Apparatus for bringing air and water into a mutual interaction and arrangement for treating indoor air

The invention relates to an apparatus according to the preamble of claim 1 for bringing air and water into a mutual interaction.

The invention relates also to a liquid sprayer according to the preamble of claim 15, particularly a water sprayer.

The invention relates also to an arrangement according to claim 16 for treating indoor air. The invention further relates to a space ventilation system according to claim 23.

Various devices are known in the prior art, which are intended for treating air by means of water, especially water drops, e.g. for cleaning the air.

Water drops are produced e.g. by means of a sprinkler, such as a jet nozzle. A disadvantage is that sprinkler-produced drops are large in size and, thus, not ca- pable of establishing an adequate interaction between air and water. The amount of water needed in the equipment becomes very large in an effort to compensate for a poor interaction. One effective device for producing small water drops is a water sprayer. The employed water sprayers are generally nozzles with one or more small orifices for spraying purified water therethrough. A disadvantage is e.g. the ineffectiveness of equipment, such as an inadequate interaction between air and water and a high consumption of water, complexity, and a high consumption of energy, particularly due to a high water pressure required by the nozzles. Besides, the nozzles become easily blocked.

It is an object of the invention to eliminate the disadvantages associated with known devices in the prior. Another object of the invention is provide a new improved apparatus for bringing air and water into a mutual interaction, said apparatus being capable, depending on a given application, of making an impact on the properties of either air or water, such as temperature, air humidity (water content), oxygen content of water, purity of air/water, for achieving a desired condition. Various regulating arrangements for the climate of an open or closed space, such as the climate of a greenhouse are known in the prior art, which arrangements are intended for controlling temperature and humidity of the space. Regulating sys-

terns known in the prior art, wherein water jets are produced by means of sprinklers or water mist is produced through nozzles at a high pressure in a greenhouse or in an adjoining treatment space, some of said water jets/water mist evaporating and at the same cooling indoor air of the greenhouse or the indoor air of the greenhouse circulated through the treatment space. A disadvantage is, among other things, the fact that the use of water jets is ineffective in terms of the interaction of air and water, as already pointed out above in reference to sprinklers, the amounts of water needed in the system becoming large as the regulated space is large in volume. A disadvantage in the systems involving the use of noz- zles is the quality of water. The water used for producing water mist has to be pure, nor may it contain any extra particles or the like. Otherwise, the nozzles become very easily blocked. A disadvantage is a high consumption of energy as the nozzles require a high pressure for producing water mist. Another disadvantage is also a high consumption of water. In an arrangement according to the invention, the objective is to improve and optimize the climate or indoor air of a closed space, especially a greenhouse, such as to sustain greenhouse conditions optimal from the standpoint of growth.

An apparatus according to the invention for bringing air and water into a mutual interaction is characterized by what is presented in claim 1. Preferred embodiments for an air and/water treating apparatus are presented in the dependent claims.

An advantage offered by the apparatus according to the invention is its ability to achieve an effective interaction between air and water, and specifically with a low consumption of energy as compared to prior known equipment.

An advantage gained by the apparatus according to the invention is that the amount of water fed into the water sprayer can be adjusted according to a given application and that the amount of water fed into the water sprayer is small with respect to the amount of air passing through the apparatus. Another advantage is that the water sprayer most preferred from the inventive standpoint is effective in terms of producing water mist and ineffective in terms of consuming energy. An advantage offered by the apparatus according to the invention is its simplicity and modularity. The apparatus is structurally unitary and compact. The use of several apparatus units enables constructing and assembling systems of varying performances for the treatment of either air as well as water, or even both.

An advantage obtained by the apparatus according to the invention is its capability of being adapted to operate as a separate independent treatment unit. Thus, in the most preferred case, the apparatus is not connected at all from air inlet or outlet channels by pack discharges to any air conditioning system but, instead, these channels open directly to a space to be treated and regulated for its indoor air. Another advantage of the invention is that several apparatus units, functioning as independent treatment units, can be accommodated in an indoor space, such as e.g. in an arrangement according to the invention, and all these units are adjusted for an identical impact on the properties of indoor air. A liquid sprayer, especially a water sprayer, according to the invention is characterized by what is presented in claim 16.

An advantage offered by a liquid sprayer of the invention is the ability to disperse liquid, particularly water, into extremely tiny droplets, the mist, and this is moreover achieved in an energy-saving manner. A particular advantage gained by a liquid sprayer of the invention is that the liquid is not set in a centrifugal motion but, instead, an impeller has its blade members striking against a liquid flow being supplied across an intermediate space between the blade members. It should be noted that the amount of water fed into the liquid sprayer per unit time is proportioned to the performance of an employed power unit and to the dimensions of an impeller.

An advantage offered by an impeller and a liquid discharge element included in a liquid sprayer of the invention is that the latter is not highly susceptible to blocking, even if the liquid, such as water, should carry along impurities and small fragments of debris into the liquid sprayer. Impurities and debris simply migrate through the liquid discharge element and weave through between the impeller's blade members. Another advantage is that such a liquid supply system does not require a high performance and fluid pressure of a pump or the like used for conveying the liquid to the supply system's pipe section.

An arrangement according to the invention for treating indoor air is characterized by what is presented in claim 16.

The arrangement according to the invention for treating indoor air comprises at least one apparatus consistent with the invention and presented in claims 1-14 for bringing air and water into a mutual interaction, wherein a fan is used for delivering indoor air by way of an inlet aperture into a treatment chamber of the apparatus

and for bringing it into an interaction with water mist produced by a water sprayer and for discharging it from the treatment chamber by way of an outlet channel and an outlet aperture back into the indoor space.

An advantage gained by an arrangement of the invention is that a treatment of the indoor air for a space, especially for a large continuous space, such as a greenhouse, can be performed effectively by accommodating therein at least one, but most preferably a number of apparatus units according to the invention, specifically capable of having an impact on indoor air, particularly on its temperature and/or humidity. What is beneficial is that the space does not require the installa- tion of any air duct systems. This represents a substantial reduction in the arrangement installation costs.

An advantage provided by an arrangement of the invention is that the temperature and moisture conditions of indoor air in a space, such as a greenhouse, can be maintained in a substantially consistent manner at desired and predetermined guideline values. The arrangement according to the invention, which comprises a number of apparatus units of the invention, enables also circulating the indoor air in various parts of a closed space without separate fans or other auxiliary systems.

A space ventilation system according to the invention is characterized by what is presented in claim 23. The space ventilation system according to the invention comprises at least two apparatus units according to the invention and presented in claims 1-14 for bringing air and water into a mutual interaction, wherein a first apparatus is adapted to treat indoor air and to discharge it to the exterior of the space and a second apparatus is adapted to treat outdoor air and to convey it into the interior of the space, and wherein the water supply and discharge systems of the first and second apparatus units are interconnected in such a way that water circulates therebetween either directly or by way of an appropriate water storage.

The invention and further benefits thereof will now be described in more detail with reference to the accompanying drawing, in which fig. 1 shows one apparatus of the invention from above in a partly sectional view A-A; fig. 2 shows the apparatus of fig. 1 from the front in a partial vertical section B-B;

fig. 3 shows the apparatus of figs. 1 and 2 from the side in a second partial vertical section C-C; fig. 4 shows a second apparatus of the invention from above in a partly sectional view; fig. 5 shows a third apparatus of the invention from above in a partly sectional view; fig. 6 shows a fourth apparatus of the invention from above in a partly sectional view; fig. 7 shows a fifth apparatus of the invention from the front in a partly sec- tional view K-K; fig. 8 shows the fifth apparatus of the invention from above in a partly sectional view M-M; fig. 9 shows one preferred water sprayer from the side in a partly sectional view; fig. 10 shows the water sprayer of fig. 6 in an enlarged sectional view F-F; fig. 11 shows a detail of the water sprayer, especially a cross-section for part of an impeller and particularly blade members; fig. 12 shows a water discharge element in a side view; fig. 13 shows one arrangement of the invention for treating indoor air; fig. 14 shows a second arrangement of the invention for treating indoor air; and fig. 15 shows a ventilation system implemented by means of an apparatus according to the invention.

Like elements in the figures are designated by like reference numerals.

Some advantageous apparatuses according to the invention have been illustrated in the figures.

An apparatus 1 for bringing air and water into a mutual interaction comprises: a jacket 2, a treatment chamber 3, air inlet and outlet channels 31 , 32, a water sprayer 4, a water supply system 5, and a fan 6. The jacket 2 constitutes an en-

closure or housing. The jacket 2 assembles and holds essential elements of the apparatus 1 together.

The treatment chamber 3 is arranged inside the jacket 2. The treatment chamber 3 is structurally an airtight closed space. It has no significant air leaks. The air inlet and outlet channels 31 , 32 are in communication with the treatment chamber 3. These channels 31 , 32 open outside the jacket 2 by way of an inlet aperture 310 and an outlet aperture 320, respectively, and air is delivered thereby in and out of the treatment chamber 3. The water sprayer 4 is arranged in the treatment chamber 3. The water supply system 5 is connected to the water sprayer 4 for feeding the water.

The fan 6 is connected to the treatment chamber 3, especially to the air inlet channel 31 in association therewith. The fan 6 is fitted in connection with the air inlet channel 31 preferably completely (see figs. 1-3) or at least partially inside the jacket 2. Alternatively, the fan 6 is fitted just outside the jacket, but in a direct con- tact with the inlet channel 31 and its inlet aperture 310 (shown in dashed lines in figs. 1 and 3). The fan 6 has its inlet aperture (and hence the air inlet aperture 310) preferably provided with a protective screen 9 or the like. The migration of debris, insects or the like into the fan 6 and the apparatus 1 by way of the air inlet channel 310 is prevented by means of the protective screen 9. The fan 6 is preferably an axial fan. The fan 6 has a performance which, e.g. in the embodiment of figs. 1-3, is within the range of 1-5 kW, but it may differ even significantly from this rating, depending on a given application and dimensions of the apparatus 1. The fan 6 is capable of producing amounts of air which fluctuate e.g. within the range of 0,5-5 m ³ /second. The fan 6, the power unit of which is an elec- trie motor, such as a short circuit motor, is most preferably adjustable for its rotational speed and amount of air/unit time e.g. by means of a frequency converter.

In the apparatus 1 , the water delivered by way of the water supply system 5 is atomized by means of the water sprayer 4 into microscopically tiny water droplets in the treatment chamber 3. Consequently, the water droplets and the air delivered through the treatment chamber 3 by means of the fan 6 end up in an intensive interaction with each other.

The apparatus 1 according to the invention is generally used for treating air and water. The primary target of treatment is either water or air, or possibly even both, the principal intended service of the apparatus thus varying according to a given

application. Hence, the apparatus according to the invention is applied e.g. to a treatment of air, such as purification (removal of gaseous impurities and/or particles), humidification/dehumidification (i.e. changing the humidity level of air), cooling and/or heating, or to a treatment of water, such as aeration (oxidation), purifi- cation, cooling and/or heating. The apparatus 1 according to the invention is capable of being applied to the separation of pure water (outgoing airflow) from the brine solution used as feed water (or generally from dirty water) and to the separation of water-soluble gases from the air into the feed water.

The apparatus 1 is designed as an integral unit, a module, which in a preassem- bled condition is ready for shipping and mounting on a desired location and with an appropriate control system adaptable and tunable to operate in a desired application for the treatment of air, water or both. The apparatus 1 is a separate and independent treatment unit.

In its space geometric shape the jacket 2 of the apparatus 1 is preferably a cylin- der. In this case, the jacket's 2 bottom segment and top segment are flat surfaces, the peripheral line of which is preferably regular, e.g. a circle, an ellipse, a polygon or a combination thereof. The jacket's 2 side segment(s), interconnecting the top and bottom segments with each other, follows said peripheral line and has a width (i.e. at the jacket's height) which is of constant extent. In the most preferred em- bodiments of the invention shown in the drawings, the jacket 2 is in the shape of a rectangular prism. Thus, the jacket 2 comprises side segments 21 , a bottom segment 22 and a top segment 23, which are all at right angles to each other and all rectangular in shape.

In one preferred embodiment of the invention, the apparatus has its jacket 2 pro- vided with an insulating layer 24, having a thickness of e.g. 10-80 mm. The insulating layer is composed of e.g. polyurethane foam. The insulating layer has a function of providing thermal insulation and preferably also sound insulation for the apparatus 1. An advantage provided by the insulating layer is the capability of maintaining the apparatus' 1 surface at ambient temperature irrespective of the tem- perature of feed water. Thus, no bleeding occurs at the external surface of the jacket 2, e.g. when the temperature of feed water is lower than that of ambient air. Another benefit is the insulating layer's ability to suppress the noise produced by the apparatus 1 , especially by the fan 6.

The air inlet and outlet apertures 310, 320 are provided in connection with the jacket 2. In the apparatus embodiments shown in figs. 1-8, the air inlet aperture

310 is included in one side segment 21 of the jacket 2 and the outlet aperture 320 in its top segment 23. As an alternative, both apertures can be included in side segments (or generally in a side segment), yet on opposite sides of the apparatus and the jacket. The treatment chamber 3 is adapted to have a shape which substantially matches the space geometric shape of the jacket 2. It should be noted, however, that the inlet and outlet channels 31 , 32 do occupy some of the jacket's volume. In a preferred embodiment, e.g. in the embodiment shown inn figs. 1-3, the treatment chamber 3 is an elongated space, its length p exceeding its maximum width I, and height k. The treatment chamber 3 has its length p and height k approximately matching the corresponding dimensions of the jacket 2. In the illustrated embodiment, the treatment chamber 3 has its maximum width I falling short of a width Iv of the jacket, since the fan 6 is fitted inside the jacket 2 and some of the jacket's 2 volume is occupied thereby. Hence, the elongated treatment chamber 3 comprises an intermediate segment 3a and end segments 3b, 3c, which in this case position themselves at the ends of the jacket 2.

In one preferred apparatus according to the invention, the jacket 2 has dimensions as follows: the length p = 2400 mm, the height k = 1200 mm, and the width Iv = 1200 mm. It is obvious that said dimensions of the apparatus are subject even to major deviations. Thus, the apparatus may have its width Iv varying e.g. within the range of 1000-2400 mm, its height k within the range of 1000-2000 mm, and its length p within the range of 1500-3000 mm. Other jacket dimensions are also possible.

In a preferred embodiment of the apparatus according to the invention, the elon- gated treatment chamber 3 presents a shape modified from a rectangular prism to make it symmetrical with respect to a middle plane C-C transverse to the longitudinal direction. The treatment chamber 3 has its top and bottom surface most preferably coinciding with the jacket's 2 bottom and top segment 22, 23.

The inlet and outlet channels 31 , 32 are accommodated inside the jacket 2. The inlet channel 31 is adapted to extend from the inlet aperture 310 to the treatment chamber 3. The inlet channel 31 is preferably a straight channel. The inlet channel 31 is e.g. a circle or a rectangle (square) in cross-section. The inlet channel 31 is a short channel, extending through the jacket 2 to the treatment chamber 3.

The treatment chamber 3 is contiguous, preferably over a peripheral region of the treatment chamber, to the air outlet channel 32 and further to the outlet aperture 320. The outlet channel 32 is designed in either of two optional configurations, one of said options further involving two possible configurations. In the first option, the outlet channel 32; 32a, 32b, the number of which is one (see fig. 5) or, in a preferred embodiment, two (see figs. 1-4, 6), comprises a straight outlet channel section 321 ; 321a, 321b, which is additionally in the shape of a circular cylinder. The treatment chamber 3 is adapted to communicate by way of a connecting port 30; 30a, 30b directly with the outlet channel section 321a, 321 b. In a preferred embodiment of the apparatus according to the invention, the air inlet channel 31 and the straight outlet channel section 321 ; 321a, 321b are angled, preferably at a 90-degree angle, relative to each other. The number of straight outlet channel sections 321 ; 321a, 321b is one (see fig. 5) or preferably two (see figs. 1-4, 6) and these are contiguous to the treatment chamber 3 in a peripheral region thereof at a distance from the inlet channel 31 , particularly from the point at which the latter joins the treatment chamber.

In the second option, the outlet channel 32; 32a, 32b comprises a curved outlet channel section 322; 322a, 322b and a straight outlet channel section 321 ; 321a, 321b, the number of each being one or preferably two, just like the number of out- let channels. The curved outlet channel section 322; 322a, 322b refers to a channel section which has its principal direction (and the direction of flowing air) adapted to deflect and change (and especially over to the same side, such as to the right or to the left as considered - see arrows - in the direction of flow), when proceeding along the channel section from its inlet end to its outlet end. The treatment chamber 3 is adapted to engage with the curved outlet channel section 322. The curved outlet channel section 322 is in turn linked with the straight outlet channel section 321 by way of the connecting port 30.

In addition, the second option involves two configurations. In the first configuration, the curved outlet channel section 322; 322a, 322b is set substantially flush with the treatment chamber 3 (see figs. 1-3), i.e. as a straight extension of the treatment chamber. In the second configuration, the curved outlet channel section 322; 322c is set in an upper portion of the jacket 2; 2a above the actual treatment chamber 3 (see figs. 7 and 8). The first configuration is more beneficial than the second, because it results in a lesser height for the apparatus 1 ; 1a and for the jacket 2; 2a. Besides, the first configuration is structurally simpler than the second.

Also, in the first configuration, the apparatus is functionally more efficient as the resistance to an airflow passing through the apparatus is lesser than in the second design.

In either option, the airflow proceeding in the outlet channel 32; 32a, 32b is influ- enced by centrifugal forces, forcing the particles present in the airflow, especially small water drops, against the inner walls of the outlet channel, such particles clinging thereto and trickling downwards. This way, the outgoing airflow can be effectively cleared of most of the water drops, the body of water established thereby being most preferably collected for storage. The removal of water drops from the airflow emerging from the apparatus is important because, depending on a given application of the apparatus, the water contains, among other things, thermal energy or adverse components, the ending-up of which is not desired in an airflow going out of the apparatus.

In preferred embodiments of the apparatus according to the invention, which are consistent with the above-described first option, the air outlet channel 32; 32a, 32b comprises two straight outlet channel sections 321 ; 321a, 321b (see figs. 1-4 and 6). The outlet channel sections 321 ; 321a, 321b are provided in the treatment chamber's 3 opposite peripheral regions, such as in the treatment chamber's 3 end segments 3b, 3c. The outlet apertures 320; 320a, 320b are included most pre- ferably in the jacket's 2 top segment 23. Thus, the air inlet channel 31 is united at its outlet end with the treatment chamber's 3 middle segment 3a, such that the inlet aperture 310 is in the jacket's 2 side segment 21.

The treatment chamber 3 is connected at each end segment 3b, 3c to the air outlet channel 32; 32a, 32b, particularly to the outlet channel section 321 ; 321a, 321b, by way of an appropriate connecting port 30; 30a, 30b. In the above-described exemplary embodiment, the connecting port 30; 30a, 30b is located at the outlet channel section's 321 ; 321a, 321 b upstream end and is substantially parallel to the outlet channel section's 321 longitudinal axis. At the same time, the connecting port 30 is substantially perpendicular to the jacket's 2 bottom and top segment 22, 23. The connecting port 30 is elongated, substantially rectangular in shape and has a length (height) yk which is a portion, preferably 20-80%, most preferably about 35-50%, of the outlet channel's 32 total length k. The connecting port 30 has a width which covers most preferably the range of 30-90 degrees, such as 45 degrees, of the circumference of a circle and hence of the outlet channel section 321. The connecting port 30 has a surface area which is preferably half or even less

than that as compared to the surface area of the air inlet aperture 310. Thus, the connecting port 30 develops a throttling airflow with a high rate of speed.

In preferred embodiment of the invention, the treatment chamber 3 is adapted to converge from the middle segment 3a towards the end segment 3b, 3c (see figs. 1-6). At the same time, the treatment chamber 3 and the flowing direction of air (see arrows) is adapted to deflect, i.e. to change its direction, from an imaginary longitudinal plane B1-B1 of the treatment chamber by 45-360 degrees, in the embodiments of figs. 1-5 preferably by more or less 90 degrees, upon reaching the connecting port 30; 30a, 30b. The treatment chamber's longitudinal plane B1-B1 is perpendicular to the middle plane C-C.

In a preferred embodiment of the invention (the first configuration), fig. 6, the treatment chamber 3, particularly its end segment 3b, 3c, is provided with a straight extension (in the flowing direction of air) in the form of a curved outlet channel section 322; 322a, 322b, which is also flush with the treatment chamber 3. A deflection of the air flowing direction over the range of 90-360 degrees (or even more) between the treatment chamber 3 and the straight outlet channel section 321 ; 321a, 321 b is feasible by means of the curved outlet channel section 322; 322a, 322b. The curved outlet channel section 322; 322a, 322b is adapted to wrap around the straight outlet channel section 321 ; 321a, 321 b and to join the latter by way of the connecting port 30; 30a, 30b.

In the above-described embodiments, the treatment chamber 3 is communicated with the connecting port 30; 30a, 30b in such a way that the airflow can be delivered from the treatment chamber 3 (either directly or by means of the curved outlet channel section 322) straight into the outlet channel section 321 ; 321a, 321 b at least in a roughly tangential fashion. Thus, the airflow in the outlet channel section 321 ; 321a, 321b develops a spinning spiral motion adapting to its inner surface and proceeding towards the outlet aperture 320; 320a, 320b. As a result of this, the centrifugal forces apply an impact on extremely diminutive water droplets present in the airflow, which hence ultimately collide with the inner surface of the out- let channel 32, especially the curved and/or straight outlet channel section 321 , 322. The result is that the airflow discharging from the apparatus can be effectively cleared of liquid-state water (and collected for storage at the same time).

In another embodiment of the invention, figs. 7 and 8 (the second configuration), the curved outlet channel section 322 is set at a different level with respect to the treatment chamber 3; 3 ¹ . In this case, the curved outlet channel section 322; 322c

is present in an upper part of the jacket 2a above the actual treatment chamber 3; 3 ¹ . The treatment chamber 3; 3 ¹ has its peripheral region provided with an aperture 323, which opens from the treatment chamber 3; 3 ¹ to an upstream end of the curved outlet channel section 322; 322c. In this case, the aperture 323 is provided at an upper part of the treatment chamber 3; 3 ¹ in a peripheral region of the treatment chamber 3; 3 ¹ opposite to the inlet channel 31 and the fan 6. The curved outlet channel section 322; 322c traces at least partially a circular arc and extends around the straight outlet channel section 321 ; 321c to the extent of almost 360 degrees and opens at the downstream end by way of the connecting port 30; 30c directly into the straight outlet channel section 321 ; 321c. In this case, the straight outlet channel section 321 ; 321c is relatively short and its cross-sectional shape (a circle, a polygon or some other equivalent geometric form or a combination thereof) does not have any major significance from the standpoint of an outgoing airflow. What is essential is that the outgoing airflow be substantially pointed in one desired direction from the apparatus and its jacket, i.e. in this case upwards from the straight outlet channel section 321 ; 321c.

In the above embodiment, the airflow in the outlet channel 32, especially in the curved outlet channel section 322; 322c but preferably also in the straight outlet channel section 321 ; 321c, develops a motion adapting itself to its outer surface and proceeding towards the outlet aperture 320. Centrifugal forces apply an impact on small water droplets present in the airflow and ultimately those collide with the inner surface of the outlet channel 32, particularly the curved and/or straight outlet channel section 321c, 322c. This enables an effective removal of liquid-state water from the airflow discharging out of the apparatus. In a preferred embodiment of the invention, the apparatus has its jacket 2 in the shape of a rectangular prism, the treatment chamber 3 provided thereinside being appropriately modified from a prism of the basic design. Thus, it is preferred that the internal surfaces of the treatment chamber 3 be surfaces, which are vertical, i.e. parallel to the jacket's 2 side segments 21 , and which are bounded by the jacket's bottom segment 22 and top segment 23 and at the same time against the treatment chamber's bottom and top surface and which are substantially perpendicular to the latter. The convergence and deflection of the treatment chamber 3 from the treatment chamber's middle segment 3a towards its end segments 3b, 3c are implemented by means of first and second guide surfaces 33; 33a, 33b; 34; 34a, 34b. These guide surfaces are provided on opposite sides of the treatment chamber 3 (in its longitudinal direction B1-B1) and symmetrically on various sides

of the middle plane C-C. Both guide surfaces 33, 34 are most preferably curved (or polygonal or complex curved and polygonal) surfaces. It is preferred that the second guide surface 34; 34a, 34b be adapted to meet with the straight outlet channel section's 32; 32a, 32b surface most preferably in the direction of a tangent of the outlet channel's cross-sectional circle

It is preferred that, whenever necessary, guide surfaces 35; 35a, 35b, 35c; 36; 36a, 36b, 36c, 36d, 36e similar to said first and second guide surfaces 33, 34 can be constructed also elsewhere in the treatment chamber 3; 3 ¹ and in the outlet channel 32, such as in the curved outlet channel section 322; 322c (see figs. 5-8). A function of the guide surfaces is to direct and control airflows in the treatment chamber 3 and in the outlet channel 32 so as to provide a passage of air through the apparatus without any major flow resistances and, thereby, with a minimum consumption of energy as regards the fan 6. At the same time, it is the objective that the airflow produced by the fan 6 and the water mist produced by the water sprayer 4 become effectively blended with each other in a sufficiently spacious treatment chamber 3 and over a sufficiently long working time for enabling the interaction to reach a desired effective end result with respect to air or water or both. It should be noted that the guide surfaces can be separate contoured panels or contoured surfaces of the jacket 2; 2a/treatment chamber 3; 3 ¹ . In one alternative embodiment of the apparatus according to the invention, the outlet channel 32 comprises one straight outlet channel section 321 ; 321a, as clearly visualized in the example of fig. 5. The outlet channel section 321 ; 321a is provided in a peripheral region of the treatment chamber 3, such as in one end segment 3b of the elongated treatment chamber 3. The outlet aperture is most pref- erably included in the jacket's 2 top segment. The air inlet channel 31 , and the fan 6 accommodated therein, is provided in a peripheral region of the treatment chamber 3, in this case in the treatment chamber's 3 other end segment 3a. The air inlet aperture 310 is included in the jacket's 2 side segment 21. The treatment chamber 3 has its middle segment 3a fitted with a water sprayer 4. In other respects, the embodiment of fig. 5 is consistent with an apparatus of the invention described above in reference to figs. 1-3.

In this embodiment as well, the treatment chamber 3 is adapted to converge and deflect from the treatment chamber's middle segment 3a towards its end segment 3b, but only towards the first end segment 3b which features a connecting port 30, similar to that in the above-described (figs. 1-3) embodiments, leading to the straight outlet channel section 321 ; 321a. Accordingly, the airflow circulating spi-

rally along the straight outlet channel section's 321 ; 321a internal wall can be implemented just as in the above-described apparatus embodiments, the centrifugal forces applying an impact on small water drops which are flung against the outlet channel section's 321 ; 321a internal wall. In a preferred embodiment of the apparatus according to the invention, the water sprayer 4 comprises a power unit 41 , most preferably an electric motor, and an impeller 42 driven by means of the power unit. In addition, the water supply system 5 comprises a feed pipe 50, having its end, i.e. a discharge element 51 , provided with one or more outlet apertures 52. The discharge element 51 and one or more outlet apertures 52 are provided in a middle segment of the impeller 42, specifically on a center axis or in the vicinity thereof, such that the water supplied from the feed pipe 50 through the discharge element 51 is brought into contact with the impeller 42 for atomizing the water into water mist, i.e. into microscopically tiny droplets. The water sprayer 4, especially its impeller 42, is provided in the treatment chamber's 3 middle segment 3a. In this case, preferably in the elongated and symmetrical treatment chamber's 3 middle plane C-C. In addition, the water sprayer 4 lies in the treatment chamber 3, in its middle segment 3a, in a position which, relative to the middle plane C-C, is essentially the same as that of the air inlet channel 31 and in the illustrated exemplary embodiment also essentially on the same axis.

The water sprayer 4 has its power unit 41 mounted externally of the treatment chamber 3 and at the same time preferably also externally of the jacket 2, such as outside its side segment 1. The water sprayer 4 has its rotating shaft 43, on which the impeller 42 is mounted, adapted to extend through a wall of the jacket 2 (pref- erably through the side segment 21 or optionally the top segment 23) into the treatment chamber 3; 3a. The water sprayer's power unit 41 can be alternatively accommodated in a recess provided in the jacket 2 and reserved therefor.

It is preferred that the water sprayer's 4 impeller 42 be arranged in vertical orientation and at the same time, in this case, co-directionally with a back wall of the treatment chamber 3 (and a back wall 21a of the jacket 2) and at the same time perpendicularly to the air inlet channel 31 , as clearly visualized in the embodiments of figs. 1-3, 5 and 6. In this case, the air inlet channel 31 and the water sprayer's 4 impeller are in register with each other. The water sprayer 4, especially its impeller 42, is alternatively in an offset position relative to the fan 6 and the inlet channel 31 on the vertical plane C-C, such as e.g. high in the treatment

chamber's middle segment 3a, while the inlet channel 31 has its aperture into the treatment chamber in a low position. On the other hand, the relative positions of the air inlet channel 31 and the water sprayer, particularly the impeller 42, can be established in reverse order. Alternatively, the water sprayer 4 has its impeller 42 arranged in horizontal orientation. Thus, the impeller 42 is co-directional with the treatment chamber's 3; 3 ¹ top segment (and the jacket's 2 cover segment) in the treatment chamber's 3 middle segment 3a, as clearly visualized in the exemplary embodiments of figs. 4, 7 and 8. The treatment chamber's 3; 3 ¹ width Iv in these embodiments is more extensive than in the embodiments shown in figs. 1-3, 5 and 6. It should be pointed out that angles of the impeller plane with respect to the treatment chamber's 3 internal walls and at the same time the jacket's 2 walls (and particularly to the cover segment 23) and the inlet channel 31 , other than the angles described above, are feasible, depending e.g. on a given application and a jacket design. Next, a detailed reference is made to a liquid sprayer, specifically a water sprayer 4, which is particularly suitable for use with the apparatus 1 of the invention for bringing air and water into a mutual interaction. In this context, a particular reference is made to figs. 9-12. Reference is also made to the same Applicant's earlier Finnish patent application Fl 20080067. In a preferred embodiment of the water sprayer 4, the impeller 42 comprises a core member 421 which is circular in cross-section and thus cylindrical in terms of its outer periphery. The impeller 42 further comprises an array of blade members 422, mounted on a peripheral region 421a of the core member 421 with equal intervals, with appropriate equal angular gaps, at an equal distance from a center axis D-D, and in a parallel relationship with the rotating shaft 43 and consequently with the center axis D-D. There are preferably a large number of the blade members 422, such as 20-50 specimens, depending on the impeller's 42 diameter h.

The water supply system 5, especially its discharge element 51 , is accommodated in a space, a central space 44, left in the middle of the blade members 422. Most preferably, the discharge element 51 is mounted on the center axis D-D. It is through the water supply system 5 that water is to be delivered against the impeller's blade members 422 in such a way that, in the process of rotating the impeller 42 by means of the power unit 41 , the liquid atomizes, as a result of being struck by the blade members 422, into very tiny droplets (preferably in the order of not more than 10 ^"3 mm in diameter) and at the same time diffuses into ambient air, in

this case particularly into an airflow passing through the treatment chamber 3. The amount of water to be delivered through the water supply system 5 is most preferably adjustable.

In the most preferred embodiment of the water sprayer 4, the impeller 42 is con- figured so as to operate as a fan as well. Thus, the resulting water mist diffuses within an airflow traveling at the same time in a turbulent manner through the water sprayer (see arrows E1 , E2). In this case, in addition to a preferred fan action of the impeller 42, there is a powerful airflow provided through the treatment chamber 3 by means of a separate fan 6, the turbulent blending of air and water mist being enhanced as a result. Because the water drops are microscopically tiny and present in an immense number (N), the water drops and air have a relative surface area (= N x 4πr ² , wherein r = the radius of a spherical drop) thereof becoming extraordinarily large and at the same time the interaction between air and water drops in a turbulent state is highly effective. The interaction is dependent, among other things, upon air and water temperatures and, thus, the evaporation of airborne water, which absorbs a considerable amount of heat, can be extensive and that results in the cooling of air (or vice versa, the condensation of airborne water releases heat, resulting in the warming-up of air and water).

In a preferred embodiment of the invention, the water supply system 5 comprises a discharge element 51 , which has been constructed from preferably a cylindrical hollow component that is most preferably circular in cross-section. The discharge element 51 is accommodated in the space 44 between the impeller's blade members 422 on the center axis D-D or in its vicinity. On various sides of the discharge element's 51 jacket, most preferably at regular distances, there are apertures 52 for discharging the water. The discharge element 51 is mounted in a fixed position relative to the impeller 42. Water is delivered by way of an appropriate feed pipe 50 to the discharge element 51 , e.g. from a suitable water tank, either gravitation- ally (the water tank is placed at a suitable height with respect to the apparatus 1 , and specifically with respect to the water sprayer 4 and the discharge element 51 ) or by means of a pump.

The apertures or orifices 52 of the water discharge element 51 are elongated in the direction of the center axis D-D and preferably arranged symmetrically at a matching level on various sides of the discharge element (when viewed in the longitudinal direction of the discharge element). In one embodiment, moreover, the discharge element 51 includes apertures 52 at several levels in the direction of the center axis D-D (as visualized in fig. 9).

The apertures 52 of the water discharge element 51 are circular holes or alternatively elongated slots oriented in the direction of the center axis D-D. The apertures 51 (31 ) have a diameter b most preferably within the range of 5-10 mm, but may also be larger, even up to 15 mm. Dimensions of the feed pipe 50 and the discharge element 51 and a size of the apertures 52 are dependent on the water sprayer's size and performance, especially on the power unit's 41 performance and the impeller's 42 dimensions. An advantage of this arrangement is that the water supply pressure needed in the water discharge element 51 is slight. The delivery head lift as low as 0,7-1 ,0 m is sufficient for ensuring the water supply pres- sure for the water discharge element 51. A second important advantage is that the employed water does not have to meet high quality requirements: the water sprayer 4 and especially the discharge element's 51 apertures 52 allow the passage of impurities and small debris and, thus, natural waters, such as lake or sea water, can be used as such in the water sprayer. These impurities are also readily able to pass through the impeller 42.

The water sprayer has its impeller 42 preferably constructed in such a way that a leading edge 422a of the blade members 422 lies on the side facing towards the core member's 421 outer periphery 421a, most preferably on the outer periphery or in its vicinity, and a trailing edge 422b of the blade members lies on the side facing the center axis D-D. In addition, the blade members 422 are components which are straight and elongated in the direction of the center axis D-D. The blade members 422 have a certain constant length s, as clearly illustrated in fig. 6. The blade members 422 are flat in sectional plane F-F crosswise to the center axis. The blade members 422 have a ratio of its maximum width a to the impeller's di- ameter h within the range of 1 :5-1 :15, preferably in the order of 1 :10. Consequently, the impeller's 42 blade members 422 are comparatively far away from the center axis and the air is able to enter in the direction of the axis D-D into the space 44 therebetween (see arrows E1 ). In addition, the water supply system's discharge element 51 can be accommodated in the space 44 between the blade members, preferably on the center axis D-D or in its immediate vicinity. The water discharge element 51 does not significantly block the admission of air into the space 44 between the blade members. The advantage is that water is able to discharge from the apertures 52 basically co-directionally with an airflow generated by the impeller 42 and to proceed into the intermediate space 44 between the blade members and, hence, the air and water flows support and intensify each other.

The water sprayer has its impeller 42 preferably constructed also in such a way that the blade members 422 are disposed at an angle α relative to the impeller's 42 radius extending through the midpoint of the center axis D-D (and at the same time the rotating shaft 43) and relative to its diameter h (see figs. 9 and 10). As a result, the impeller and its blade members are enabled to operate the way of a fan, and particularly in such a way that air is drawn in the space 44 at the core member of impellers through an open aperture (arrows E1 , fig. 9) from the end of an impeller and expelled across the impeller's blade members (arrows E2).

In the most preferred embodiment of a water sprayer, the impeller's 42 blade members 422 are convex over what is a first surface in the cross-sectional plane, i.e. an outward surface 4221 thereof, as visualized in fig. 11. A second surface or an inward surface 4222 of the blade members 422 is optionally straight or concave. The blade members 422 are conveniently constructed from sheet metal of a uniform thickness by appropriate bending for providing a blade member convex in one surface and concave in the other surface. Such blade members function the same way as the wings of an airplane, resulting in an outward uplift from the concave surface and at the same time an airflow G from the center axis D-D outward alongside the blade members 422.

The impeller 42 is implemented in one preferred embodiment such that the impel- ler's core member 421 is a substantially flat plane at least over a surface 421c to which the blade members 422 are mounted at the first ends thereof. Most preferably, the core member 421 is a disc-shaped component, in the middle of which the power unit's 41 rotating shaft 43 is conveniently mounted (or mountable during the course of installation). In one option, the water sprayer is preferably constructed in such a way that it includes a second peripherally circular and annular end member 423. Hence, this is provided in the middle with an opening 423a, the outline of which is most preferably also circular. By this opening, air has an uninhibited access into the space 44 between the blade members. The end member 423 and the core member 421 are arranged concentrically on the center axis D-D at a distance s (i.e. the length of the blade members) from each other. The blade members 422 are mounted at the opposite ends thereof to the core member 421 and the end member 423. Benefits provided by this structure include simplicity and sturdiness.

The water supply system 5 has its feed pipe 52 adapted to extend through the jacket 2, in this exemplary embodiment through the bottom segment 22, into the

treatment chamber 3; 3a and further to the water sprayer 4, to the impeller 42 thereof. Alternatively, the feed pipe 52 is adapted to extend co-directionally with the rotating shaft 43 and even in the juxtaposition therewith to the water sprayer's impeller 42. The water sprayer's 4 impeller 42 has dimensions, i.e. its diameter h and the length s of its blade members, which lie preferably within the following ranges of fluctuation: h = 150-300 mm and s = 40-120 mm, but other dimensions are also possible. The amount of water needed in the water sprayer 4 is relatively small, e.g. 1-5 liters/second, and can be regulated as necessary (by means of a pump 53 and/or a valve provided in the feed pipe 52). The power unit 41 has its performance preferably in the order of 1-3 kW. The power unit 41 is preferably an electric motor, most preferably a short circuit motor, having its power supply preferably provided with a regulating device, most preferably a frequency converter. The rotating speed of an electric motor and the spraying of water can be adjusted by means of a regulating device, such as a frequency converter.

The apparatus according to the invention is most preferably embodied by applying a water sprayer 4, the construction and features of which have been described above. It should also be pointed out that the water sprayer 4 can be applied in its own right also in contexts other than in an apparatus constituting the particular ob- ject of this application for bringing air and water into a mutual interaction. In this case, water can be replaced by any given liquid and air can be replaced by a gas or a gaseous mixture, which is most preferably treated in a sealed space. Hence, generally speaking, the question is about a liquid sprayer for bringing a gaseous medium (i.e. a gas or a gaseous mixture) and a liquid into a mutual interaction. In a preferred embodiment of the invention, the treatment chamber 3 has its bottom segment provided with a receiver 8 for collecting the excess water left in the treatment chamber 3 in the wake of water mist produced by the water sprayer 4. Some of the water mist comes to contact with the treatment chamber's 3 internal surface and trickles along the internal surfaces gravitationally down towards the treatment chamber's 3 bottom (and the jacket's 2 bottom segment 22) and into the receiver 8 provided therein. The water is drained from the treatment chamber 3 by way of an outlet 81 provided in the receiver 8. The receiver 8 is most preferably designed in the bottom segment 22 so as to have its surface inclined and sloping towards the outlet 81.

In a preferred embodiment of the invention (see fig. 3), the water supply system 5 further comprises a pump 53 and a water storage 54. The water storage 54 is connected to the feed pipe 50, in which the pump 53 is also fitted. The water storage 54 is for example a water tank or a water basin. From the water storage 54, water is pumped by means of the pump 53 through the feed pipe 50 to the discharge element 51 and further by way of the apertures 51 to the water sprayer 4, particularly to the rotating impeller 42. The treatment chamber 3 has its receiver 8 preferably connected from the outlet 81 by way of a drain pipe 82 to the water storage 54. Hence, established this way is a water circulation system for the appara- tus according to the invention.

In one preferred embodiment of the invention, the water contained in the water storage 54 is replaceable (see arrows at the water storage in fig. 3). As necessary, water in the water storage 54 can be replenished and also drained out, respectively. In a second preferred embodiment of the invention, the temperature of wa- ter in the water storage 54 is measured and regulated, e.g. by recycling the water by way of a suitable heat exchanger in a cooling/heating unit. In a third embodiment of the invention, water in the water storage 54 is purified or treated chemically, e.g. for the elimination of ammonia absorbed from air to water.

In one preferred embodiment of the invention, the apparatus comprises an air dif- fuser 7, which is fitted in the treatment chamber 3 between the air inlet channel 31 , especially the air inlet channel's 31 outlet aperture, and the water sprayer 4, especially its impeller 42. The airflow coming from the air inlet channel 31 and the fan 6 is distributed by the air diffuser 7 into the treatment chamber 3 on various sides of the water sprayer 4. In terms of its geometric shape, the air diffuser 7 is conical in at least one plane. In the illustrated embodiment, the air diffuser is a cone in terms of its shape. The air diffuser 7 has its tip element 71 pointing towards the air inlet channel 31.

The invention relates also to an arrangement for treating indoor air. This arrangement, figs. 13 and 14, comprises at least one apparatus 1 ; 1 ¹ , 1 ² , 1 ³ of the inven- tion for bringing air and water into a mutual interaction. The indoor air refers, for example, to the indoor air of a closed space 10 such as a greenhouse 10a, an animal shelter, and a factory hall.

The arrangement according to the invention lends itself particularly well to treating the indoor air of a greenhouse 10a. The arrangement enables controlling the tern-

perature and/or moisture content (relative humidity) of indoor greenhouse air without direct airing and ventilation performed by way of openable hatches.

In a preferred embodiment of the arrangement according to the invention, the apparatus 1 for bringing air and water into a mutual interaction is established as a separate indoor treatment unit. It is preferred that there be a plurality of apparatus units 1 ; 1 ¹ , 1 ² , 1 ³ , as specifically depicted in figs. 13 and 14. Using a number of units 1 ; 1 ¹ , 1 ² , 1 ³ enables covering even a large area and volume in a closed space in such a way that a characteristic, such as temperature, of the indoor air contained therein can be maintained as desired and changed as necessary. The apparatus 1 ; 1 ¹ , 1 ² , 1 ³ is most preferably set at an appropriate height H from a floor level L of the closed space 10, such as from an indoor growing bed in the greenhouse 10a. The appropriate height H is preferably at least half of a maximum height of the space 10, 10a, i.e. generally within the range of 2-6 m. Hence, the apparatus is most preferably located in the upper part of a closed space. It is pre- ferred that the apparatus 1 ; 1 ¹ , 1 ² , 1 ³ be disposed in a closed space, especially in a greenhouse, above its illuminators V or a plane defined by the illuminators.

When there are several apparatus units 1 ; 1 ¹ , 1 ² , 1 ³ , it is preferred that those be set in the space 10, 10a preferably at an equal height H (alternatively, the height may vary depending on the space) and horizontally at a distance e, preferably a constant distance (yet alternatively, the distances may also be unequal), from each other in various parts of the closed space 10, 10a.

The apparatus 1 ; 1 ¹ , 1 ² , 1 ³ is fixed in the greenhouse 10a or in a corresponding space by means of convenient supporting elements, such as e.g. mounting bars and/or beams and/or mounting cables. The apparatus 1 can have its jacket 2 pro- vided with fastening links and lugs, from which the apparatus can be suspended and secured at an appropriate height H to the supporting structures of a greenhouse.

In a preferred embodiment of the arrangement according to the invention, the apparatus 1 ; 1 ¹ , 1 ² , 1 ³ has its air inlet aperture 310 (and, at the same time, the inlet channel 31 as well) adapted to open in a substantially horizontal direction and its air outlet aperture 320 in a substantially vertical direction upwards. The air inlet aperture 310 in the apparatus 1 is located in the jacket's 2 side segment 21 and the outlet aperture (or outlet apertures) 320 in the jacket's cover segment 23. In a preferred alternative of the invention, in the vicinity of the outlet apertures 320, es-

pecially above the same, there are air deflectors 18, by means of which the vertical airflows coming from the outlet apertures 320 are diffused to proceed in a substantially horizontal level. These arrangements provide for the effective mixing of indoor air, whereby the temperature (and humidity) is consistent and equal in vari- ous parts of the indoor space.

The arrangement according to the invention further comprises, in a preferred embodiment thereof, a circulation water installation 11 , which includes water inlet and outlet pipes 12; 12 ¹ , 12 ² , 12 ³ , 12 ⁴ , 13; 13 ¹ , 13 ² , 13 ³ , 13 ⁴ , at least one pump 14 (or each apparatus 1 ; 1 ¹ , 1 ² , 1 ³ with its dedicated pump 14 ¹ , 14 ² , 14 ³ , see fig. 14), and a water storage 15. The inlet pipes 12; 12 ¹ , 12 ² , 12 ³ , 12 ⁴ are adapted to connect the water storage 15 by way of the pump 14 to the water supply system 5; 50 of the apparatus 1 ; 1 ¹ , 1 ² , 1 ³ . The outlet pipes 13; 13 ¹ , 13 ² , 13 ³ , 13 ⁴ (or the corresponding pipes and/or channels) are adapted to connect outlet apertures 81 of the apparatus 1 ; 1 ¹ , 1 ² , 1 ³ directly or indirectly to the water storage 15. Thus, some of the outlet pipes 13; 13 ¹ , 13 ² , 13 ³ correspond to discharge pipes 82 of the apparatus 1 ; 1 ¹ , 1 ² , 1 ³ or generally to pipe elements attached (removably) to the outlet apertures 81 of the apparatus 1 ; 1 ¹ , 1 ² , 1 ³ .

The circulation water installation 11 is used for pumping water from the water storage 15 arranged to space 10; 10a to the water sprayer 4 of one or more apparatus units 1 ; 1 ¹ , 1 ² , 1 ³ . In the apparatus' treatment chamber 3, the water mist and the indoor air delivered by the fan 6 into the treatment chamber are forced to an effective interaction. At least some of the water (residual water from the water mist and possible water condensed from the indoor air) is collected in the receiver 8 provided in the treatment chamber 3 and further by way of the outlet aperture 81 and the outlet pipes 13; 13 ¹ , 13 ² , 13 ³ , 13 ⁴ back into the water storage 15.

It should be noted that, in one preferred embodiment of the arrangement, the amount of air per unit time (m ³ /sec) delivered by the fan 6 through the treatment chamber 3 and/or the amount of water per unit time (liters/sec) delivered by way of the water sprayer 4 into the treatment chamber 3 are regulated and thereby the ra- tio regarding the amount of air/the amount of water is used to make a difference in the temperature and/or water content (relative humidity) of indoor air. Alternatively, the ratio regarding the amount of air/the amount of water is maintained at an appropriate constant value, which is changed as necessary.

The water held in the water storage 15 included in the circulation water installation 11 is preferably replaceable by way of a suitable supply and discharge piping 16. It

is also preferred that, whenever necessary, the water storage 15 can be replenished with water. The water in the water storage 15 is subject to treatment the same way as the water contained in a water storage 54 used in association with a single apparatus 1. An advantage is that, in this arrangement, the treatment of wa- ter in the water storage 15 proceeds in a centralized manner.

The arrangement according to the invention, in a preferred embodiment thereof, comprises equipment 17 for controlling and regulating the temperature of feed water. The equipment 17 comprises e.g. a heat exchanger, a first circuit 17a of which is used for circulating the water of the water storage 15 (presently therein or arriv- ing therein by way of the outlet pipes 13; 13 ¹ , 13 ² , 13 ³ , 13 ⁴ ) and a second circuit 17b of which is used for circulating an appropriate second medium, having a predetermined temperature which serves as a guideline value for the water storage temperature. Proceeding like this, the temperature of the water storage 15 can be maintained at a desired value or changed as required by the necessary heat- ing/cooling of water and at the same time indoor air as well.

In a preferred embodiment of the arrangement according to the invention, the equipment 17 for controlling and regulating the temperature of water comprises any apparatus 1 constituting an object of the invention, as specifically shown in fig. 14. In this case, the equipment 17 comprises two side-by-side fitted units 1 ; 17 ¹ , 17 ² ', which hereinafter shall be referred to as temperature regulating devices. These devices 1 ; 17; 17 ¹ , 17 ² are most preferably mounted outside a closed space 10, such as a greenhouse 10a, whereby outdoor air is circulated through the treatment chamber 3 thereof from the inlet aperture 310 to the outlet aperture 320, which outdoor air, at least for most of the year, is comparatively cool, even cold and dry (low in relative humidity) on latitudes north, such as in Finland. The water supply system 5, especially the feed pipe 51 , of each temperature regulating device 1 ; 17; 17 ¹ , 17 ² is connected to the outlet pipes 13; 13 ¹ , 13 ² , 13 ³ of the actual treatment units 1 ; 1\ 1 ² , 1 ³ and the circulation water installation 11 by means of a first connecting pipe 13 ⁴¹ and, respectively, the water outlet aperture 81 is linked with the water storage 15 by way of a second connecting pipe 13 ⁴² (and possibly by way of a pump). In the foregoing, the number of temperature regulating devices 1 ; 17; 17 ¹ , 17 ² is two, but depending on a given application, such number can be one or a plurality of side-by-side devices.

Disclosed as an example of the closed space 10 is a greenhouse 10a, because the control and regulation of its indoor air by optimizing the growth conditions present a challenging effort. The optimal growth conditions in a greenhouse call for a

temperature of 18-25°C and a relative air humidity of 70-90%. In addition, the carbon dioxide content should be at least 1000 ppm while the normal content of outdoor air is in the order of 350 ppm. Holding the temperature within the optimum, range, especially in the summer (in Finland), presents nowadays a problem - that is dealt with by opening hatches present in the upper part of a greenhouse and by ventilating. Temperature shall drop, but the carbon dioxide content falls also and so does the relative humidity, which is not desirable. The arrangement according to the invention offers an effective and energy-efficient solution to the problem.

The arrangement according to the invention for treating the indoor air of a closed space works basically as follows. The apparatus 1 ; 1 ¹ , 1 ² , 1 ³ is supplied with water, the temperature of which is maintained below a desired greenhouse temperature. In the apparatus' treatment chamber 3, water is sprayed with the water sprayer 4, such that the droplet size is very small and hence the total surface area of water droplets is large indeed. As indoor air is delivered by the fan 6 through the inlet aperture 310 into the treatment chamber 3, such air is forced to turbulent motion and to contact with microscopic droplets, the interaction of air and water being highly effective. Even a small amount of water in a large amount of air functions as an effective regulator of air temperature. Some of the moisture in warm air condenses in cool water, which warms up while the air cools down. The airborne wa- ter below the dewpoint of air condenses in the treatment chamber 3 and drains by way of the receiver 8 and the outlet aperture 81 into the outlet pipe 12 and further into the water storage 15. Respectively, water evaporates from warm water into cooler (and dry) air, water cools down and air warms up.

Whenever the arrangement according to the invention makes use of the equip- ment 1 ; 17 for controlling and regulating the temperature of water, i.e. the water temperature regulating device 1 ; 17 ¹ , 17 ² , as specifically depicted in fig. 14, such equipment works as follows. Dry outdoor air, which is delivered by the fans 6 of the device 1 ; 17 from the inlet aperture 310 into the treatment chamber 3, receives evaporation of water sprayed from the water sprayer 4, i.e. water coming from the apparatus units 1 ; 1 ¹ , 1 ² , 1 ³ of the greenhouse 10a (preferably flowing gravitation- ally downward along the outlet pipes 13; 13 ¹ , 13 ² , 13 ³ or the like), whereby most of the water condenses (only a fraction evaporates). This condensed water is returned from the water temperature regulating devices 1 ; 17; 17 ¹ , 17 ² to the water storage 15 along the pipe 13; 13 ⁴² . The arrangement according to the invention, in one of its preferred embodiments making use of the water temperature regulating device 17 ¹ , 17 ² , comprises a by-

pass flow system 18, including a bypass pipe 18a and a control valve 18b (sketched in dashed lines in fig. 11 ). This enables controlling the temperature of circulated water and at least the effectiveness of its cooling by opening and closing the valve 18b and the amount of water flowing through the pipe 18a. The arrangement according to the invention, in one of its preferred embodiments making use of the water temperature regulating device 1 ; 17; 17 ¹ , 17 ² , a water receiver 8; 80, which is common to all temperature regulating devices and, in addition, relatively large in volume. In this case, the water storage 15 is not absolutely necessary and can even be omitted from the arrangement. Thus, the water re- ceiver 8; 80 functions the same way as a water storage. The pump 14 (or alternatively a pump 14 ¹ , 14 ² , 14 ³ dedicated for each treatment apparatus 1 ; 1 ¹ , 1 ² , 1 ³ , fig. 14) is hence linked with a pipe connected from the suction side to the water receiver 8; 80 of the temperature regulating devices 1 ; 17; 17 ¹ , 17 ² , as sketched in dashed lines in fig. 14. A space, especially a closed space 10, 10a, 10b, can also be provided, if necessary, with a separate ventilation for drawing replacement air into the space from its surroundings. This is inevitable e.g. in greenhouses 10a, wherein extra carbon dioxide is produced by burning natural gas or the like, as otherwise the indoor air shall be enriched with nitrogen oxides and other toxic gases. A space ventilation system according to the invention is implementable by means of an apparatus 1 of the invention. The space ventilation system according to the invention comprises at least two apparatus units 1 ; 1 ⁴ , 1 ⁵ for bringing air and water into a mutual interaction. The first apparatus is adapted to treat indoor air and to expel it outside a space and the second apparatus is adapted to treat ambient air outside the space and to convey it inside the space. The first and second apparatus units have the water supply and discharge systems 5; 8, 82 thereof coupled with each other for circulating water therebetween either directly or by way of a suitable water storage 54. The circulation water lends itself to purification and/or replacement as necessary. An advantage gained by the space ventilation system according to the invention is that the circulation water can be used for treating the expulsion-ready or outgoing indoor air e.g. for recovering therefrom heat and/or possibly harmful ingredients, such as gases (e.g. ammonia from production facilities of poultry or other livestock) or particles, the spreading of which in the environment is not desirable.

In a preferred option of ventilation, use is made of two, first and second devices 1 ; 1 ⁴ , 1 ⁵ , such as the apparatus shown in figs. 1-3. Reference is made to fig. 15. In the first device 1 ; 1 ⁴ , the inlet air is drawn from a closed indoor space 10; 10b and delivered by a fan through an inlet aperture 310; 310 ¹ into the treatment chamber and further by way of an outlet channel and an outlet aperture 320; 320 ¹ out of the space 10; 10b. The inlet air is treated, especially cooled down, in the treatment chamber by means of water mist produced by a water sprayer. At this point, the temperature of feed water has been adjusted to a preferred proper value, i.e. to be lower than the temperature of the indoor space. Thus, heat is absorbed by feed water into the water from air passing through the device 1 ; 1 ⁴ . In the second device 1 ; 1 ⁵ , the inlet air is drawn from the environment surrounding the space 10; 10b and delivered by a fan through an inlet aperture 310; 310 ² into the treatment chamber and further by way of an outlet channel and an outlet aperture 320; 320 ² into the indoor space 10; 10b. The inlet air is treated, such as heated (and humidi- fied), in the treatment chamber by means of water mist produced by a water sprayer. Thus, the temperature of feed water is appropriately high to enable a transfer of heat from the water to the air about to be delivered into the space 10; 10b. The water is most preferably adapted to circulate from the first device 1 ; 1 ⁴ , from its receiver, along an outlet pipe 82; 82 ¹ to the second device 1 ; 1 ⁵ , i.e. to. a feed pipe 50; 50 ² of its water supply system, preferably gravitationally. The water is further circulated by way of a receiver and an outlet pipe 82; 82 ² (and preferably a water storage 54 and a possible water temperature regulating system) of this second device by means of a pump 53 back to the first device 1 ; 1 ⁴ , in other words, by way of its water supply system 5; 50 ¹ to its water sprayer. Accordingly, the water circulates by way of the first and second devices 1 ; 1 ⁴ , 1 ⁵ and functions as a heat recovery and transfer medium.

The first and second devices 1 ; 1 ⁴ , 1 ⁵ are most preferably mounted in the immediate vicinity of a closed space wall 19, whereby all that is needed are penetration holes through the wall for those outlet apertures which are in communication with the exterior of the space 10; 10b. The proposed ventilation system is also applicable for treating the indoor air expelled from the space to clear it of particles and/or gases (odors), e.g. in the context of livestock shelters. These remove themselves into water mist or circulation water, which latter must in this case be purified or at least replaced at appropriate intervals. Alternatively, the indoor air expelled from a space can be delivered by way of a suitable connecting pipe into an underground pipe network, from which it is impregnated into the subsoil, e.g. into the subsoil of a greenhouse or the like. This makes it possible to utilize e.g. ammonia-bearing

indoor air, expelled from livestock shelters, directly for soil improvement purposes, i.e. for nitrogen fertilization (nitrogen salts).