SE502635C2 - Methods and plant to increase the yield of an air drying process - Google Patents

Abstract

A method of increasing the yield of an air drying process involves delivering process air to a first process-air chamber (7) in an insulated housing (1) and having a defining wall which accommodates a rotating drying rotor (5). The process air is dehumidified and dried while exchanging moisture with hot regeneration air. The dried and heated process air is sucked into a second process-air chamber (8) which accommodates a high-pressure fan (18) provided with an electric motor (17), such that the process air passes and is heated by the electric motor prior to its delivery to the fan inlet. The pressurized process air of higher temperature is therewith delivered directly to a water-damaged layer or area. The invention also relates to an air drying apparatus which comprises an insulated housing (1) having two mutually delimited chambers (7, 8), of which the first chamber (7) accommodates a low-pressure fan (12) and the second chamber accommodates a high-pressure fan (18) provided with an electric motor (17) and operating in accordance with the method.

Description

502 655 dry, hot air under overpressure is introduced into the gap for the removal of moisture-laden air from the water-damaged area.

In this and other today practically applied procedures resp. systems, the dehumidifier sucks in air to be dried, after which the dry air is led via a hose to a high-pressure fan where it is pressurized. The pressurized dry air is pressed down into the insulation and after passage through the wet insulation, where the air takes up water, the air comes up into the room again where it is again sucked into the dehumidifier. Suitable dehumidifiers for use in methods of the type indicated are described in SE, C, 8804281-7 and its American counterpart US, A, 5,147,420 (Corroventa) and SE, C, 9102488-5 (Corroventa Dehumidification).

Optimal drying equipment should have the following characteristics: a) be easy to handle, b) be easy to install, c) have as few components as possible, d) have as low a price as possible, e) have a low noise level, f) emit dry air with as low a water content as possible, g) emit air with as low relative humidity as possible, h) emit as hot air as possible, i) have as low energy consumption as possible, and j) be easy to control, ie allow simple measurement of temperatures and air volumes.

No drying plant on the market today meets all these requirements. Known systems thus require a number of components such as dehumidifiers, high-pressure fans, hoses, pipes, hose clamps, etc. which make it difficult to handle and install these. It often happens that the operator at the place of use forgets to bring the components necessary for the function. Finished installations also usually take up a lot of space and take a long time to make. 502 635 A result of the large number of components is that the total price for the installation will be high.

Another problem is that the noise level for conventional dehumidifiers is high and for the high pressure fan very high. This means that the inconvenience to the people who live or live where the injury has occurred becomes very great. In some cases, there is a requirement that the sound level must not exceed a certain number of decibels, whereby this type of product cannot be used at all.

Furthermore, since the dry air from the dehumidifier to the turbine travels through hoses that are uninsulated, the air will be cooled, which also causes the relative humidity to increase. Furthermore, the energy of the high-pressure fan is largely supplied to the environment and not the dry air, which also contributes to a lower temperature and a higher relative humidity compared with what is possible and desirable. The cooling in hoses that occurs when using high-pressure fans according to currently established technology means that the high-pressure fan's energy is not fully utilized, which in practice leads to the drying time being extended 3-4 times due to the colder and humid air not being able to to carry away sufficient water from the moisture-damaged area.

The following factors are most important for enabling rapid drying of a water damage: l) The amount of air that travels through the moisture-damaged area.

The greater the amount of air, the faster the drying takes place. 2) The relative humidity and temperature of the dry air.

The lower the relative humidity and the higher the temperature, the greater the amount of water the air can remove. A high temperature also causes the moisture-damaged material to heat up, whereby the water vapor pressure in the pores increases and thus the water evaporation. Increased water evaporation gives a correspondingly shorter drying time.

Thus, in current technology and where the temperature of the dry air is, for example, 30-35 ° C, the water vapor pressure in the pores becomes about 35 mm Hg. If the temperature were to increase 502 635 to 60 to 80 ° C, the water vapor pressure would be about 230 mm Hg, ie about 7 times higher, which would offer a drying time that is 1/7 of what can be achieved with conventional technology. 3) With established technology, not all available energy is utilized, e.g. as the air is cooled during the often long hose transport to the water-damaged area and the energy in used high-pressure fans is not used correctly. 4) With current technology, temperatures and air volumes are not measured, which means that it is not possible to check that the installation is done in an optimal way.

Object of the invention Based on the above, it is an object of the invention to avoid the stated disadvantages of known methods resp. air drying plants provide a new and simple method and plant of the specified type, in which used components are easy to handle, costs and sound levels are lower, available energy is used efficiently and simple control and monitoring is allowed.

Brief description of the invention This and other objects are achieved in a method according to the invention which is of the kind initially stated and which has the characteristics stated in the characterizing part of claim 1.

The invention has the important advantage that only one product is required, which can be set up in one, e.g. by flood damaged by moisture, local and in which all treatment of the air takes place.

This means that installation and handling are significantly facilitated and that the space requirement for the drying operation is very small.

When the method is applied, the price will be significantly lower compared to established technology where a large number of components are required.

An additional advantage is that a very low noise level is obtained, as all components are collected in a heat- and sound-insulated box. This means no inconvenience to those who live or work in the vicinity of the moisture-damaged space. In practice, the sound level can be as low as 46-47 dB, which corresponds to very high requirements.

By treating the air in a heat-insulated box and that the air also constitutes cooling air for the high-pressure fan's electric motor, all available energy to the pressurized dry air is recovered and preserved before it is directly supplied to the water-damaged structure.

This means that the construction receives significant heating, e.g. to 60 to 80 ° C, whereby the water vapor pressure increases as well as the water evaporation and a correspondingly significantly shorter drying time is obtained.

Using the method according to the invention, a drying time which is only 1 / 5-1 / 10 of what can be obtained with established technology can be achieved.

According to DE, A1, 38 15 161 (Getro-Gebäudetrocknung) a device for drying insulated layers in a building is known, in which two high-pressure fans with mutually operatively connected shafts are used which are driven by one and the same electric motor in an insulated box. Air is sucked directly from the floor construction into the box by means of one high-pressure fan, pressurized and supplied to a drying device located outside the box, in which the air is dried and returned via a hose to the other high-pressure fan inlet for renewed pressurization and supply to the water-damaged area. The publication suggests the possibility of also arranging the drying device inside the insulated box, which would thus involve the use of two houses or boxes, one inside the other. This would increase the complexity, size, weight and price of the plant and also jeopardize its function, e.g. since it is unclear where in the house the drying device should in that case be placed and how it should in an optimal way be brought to cooperate with the two high-pressure fans driven by the same electric motor. According to the present invention, a low pressure fan fed, by a drying rotor in a first process air chamber heated and dried process air is sucked into a second chamber in the housing delimited by said first process air chamber by means of a drying rotor, which second chamber receives a high pressure fan, so that the process air passes and is heated by the electric motor before it is supplied to the fan inlet, whereupon the pressurized and temperature-raised dry air is directly supplied to the water-damaged layer or area via the outlet arranged from the other chamber, to which the high-pressure fan outlet is connected.

The advantages of the invention in relation to the latest known techniques described above are mainly conditioned by the fact that all treatment of the air takes place in the two separated chambers having an insulated housing and that the pressurized, heated to 60 to 80 ° C and dry air (0, 5 - 1.5% relative moisture) is forced into the water-damaged layer or area, whereby the temperature of the structure increases sharply and the water vapor pressure in existing pores rises sharply and thus the evaporation. The dry air with a high temperature and thus a great ability to absorb water picks up water which is carried away and leaves the layer or area, whereupon the air is again sucked into the insulated house and dehumidified.

In practice, it is preferred that the process air is supplied to said first process air chamber via a filter which partially limits a space inside the inlet, separated from the process air chamber arranged for collecting any particles present in the incoming air, e.g. sand.

The energy in the wet regeneration air leaving the house can be supplied via a heat exchanger or condenser to the incoming process air, before it is sucked into the first process air chamber via the inlet of the low-pressure fan. In this way an air is obtained which is even warmer and drier.

In practice, it is also preferred that a part of the process air in the second chamber after heating the motor of the high-pressure fan without passing the high-pressure fan exits via a special damper-regulated outlet from the second process air chamber.

According to another aspect, the invention also relates to an air drying plant with a drying rotor, the essential characteristics of which are stated in claim 5.

Advantageous further developments of this air drying plant are stated in the following requirements.

An embodiment of the invention will be described below with reference to the accompanying schematic drawings.

Brief description of the drawing figures Fig. 1 is a partially cut-away perspective view of an air-drying plant provided with a drying rotor according to the invention.

Pig. 2 is a cross-section through a room in a building with a water-damaged floor insulation layer, in which room an air drying plant according to Fig. 1 is set up.

Pig. 3, finally, is a cross section through an air drying plant according to Fig. 1.

Description of preferred embodiments An air drying plant consists of a housing 1 provided with a sound and heat insulation 3, which occupies all the components belonging to the plant. A vertical wall 4 which in a recess receives a drying rotor 5 delimits together with a horizontal floor 6 approximately in the middle of the housing a first process air chamber 7 from a second process air chamber 8. The housing is supported by wheels 13 which cooperate with support 13a and has a transport handle 49.

The air 10 to be treated is included in the first process air chamber 7 via an inlet 2 and passes a process air filter 9 which is located in a sound-insulated filter box 11 just inside the 582 635 filter inlet. In the filter 9 resp. the box 11 is collected in the incoming air any particles, e.g. sand.

The process air is forced via a low-pressure fan 12 into the first process air chamber 7. Due to the overpressure in this chamber 7, the air 21 is forced through the drying rotor 5 which is provided with ducts which contain moisture-absorbing means, e.g. silica gel crystals. The rotor 5 is continuously rotated by means of a motor 14 via a drive belt 15.

The main part of the process air 21 pressurized by the process air fan 12 flows through a first portion of the rotor 5 where it is dehumidified and as dry air 16 enters the second process air chamber 8 (cf. the arrows 16) where it flows down into the lower part of the plant and passes an electric motor. 17 to a high pressure fan 18 during cooling of the engine and further heating of the dry air before it is included in the inlet 18a of the high pressure fan 18 for pressurization.

A second part 22 of the air dehumidified in the rotor 5 is deflected by a cover 23 arranged in the second process air chamber 8 next to the rotor provided with heat-emitting means 24. The hot regeneration air - marked by the arrow 25 - returns through about 1/4 of the rotor 5 where it absorbs the moisture adsorbed in the rotor. It leaves the rotor as wet air 26 and passes out through the plant's wet outlet 29 to be transported to the surroundings via hose (not shown).

Instead of a cover 23 which diverts a partial flow of the dry air from the rotor 5, air can be supplied from outside and pressurized by a fan (not shown) and heated by heat-emitting means to be used as regeneration air.

Prior to this, the energy in the wet regeneration air leaving the housing can be supplied via a heat exchanger or condenser (not shown) before the process air is included in the housing 1 via the inlet 2. 502 655 The regeneration of the rotor 5 becomes more efficient if the heat emitting means 24 23 are placed close to the rotor 5, so that radiant heat is directed directly towards the moisture adsorbent in the rotor.

The dry and hot air leaving the outlet 18b of the high pressure fan 18 has a temperature of 60 to 80 ° C and a relative humidity of 0.5-1.5%. The outlet 18b of the high pressure fan is connected via a hose 27 to the outlet 19 from the housing 1, from where the dry and hot air of high pressure via a hose 28 is led directly into the water-damaged insulating layer 30 under the concrete floor 31 in the relevant room 32. thereby undergoing considerable heating, whereby the water evaporates and is carried away efficiently by the hot and dry air which in the form of wet air seeps out into gaps 33 and is sucked into the inlet 2 of the drying plant in the manner indicated above.

The second process air chamber 8 further has an outlet 36 regulated by a damper control 35 through which dry hot air 16 which has not been pressurized by the high-pressure fan 18 can be taken out for any possible additional drying purposes, e.g. to dry a wall in a room whose floor insulation layer has been damaged by water.

On the front of the housing 1 there are a number of devices for the operation and operation of the drying plant, namely an electrical connection 40, an operating time meter 41, air flow and temperature indicators 42, on-off switches 43, control lamps 44, 45, a hygrostat 46 and overtemperature protection 47.

The rotor 5 in a recess partition wall 4 on which also its electric motor 14 is mounted can be inserted as a cassette and placed in the upper part of the housing 1 and thereby delimits together with the horizontal bottom wall 6 the two process air chambers 7 and 8 of the housing from each other. The main part of the second process air chamber 8 is located in the lower part of the housing where it accommodates the high pressure fan 18. It is understood that the air drying plant as a whole through the said delimitation and arrangement with the high pressure fan in the lower part of the house obtains a very compact design and that the plant as a whole contains a small number of components. The heat energy developed by the high-pressure fan motor is used to the maximum to improve the drying capacity of the discharged air, at the same time as the fan motor receives a satisfactory cooling of the process air before it is included in the fan inlet 18a.

Existing indicators 42 for temperatures and air volumes make it possible to carefully check that the installation of the system has been done in an optimal way.

Other important advantages of a plant according to the invention in relation to the prior art are that it is not a closed system; the dehumidifier's low pressure fan, which is a cheap, light and low energy consuming unit, sucks air freely from the room.

Furthermore, the insulated box 1 does not accommodate a separate, complete dehumidifier, but the entire product is built up as a single integrated unit, ie it does not constitute a combination of different assembled separate units. The dehumidifier's high-pressure fan 18 also pushes dry air directly into the water-damaged layer via the hose 28, ie it is not connected to other components in the system via a number of suction hoses.

All these characteristics of the plant according to the invention make it small, light and easy to handle, for example in connection with movement to different places of use.

Claims (10)

502 655 ll Patent claim A method of increasing the yield of an air drying process in which a drying rotor accommodated in a first process air chamber in a heat and sound insulated housing is supplied, process air fed by a low pressure fan is dehumidified and dried during moisture exchange with heated regeneration air and exits via an outlet from the housing. for example a water-damaged layer or area in a building, characterized in that the process air dehumidified and heated in the dryer rotor is sucked into a second chamber in the housing occupied by a first motor chamber delimited from said first process air chamber, provided with a high-pressure fan provided with an electric motor, so that the process air passes and is heated by the electric motor before it is supplied to the fan inlet, and that the pressurized and temperature-increased process air is supplied directly to the water-damaged layer or area via the outlet in the second chamber of the housing to which the high pressure fan outlet is connected. 2. A method according to claim 1, characterized in that the process air is supplied to said first process air chamber via a filter which partially delimits a space inside the inlet, delimited from the process air chamber arranged for collecting any particles present in the incoming air, e.g. sand. 3. A method according to claim 1 or 2, characterized in that the energy in the wet regeneration air leaving the house via a heat exchanger or condenser is supplied to the incoming process air before it is sucked into the first process air chamber via the inlet of the low pressure fan. 4. A method according to any one of claims 1-3, characterized in that part of the process air in the second chamber after heating the motor of the high-pressure fan without passing the high-pressure fan departs via a special damper-regulated outlet from the second process air chamber. 502 635 12 An air drying plant with a drying rotor comprising: a) an insulated housing (1) provided for installation in a moisture-damaged room or space, provided with an inlet (2) and an outlet (19), b) a recess in a wall (4); ) in the housing (1) accommodated drying rotor (5) with channels containing moisture adsorbents, e.g. silica gel crystals, which rotor receiving wall (4) forms a boundary between first and second chambers (7, 8) for process air in the housing (1), c) a motor (14) for preferably continuous drive of the rotor (5), d ) a low-pressure fan (12) in the first process air chamber (7) for pressurizing air supplied via the inlet (2) so that it flows through a first portion of the rotor (5), e) means (in the second process air chamber (8) present 23, 24) for heating air to be passed as regeneration air in the opposite direction through a further portion of the rotor (5), f) an outlet (29) for wet regeneration air, characterized in that the second chamber (8) for process air in the housing (1) receives a high-pressure fan (18) provided with an electric motor (17), to which the dehumidified and heated process air emanating from said first portion of the rotor is supplied, so that the air passes and is further heated by the electric motor (17) of the high-pressure fan. before it is included in the inlet of the high-pressure fan p (18a) and after pressurization via the housing outlet (19), to which the outlet (18b) of the high-pressure fan is connected, the water-damaged layer or area (30) is supplied directly. An air drying plant according to claim 5, characterized by a space (11) partially delimited in the housing inside the inlet inside the inlet of a process air filter (9) arranged for collecting any particles present in the incoming air, e.g. sand. Air drying plant according to claim 6, characterized in that energy in the wet regeneration air leaving the housing (1) is supplied via a heat exchanger or condenser 502 655 13 before the process air is included in the housing via the inlet (2). Air drying system according to one of Claims 5 to 7, characterized in that the second chamber (8) has a damper-regulated second outlet (36) for process air heated by the high-pressure fan electric motor (17) which has not been pressurized by the high-pressure fan. Air drying plant according to one of Claims 5 to 8, characterized in that the wall (4) receiving the rotor (5) together with a boundary wall or floor (6) located in the middle of the housing delimits the first process air chamber (7) from the other, and that the high-pressure fan is accommodated in the housing and the lower part of the second chamber, substantially below said horizontal wall or floor (6). Air drying plant according to one of Claims 5 to 9, characterized by a number of operating and indicating means for the plant arranged on the side of the housing which occupy the inlet and outlet (2; 19) of the plant, such as operating time meters (41), air flow meters and and temperature indicators (42), indicator lamps (44, 45), hygrostat (46) and overtemperature protection (47).