SE1850903A1 - Module for treating air, method for treating air, and related systems - Google Patents

Module for treating air, method for treating air, and related systems

Info

Publication number
SE1850903A1
SE1850903A1 SE1850903A SE1850903A SE1850903A1 SE 1850903 A1 SE1850903 A1 SE 1850903A1 SE 1850903 A SE1850903 A SE 1850903A SE 1850903 A SE1850903 A SE 1850903A SE 1850903 A1 SE1850903 A1 SE 1850903A1
Authority
SE
Sweden
Prior art keywords
air
module
flowrate
treatment unit
arrangement
Prior art date
Application number
SE1850903A
Other languages
Swedish (sv)
Other versions
SE543981C2 (en
Inventor
Anders Edström
Fredrik Edström
Mohamad Omar Mansour
Viktor Kjellberg
Original Assignee
Sally R Ab
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 Sally R Ab filed Critical Sally R Ab
Priority to SE1850903A priority Critical patent/SE543981C2/en
Priority to PCT/EP2019/068122 priority patent/WO2020011672A1/en
Publication of SE1850903A1 publication Critical patent/SE1850903A1/en
Publication of SE543981C2 publication Critical patent/SE543981C2/en

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F8/00Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying
    • F24F8/10Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying by separation, e.g. by filtering
    • F24F8/15Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying by separation, e.g. by filtering by chemical means
    • F24F8/167Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying by separation, e.g. by filtering by chemical means using catalytic reactions
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00Control or safety arrangements
    • F24F11/70Control systems characterised by their outputs; Constructional details thereof
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/74General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86Catalytic processes
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F12/00Use of energy recovery systems in air conditioning, ventilation or screening
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00Control inputs relating to air properties
    • F24F2110/10Temperature
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00Control inputs relating to air properties
    • F24F2110/20Humidity
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00Control inputs relating to air properties
    • F24F2110/50Air quality properties
    • F24F2110/64Airborne particle content
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00Control inputs relating to air properties
    • F24F2110/50Air quality properties
    • F24F2110/65Concentration of specific substances or contaminants
    • F24F2110/66Volatile organic compounds [VOC]
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00Control inputs relating to air properties
    • F24F2110/50Air quality properties
    • F24F2110/65Concentration of specific substances or contaminants
    • F24F2110/70Carbon dioxide
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F7/00Ventilation
    • F24F7/04Ventilation with ducting systems, e.g. by double walls; with natural circulation
    • F24F7/06Ventilation with ducting systems, e.g. by double walls; with natural circulation with forced air circulation, e.g. by fan positioning of a ventilator in or against a conduit
    • F24F7/08Ventilation with ducting systems, e.g. by double walls; with natural circulation with forced air circulation, e.g. by fan positioning of a ventilator in or against a conduit with separate ducts for supplied and exhausted air with provisions for reversal of the input and output systems
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • General Chemical & Material Sciences (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)

Abstract

The present inventive concept relates to a module for treating air, wherein the module is configured to be used in conjunction with an air treatment unit comprising an inlet arrangement for an intake of a first flow of air and an outlet arrangement for a discharge of exhaust air from the air treatment unit, wherein the module comprises: a first inlet arranged for an intake of ambient air; a second inlet configured to be connectable to the outlet arrangement of the air treatment unit and arranged for an intake of the exhaust air; and a first outlet configured to be connectable to the inlet arrangement of the air treatment unit; wherein the module is configured to: provide an outflow from the module via the first outlet, wherein the outflow constitutes at least a portion of the first flow of air, by controlling a first flowrate of the ambient air via the first inlet and a second flowrate of the exhaust air via the second inlet based on at least one parameter associated with at least one of the ambient air and the exhaust air; and capture at least one impurity present in at least one of the intake of ambient air and the intake of exhaust air.

Description

MODULE FOR TREATING AIR, METHOD FOR TREATING AIR, AND RELATED SYSTEMS Technical field The inventive concept described herein generally relates to the field of air treatment, and in particular to a module for treating air, and related methods.
Background According to recent estimations, 1 in 8 deaths are linked with air pollution. Air pollutions are present both outdoors and indoors, and since people today tend to spend a large amount of their time indoors, controlling the indoor environment is therefore of vital importance.
The field of indoor climate and indoor air quality has numerous aspects which may be divided into aspects relating to comfort and aspects relating to health issues. In the context of this application, comfort climate refers to aspects of climate such as temperature, humidity, odour control, etc. Aspects of health climate on the other hand are closely related to air pollution control. Examples of air pollutions may include e.g. particulate matter, benzene, nitrogen dioxide, sulphur dioxide, carbon monoxide, benzo(a)pyrene, radon, ozone, and volatile organic compounds (VOC) e.g. including hydrocarbons (HC), formaldehyde, alcohols, etc.
In an indoor environment, air pollution origins for example, from humans, furniture, cooking, etc. To control the indoor air pollution levels, the indoor air is therefore commonly let outside and ambient, or outside, air is let inside. Outdoor air may however be for example too hot, cool, humid or polluted. Therefore, to achieve a comfortable and healthy climate, the outside air led inside may have to be cooled or heated depending on the temperature, humidity may have to be added or removed depending on the water content, outdoor air pollutions may have to be removed, etc.
To control the temperature and to add and/or remove water from the outdoor air, heat pumps, or any other cooling machine, can be used. For example, the outdoor air may be cooled to the desired dew point and then heated, in order to obtain a desired temperature and humidity level. However, for this to work the whole year around at a location having varying seasons, the size of the cooling machine must unfortunately be chosen based on the demands on the expected hottest and most humid day.
Furthermore, as mentioned above, if the outside air is too dry, a humidifier must be used to control the humidity and/or if the outside air is polluted, air purifiers must be used to control the air pollution inside. State of the art air purifiers commonly comprise ionizers, HEPA filters, activated carbon beds, ultra violet light, thermal oxidation and catalytic oxidation. However, all these systems add to the energy requirements and the investment bill.
Accordingly, controlling the indoor climate is energy intense, at least in part due to the fact that the expected hottest, coolest and most polluted day of the year sets the size for the constituents in the system. Moreover, these systems often operate at a full capacity even if the building’s occupancy is low. Hence both investment- and operating costs for climate control devices tend to be high.
In order to alleviate some of these drawbacks, solutions have been proposed to reduce the energy requirements and/or the size of the system. For example, heat exchangers can be used to transfer energy between the indoor and the outdoor air when ventilating. This may reduce the need for heating and/or cooling. Also, measuring the indoor carbon dioxide and air pollution levels can lead to a reduction in the ventilation need. If the flow is reduced, the energy needed for temperature, humidity and air pollution control can also be reduced. A system as mentioned above comprising a heat exchanger could be designed as follows: fresh air would usually pass through a coarse filter that removes dust, leaves and other particles with large diameters. After that, it passes through a heat exchanger, where heat is exchanged between air supplied to the building (house) and return air coming back. In this way, the desired supply air temperature is achieved with less energy expense.
Consequently, the operation of cooling and/or heating elements, which in some cases are integrated into the system or built separately as chillers and radiators, could be reduced. For example, having an outdoor temperature of -5°C would require spending some amount of energy through the heaters to reach the supply temperature of 20°C. By exchanging heat with the return air, which might be 24°C, the supply temperature could be elevated from -5 to 20°C with less energy from those heaters. Similarly, the return air would pass again through another course filter to protect the heat exchanger from dust, after which it is vented outside via the exhaust fan.
In order to increase the efficiency of the filtering capacity of the abovementioned system, catalyst technologies may be applied. According to the prior art, there are volatile organic compound (VOC) concentrators. These concentrators utilize a combination of adsorption and catalytic or thermal technologies to concentrate the VOCs for destruction in catalytic or thermal oxidisers. Systems comprising concentrators of this kind may be useful for VOC concentrations that are too high for a cost-effective use of sacrificial systems and too low for a cost-effective use of thermal or catalytic oxidisers. These systems are composed of either activated carbon or zeolite as the adsorbing media to remove the VOCs.
However, systems according to the prior art, such as systems comprising VOC concentrators described above, are associated with numerous problems and/or deficiencies. First, these systems are usually bulky, and are often too large to be fit into and/or connected to commercial and residential air handling units (AHUs).
Second, the prior art systems are associated with a relatively high cost. For example, a system comprising VOC concentrators with an efficiency of 5000 m3/h may cost approximately 15 000 - 30 000 Euros. For residential and commercial AHUs, this cost is often considered unfeasible. Furthermore, the operation of systems of this kind may include frequent refurbishments of the thermal oxidizer (depending on the VOC concentration to be concentrated) and a heating of the air to high temperature levels for the thermal oxidizer to catalyze the VOCs. Moreover, since the VOC concentrator comprises zeolite or carbon, the system may experience a considerable pressure drop. Consequently, the flow rates of fans need to be increased, leading to an increase of the overall system energy consumption. Furthermore, the cleaning of supply and/or exhaust air, which is required for systems of this kind, requires a relatively large piping construction. Apart from an increasing cost associated with this, the construction may increase the system complexity and volume, which is especially problematic in case the space is limited.
Hence, alternative solutions are of interest, which alleviate at least some of the above-mentioned problems, and are able to provide a more efficient system in terms of operation, cost, space and/or complexity.
Summary of the invention It is an object of the present inventive concept to mitigate, alleviate or eliminate one or more of the above-identified deficiencies in the art and disadvantages singly or in combination.
According to a first aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a module for treating air, wherein the module is configured to be used in conjunction with an air treatment unit comprising an inlet arrangement for an intake of a first flow of air and an outlet arrangement for a discharge of exhaust air from the air treatment unit, wherein the module comprises: a first inlet arranged for an intake of ambient air; a second inlet configured to be connectable to the outlet arrangement of the air treatment unit and arranged for an intake of the exhaust air; and a first outlet configured to be connectable to the inlet arrangement of the air treatment unit; wherein the module is configured to: provide an outflow from the module via the first outlet, wherein the outflow constitutes at least a portion of the first flow of air, by controlling a first flowrate of the ambient air via the first inlet and a second flowrate of the exhaust air via the second inlet based on at least one parameter associated with at least one of the ambient air and the exhaust air; and capture at least one impurity present in at least one of the intake of ambient air and the intake of exhaust air.
In general, the present inventive concept is based on the idea of providing a module for treating air being configured to control input from a number of sources of air and to provide air to an air treatment unit based on at least one parameter associated with at least one of the number of sources of air. Hereby, a more efficient and flexible treatment of air may be achieved.
A further advantage with the present inventive concept is the possibility to treat ambient air being provided to an enclosed environment.
The module of the present inventive concept is further advantageous in that the air provided by the module to the air treatment unit is selectively conveyed from a number of air sources either in full via the module or in part via the module and a bypass path, thus achieving an effective operation which may decrease energy usage and increase the lifespan of fans, recirculation valves, coolers, heaters, humidifiers, and dehumidifiers of the module and/or the air treatment unit.
The term ‘capture’ should in the context of the present disclosure be understood to comprise adsorbing and/or converting.
It is to be understood that the first and second inlet may structurally be combined into one and the same inlet by e.g. a Y-fitting, a tee-fitting, or the like.
The at least one impurity may comprise at least one of a volatile organic compound (VOC), such as aldehydes, formaldehydes or amines, a particle, such as PM2.5, PM10, and/or PM100, CO2, CO, and ammonia.
The general phrase "a parameter associated with a volume of air" may be interpreted as a parameter indicative of a condition of the volume of air.
The module may be configured to receive parameter data pertaining to the at least one parameter from at least one sensor. Such a sensor may be arranged in communication with air to be analyzed, e.g. air of interest with respect to the at least one parameter. Further, it may be preferable to arrange such a sensor upstream of a point of control, e.g. in the case of controlling a flow of air via an inlet valve based on a parameter determined via a sensor, the sensor may preferably be arranged upstream of the inlet valve such that a volume of air present at the location of the sensor at the time of sensing does not reach the inlet valve during a time period of determining whether to intake the volume of air and adjusting or setting the inlet valve based on the parameter data. Hereby, the module may be controlled proactively, rather than reactively, e.g. if it is determined that the exhaust air is too hot, it may be preferable if such air does not enter the module.
Below are disclosed some examples of possible parameters which may be determined. It is appreciated that some sensors may be capable of determining more than one parameter, and that other types of sensors may be specifically configured to determine a single parameter. Accordingly, the module may comprise a number of sensors configured to collect parameter data pertaining to the at least one parameter.
The at least one parameter may comprise an air temperature, a CO2 level, a CO level, a humidity level, and/or a volatile organic compound level.
The at least one parameter may comprise a particle concentration. In particular, the at least one parameter may comprise a particle concentration of a particular particle size group or several particular size groups, such as PM2.5, PM10, and/or PM100.
The module may further comprise an inlet valve arrangement arranged to control the first flowrate and the second flowrate. The inlet valve arrangement may comprise a first inlet valve arranged to control the first flow rate, and a second inlet valve arranged to control the second flow rate.
The module may further be configured to provide the outflow from the module via the first outlet by controlling the first flowrate of the ambient air via the first inlet and the second flowrate of the exhaust air via the second inlet based on a desired value pertaining to the at least one parameter. The desired value may be pre-set during installation of the module, and/or set by a user via a user interface configured to communicate with the module. The desired value may also be set based on historical desired values.
The at least one parameter may be further associated with the outflow from the module. Hereby, it may be possible to determine properties of air exiting the module. Such information may be utilized as feedback for controlling e.g. the first and second flowrates via the first and second inlets of the module.
The module may comprise a treatment arrangement configured to capture the at least one impurity.
According to a second aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a system comprising: the module according to the first aspect of the inventive concept; an air treatment unit comprising an inlet arrangement for an intake of a first flow of air and an outlet arrangement for a discharge of exhaust air from the air treatment unit; a bypass path arranged to bypass the module, and configured to convey the ambient air into the air treatment unit via the inlet arrangement; at least one sensor configured to determine the at least one parameter associated with at least one of the ambient air and the exhaust air; wherein the module is further configured to control an ambient air flowrate from the bypass path and an outflow flowrate from the first outlet of the module based on the at least one parameter associated with at least one of the ambient air and the outflow.
The bypass path may generally be configured to convey ambient air into the air treatment unit while preventing any contaminant in the ambient air from being captured by the module, i.e. the bypass path may convey ambient air into the air treatment unit wherein the ambient air is not treated by the module.
The module may further be configured to control the ambient air flowrate from the bypass path and the outflow flowrate from the first outlet of the module based on a desired value pertaining to the at least one parameter.
As is readily understood, controlling flowrates may comprise controlling ratios between the disclosed flowrates of air, the absolute values of the disclosed flowrates of air may, or both.
The at least one sensor may be arranged upstream of the first inlet of the module, upstream of the second inlet of the module, upstream of the inlet arrangement of the air treatment unit, and/or downstream of the first outlet of the module.
It is further envisioned that a pre-filter may be arranged upstream of the treatment arrangement of the module. The pre-filter may be configured to filter, capture, collect or remove high molecular weight (HMW) impurities, such as ethyl acetate, toluene, cyclohexane etc. Such impurities may be defined as impurities with a molecular weight over 80 g/mol. The pre-filter may thus decrease, or fully prevent, the amount of HMW impurities being captured by the treatment arrangement of the module. This is advantageous since HMW impurities may be difficult to release from the treatment arrangement, thus diminishing the effectivity and/or lifespan of the treatment arrangement. The pre-filter may be integral to the module, however it is also envisioned that the pre-filter may be arranged in the system according to the inventive concept, external to the module.
According to a third aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a method for treating air comprising the steps of: providing an air treatment unit comprising an inlet arrangement for an intake of a first flow of air and an outlet arrangement for a discharge of exhaust air from the air treatment unit; providing a module for treating air comprising a first inlet arranged for an intake of ambient air, a second inlet configured to be connectable to the outlet arrangement of the air treatment unit and arranged for an intake of the exhaust air, and a first outlet configured to be connectable to the inlet arrangement of the air treatment unit, wherein the module is configured to provide an outflow from the module via the first outlet, wherein the outflow constitutes at least a portion of the first flow of air; providing a bypass path arranged to bypass the module, wherein the bypass path is configured to convey the ambient air into the air treatment unit via the inlet arrangement; receiving parameter data pertaining to at least one parameter associated with the ambient air and the exhaust air; controlling a first flowrate of the ambient air via the first inlet and a second flowrate of the exhaust air via the second inlet based on the at least one parameter associated with at least one of the ambient air and the exhaust air; controlling an ambient air flowrate from the bypass path and an outflow flowrate from the first outlet of the module based on the at least one parameter associated with at least one of the ambient air and the outflow.
The step of controlling the first flowrate of the ambient air via the first inlet and a second flowrate of the exhaust air via the second inlet may be further based on a desired value pertaining to the at least one parameter.
The step of controlling an ambient air flowrate from the bypass path and an outflow flowrate from the first outlet of the module based on the at least one parameter associated with the at least one of the ambient air and the outflow may be further based on the desired value pertaining to the at least one parameter.
A feature described in relation to one aspect may also be incorporated in other aspects, and the advantage of the feature is applicable to all aspects in which it is incorporated.
Other objectives, features and advantages of the present inventive concept will appear from the following detailed disclosure, from the attached claims as well as from the drawings.
Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. Further, the use of terms "first", "second", and "third", and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. All references to "a/an/the [element, device, component, means, step, etc]" are to be interpreted openly as referring to at least one instance of said element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.
Brief description of the drawings The above, as well as additional objects, features and advantages of the present inventive concept, will be better understood through the following illustrative and non-limiting detailed description of different embodiments of the present inventive concept, with reference to the appended drawings, wherein: FIG. 1 schematically illustrates an example of a system according to the inventive concept; FIG. 2 schematically illustrates an example of a system according to the inventive concept; FIG. 3 schematically illustrates a module according to the inventive concept; FIG. 4 is a flowchart diagram of a method for treating air.
The figures are not necessarily to scale, and generally only show parts that are necessary in order to elucidate the inventive concept, wherein other parts may be omitted or merely suggested.
Detailed description The present disclosure relates to [technical field]. Initially, some terminology may be defined to provide clarification for the following disclosure.
FIG. 1 illustrates a system 100 comprising a module 102 for treating air, the module 102 being configured to be used in conjunction with an air treatment unit 104 comprising an inlet arrangement 106 for an intake of a first flow of air and an outlet arrangement 108 for a discharge of exhaust air from the air treatment unit 104.
The module comprises a first inlet 110 for an intake of ambient air 120, and a second inlet 112 configured to be connectable to the outlet arrangement 108 of the air treatment unit 104 and arranged for an intake of the exhaust air from the air treatment unit 104. The module further comprises a first outlet 114 configured to be connectable to the inlet arrangement 106 of the air treatment unit 104. It is to be understood that the module 102 may comprise further inlets and/or outlets, however for the sake of clarity such inlets and/or outlets are not illustrated in the figure.
The air treatment unit 104 may be connected to an enclosed environment 116, and may be suitable for managing the condition, or quality, of air in the enclosed environment 116. By enclosed environment may in some embodiments be understood as an environment such as a room or similar space in a building. Other examples of enclosed environment include compartment of vehicles. The air treatment unit 104 may comprise means for inducing, or creating, a flow of air or a circulation of air. Such means include for example fans or pumps of which many types are available, since these types of components are well known in the art they will however not be described in further detail. The ambient air 120 may be air present outside of e.g. a room or building, or more specifically air present outside of the closed environment 116.
If the air treatment unit 104 is equipped with means for inducing or creating a flow of air or a circulation of air, it may be advantageous to arrange the module 102 such that the second inlet 112 of the module 102 is receiving exhaust air from the air treatment unit 104 (as illustrated), i.e. downstream of the air treatment unit 104. Such an arrangement may work with, rather than against, the pressure or flow created by the air treatment unit 104. However, it may also be possible to arrange the module 102 such that the second inlet 112 receive air from the enclosed environment 116 before the air has reached the air treatment unit 104, i.e. arranging the second inlet 112 upstream of the air treatment unit 104. Further, it may be possible to arrange the module 102 such that the first inlet 110 receive air from the air treatment unit 104 before the air has reached the enclosed environment 116, i.e. arranging the first inlet 110 downstream of the air treatment unit 104.
In the illustrated example, the various inlets and outlets described in the previous sections are connected via paths configured to convey air. Examples of such paths include ducts and pipes providing fluid connection between the components of the system according to the present inventive concept. It should be noted that the illustrated paths are merely a schematic representation of one example of the inventive concept.
A bypass path 118 is arranged to bypass the module 102, and the bypass path 118 is configured to convey ambient air 120 into the air treatment unit 104 via the inlet arrangement 106. The bypass path 118 may be utilized to convey ambient air 120 into the air treatment unit 104 in case the ambient air 120 does not need to be treated in the module 102.
As can be seen, an outflow provided by the module 102 via the first outlet 114 is directed to the bypass path 118 via an outflow path 119, and the outflow may then enter the air treatment unit 104 via the inlet arrangement 106. Further, exhaust air is provided to the module from the outlet arrangement 108 via an exhaust air path 121. As will be seen in FIG. 2, other arrangements of paths are possible within the scope of the present inventive concept.
The present inventive concept provides for several possibilities in terms of air to be provided to the air treatment unit 104. In general, the module 102 may be configured to provide an outflow from the module 102 via the first outlet 114 by controlling a first flowrate of the ambient air 120 via the first inlet 110 and a second flowrate of the exhaust air via the second inlet 112 based on at least one parameter associated with at least one of the ambient air 120 and the exhaust air. In particular, any of the first flowrate of the ambient air 120 via the first inlet 110 and the second flowrate of the exhaust air via the second inlet 112 may be zero.
In general, the system 100 and the module 102 may utilize a number of algorithms in order to determine, based on at least one parameter associated with the exhaust air and the ambient air 120, a set of flowrates (e.g. ambient air flowrate via first inlet and/or bypass path, outflow flowrate, exhaust air flowrate) which achieves a set air quality (e.g. a desired value pertaining to the at least one parameter) with the least energy expensed. The module may thus, based on at least one of a temperature level, a humidity level, a CO2 level, a particulate matter level, a VOC level, a CO level, or the like, associated with at air flows in connection to the module or the system (such as e.g. the ambient air, the first flowrate, the second flowrate, the ambient air flowrate, the outflow flowrate, and/or air within the enclosed environment) preferably determined by at least one corresponding sensor, control said flowrates (e.g. ambient air flowrate via first inlet, i.e. first flowrate, and/or bypass path, outflow flowrate, the second flowrate). Further, the module and/or the system may be configured to control flow generating means of the air treatment unit based on the at least one parameter associated with at least one of the airflows or volumes of air described above. Such flow generating means of the air treatment unit may be arranged to direct air to and from the enclosed environment respectively.
For example, exhaust air having a low concentration of VOCs and a low temperature relative respective given desired values may require less energy to bring to the respective given desired values compared to ambient air having a high concentration of VOCs but a close to ideal temperature relative the same respective given desired values.
The module 102 may further be configured to control an ambient air flowrate from the bypass path 118 and an outflow flowrate from the first outlet 114 of the module 102 based on the at least one parameter associated with at least one of the ambient air 120 and the outflow from the first outlet 114. In particular, any of the ambient air flowrate from the bypass path 118 and the outflow flowrate from the first outlet 114 may be zero.
The system 100 may comprise at least one sensor. Here, three sensors 122, 124, 126 are illustrated. The system may advantageously comprise one or more sensors within the module 102, and it is to be understood that the illustrated sensors are merely examples of sensors and their respective locations. The sensor 122 may e.g. be configured to determine parameter data pertaining to the at least one parameter associated with exhaust air discharged by the air treatment unit 104 via the outlet arrangement 108. The sensor 124 may e.g. be configured to determine parameter data pertaining to the at least one parameter associated with outflow provided by the module 102 via the first outlet 114. The sensor 126 may e.g. be configured to determine parameter data pertaining to the at least one parameter associated with the ambient air 120.
Referring now to FIG. 2, a system 200 similar to the system described in conjunction with FIG. 1 is illustrated. The system 200 shares several features, functions and advantages with the system described in conjunction with FIG. 1 , and such features, functions and advantages will for the sake of brevity not be repeated in the following sections.
As can be seen, an outflow provided by the module 202 via the first outlet 214 is directed directly to the air treatment unit 204 via the inlet arrangement here comprising a first air treatment unit inlet 207 and a second air treatment unit inlet 209. More specifically, the outflow provided by the module 202 via the first outlet 214 is directed directly to the air treatment unit 204 via the first air treatment unit inlet 207.
Further, exhaust air is provided to the module 202 from the outlet arrangement via the second inlet 212. Here, the outlet arrangement comprises a first air treatment unit outlet 211 and a second air treatment unit outlet 213. More specifically, the exhaust air is provided by the air treatment unit 204 via the first air treatment unit outlet 211. Exhaust air from the air treatment unit 204 which is not to be provided to the module 204 is discharged from the air treatment unit 204 via the second air treatment unit outlet 213.
It may also be noted that ambient air 220 is provided to the module 202 and the air treatment unit 204 respectively via separate paths. However, the function of the system 200 is similar to the system described in conjunction with FIG. 1 in that the module 202 may control various flowrates in order to achieve an energy efficient treatment of air to be provided to the enclosed environment 216.
An example of a module 302 according to the inventive concept will now be described with reference to FIG. 3. The module 302 comprises a first module inlet 303 arranged for an intake of a first flow of air 305 into the module 302, a first module outlet 307 arranged for a discharge of a second flow of air 309 from the module 302, a treatment arrangement 311 configured to capture at least one impurity present in the first flow of air 305, and a catalyst 313. The module here also further comprises a heater 315 configured to increase a temperature of air within the module 302, and a main flow generating device 317 configured to, in a cleaning mode, generate or facilitate the intake of the first flow of air 305 via the first module inlet 303 and the discharge of the second flow of air 307 via the first outlet 309.
The module may be configured to, in a cleaning mode, capture the at least one impurity present in the first flow of air via the treatment arrangement by providing the intake of the first flow of air and the discharge of the second flow of air; and in a regeneration mode, cease the intake of the first flow of air and the discharge of the second flow of air, increase a temperature of air within the module such that the at least one impurity captured by first treatment arrangement is released from the treatment arrangement, and catalyze a reaction of the released at least one impurity via the catalyst.
It may be noted that the module 302 is here illustrated having a first inlet 392 arranged for an intake of ambient air and a second inlet 394 configured to be connectable to an outlet arrangement of an air treatment unit (not shown) and arranged for an intake of exhaust air, wherein the first inlet 392 and the second inlet 394 are joined such that air from either of the first inlet 392 and the second inlet 394 may enter the module 302 via the first module inlet 303. The first inlet 392 and the second inlet 394 may be controlled via respective valves (not shown).
The module is divided into a main chamber 321 and a catalyst chamber 323. A flow generating device 319 is configured to, in the regeneration mode, generate a circulation of air within the module 302 from the catalyst chamber 323 to the main chamber 321 and back to the catalyst chamber 323 via a first passage 325 and a second passage 327. The first passage 325 and the second passage 327 may comprise an opening, a valve, or the like. In particular, the flow generating device 319 may be configured to, in the regeneration mode generate a circulation of air within the module 302 from the treatment arrangement 311 to the catalyst 313 via the first passage 325 and the second passage 327.
The module here further comprises a second module inlet 329 arranged for an intake of a third flow of air 331 into the module 302, and a second module outlet 333 arranged for a discharge of a fourth flow of air 335 from the module 302. The module 302 may thus be further configured to, in the regeneration mode, intake the third flow of air 331 and discharge the fourth flow of air 335. Hereby, regeneration of the treatment arrangement 311 in the regeneration mode may be facilitated.
It should be noted that the first flow of air 305, the second flow of air 309, the third flow of air 331 and the fourth flow of air 335, although all being depicted in the same figure, are not necessarily all present at the same time. For example, in the cleaning mode, only the first and second flow of air 305, 309 may be present, and in the regeneration mode, only the third and fourth flow of air 331 , 335 may be present.
The catalyst 313 may be configured to catalyze the at least one impurity at a temperature level of around 200 °C, such as between 150 °C and 250 °C.
The catalyst 313 may comprise or constitute (alternatively platinum coated) tin dioxide (SnO2). For example, the weight percent of the platinum in platinum coated tin dioxide may be in the range of 3-20 %. Particles of platinum-coated SnO2 may be fabricated in a size-range that is comparable to the pigments of paint products that can be brushed or sprayed onto portion(s) of a catalyst support. For example, the particles may have diameters in the order of 10 μm or less The catalyst 313 may comprise from 1-50 weight-%, based on the total weight of the catalyst 313, of a noble metal selected from the group consisting of platinum, palladium, gold, silver, and rhodium, which has been dispersed on from 50-99 weight-%, based on the total weight of the catalyst 313, of a metal oxide which possesses more than one stable oxidation state including at least tin oxide. The catalyst 313 may be particularly advantageous in case the noble metal is platinum and the metal oxide is tin oxide.
The catalyst 313 may comprise at least two precious metals with at least two different metal-oxides (for example, tin oxide plus one or more promoters) in a layered matrix. Precious metals can together comprise about 0.1-15 weight-% of the catalyst 313. The at least one promoter metal oxide may be chosen from metal oxide species from the transition series of the periodic table which are known to adsorb NOx species, namely, Fe2O3, NiO, Co2O3 and WO3. The composition of the promoter oxide(s) can vary from about 1-15 weight-% of the total catalyst material. Specifically, about 10 weight-% of the catalyst 313 may be Fe2O, NiO, Co-O, combined with about 1.25 weight-% of the catalyst 313 being platinum and ruthenium, with the balance being tin oxide.
For example, the catalyst 313 may comprise 70-99 weight-% of a metal oxide possessing more than one oxidation state (e.g. tin oxide), 0.1-15 weight-% of at least two precious metals of which one is Ru and the other is chosen from the group consisting of platinum (Pt), palladium (Pd), gold (Au), rhodium (Rh) and silver (Ag). The catalyst 313 may further comprise 1-15 weight-% of at least one promoter selected from the group consisting of Fe2O3, NiO, Co2O3 and WO3. It will be appreciated that the catalyst 313 as exemplified is associated with numerous advantages. For example, the relatively low light-off temperatures for CO and HC may enable an even more efficient catalytic conversion to CO2 at a lower cost.
As yet another alternative, the catalyst 313 may comprise 1-50 weight-% of a noble metal selected from the group consisiting of platinum (Pt), palladium (Pd), gold (Au), rhodium (Rh) and silver (Ag). The noble metal may have been dispersed on from about 50-99 weight-% of a metal oxide which possesses more than one stable oxidation state including at least tin oxide. The preparation of such a platinum-tin oxide-based catalyst may be accomplished by successive layering of the desired components, as follows: (1) a clean, dry substrate may be deaerated in a solution containing tin (II) 2-ethylhexanoate (SnEH, hereafter). The substrate is removed from the solution, and excess solution is removed from the substrate. Residual solution components are evaporated leaving an SnEH layer on the substrate which is thermally decomposed in air to tin oxide at 300°C. Several layers may be applied in the same manner to achieve the desired loading of tin oxide. (2) If desired, a promoter is added to the catalyst matrix in a similar fashion. For example, an iron oxide promoter may be added to an existing tin oxide-coated substrate by dearating in an iron nitrate solution, removing excess solution, evaporating the solvent, and finally thermally decomposing the nitrate to oxide. (3) Platinum may be added to the coated substrate as above using an aqueous solution of tetraamine platinum (II) dihydroxide or other platinum salt, with chloride-fee salts being preferred, and then thermally decomposing the salt. Instead of the thermal decomposition, a reductive decomposition can be used. For example, the catalyst coated substrate is heated in an atmosphere containing a reducing gas such as carbon monoxide or hydrogen to induce reduction of the platinum salt to platinum.
The active temperature of the catalyst 313 may be -10°C-500°C. For example, for conversion of formaldehyde (CH2O), the temperature of the catalyst 313 may be 0°C-25°C, or even somewhat lower. For hydrocarbons (HC), desorption may take place from an initial temperature of the catalyst 313 of about 35°C, and oxidation may be performed at an active temperature of the catalyst 313 at 80°C-120°C. The light-off temperature may be about 150°C for hexane (C6H14) and about 220°C for methane (CH4). A complete oxidation may occur at an active temperature of the catalyst 313 well below the auto-ignition temperature of each hydrocarbon, e.g. 309°C for pentane (C5H12) and 537°C for methane. As yet another example, the temperature of the catalyst 313 for oxidation of ethanol (C2H5OH) may be about 30°C, and complete oxidization may be achieved at 125°C. Analogously, for propanol (C3H7OH), the respective temperatures of the catalyst 313 may be 50°C and 120°C. For the oxidation of carbon monoxide (CO) and the reduction of nitrogen oxides (NOx), the active temperature of the catalyst 313 may be 200°C-500°C.
The catalyst 313 may be configured to capture, adsorb and/or absorb, and to convert, the at least one impurity. More specifically, the catalyst 313 may capture, adsorb and/or absorb the at least one impurity, and enable a reaction between the at least one impurity and an oxidizing agent, and desorb the oxidation products, thereby freeing sites for subsequent adsorptions and/or absorptions and reactions.
A method for treating air according to the inventive concept will now be described with reference to FIG. 4. For clarity and simplicity, the method will be described in terms of ‘steps’. It is emphasized that steps are not necessarily processes that are delimited in time or separate from each other, and more than one ‘step’ may be performed at the same time in a parallel fashion.
The method comprises a step 480 of providing an air treatment unit comprising an inlet arrangement for an intake of a first flow of air and an outlet arrangement for a discharge of exhaust air from the air treatment unit; a step 482 of providing a module for treating air comprising a first inlet arranged for an intake of ambient air, a second inlet configured to be connectable to the outlet arrangement of the air treatment unit and arranged for an intake of the exhaust air, and a first outlet configured to be connectable to the inlet arrangement of the air treatment unit, wherein the module is configured to provide an outflow from the module via the first outlet, wherein the outflow constitutes at least a portion of the first flow of air; a step 484 of providing a bypass path arranged to bypass the module, wherein the bypass path is configured to convey the ambient air into the air treatment unit via the inlet arrangement; a step 486 of receiving parameter data pertaining to at least one parameter associated with the ambient air and the exhaust air; a step 488 of controlling a first flowrate of the ambient air via the first inlet and a second flowrate of the exhaust air via the second inlet based on the at least one parameter associated with at least one of the ambient air and the exhaust air; and a step 490 of controlling an ambient air flowrate from the bypass path and an outflow flowrate from the first outlet of the module based on the at least one parameter associated with at least one of the ambient air and the outflow.
The inventive concept has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended patent claims.

Claims (13)

1. A module for treating air, wherein the module is configured to be used inconjunction with an air treatment unit comprising an in|et arrangement for an intakeof a first flow of air and an outlet arrangement for a discharge of exhaust air from theair treatment unit, wherein the module comprises: a first in|et arranged for an intake of ambient air; a second in|et configured to be connectable to the outlet arrangement ofthe air treatment unit and arranged for an intake of the exhaust air; and a first outlet configured to be connectable to the in|et arrangement of theair treatment unit; wherein the module is configured to: provide an outflow from the module via the first outlet, wherein the outflowconstitutes at least a portion of the first flow of air, by controlling a first flowrate of theambient air via the first in|et and a second flowrate of the exhaust air via the secondin|et based on at least one parameter associated with at least one of the ambient airand the exhaust air; and capture at least one impurity present in at least one of the intake ofambient air and the intake of exhaust air.
2. The module according to claim 1, wherein the module is configured toreceive parameter data pertaining to the at least one parameter from at least one SGFISOF.
3. The module according to claim 1 or 2, wherein the at least one parametercomprises at least one of an air temperature and an air humidity.
4. The module according to any one of the preceding claims, wherein the atleast one parameter comprises at least one of a C02 level, a volatile organiccompound level, and a particle concentration.
5. The module according to any one of the preceding claims, furthercomprising an in|et valve arrangement arranged to control the first flowrate and thesecond flowrate.
6. The module according to any one of the preceding claims, wherein themodule is further configured to provide the outflow from the module via the first outletby controlling the first flowrate of the ambient air via the first in|et and the secondflowrate of the exhaust air via the second in|et based on a desired value pertaining tothe at least one parameter.
7. The module according to any one of the preceding claims, wherein the atleast one parameter is further associated with the outflow from the module.
8. A system comprising: the module according to any one of claims 1 to 7; an air treatment unit comprising an in|et arrangement for an intake of afirst flow of air and an outlet arrangement for a discharge of exhaust air from the airtreatment unit; a bypass path arranged to bypass the module, and configured to conveythe ambient air into the air treatment unit via the in|et arrangement; at least one sensor configured to determine the at least one parameterassociated with at least one of the ambient air and the exhaust air; wherein the module is further configured to control an ambient air flowratefrom the bypass path and an outflow flowrate from the first outlet of the modulebased on the at least one parameter associated with at least one of the ambient airand the outflow.
9. The system according to claim 8, wherein the module is further configuredto control the ambient air flowrate from the bypass path and the outflow flowrate fromthe first outlet of the module based on a desired value pertaining to the at least one parameter.
10. The system according to claim 8 or 9, wherein the at least one sensor isarranged upstream of the first in|et of the module, upstream of the second in|et of themodule, upstream of the in|et arrangement of the air treatment unit, and/ordownstream of the first outlet of the module.
11.A method for treating air comprising the steps of: providing an air treatment unit comprising an in|et arrangement for anintake of a first flow of air and an outlet arrangement for a discharge of exhaust airfrom the air treatment unit; providing a module for treating air comprising a first in|et arranged for anintake of ambient air, a second in|et configured to be connectable to the outletarrangement of the air treatment unit and arranged for an intake of the exhaust air,and a first outlet configured to be connectable to the in|et arrangement of the airtreatment unit, wherein the module is configured to provide an outflow from themodule via the first outlet, wherein the outflow constitutes at least a portion of thefirst flow of air; providing a bypass path arranged to bypass the module, wherein thebypass path is configured to convey the ambient air into the air treatment unit via thein|et arrangement; receiving parameter data pertaining to at least one parameter associatedwith the ambient air and the exhaust air; controlling a first flowrate of the ambient air via the first in|et and a secondflowrate of the exhaust air via the second in|et based on the at least one parameterassociated with at least one of the ambient air and the exhaust air; controlling an ambient air flowrate from the bypass path and an outflowflowrate from the first outlet of the module based on the at least one parameterassociated with at least one of the ambient air and the outflow.
12. The method according to claim 11, wherein the step of controlling the firstflowrate of the ambient air via the first in|et and a second flowrate of the exhaust airvia the second in|et is further based on a desired value pertaining to the at least one parameter.
13. The method according to claim 12, wherein the step of controlling theambient air flowrate from the bypass path and an outflow flowrate from the first outletof the module based on the at least one parameter associated with the at least oneof the ambient air and the outflow is further based on the desired value pertaining tothe at least one parameter.
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