Drying Apparatus
The present invention relates to drying apparatus for providing drying air to an interior of a building.
With increasingly unpredictable weather conditions and heavy spells of rain becoming more common, flooding of residential and commercial buildings is becoming an increasing problem. This may, for example, be due to rainwater penetrating a building directly, or due to flood water caused by flooding of nearby rivers and the like. Flooding or water damage may also occur when there has been a fire in a building and fire extinguishers, hoses, or sprinkler systems are employed to extinguish the fire.
When a building becomes flooded or water damaged, water is absorbed by the various surfaces of the building, and thus even after the flood water has subsided, the interior of the building remains damp. Until the interior of the building has been dried, it cannot usually be reoccupied.
It is therefore desirable to dry the interior of a damp building as quickly as possible so that it can be reoccupied, whilst at the same time minimising the concentration of heat at particular points in the interior of the building to avoid shrinkage or other undesirable effects.
According to a first aspect of the present invention, there is provided drying apparatus for providing drying air to an interior of a building, the drying apparatus being beatable in an interior of a building to be dried and comprising an air inlet arrangement for receiving moist air from the interior of the building, a heating arrangement for heating a proportion of the moist air from the air inlet arrangement to provide heated air, a dehumidifying arrangement for removing moisture from a proportion of the moist air from the air inlet arrangement to provide dehumidified air, and a drying air outlet for supplying the heated air and the dehumidified air to the interior of the building to dry the interior of the building.
The apparatus is preferably portable and may be dimensioned such that it can pass through a standard doorway in a domestic building. The apparatus may have exterior dimensions of approximately 1.4 to 1.7 metres in length, approximately 0.4 to 0.8 metres in width, and approximately 0.7 to 1.1 metres in height. Preferably, the exterior dimensions of the apparatus are approximately 1.5 metres in length, approximately 0.65 metres in width, and approximately 0.9 metres in height.
The air inlet arrangement may comprise a first air inlet for conveying moist air from the interior of the building to the heating arrangement, and may comprise a second air inlet for conveying moist air from the interior of the building to the dehumidifying arrangement.
The apparatus may comprise a control arrangement which may be arranged to control the heating arrangement to heat the moist air from the first air inlet to a predetermined first temperature. The control arrangement may be arranged to control the heating arrangement to heat the moist air from the first air inlet to provide heated air at a predetermined first temperature of between approximately 350°C and 55O0C, and more preferably between approximately 400°C and 5000C.
The apparatus may comprise a first subsidiary air inlet for conveying moist air from the interior of the building to the heating arrangement, and for mixing said moist air with the air heated to the predetermined first temperature to reduce the temperature of the heated air. The control arrangement may be arranged to control the volume of moist air conveyed through the first subsidiary air inlet to reduce the temperature of the heated air to a predetermined second temperature. The control arrangement may be arranged to control the volume of moist air conveyed through the first subsidiary air inlet to reduce the temperature of the heated air to a predetermined second temperature between approximately 12O0C and 160"C1 and more preferably to a predetermined second temperature of approximately 1400C.
The apparatus may comprise a second subsidiary air inlet for conveying moist air from the interior of the building and for mixing said moist air with the air at the predetermined second temperature.
The heating arrangement may comprise a burner, which may be a gas fired burner. The gas fired burner may be a liquefied natural gas fired burner, for example a propane fired burner. The apparatus may be arranged such that the moist air from the first air inlet is conveyed to the burner to provide combustion air.
The burner may include a combustion chamber. The combustion chamber may include side walls and a lower wall which may define an interior of the combustion chamber. An upper end of the combustion chamber may be open to enable hot combustion gases to escape upwardly from the combustion chamber. A burner head may project into the combustion chamber, and may project generally horizontally into the combustion chamber, preferably through a side wall thereof. The combustion chamber may have interior dimensions in the order of approximately 250mm in width, 250mm in length, and 600mm in height.
The heating arrangement may be arranged to operate in a high power mode in which it may be arranged to provide heat energy of up to 5OkW to heat the moist air received from the first air inlet. Preferably, the heating arrangement is arranged to provide heat energy of approximately 35kW when operating in the high power mode. The heating arrangement may be arranged to operate in a low power mode in which it may be arranged to provide heat energy of approximately 15kW to heat the moist air received from the first air inlet.
The apparatus may comprise a heat exchanger to extract heat energy from the air at the predetermined second temperature, and the apparatus may be arranged to convey the air at the predetermined second temperature through a heat extraction portion of the heat exchanger to enable the
extraction of heat energy from the air. The heat exchanger may be a rotary heat exchanger.
The apparatus may include an external air inlet for conveying moist air from the exterior of the building in which the apparatus is located through a heat recovery portion of the heat exchanger to recover heat therefrom and thereby increase the temperature of the external air to a drying temperature.
The apparatus may be arranged to increase the temperature of the exterior air to a drying temperature of between approximately 25°C and 65°C, and more preferably between approximately 30°C and 55°C.
The apparatus may include air movement means for conveying moist air from the exterior of the building through the external air inlet and subsequently through the heat recovery portion of the heat exchanger. The air movement means may be arranged to convey the heated air from the heat recovery portion into the interior of the building via the drying air outlet.
The apparatus may include an exhaust air outlet for removing cooled exhaust air from the heat extraction portion of the heat exchanger. An exhaust duct may be connected, in use, to the exhaust air outlet to convey the exhaust air to the exterior of the building in which the apparatus is located, in use.
The dehumidifying arrangement may comprise a desiccant wheel, which is preferably rotatable. The apparatus may divide the desiccant wheel into a dehumidifying section, in which moisture is absorbed from moist air by the desiccant wheel, and a regeneration section, in which moisture is removed from the desiccant wheel.
The apparatus may be arranged such that a proportion of the air from the second air inlet is mixed with heated air from the combustion chamber to provide heated air at the predetermined first temperature.
The apparatus may include air movement means for conveying moist air from the interior of the building in which the apparatus is located through
the second air inlet to the dehumidifying section of the desiccant wheel. Said air movement means may be arranged to convey dehumidified air from the dehumidifying section to the interior of the building, and is preferably arranged to convey the dehumidified air to the interior of the building via the drying air outlet.
The apparatus is preferably arranged such that the relative humidity of the moist air conveyed through the dehumidifying section into the interior of the building is between approximately 10% and 50%, more preferably between approximately 25% and 50%, and preferably approximately 35%.
The apparatus may be arranged such that the heated air at the drying temperature and the dehumidified air are mixed to provide drying air prior to being conveyed into the interior of the building via the drying air outlet.
The apparatus may be arranged to convey a proportion heated air at the predetermined first temperature from the heating arrangement to the regeneration section of the desiccant wheel. The apparatus may be arranged to mix moist air from the second air inlet with the heated air at the predetermined first temperature to provide desiccant regeneration air, preferably at a predetermined desiccant regeneration temperature, for example at a predetermined desiccant regeneration temperature of approximately 140°C. The control arrangement may be arranged to control the volume of air from the second air inlet and the volume of heated air at the predetermined first temperature to provide air at the predetermined desiccant regeneration temperature.
The apparatus may include a desiccant regeneration air movement means for conveying the desiccant regeneration air through the regeneration section to remove moisture from the desiccant wheel. The desiccant regeneration air movement means may be arranged to convey a proportion of the heated air at the predetermined first temperature and a proportion of the moist air from the second air inlet to the regeneration section. The desiccant regeneration air movement means may be arranged to convey moist air from
the regeneration section to the exhaust air outlet and to the exterior of the building in which the apparatus is located, in use.
According to a second aspect of the present invention, there is provided a method of drying an interior of a building using drying apparatus according to the first aspect of the present invention, the method comprising conveying moist air from the interior of the building to the heating arrangement to heat the air, conveying moist air from the interior of the building to the dehumidifying arrangement to dehumidify the air, mixing the heated and dehumidified air to provide drying air, and conveying the drying air to the interior of the building to dry the interior of the building.
A preferred embodiment of the invention will now be described by way of example only and with reference to the accompanying drawings, in which:-
Fig. 1 is a diagrammatic perspective view from a first side of drying apparatus according to the invention;
Fig. 2 is a diagrammatic perspective view from a second side of drying apparatus according to the invention;
Fig. 3 is a schematic view of the drying apparatus of Figs. 1 and 2;
Fig. 4 is a first diagrammatic perspective view of the apparatus of Figs. 1 to 3 from the first side with exterior panels removed;
Fig. 5 is a second diagrammatic perspective view of the apparatus of Figs. 1 to 4 from the first side with exterior panels removed;
Fig. 6 is a first diagrammatic perspective view of the apparatus of Figs.
1 to 5 from the second side with exterior panels removed; and
Fig. 7 is a second diagrammatic perspective view of the apparatus of Figs. 1 to 6 from the second side with exterior panels removed.
Referring to the drawings, there is shown generally drying apparatus 10 for providing drying air to an interior of a building (not shown) to dry the building, for example following flooding or as a result of other water damage.
The apparatus 10 is located, in use, in the interior of the building to be dried and comprises an air inlet arrangement preferably in the form of first and second air inlets 12a, 12e for receiving moist air from the interior of the building in which the apparatus 10 is located, a heating arrangement 14 for heating the moist air from the first air inlet 12a to provide heated air, a dehumidifying arrangement 16 for removing moisture from the moist air from the second air inlet 12e to provide dehumidified air, and a drying air outlet 18 for supplying the heated air and the dehumidified air to the interior of the building to dry the interior of the building.
Referring in particular to Figs. 1 and 2, the apparatus 10 includes a plurality of exterior panels 20 which together define an interior region of the apparatus 10 in which the heating arrangement 14 and the dehumidifying arrangement 16 are located. The apparatus 10 is generally portable and includes wheels, for example in the form of castors, which enable the apparatus 10 to be easily manoeuvred. In a preferred embodiment, the exterior dimensions of the apparatus are approximately 1.5 metres long, approximately 0.65 metres wide and approximately 0.9 metres high. However, the apparatus 10 may have exterior dimensions of between approximately 1.4 and 1.7 metres long, approximately 0.4 and 0.8 metres wide and approximately 0.7 and 1.1 metres high. It is particularly important that the exterior dimensions of the apparatus 10 are such that it can pass through a standard doorway in a domestic building, thus enabling the apparatus 10 to be located inside a building to be dried, in use.
In more detail and referring in particular to Figs. 3 to 7, the heating arrangement 14 is located in a heating chamber 25 of the apparatus 10 and comprises a gas burner 22 which, in the preferred embodiment of the invention, is a propane fired burner. The burner 22 comprises a combustion
chamber 24 having side walls 26 and a lower wall 28 which together define an interior 30 of the combustion chamber 24. The combustion chamber 24 is mounted on a vertical support panel 32, and the burner 22 includes a burner head 34 which projects generally horizontally through the vertical support panel 32 and into the combustion chamber 24 through one of the side walls 26, which is provided with an appropriate cut out portion for receiving the burner head 34.
The combustion chamber 24 is open at an upper end thereof to enable heated air and combustion gases to escape upwardly from the interior 30 of the combustion chamber 24.
The combustion chamber 24 is designed to be compact relative to the overall dimensions of the apparatus 10, and according to a preferred embodiment of the invention, the combustion chamber has interior dimensions in the order of approximately 250 millimetres in width, 250 millimetres in length and 600 millimetres in height.
The burner 22 may operate in a high power mode or a low power mode, depending upon the particular heating requirements. In the high power mode, the burner 22 has an energy output of approximately 35 kW, although it may have an output of up to 50 kW. In the low power mode, the burner 22 has an energy output of approximately 15 kW.
The dehumidifying arrangement 16 comprises a desiccant wheel 36 which includes a standard desiccant material capable of absorbing moisture from moist air forced through the desiccant wheel 36. The apparatus 10 divides the desiccant wheel 36 into a dehumidifying section 38 through which moist air to be dehumidified, from the second air inlet 12e, is drawn and a regeneration section 40 through which heated regeneration air is drawn to evaporate moisture from the desiccant material and thereby regenerate the desiccant material so that it may again be used to absorb moisture from moist from the second air inlet 12e.
The desiccant wheel 36 is rotated continuously such that when desiccant material has absorbed moisture in the dehumidifying section 38, it is subsequently rotated into the regeneration section 40 where the moisture is removed by the heated regeneration air, before subsequently being rotated again into the dehumidifying section 38 where it absorbs moisture from the moist air conveyed from the second air inlet 12e. The construction and operation of such rotatable desiccant wheels is well known to those skilled in the art and accordingly no further description will be provided here.
The apparatus 10 further includes a rotary heat exchanger 42 for extracting heat energy from the air heated by the burner 22. Again, the heat exchanger 42 is of conventional construction and will be well understood by those skilled in the art. The provision of the heat exchanger 42 to extract heat energy from the heated air is necessary since the air heated by the burner 22 comprises noxious combustion gases which it is highly undesirable to supply directly to the interior of the building in which the apparatus 10 is located, in use.
As highlighted above, in order to dry the interior of the building in which the apparatus 10 is located as rapidly as possible, a constant flow of drying air, which comprises heated air and dehumidified air, is desirable. In order to provide heated air, moist air from the interior of the building in which the apparatus is located is conveyed by the first air inlet 12a to the burner 22. The moist air from the first air inlet 12a is heated in the interior 30 of the combustion chamber 24 and, upon exiting the combustion chamber 24 from the upper open end, is at a predetermined first temperature in the order of between approximately 400°C and 5000C. The burner 22 may in practice heat the air to a temperature in the order of 12000C, and a proportion of the air from the second air inlet 12e is therefore mixed with the heated air to reduce its temperature to the aforementioned predetermined first temperature.
In order to reduce the temperature of the air heated to the predetermined first temperature, the apparatus 10 includes a first subsidiary air inlet 12b through which moist air from the interior of the building is
conveyed and mixed with the air heated to the predetermined first temperature. The first subsidiary air inlet 12b is located towards an upper end of the heating chamber 23. By mixing the air heated to the predetermined first temperature with moist air from the interior of the building, the temperature of the heated air is reduced from the predetermined first temperature to a predetermined second temperature of approximately 1400C.
The apparatus 10 includes a heated air conduit 44 into which the heated air at the predetermined second temperature is conveyed from the heating chamber 23. An air flow control flap 46 is located in the conduit 44 and is adjustable to enable the volume of air conveyed from the heating chamber 23 to the conduit 44 to be varied.
The apparatus includes a second subsidiary air inlet 12c for conveying moist air from the interior of the building into the conduit 44 where it is mixed with the heated air at the predetermined second temperature. Adjustment of the air flow control flap 46 also enables the flow of air through the second subsidiary air inlet 12c to be controlled. This allows the temperature of the heated air to be controlled and varied as desired, although in the preferred embodiment the heated air transferred along the heated air conduit 44 is desirably at substantially the predetermined second temperature of approximately 140°C.
The heated air is conveyed along the heated air conduit 44 to the heat exchanger 42 where it is conveyed through a heat extraction portion 48 of the heat exchanger 42 to extract the heat energy from the heated air. The cooled exhaust air exiting from the heat extraction portion 48 of the heat exchanger
42 is subsequently conveyed to an exhaust air outlet 50. An exhaust duct (not shown) is connected to the exhaust air outlet 50 and leads to the exterior of the building in which the apparatus 10 is located to thereby convey the cooled air, which contains noxious combustion gases, to the outside of the building.
In order to recover the heat from the heat exchanger 42 and thereby provide heated air to the interior of the building in which the apparatus 10 is
located, the apparatus includes an external air inlet 12d through which external air from the exterior of the building is conveyed. The external air is conveyed to a heat recovery portion 52 of the heat exchanger 42 and is conveyed through the heat recovery portion 52 where its temperature is raised and the heat thus recovered from the heat exchanger 42. The temperature of the moist air is raised desirably to a drying temperature in the order of between 30DC and 55°C. The temperature of the external air may however be raised to a temperature anywhere between approximately 25°C and 65°C. The heated external air from the heat recovery portion 52 of the heat exchanger 42 is subsequently conveyed to the interior of the building through the drying air outlets 18.
In order to provide dehumidified air to the interior of the building in which the apparatus 10 is located, moist air is conveyed via the second air inlet 12e to the dehumidifying section 38 of the desiccant wheel 36. The moist air is drawn through the dehumidifying section 38 to reduce the relative humidity of the air to approximately 35%. The dehumidified air from the dehumidifying section 38 is then conveyed into the interior of the building in which the apparatus 10 is located through the drying air outlets 18.
The heating chamber 23 includes an aperture 54 and associated air flow control flap 56 which enable a proportion of the air heated to the predetermined first temperature of between 400°C and 500°C to be conveyed towards the regeneration section 40 of the desiccant wheel 36. Prior to reaching the regeneration section 40, the heated air is mixed with a proportion of the moist room air conveyed through the second air inlet 12e to thereby reduce the air temperature to a regeneration temperature in the order of approximately 14O0C. The regeneration air is conveyed through the regeneration section 40 of the desiccant wheel 36 thereby heating the desiccant material and evaporating the moisture absorbed by the desiccant material in the dehumidifying section 38. The moist air exiting from the regeneration section 40 is conveyed along a moist air duct 58 and subsequently through the exhaust air outlet 50 along the exhaust air duct and to the exterior of the building in which the apparatus 10 is located.
In order to convey the moist air from the interior of the building through the first air inlet 12a and the first and second subsidiary air inlets 12b, 12c, the apparatus 10 includes air movement means in the form of a fan 60. As best seen in Fig. 3, the fan 60 is also operable to draw heated air upwardly through the heating chamber 23, along the heated air conduit 44, through the heat extraction portion 48 of the heat exchanger 42 and subsequently through the exhaust air outlet 50, to the exterior of the building.
The apparatus includes a further air movement means in the form of a fan 62 which is operable to convey external air from outside the building through the external air inlet 12d, through the heat recovery portion 52 of the heat exchanger 42, and subsequently through the drying air outlets 18 into the interior of the building.
A further air movement means in the form of fan 64 is operable to convey moist air from the interior of the building through the second air inlet 12e, through the dehumidifying section 38 of the desiccant wheel 36 and subsequently into the interior of the building, again via the drying air outlets 18. As best seen in Figs. 5 and 6, the preferred embodiment of the apparatus 10 includes two air outlets 18. In this preferred embodiment, the fans 62 and 64 are preferably operable to mix the heated air and the dehumidified air together to provide drying air prior to conveying the drying air through the drying air outlet 18 into the interior of the building.
The apparatus includes a further air movement means in the form of a fan 66 which is operable to convey a proportion of the heated air at the predetermined first temperature through the aperture 54 from the heating chamber 23, and a proportion of the air from the second air inlet 12e to the regeneration section 40 of the desiccant wheel 36. The fan 66 subsequently conveys the moist air from the regeneration section 40 through the exhaust air outlet 50 and to the exterior of the building.
The apparatus 10 includes a plurality of temperature sensors, such as Platinum Resistance Thermometer (PRT) sensors (not shown), to monitor the temperature of the air at different positions in the apparatus 10 and inside the building being dried. The apparatus also includes a humidity sensor to monitor the humidity of the air inside the building being dried. These temperature sensors and humidity sensor are linked to a control arrangement 68 which is operable to switch the burner 22 between the high and low power operating modes, control the fans 60, 62, 64, 66, and control the air flow control flaps 46, 56 to maintain optimum air temperatures and air flow rates throughout the apparatus to provide drying air at substantially the desired predetermined drying temperature, relative humidity and desired volume flow rate. In the preferred embodiment of the apparatus, drying air is supplied from the drying air outlets 18 at a volume flow rate of approximately 2000 m3/hr.
Although not illustrated, in order to enable the drying air from the drying air outlet 18 to be distributed throughout the building in which the apparatus 10 is located, a suitable flexible duct may be connected to the drying air outlet 18, and this may extend throughout the building and include an appropriate number of apertures to enable the drying air to escape from the duct.
There is thus provided drying apparatus 10 for providing drying air to an interior of a building which enables the interior of the building to be dried rapidly and effectively. Due to the fact that the apparatus 10 is dimensioned so that it can be located within any domestic or commercial building, there is no risk of theft or vandalism as with conventional large scale apparatus which must remain outside the building. Furthermore, the combination of the heating arrangement 14 and the dehumidifying arrangement 16 enables the provision of drying air at an optimum temperature, relative humidity and flow rate to achieve rapid drying of the interior of the building without causing damage to the interior of the building.
Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that various modifications to the examples given may be made
without departing from the scope of the present invention. For example, any suitable heating arrangement 14 may be employed. The combustion chamber 24 may be of a different configuration. Any suitable dehumidifying arrangement 16 or heat exchanger 42 may be employed. The apparatus 10 may have a configuration other than that specifically illustrated in the accompanying drawings.
Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.