air ducts for transporting air through the system flow paths and/or water to the evaporative coolers as required. Likewise, a rotary desiccant wheel is dependent for its operation on adequate rotation of the wheel, which requires one or more motors for rotating the wheel. Other constructional elements for the proper operation may be necessary; however, the skilled person will know how to employ such elements, while not detailed in the present application.
Although the present invention has been described in detail for purpose of illustration, it is understood that such detail is solely for that purpose, and variations can be made therein by those skilled in the art without departing from the scope of the invention as it is defined in the claims.
P81700245DK00

Claims (19)

PATENTKRAV:patent claims: Kølesystem (1,2,3,4,5,6,7) for tilførsel af afkølet indtagsluft til en fluid bed-tørrer (20); hvilket kølesystem (1,2,3,4,5,6,7) omfatter:Cooling system (1,2,3,4,5,6,7) for supplying cooled intake air to a fluid bed dryer (20); which cooling system (1,2,3,4,5,6,7) comprises: - en indirekte fordampningskøler (40), der omfatter en tør side og en våd side;an indirect evaporative cooler (40) comprising a dry side and a wet side; - en primær luftstrømningsvej (41), der forbinder med den tørre side opstrøms fra den indirekte fordampningskøler (40);a primary air flow path (41) connecting to the dry side upstream from the indirect evaporative cooler (40); - en sekundær luftstrømningsvej (42a,42b), der forbinder med den våde side opstrøms (42a) og nedstrøms (42b) for den indirekte fordampningskøler (40) ,a secondary air flow path (42a, 42b) connecting to the wet side upstream (42a) and downstream (42b) of the indirect evaporative cooler (40), - en fluid bed-tørrer-indtagsluftstrømningsvej (21) for forbindelse til en fluid bed-tørrer (20), der forbinder med den tørre side nedstrøms fra den indirekte fordampningskøler (40);- a fluid bed dryer intake air flow path (21) for connecting to a fluid bed dryer (20) connecting to the dry side downstream of the indirect evaporative cooler (40); hvilket kølesystem (1,2,3,4,5,6,7) er indrettet til:which cooling system (1,2,3,4,5,6,7) is arranged for: - at muliggøre et flow af indtagsluft for nævnte fluid bed-tørrer at nå den tørre side af den indirekte fordampningskøler (40) som primær luft ad den primære luftstrømningsvej (41);- enabling a flow of intake air for said fluid bed dryer to reach the dry side of the indirect evaporative cooler (40) as primary air along the primary air flow path (41); - at muliggøre et flow af sekundær luft at nå den våde side af samme indirekte fordampningskøler (40) ad den sekundære luftstrømningsvej (42a);- enabling a secondary air flow to reach the wet side of the same indirect evaporative cooler (40) along the secondary air flow path (42a); - at muliggøre, at den primære luft kan gennemstrømme den tørre side af den indirekte fordampningskøler (40), hvorved den bliver til afkølet indtagsluft;- enabling the primary air to flow through the dry side of the indirect evaporative cooler (40), thereby turning it into cooled intake air; - at muliggøre, at den sekundære luft kan gennemstrømme den våde side af den indirekte fordampningskøler (40), hvorved den bliver til afkølet og fugtig sekundær luft; og- enabling the secondary air to flow through the wet side of the indirect evaporative cooler (40), thereby causing it to cool and moist secondary air; and P81700245DK00P81700245DK00 - at tilføre den afkølede indtagsluft til en fluid bed-tørrer (20) via nævnte fluid bed-tørrerindtagsluftstrømningsvej (21);supplying the cooled intake air to a fluid bed dryer (20) via said fluid bed dryer intake air flow path (21); hvilket kølesystem (1,2,3,4,5,6,7) endvidere omfatter luftbevægelsesenheder til at bevæge luft ad nævnte luftstrømningsveje (21,41,42a,42b); og en bypass-luftstrømningsvej (43) til at lede og blande et flow af primær luft til forlader afkølede indirekte nævnte den der indtagsluft, fordampningskøler (40) ved en første temperatur, til indtagsluft med en anden temperatur, hvilken anden temperatur er højere end nævnte første temperatur.said cooling system (1,2,3,4,5,6,7) further comprising air movement units for moving air along said air flow paths (21,41,42a, 42b); and a bypass air flow path (43) for conducting and mixing a flow of primary air to leave cooled indirectly said intake air, evaporative cooler (40) at a first temperature, to intake air at a second temperature, which temperature is higher than said temperature. first temperature. opnåelse af afkøletobtaining the cooled 2. Kølesystem (1,2,3,4,5,6,7) ifølge krav 1, endvidere omfattende en omdirigeringsluftstrømningsvej (44) til omdirigering og/eller blanding af et flow af afkølet primær luft til den sekundære luft opstrøms (42a) fra den indirekte fordampningskøler (40) ad den sekundære luftstrømningsvej (42a,42b).A cooling system (1,2,3,4,5,6,7) according to claim 1, further comprising a redirect air flow path (44) for redirecting and / or mixing a flow of cooled primary air to the secondary air upstream (42a) from the indirect evaporative cooler (40) along the secondary air flow path (42a, 42b). 3. Kølesystem (2,3,5,6,7) ifølge et hvilket som helst af kravene 1 til 2, endvidere omfattende en affugter (50) til primær luft, fortrinsvis en tørremiddelaffugter og mest foretrukket et roterende tørremiddelhjul, der er anbragt på den primære luftstrømningsvej (41a,41b) opstrøms fra den indirekte fordampningskøler (40).A cooling system (2,3,5,6,7) according to any one of claims 1 to 2, further comprising a dehumidifier (50) for primary air, preferably a desiccant dehumidifier and most preferably a rotary desiccant wheel mounted on the primary air flow path (41a, 41b) upstream from the indirect evaporative cooler (40). 4. Kølesystem (2,3,4. Cooling system (2.3, 5,6,7) ifølge krav 3, hvor den primære luftaffugter er et roterende tørremiddelhjul (50), der er anbragt på den primære luftstrømningsvej (41a,41b) opstrøms fra den indirekte fordampningskøler (40), hvor det roterende tørremiddelhjul (50) omfatter et procesafsnit (51) og et regenereringsafsnit (52), hvor5,6,7) according to claim 3, wherein the primary dehumidifier is a rotary desiccant wheel (50) disposed on the primary air flow path (41a, 41b) upstream of the indirect evaporative cooler (40), wherein the rotary desiccant wheel (50) comprises a process section (51) and a regeneration section (52), wherein P81700245DK00 den primære luftstrømningsvej (41a,41b) gennemstrømmer det roterende tørremiddelhjul (50) ved procesafsnittet (51); hvilket kølesystem endvidere omfatter mindst en regenereringsluft-opvarmningsenhed (54) til opvarmning af indtagsluft til opnåelse af opvarmet regenereringsluft, der kan føres til det roterende tørremiddelhjuls (50) regenereringsafsnit (52), ad en regenereringsluftstrømningsvej (53), og mindst en luftbevægelsesenhed til at bevæge indtagsluft og opvarmet regenereringsluft ad nævnte regenereringsluftstrømningsvej (53) .P81700245DK00 the primary air flow path (41a, 41b) flows through the rotary desiccant wheel (50) at the process section (51); said cooling system further comprising at least one regenerating air heating unit (54) for heating intake air to obtain heated regenerative air which can be fed to the regenerating section (52) of the rotary desiccant (50), along a regenerating air flow path (53), and at least one air wall moving intake air and heated regeneration air along said regeneration air flow path (53). Kølesystem (2,3,5,6,7) ifølge krav 4, hvor den mindst ene regenereringsluftsopvarmningsenhed (54) omfatter en varmeveksler (54a,54b,54c) for genvinding af varme lagret i frigivelsesluft.Cooling system (2,3,5,6,7) according to claim 4, wherein the at least one regenerating air heating unit (54) comprises a heat exchanger (54a, 54b, 54c) for recovering heat stored in release air. 6. Kølesystem (2,3,5,6,7) ifølge krav 4 eller 5, hvor den mindst ene regenereringsluftopvarmningsenhed (54) omfatter mindst en regenereringsluftvarmeveksler (54) til anbringelse på en eller flere udtagsluftstrømningsveje (12,22) for afgivelsesluft fra en spraytørrer (10) og/eller en fluid bed-tørrer (20) .A cooling system (2,3,5,6,7) according to claim 4 or 5, wherein the at least one regenerating air heating unit (54) comprises at least one regenerating air heat exchanger (54) for application to one or more outlet air flow paths (12, 22) for supply air from a spray dryer (10) and / or a fluid bed dryer (20). 7. Kølesystem (2,3,5,6,7) ifølge krav 4 eller 5, hvor den mindst ene regenereringsluftopvarmningsenhed (54) omfatter en primær luftvarmeveksler (54a), der er placeret nedstrøms fra det roterende tørremiddelhjul (50) på et andet stykke (41b) af den primære luftstrømningsvej (41), der er udvidet med en supplerende regenereringsluftopvarmningsenhed, der er placeret på nævnte regenereringsluftstrømningsvej (53)A cooling system (2,3,5,6,7) according to claim 4 or 5, wherein the at least one regenerating air heating unit (54) comprises a primary air heat exchanger (54a) located downstream of the rotary desiccant wheel (50) on another piece (41b) of the primary air flow path (41) extended by a supplementary regeneration air heating unit located on said regeneration air flow path (53) P81700245DK00 mellem varmeveksleren (54a) og det roterende tørremiddelhjul (50).P81700245DK00 between the heat exchanger (54a) and the rotary desiccant wheel (50). 8. Kølesystem (1,2,3,4,5,6,7) ifølge et hvilket som helst af de foregående krav, endvidere omfattende en sekundær luftaffugter (60), fortrinsvis en tørremiddelaffugter, og mest foretrukket et roterende tørremiddelhjul, der er anbragt på den sekundære luftstrømningsvej (42a,42b) opstrøms (42a) fra den indirekte fordampningskøler (40).A cooling system (1,2,3,4,5,6,7) according to any one of the preceding claims, further comprising a secondary air dehumidifier (60), preferably a desiccant dehumidifier, and most preferably a rotary desiccant wheel which is located on the secondary air flow path (42a, 42b) upstream (42a) from the indirect evaporative cooler (40). 9. Kølesystem (4,6,7) ifølge krav 8, hvor den sekundære luftaffugter er et roterende tørremiddelhjul (60), der er anbragt på den sekundære luftstrømningsvej (42a,42b) opstrøms fra den indirekte fordampningskøler (40), hvor det roterende tørremiddelhjul (60) omfatter et procesafsnit (61) og et regenereringsafsnit (62), hvor den sekundære luftstrømningsvej (42a,42b) gennemstrømmer det roterende tørremiddelhjul (60) ved procesafsnittet (61); hvilket kølesystem endvidere omfatter mindst en sekundær luftopvarmningsenhed (64) til opvarmning af indtagsluft til opnåelse af opvarmet regenereringsluft, der kan føres til det roterende tørremiddelhjuls (60) regenereringsafsnit (62), ad en regenereringsluftstrømningsvej (63), og mindst en luftbevægelsesenhed til at bevæge indtagsluft og opvarmet regenereringsluft ad nævnte regenereringsluftstrømningsvej (63).The cooling system (4,6,7) according to claim 8, wherein the secondary air dehumidifier is a rotary desiccant wheel (60) disposed on the secondary air flow path (42a, 42b) upstream from the indirect evaporative cooler (40), wherein the rotary desiccant wheels (60) comprise a process section (61) and a regeneration section (62), wherein the secondary air flow path (42a, 42b) flows through the rotary desiccant wheel (60) at the process section (61); the cooling system further comprising at least one secondary air heating unit (64) for heating intake air to obtain heated regeneration air which can be fed to the regeneration section (62) of the rotary desiccant wheel (60), along a regeneration air flow path (63), and at least one air movement unit intake air and heated regeneration air along said regeneration air flow path (63). 10. Kølesystem (4,5,6,7) ifølge krav 9, hvor den mindst ene sekundære luftopvarmningsenhed (64) omfatter en varmeveksler (54a,54b,54c) for genvinding af varme lagret i frigivelsesluft.The cooling system (4,5,6,7) according to claim 9, wherein the at least one secondary air heating unit (64) comprises a heat exchanger (54a, 54b, 54c) for recovering heat stored in release air. P81700245DK00P81700245DK00 11. Kølesystem (4,5,6,7) ifølge krav 9 eller 10, hvor den mindst ene sekundære luftopvarmningsenhed (64) omfatter mindst en sekundær luftvarmeveksler (54b,54c) til anbringelse på en eller flere udtagsluftstrømningsveje (12,22) for afgivelsesluft fra en spraytørrer (10) og/eller en fluid bed-tørrer (20) .A cooling system (4,5,6,7) according to claim 9 or 10, wherein the at least one secondary air heating unit (64) comprises at least one secondary air heat exchanger (54b, 54c) for mounting on one or more outlet air flow paths (12, 22) for discharge air from a spray dryer (10) and / or a fluid bed dryer (20). 12. Kølesystem (4,5,6,7) ifølge et hvilket som helst af kravene 9 til 11, hvor den sekundære luftvarmeveksler (64) og den primære luftvarmeveksler (54a) er en enhed, hvori nævnte primære luftstrømningsvej (41b) og regenereringsluftstrømningsvej (63) krydser og varmeveksler, således at primær luft afkøles, mens regenereringsluft opvarmes, hvorved den indirekte fordampningskølers (40) kølekapacitet forøges.A cooling system (4,5,6,7) according to any one of claims 9 to 11, wherein the secondary air heat exchanger (64) and the primary air heat exchanger (54a) are a unit wherein said primary air flow path (41b) and regeneration air flow path (63) crosses and heat exchanger so that primary air is cooled while regenerating air is heated, thereby increasing the cooling capacity of the indirect evaporative cooler (40). 13. Kølesystem (2,3,4,5,6,7) ifølge et hvilket som helst af kravene 9 til 12, hvor den mindst ene regenereringsluftopvarmningsenhed (54) og den mindst ene sekundære luftopvarmningsenhed (64) kombineret regenereringsluft- og luftopvarmningsenhed, og hvor luftstrømningsveje til regenereringsluft og/eller den sekundære luftstrømningsvej (42) først deles fra hinanden efter passage af den kombinerede regenereringsluft- og sekundære luftopvarmningsenhed.A cooling system (2,3,4,5,6,7) according to any one of claims 9 to 12, wherein the at least one regenerating air heating unit (54) and the at least one secondary air heating unit (64) combine regenerating air and air heating unit, and wherein air flow paths for regeneration air and / or the secondary air flow path (42) are first separated from each other after passage of the combined regeneration air and secondary air heating unit. danner en sekundær nævnte (53,63)forming a secondary one (53.63) 14. Kølesystem (2,3,4,5,6,7) ifølge et hvilket som helst af kravene 3 til 8, endvidere omfattende alene én tørremiddelaffugter, hvilken tørremiddelaffugter har tilstrækkelig kapacitet til at producere tør luft til at forsyne både behovet for primær luft og forA cooling system (2,3,4,5,6,7) according to any one of claims 3 to 8, further comprising only one desiccant dehumidifier, which desiccant dehumidifier has sufficient capacity to produce dry air to supply both the need for primary air and lining P81700245DK00 sekundær luft, og sekundære (42a,42b) fra hinanden efter tørremiddelaffugter.P81700245DK00 secondary air, and secondary (42a, 42b) apart after desiccant dehumidifier. hvor nævnte primære (41) og luftstrømningsveje først deles passage af den kun enewherein said primary (41) and air flow paths are first shared by the one only 15. Kølesystem (2,3,4,5,6,7) ifølge krav 14, hvor den kun ene tørremiddelaffugter er et roterende tørremiddelhjul for tilførsel af tør luft til en spraytørrer (10) ad en spraytørrertørreluftstrømningsvej (11), og hvor den primære (41) og den sekundære (42a,42b) luftstrømningsvej er i fluidforbindelse med nævnte spraytørrertørreluftstrømningsvej (11).A cooling system (2,3,4,5,6,7) according to claim 14, wherein the only one desiccant dehumidifier is a rotary desiccant wheel for supplying dry air to a spray drier (10) along a spray drier air flow path (11) and the primary (41) and the secondary (42a, 42b) air flow paths are in fluid communication with said spray dryer dryer air flow path (11). 16. Fluid bed-tørrer (20) (1,2,3,4,5,6,7) ifølge kravene 1 til 15.A fluid bed dryer (20) (1,2,3,4,5,6,7) according to claims 1 to 15. omfattende et hvilket et kølesystem som helst afcomprising any cooling system of any kind 17. Indretning omfattende en spraytørrer (10) og en fluid bed-tørrer (20), der er anbragt sekventielt for at muliggøre transport af et materiale, der skal tørres, fra spraytørreren (10) til fluid bed-tørreren (20), hvilken fluid bed-tørrer (20) omfatter et kølesystem (1,2,3,4,5,6,7) ifølge et hvilket som helst af kravene 1 til 15.Device comprising a spray dryer (10) and a fluid bed dryer (20) arranged sequentially to allow transport of a material to be dried from the spray dryer (10) to the fluid bed dryer (20), which fluid bed dryer (20) comprises a cooling system (1,2,3,4,5,6,7) according to any one of claims 1 to 15. 18. Anvendelse af en fluid bed-tørrer (20) ifølge krav 16 eller en indretning omfattende en spraytørrer (10) og en fluid bed-tørrer (20) ifølge krav 17 til tørring af et pulvermateriale.Use of a fluid bed dryer (20) according to claim 16 or a device comprising a spray dryer (10) and a fluid bed dryer (20) according to claim 17 for drying a powder material. 19. Fremgangsmåde til tilførsel af afkølet indtagsluft til en fluid bed-tørrer (20) til anvendelse som afkølet indtagsluft ved afkøling af et varmt19. A method of supplying cooled intake air to a fluid bed dryer (20) for use as cooled intake air in cooling a hot P81700245DK00 materiale, der skal tørres i fluid bed-tørreren (20); hvilken fremgangsmåde omfatter i et kølesystem ifølge et hvilket som helst af kravene 1 til 15 at tilføre primær luft ad en primær luftstrømningsvej (41) til en tør side af en indirekte fordampningskøler (40) og sekundær luft ad en sekundær luftstrømningsvej (42a, 42b) til en våd side af den samme indirekte fordampningskøler (40); at muliggøre, at den primære luft kan gennemstrømme den tørre side af den indirekte fordampningskøler (40), hvorved den bliver til afkølet indtagsluft, og at muliggøre, at den sekundære luft kan gennemstrømme den våde side af den indirekte fordampningskøler (40), hvorved den bliver til afkølet og fugtig sekundær luft; og at tilføre den afkølede indtagsluft til fluid bed-tørreren (20) via en fluid bed-tørrer-indtagsluftstrømningsvej (21), der forbinder den tørre side af den indirekte fordampningskøler (40) med fluid bed-tørreren (20).P81700245DK00 material to be dried in the fluid bed dryer (20); any method comprising, in a cooling system according to any one of claims 1 to 15, supplying primary air along a primary air flow path (41) to a dry side of an indirect evaporative cooler (40) and secondary air through a secondary air flow path (42a, 42b) to a wet side of the same indirect evaporative cooler (40); enabling the primary air to flow through the dry side of the indirect evaporative cooler (40), thereby generating cooled intake air, and allowing the secondary air to flow through the wet side of the indirect evaporative cooler (40), turns into cooled and moist secondary air; and supplying the cooled intake air to the fluid bed dryer (20) via a fluid bed dryer intake air flow path (21) connecting the dry side of the indirect evaporative cooler (40) to the fluid bed dryer (20). P81700245DK00P81700245DK00 OISLAND COCO 1/71.7
DKPA201500373A 2015-07-01 2015-07-01 A cooling system and a method of supplying cooled intake air to a fluid bed dryer DK179273B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DKPA201500373A DK179273B1 (en) 2015-07-01 2015-07-01 A cooling system and a method of supplying cooled intake air to a fluid bed dryer
PCT/DK2016/050231 WO2017000967A1 (en) 2015-07-01 2016-06-30 A cooling system and a method of cooling dry intake air to drying systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DKPA201500373A DK179273B1 (en) 2015-07-01 2015-07-01 A cooling system and a method of supplying cooled intake air to a fluid bed dryer

Publications (2)

Publication Number Publication Date
DK201500373A1 DK201500373A1 (en) 2017-01-16
DK179273B1 true DK179273B1 (en) 2018-03-26

Family

ID=57607901

Family Applications (1)

Application Number Title Priority Date Filing Date
DKPA201500373A DK179273B1 (en) 2015-07-01 2015-07-01 A cooling system and a method of supplying cooled intake air to a fluid bed dryer

Country Status (2)

Country Link
DK (1) DK179273B1 (en)
WO (1) WO2017000967A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4910971A (en) * 1988-02-05 1990-03-27 Hydro Thermal Engineering Pty. Ltd. Indirect air conditioning system
WO1995014644A1 (en) * 1993-11-23 1995-06-01 Apv Anhydro A/S A process for production of ceramic powders by spray drying
US5890372A (en) * 1996-02-16 1999-04-06 Novelaire Technologies, L.L.C. Air conditioning system for cooling warm moisture-laden air
US6018953A (en) * 1996-02-12 2000-02-01 Novelaire Technologies, L.L.C. Air conditioning system having indirect evaporative cooler
US20080230051A1 (en) * 2005-09-30 2008-09-25 Niro A/S Apparatus And A Process For Drying High Carbohydrate Content Liquids

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1317277A (en) * 1961-12-27 1963-02-08 Societe D'etudes, De Recherches Et D'applications Pour L'industrie Chimique Dite <<S. E. R. A. P. I. C.>> Improvements to drying and cooling by fluidization processes
NL1026096C2 (en) * 2004-05-03 2005-11-07 Statiqcooling B V Enthalpy exchanger and method for exchanging enthalpy between two media by means of such an enthalpy exchanger.

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4910971A (en) * 1988-02-05 1990-03-27 Hydro Thermal Engineering Pty. Ltd. Indirect air conditioning system
WO1995014644A1 (en) * 1993-11-23 1995-06-01 Apv Anhydro A/S A process for production of ceramic powders by spray drying
US6018953A (en) * 1996-02-12 2000-02-01 Novelaire Technologies, L.L.C. Air conditioning system having indirect evaporative cooler
US5890372A (en) * 1996-02-16 1999-04-06 Novelaire Technologies, L.L.C. Air conditioning system for cooling warm moisture-laden air
US20080230051A1 (en) * 2005-09-30 2008-09-25 Niro A/S Apparatus And A Process For Drying High Carbohydrate Content Liquids

Also Published As

Publication number Publication date
DK201500373A1 (en) 2017-01-16
WO2017000967A1 (en) 2017-01-05

Similar Documents

Publication Publication Date Title
US7305849B2 (en) Sorptive heat exchanger and related cooled sorption process
US9885486B2 (en) Heat pump humidifier and dehumidifier system and method
CN103075770B (en) Rotating wheel dehumidification device utilizing indoor exhaust evaporation cooling and use method of rotating wheel dehumidification device
CN107003078B (en) Dehumidification system and dehumidification method
CN201168542Y (en) Apparatus for continuously preparing low dew point low temperature drying air
JP2017517395A5 (en)
US9303885B1 (en) Desiccant dehumidification system and method
WO2007141901A1 (en) Humidity controller
JP2011512507A (en) Refrigerant desiccant refrigerant dehumidifier with enhanced energy recovery
CN110088549B (en) Drying system with improved energy efficiency and capacity control
CZ308655B6 (en) Compact device for obtaining water from the air
WO2018109990A1 (en) Drying device for coating
JP5890873B2 (en) Outside air treatment equipment using desiccant rotor
DK179273B1 (en) A cooling system and a method of supplying cooled intake air to a fluid bed dryer
JP2010002124A (en) Dehumidifying/reheating air-conditioning device
US10168057B2 (en) Method and apparatus for controlling moisture
JP2008020139A (en) Air conditioning system without refrigerating machine
US11608997B1 (en) Dual-wheel HVAC system and method having improved dew point control
JP6826853B2 (en) Outside air processing equipment
US11333371B1 (en) Dual-wheel HVAC system and method having improved dew point control
EP3271659A1 (en) A cooling system, a cooling unit, and a method of cooling intake-air to an air-conditioned building space
DK201500357A1 (en) A cooling system, a cooling unit, and a method of cooling intake air to an air conditioned building space

Legal Events

Date Code Title Description
PBP Patent lapsed

Effective date: 20190701