greenhouse

Abstract

The present invention relates to a greenhouse (1) having a roof (2), a floor (3), two end walls (4) and two side walls (5). Along one of the end or side walls (4, 5) there is an elongated mixing space (6) adjacent to an elongated space for conditioned air (7). The mixing space (6) is fluidly connected to the exterior (10) of the greenhouse and to the growing space by one or more openings (11). The mixing space (6) and the space for conditioned air (7) are fluidly connected via one or more water pads (12) and via a parallel bypass flow path (B). The growing space (8) comprises a plurality of parallel ventilation conduits (13), each conduit (13) having an air inlet (14) fluidly connected to the space for conditioned air (7).

Description

[Technical field]

[0001] The present invention relates to a greenhouse having an elongated space along one of the greenhouse walls for conditioned ambient and / or greenhouse recirculated air, the elongated space being separated from a growing space of the greenhouse, the growing space being provided with a plurality of parallel ventilation conduits with the conduits fluidly connected to the elongated space. [Background technology]

[0002] Such greenhouse designs are well known and are commonly referred to as semi-enclosed greenhouses. One of the first greenhouses constructed according to this principle was the semi-enclosed greenhouse built in 2005 in Van der Lans, Rilland, The Netherlands. The greenhouse has an elongated space extending along the gable wall at its lower end. The space is provided with a closable window to allow ambient air to enter the space, and a closable valve at the upper end of the elongated space to allow air from the growing compartment to enter the space. The elongated space itself is provided with an indirect heat exchanger to heat or cool the temperature of the ambient air, recirculated air, or a mixture thereof.

[0003] WO 2008 / 002686 describes a greenhouse with an air gap in the end wall where ambient air and / or greenhouse recirculation air is collected and distributed to the growing compartments via a number of parallel ventilation tubes. A heat exchanger may be present at the inlet of a fan which draws air into the ventilation tubes to cool or heat it. According to this publication, the interior of the greenhouse can be cooled by drawing in ambient air through a pad cooling system located at the ambient air inlet in the end wall and distributing this air through the ventilation tubes.

[0004] JP 2015-6133 A describes a greenhouse with an empty space in the end wall, in which ambient air and / or greenhouse recirculated air is collected and distributed to the growing compartments via a number of parallel ventilation pipes. The ambient air is optionally mixed with the greenhouse recirculated air and passed through a water pad before being distributed to the growing compartments. If necessary, the greenhouse recirculated air may be mixed with the air that has passed through the water pad before being distributed to the growing compartments.

[0005] Controlling the climate in a greenhouse by using ambient air and greenhouse recirculated air has been known for many years and is described, for example, in U.S. Pat. No. 3,404,618, issued in 1968. This publication describes ventilation ducts that distribute ambient air and recirculate greenhouse air or combine in the growing area of ​​the greenhouse. At night, only the greenhouse air is recirculated and heated by an open flame. During the day, as the air in the greenhouse rises due to solar radiation, cooler ambient air is drawn in and combined with the recirculated greenhouse air. Maximum cooling is achieved by introducing only ambient air without recirculating air. Additional cooling can be achieved by drawing the air through a water-cooled pad.

[0006] WO 2017 / 176114 describes a greenhouse in which the ambient air is cooled by first contacting the air with liquid water to obtain a cooled and saturated air stream in an evaporative pad. This air stream is subsequently contacted with an aqueous solution of 1,2-propanediol to dry the air. The dry air is contacted with water to obtain cooled air. This cooled air is distributed to the growing compartments via ventilation pipes. The problem with this process is its complexity.

[0007] A drawback of the prior art process using water pads is that air with up to 100% water saturation can be obtained. Such high saturation is preferably avoided as it can cause wear on the ventilation equipment used to draw the air into the ventilation tubes. This can be mitigated by subsequently heating this air stream. However, if cold air is needed to cool the air in the greenhouse growing space, subsequent heating of the air is not preferred. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] International Publication No. 2008 / 002686 [Patent Document 2] JP 2015-6133 A [Patent Document 3] U.S. Pat. No. 3,404,618 [Patent Document 4] International Publication No. 2017 / 176114 Summary of the Invention [Problem to be solved by the invention]

[0009] The object of the present invention is to provide a greenhouse that does not have the drawbacks of the greenhouses of the prior art. This is achieved by a greenhouse which: [Means for solving the problem]

[0010] A greenhouse having a roof, a floor, two end walls, and two side walls, wherein an elongated mixing space is present along one of the end walls or the side walls and disposed adjacent to an elongated space for conditioned air, the mixing space and the space for conditioned air being separated from a growing space present within the greenhouse; the mixing space is fluidly connected to an exterior of the greenhouse by one or more openings for ambient air and to the growing space by one or more openings; The mixing space and the space for conditioned air are fluidly connected via one or more water pads and via parallel air flow paths, the water pads being arranged in parallel with the parallel air flow paths; A greenhouse wherein the growing space includes a plurality of parallel ventilation ducts, each duct having an air inlet with a ventilator, the air inlet being fluidly connected to the conditioned air space.

[0011] The applicants have found that the presently claimed greenhouse can better condition the air as it is distributed by the ventilation ducts. In addition to being able to mix ambient air with air from the growing compartment to obtain the supply air, they have the additional option of further processing this supply air into conditioned air with the desired humidity. Air formed in the water pad with too high humidity may now be mixed with air from the parallel air flow path. This air bypasses the water pad. In this way, excess humidity may be reduced, for example, by the sensible heat of the warm recirculated air from the growing compartment. This results in a more energy-efficient climate control. The greenhouse design further allows for careful control of the humidity of the air distributed through the ventilation ducts.

[0012] Therefore, the present invention also relates to the following process: A process for controlling temperature and / or humidity in a greenhouse comprising a growing space and a separate mixing space, comprising the following steps: (a) collecting ambient air and air from the growing space in a separate mixing space to obtain supply air; (b) contacting a portion of the supply air directly with liquid water to adiabatically cool the mixed air to obtain moist air, while another portion of the supply air is not directly contacted with the liquid water to obtain bypass air. (c) mixing the moist air with the heated air to obtain conditioned air and discharging the conditioned air to the growth space.

[0013] The greenhouse may have a gabled or arched roof. A gabled or arched roof runs parallel to the side walls from one end wall to the other end wall. In other words, the purlins of these roof types run parallel to the side walls. The walls and roof may comprise glass panels or plastic foil. Preferably, the greenhouse has a rectangular shape or plan, and the end walls, also called end gables, are connected perpendicularly to the side walls. In the context of the present invention, two or more greenhouses according to the present invention may be placed adjacent to each other and share side or end walls.

[0014] Along one of the end or side walls, there is an elongated mixing space arranged adjacent to the elongated space for conditioned air. The mixing space may be arranged next to and / or above the space for conditioned air. The mixing space is preferably present in at least the upper half of the greenhouse. The mixing space is suitably separated from the growing space by an inner wall, which may be a transparent wall. In this inner wall, there are one or more openings that fluidly connect the growing space with the mixing space. These openings are preferably at a height higher than the maximum height of the cultivars growing in the growing space. This allows the air above the cultivars to flow approximately horizontally towards these one or more openings in the inner wall. The openings are semi-closable. Semi-closable here means that the openings cannot be closed 100% so that some air always flows from the growing compartment to the mixing space. Such semi-closable openings may be closable curtains made of gas-permeable material or may be flaps that cannot completely close the opening due to programmed limitations in the control software or due to mechanical obstructions. The semi-enclosed opening may be designed so that at least 1 part by volume of air from the grow space enters the mixing space for every 20 parts by volume of ambient air that enters the mixing space.

[0015] The opening for the ambient air is semi-closable. Semi-closable here means that the opening cannot be closed 100% so that some ambient air always flows into the mixing space. Such a semi-closable opening may be a closable curtain made of a gas-permeable material, or a flap that cannot completely close the opening due to programmed limitations in the control software or due to mechanical obstructions. The semi-closable opening may be designed so that at least 1 volume part of ambient air enters the mixing space for every 20 volume parts of air entering the mixing space from the growing compartment.

[0016] The parallel air flow paths may be formed by one or more openings between the mixing space and the space for conditioned air. This opening does not comprise a water pad. At the upstream end of the conduit, or otherwise at its inlet, there is suitably a ventilation device. By operation of this ventilation device, the pressure in the space for conditioned air becomes lower than the pressure in the mixing space, resulting in a positive air flow from the mixing space through the water pad and through the parallel air flow paths to the space for conditioned air. The ratio of air flowing through the water pad and the parallel air flow paths may therefore be influenced by the size of these openings or openings. The size of the openings may be influenced by louvers. Preferably, this ratio is influenced by air displacement means present in the bypass air flow paths. By controlling these air displacement means, suitably ventilation devices, the flow of air flowing through the parallel air flow paths can be controlled.

[0017] Furthermore, the parallel air flow paths preferably comprise one or more heating units. These heating units may be indirect heat exchange units, for example shell-and-tube heat exchange units, in which a heating fluid, e.g. water, flows through a tube and air flows on the so-called shell side of the heat exchanger. The flow and / or temperature of the heating fluid are preferably controllable. In this way, an optimal volume of bypass air with an optimal temperature can be obtained, so as to obtain a desired volume of conditioned air with a desired temperature and humidity.

[0018] The mixing space is fluidly connected to the outside of the greenhouse by openings for the ambient air. These openings may be present in the end or side walls along which the elongated mixing space is present. In such an embodiment, each end or side wall defines a mixing space. The location of these one or more openings in the end or side wall may be at the lower end of the end or side wall, more preferably at the same height as the one or more openings in the above-mentioned inner wall or above the height of the one or more openings in the above-mentioned inner wall. Even more preferably, the openings for the ambient air of the mixing space to the outside of the greenhouse are roof openings. This is advantageous since it allows two adjacent greenhouses according to the invention to be placed close to each other. In the most extreme embodiment, the end or side wall along which the elongated mixing space of each greenhouse is placed may be shared between both greenhouses. This allows a combination of several greenhouses provided with mixing spaces according to the invention into a multi-compartment greenhouse with several non-fluidically connected mixing spaces.

[0019] The growing space is preferably provided with openings for exhausting air from within the growing compartment to the outside of the greenhouse. The need for such openings can be understood when realizing that ambient air is drawn into the growing space via multiple parallel ventilation ducts. Without these openings, pressure would build up and damage the glass or plastic covered greenhouse walls and roof. These openings may be closable windows in the preferred gable or arched roof. Alternatively, these openings may be present in the purlin of the preferred gable roof as described in the applicant's patent application WO 2019 / 125169.

[0020] The growing space comprises a plurality of parallel ventilation conduits. The ventilation conduits are suitably positioned directly above the greenhouse floor in the growing space. The conduits are suitably positioned below the cultivation trough in which the plants grow. The conduits are provided with air outlet openings along their length. The conduits can have any design, for example with a circular or semicircular cross section. Preferably, the conduits are tubes. Such ventilation tubes are well known and are used in many greenhouses, such as the aforementioned semi-closed greenhouse construction in Van der Lans, Rilland, The Netherlands. The ventilation tubes may comprise an inner tube to form an annular space of equal static pressure that promotes uniform outflow of air through one or more rows of openings arranged along the length of the tube. Alternatively, the conduits can be combined with the cultivation trough, as described in the applicant's patent application WO 2019 / 185503.

[0021] The elongated mixing space is along one of the end wall or the side wall and is arranged adjacent to the elongated space for conditioned air. Preferably, the mixing space is along the entire end wall such that the mixing space is defined by the end wall and a portion of the opposing side wall, and each end of the space or mixing space is along the entire side wall such that the mixing space is defined by the side wall, a portion of the end wall and each end of the mixing space. Preferably, the mixing space and the space for conditioned air are each a single space. This is advantageous as a more uniform climate control can be achieved.

[0022] The upper end of the mixing space may be defined by an internal roof portion. Preferably, the upper end of the mixing space is defined by the roof, for example when the opening of the mixing space to the outside of the greenhouse for ambient air is a roof opening. The mixing space is further defined by an end wall or a side wall, depending on which wall the elongated mixing space is located along. The end wall or side wall also includes any internal wall located adjacent to the end wall or side wall. The mixing space is also defined by a substantially vertical partition wall spaced apart from the end wall or side wall and extending substantially parallel to the end wall or side wall. The distance between the greenhouse wall and this partition wall may be 1-5 m, for example in the situation where the mixing space extends along the side wall of a greenhouse with a gable roof, it may span a single gable roof. The mixing space is further defined by a floor or a substantially horizontal high partition floor spaced apart from the floor. The embodiment in which the lower end of the mixing space is a floor is advantageous because it is simple and requires little support structure for the elevated partition floor and pads, as will be explained in more detail below.

[0023] The advantage of having a high floor is that an emergency escape route can be provided within the greenhouse from the growing area to the conditioned air space. In such an embodiment, devices such as pads and heating units are much less likely to be located on the greenhouse floor, thereby forming an emergency route for personnel from the growing area to the conditioned air space, which route is free of obstructions. Thus, the conditioned air space is suitably defined by a generally horizontal high partition floor, an end wall or side wall depending on how the mixing space is located along which wall, and a generally vertical partition wall spaced apart from the end wall or side wall. This partition wall may be located in the same vertical plane as the mixing space partition wall, or in a different vertical plane. The high partition floor is suitably spaced apart from the floor by at least 2m, thereby allowing sufficient head space for the emergency route. The vertical partition wall of the conditioned air space may be provided with a number of emergency doors forming part of the emergency route from the growing space to the conditioned air space.

[0024] The air inlets of the plurality of parallel ventilation ducts are fluidly connected to a vertical interior wall of the conditioned air volume by a ventilation device.

[0025] The mixing space and the space for conditioned air are fluidly connected via one or more water pads. These pads are appropriately vertically arranged wetting screens, also called evaporation pads, in which the water flows from its upper end to its lower end and the air passes through the screen in a substantially horizontal flow direction. The vertical wetting screen has an inlet side for air fluidly connected to the mixing space and an outlet side for air fluidly connected to the space for conditioned air. The air comes into direct contact with the water in the pads, as a result of which a part of the liquid water evaporates. This results in a decrease in the temperature of the air and an increase in the gaseous water in the air. Such cooling is also called adiabatic cooling.

[0026] The mixing space and the space for conditioned air are also fluidly connected via one or more indirect heating units. The pads are arranged in parallel with the one or more indirect heating units, so that a portion of the air from the mixing space is cooled as it passes through the one or more pads, and another portion of the air is increased in temperature as it passes through the one or more indirect heating units.

[0027] The above-mentioned vertical wetting screen may be arranged on a floor or partition floor. The wetting screen preferably extends over 80% of the length of the elongated mixing space. The wetting screen or the wall comprising the vertical screen has an elongated upper end, to which a roof section is preferably connected. The roof section is also connected to the vertical partition wall of the mixing space and comprises one or more indirect heating units. The one or more heating units have an inlet side for air fluidly connected to the mixing space and an outlet side for air fluidly connected to the space for conditioned air. The roof section may be arranged at an angle or horizontally.

[0028] In step (a) of the process according to the invention, the ambient air and the air from the growing space are collected in a separate mixing space to obtain the air supply. When a greenhouse is used with the aforementioned semi-closable openings for the ambient air and the air from the growing space, there is a situation where the ambient air and the air from the growing space are always collected in the mixing space. The volume of the ambient air and the air collected from the growing space depends on the area of ​​the openings. By controlling this area, it is possible to control the relative and absolute volumes of the ambient air and the air from the growing compartments collected in the mixing space. The absolute volume is also suitably controlled by the negative pressure generated in the mixing space by the air displacement means that moves the air from this space to the growing compartments.

[0029] In step (b), a portion of the supply air is brought into direct contact with liquid water to adiabatically cool the mixed air in order to obtain moist air. The resulting air may have a relative humidity of more than 85%, typically 90-95%.

[0030] In step (b), the temperature of the supply air that is not in direct contact with the liquid water may be suitably increased in temperature before performing step (c), as also described above. The desired temperature increase may depend, for example, on the temperature and humidity of the supply air, the volume of the bypass air, the volume of the air to be adiabatically cooled, and the desired temperature and humidity of the conditioned air suitable for conditioning the air in the growing compartment. For example, if a large volume of supply air flows through the parallel air flow paths, less heating or no heating may be required, whereas if a smaller volume is used, more heating may be required. The relative humidity of the conditioned air may vary and may depend, for example, on the type of cultivation in the growing compartment, the time of cultivation and the moment of the day.

[0031] In step (c), the moist air and the heated air are mixed to obtain conditioned air, which is then exhausted to the growing space, preferably via a plurality of parallel ventilation ducts as described above.

[0032] The separate mixing space is preferably a continuous space extending along an end or side wall of the rectangular greenhouse. More preferably, the space extends along the entire end or side wall or at least 80% of its length. The rectangular greenhouse suitably has a roof, a floor, two end walls and two side walls, and the mixing space is defined by a portion of the greenhouse roof, the end or side wall and a vertical partition wall spaced from the end or side wall and extending generally parallel to the end or side wall. The mixing space is further defined by a floor or a generally horizontal elevated partition floor spaced from the floor. Ambient air enters the mixing space through one or more openings in the end or side wall and / or preferably the roof. Air from the growing space enters the mixing space through one or more openings in the partition wall.

[0033] The greenhouse preferably comprises a conditioned air space beneath a generally horizontal elevated partition floor. In step (c), the conditioned air is suitably exhausted to the growing space through a plurality of parallel ventilation ducts within the growing space, the ventilation ducts having conditioned air inlets fluidly connected to the conditioned air space.

[0034] The present invention will be explained with reference to the following FIGS. [Brief description of the drawings]

[0035] [Figure 1] FIG. 1 shows a cross-section of a greenhouse having a gable roof and floor. [Diagram 2] FIG. 2 shows an embodiment of a greenhouse in which the mixing space is present along the entire end wall comparable to the greenhouse of WO 2008 / 002686. [Diagram 3] FIG. 3 is a modification of the greenhouse of FIG. [Figure 4] FIG. 4 is a variation of the greenhouse of FIG. 3, except that the mixing space extends along the end wall. [Diagram 5] FIG. 5 is a three-dimensional view of the greenhouse of FIG. [Figure 6] FIG. 6 shows a greenhouse having a roof, a floor, two end walls and two side walls, a first elongated mixing space and a second elongated mixing space. [Figure 7] FIG. 7 shows a greenhouse similar to that of FIG. 6, except that there are no parallel air flow paths. [Figure 8] FIG. 8 shows a cross-sectional view AA' of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] FIG. 1 shows a cross-sectional view of a greenhouse (1) having a gable roof (2) and a floor (3). An elongated mixing space (6) is present along the entire side wall (5). The mixing space (6) is fluidly connected to the outside of the greenhouse (10) by closable openings (9) for ambient air present in the gable roof (2). These openings (9) may be a single elongated opening that runs along substantially the entire length of the elongated mixing space (6) and the gable roof (2), as shown in FIG. 5. An elongated space for conditioned air (7) is shown located at the lower end of a partition wall (16). At the upper end of this partition wall (16) one or more closable openings (11) are shown that allow air to flow from the growing space (8). The mixing space (6) and the space for conditioned air (7) are separated from the growing space (8). The mixing space (6) and the space for conditioned air (7) are fluidly connected through one or more vertical screens (12) as water pads and through one or more indirect heating units (15) present in the parallel air flow paths (B). Air from the mixing space (6) can flow to the space for conditioned air (7) through two parallel flow paths (A) and (B) as shown. Moist air flowing through the air flow path (A) and heated air in the parallel air flow path (B) are mixed in the space (7) and the resulting conditioned air is distributed to the growing compartments (8) through a number of parallel ventilation ducts (13), as represented diagrammatically by arrows C. The conditioned air enters the ventilation ducts at an inlet (14), where a ventilation device (20) is present.

[0037] The mixing space (6) of Figure 1 is bounded by a portion of the roof (2), side walls (5), a portion of the floor (3), a partition wall (16), and portions of two opposing end walls (4) (as shown in Figure 5). A horizontal roof section (26) is connected to the upper end (24) of the vertical wetting screen (12). The other elongated end of the roof section (26) is connected to the partition wall (16). The roof section (26) comprises one or more indirect heating units (15) having an inlet side (27) for air fluidly connected to the mixing space (6) and an outlet side (28) for air fluidly connected to the space for conditioned air (7).

[0038] Figure 2 shows an embodiment of a greenhouse in which the mixing space (6) is present along the entire end wall (4), comparable to the greenhouse of WO 2008 / 002686. The other symbols have the same meaning as in Figure 1, except for the closable windows (9). These windows (9) in Figure 2 are separate windows present in the row of the gable roof (2).

[0039] Figure 3 is a variation of the greenhouse of Figure 1. The difference is that the mixing space (6) is defined by the roof (2), the side walls (5), a substantially vertical partition wall (16) spaced apart from and extending substantially parallel to the side walls (5), and a substantially horizontal elevated partition floor (17) spaced apart from the floor (3) by at least 2 meters. The conditioned air space (7) is defined by the substantially horizontal elevated partition floor (17), the side walls (5), and a substantially vertical partition wall (18) spaced apart from the side walls (5). The vertical partition wall (18) is provided with a number of emergency doors (19) as part of an emergency escape route, indicated by arrows D, from the growing area to the conditioned air space (7). The doors (19) may be routed down to the floor for easy access. Because the screen (12) and heating unit (15) are positioned higher, an unobstructed emergency path for personnel from the growing section to the conditioned air space is thus provided. The upper side of the partition floor (17) is slightly sloped to allow condensate to flow towards the lower end of the screen (12), where it may be collected in a trough and drained away with the water flowing through the screen.

[0040] FIG. 4 is a variation of the greenhouse of FIG. 3, except that the mixing space (6) extends along the end wall (4).

[0041] Figure 5 is a three-dimensional view of the greenhouse of figure 3. All dimensions are not to scale. For example, the width of a single gable roof section, i.e. the width of the mixing space (6), may be about 4.5 m, while the length of a single ventilation duct (13) may be up to 110 m, so as to be present under 25 gable roof sections (29). The closable openings (9) and the closable openings (11) may extend along the entire length of the side walls (5). Each passage between adjacent ventilation ducts (13) may be provided with an emergency door (19). In this way, workers present in these passages can access the emergency door.

[0042] FIG. 6 shows a greenhouse (30) having a roof (2), a floor (3), two end walls (4) and two side walls (5), and first and second elongated mixing spaces (6a, 6b) that separate first and second growing spaces (8a, 8b) present within the greenhouse (30). The first and second elongated mixing spaces (6a, 6b) run parallel from an end wall (4) to an opposite end wall (4) and suitably share a common wall (32) as shown. The first elongated mixing space (6a) is fluidly connected to the exterior (10) of the greenhouse by an ambient air opening (9a) in the roof (2) and to the first growing space by one or more openings (11a). The second elongated mixing space (6b) is fluidly connected to the outside of the greenhouse (10) by an opening (9b) for ambient air in the roof (2) and to the second growing space by one or more openings (11b). The first growing space (8a) comprises a plurality of parallel ventilation ducts (13a), each duct (13a) having an air inlet (14a) fluidly connected to the first mixing space (6a). The second growing space (8b) comprises a plurality of parallel ventilation ducts (13b), each duct (13b) having an air inlet (14b) fluidly connected to the first mixing space (6b). The elongated mixing spaces (6a, 6b) have the configuration of FIG. 3, with only the conditioned air divider (17) and space (7) shown for clarity. In Figure 6, the first and second elongated mixing spaces (6a, 6b) share a common wall (32) as shown and preferred. Alternatively, there may be a small passageway and / or conditioned air space (7) between the two mixing spaces of the multiple compartment greenhouse (30) for maintaining and accessing the mixing spaces (6a, 6b).

[0043] Figure 7 shows a greenhouse (33) similar to the greenhouse (30) of Figure 6, except that there is no parallel air flow path (B). In this greenhouse, all ambient air and air from the growing spaces (8a, 8b) flows through one or more vertical screens (12a, 12b) that act as water pads. The spaces downstream of these vertical screens (12a, 12b) may be one continuous space for each of the first and second elongated mixing spaces (6a, 6b) and / or may be separate spaces as shown in Figure 8.

[0044] Figure 8 shows the cross section AA' of Figure 7. In the case of the first elongated mixing space (6a), the space downstream of the vertical screen (12a) is a separate space (13a) for each conduit (34a). In the case of the second elongated mixing space (6b), the space downstream of the vertical screen (12b) is one continuous space (34b) fluidly connected to all conduits (13b).

[0045] An advantage of a combined greenhouse according to Figures 6, 7, or 8 is that the unit operations can be closer together than if two separately spaced greenhouses were used. Less area is required for the same area of ​​growing space for a combined greenhouse because no space is required on the sides or ends for ambient air intake.

[0046] Example 1 The greenhouse described in Figures 3 and 5 is simulated, where 35C ambient air (10) and 40% relative humidity are used. The temperature of the air in the growing compartment (8) is 32°C and the relative humidity (RH) is 85%. Further characteristics are listed in Table 1. The control objective in this example is to reduce the temperature of the air in the growing compartment (8) and not increase the relative humidity by obtaining conditioned air in the space (7) and supplying this conditioned air into the growing compartment through the ventilation duct (13).

[0047] The conditioned air of (7) is obtained by first mixing 95 volumes of ambient air (10) in 5 volumes of mixing space (6) to obtain an air supply with a temperature of 34.8C and a relative humidity of 42.1%. 84 volume % of this air supply is contacted with liquid water in the water pad (12) to obtain moist air with a temperature of 25.4C and a relative humidity of 90.2%. The remaining 16 volume % of the air supply bypasses or otherwise avoids the water pad (12) via the parallel air flow path (B) (as in FIG. 1) and is mixed with the moist air to obtain conditioned air with a temperature of 27C and a relative humidity of 79.5%. In this example, the air in the parallel air flow path (B) is not heated. The conditioned air has a lower temperature and a lower relative humidity than the air in the growing compartment and is therefore suitable to reduce the temperature and reduce the humidity in the growing compartment (8) when it is supplied to said growing compartment via the ventilation conduit (13).

[0048] Example 2 Example 1 is repeated, except that the air in the parallel air flow path (B) is heated to increase the enthalpy by about 0.1 kJ / kg. The resulting conditioned air in space (7) has a temperature of 27.1° C. and a relative humidity (RH) of 78.9%. As in Example 1, the conditioned air has a lower temperature than the air in the growing compartment, and an even lower relative humidity, and is therefore suitable to reduce the temperature and reduce the humidity in the growing compartment (8) when supplied to said growing compartment via ventilation conduit (13).

[0049] Comparative experiment This calculated experiment shows how to cool the air of a growing compartment with the same starting conditions as in Examples 1 and 2 in a state-of-the-art greenhouse using the same ambient air of Examples 1 and 2. In this example, the temperature is first reduced by direct contact of the ambient air with liquid water in a water pad to obtain moist air with a temperature of 25.1° C. and a relative humidity (RH) of 89.8%. To reduce the humidity to a value below that of the growing compartment, this moist air is heated to 27.1° C. (equivalent to Example 2) and has a relative humidity of 80%. The amount of energy required for this heating process is about 2 kJ / kg.

[0050] Thus, in the prior art greenhouse, more energy is required to cool the air in the growing compartment of the prior art greenhouse in order to obtain air suitable for supplying to the growing compartment. Furthermore, the humidity of this air is even higher than in Example 2. This comparison shows that the greenhouse and process according to the present invention provide a more energy efficient process for conditioning the interior of the growing space of the greenhouse and air with a lower relative humidity.

[0051] [Table 1]

Claims

1. A greenhouse (1) having a roof (2), a floor (3), two end walls (4) and two side walls (5), an elongated mixing space (6) is arranged along one of the end or side walls (4, 5) adjacent to an elongated space for conditioned air (7), the mixing space (6) and the space for conditioned air (7) being separated from a growing space (8) present in the greenhouse (1); The mixing space (6) is fluidly connected to the outside of the greenhouse (10) by an opening (9) for ambient air and to the growing space by one or more openings (11); The mixing space (6) and the space for conditioned air (7) are fluidly connected via an air flow path (A) passing through one or more water pads (12) and via a parallel air flow path (B) comprising one or more indirect heating units (15), the parallel air flow path (B) being provided with a ventilation device, the water pads (12) being arranged parallel to the parallel flow path (B) such that air from the mixing space (6) can flow into the space for conditioned air (7) via the two parallel flow paths (A) and (B), The greenhouse, wherein the growing space (8) is provided with a plurality of parallel ventilation ducts (13), each duct (13) having an air inlet (14) provided with a ventilation device (20), the air inlet (14) being fluidly connected to the space (7) for conditioned air.

2. 2. The greenhouse according to claim 1, wherein the opening (9) to the outside (10) of the greenhouse for ambient air is a semi-closable opening designed so that at least 1 volume part of ambient air enters the mixing space for every 20 volume parts of air entering the mixing space from the growing compartment.

3. 2. The greenhouse of claim 1, wherein the opening (11) to the growing section (8) of the greenhouse is a semi-closable opening designed to allow at least 1 volumetric part of air from the growing space to enter the mixing space for every 20 volumetric parts of ambient air entering the mixing space.

4. 2. The greenhouse according to claim 1, wherein the opening (9) for the ambient air of the mixing space (6) to the outside (10) of the greenhouse is an opening in the roof (2).

5. 2. A greenhouse according to claim 1, wherein the mixing space (6) and the space for conditioned air (7) are each a single space.

6. 2. The greenhouse of claim 1, wherein the mixing space (6) is defined by a roof (2), an end wall (4) or a side wall (5), a substantially vertical partition wall (16) spaced apart from the end wall (4) or the side wall (5) and extending substantially parallel to the end wall (4) or the side wall (5), and a floor (3) or a substantially horizontal elevated partition floor (17) spaced apart from the floor (3).

7. 7. The greenhouse of claim 6, wherein the conditioned air space (7) is defined by a substantially horizontal elevated partition floor (17), end walls (4) or side walls (5) and a substantially vertical partition wall (18) spaced apart from the end walls (4) or side walls (5).

8. 8. The greenhouse according to claim 7, wherein the elevated partition (17) is spaced at least 2 m from the floor and the vertical partition wall (18) of the conditioned air space (7) is provided with a number of emergency doors (19).

9. 8. The greenhouse according to claim 7, wherein the air inlets (14) of the parallel ventilation ducts (13) are fluidly connected to the vertical partition wall (18) of the conditioned air space (7) by a ventilation device (20).

10. 3. The greenhouse of claim 2, wherein the one or more water pads (12) are arranged on the floor (3) or partition floor (17) and consist of a vertical wetting screen (21) extending along more than 80% of the length of the elongated mixing space (6), the vertical wetting screen (21) having an air (22) inlet side fluidly connected to the mixing space (6) and an air (23) outlet side fluidly connected to the space for conditioned air (7).

11. 11. The greenhouse according to claim 10, wherein a horizontal roof section (26) is connected to the upper end (24) of the vertical wetting screen (21) or to the upper end of the wall comprising the vertical wetting screen (21), the roof section (26) extending up to the vertical partition (16) of the mixing space (6), the roof section (26) being composed of one or more indirect heating units (15) having an inlet side (27) for air fluidly connected to the mixing space (6) and an outlet side (28) for air fluidly connected to the space (7) for conditioned air.

12. A process for controlling temperature and / or humidity in a greenhouse (1) comprising a growing space (8) and a separate mixing space (6), comprising: (a) collecting ambient air and air from a growing space (8) in a separate mixing space (6) to obtain supply air; (b) directly contacting a portion of the supply air with liquid water to adiabatically cool the portion of the supply air to obtain moist air, while another portion of the supply air is not directly contacted with the liquid water and has an elevated temperature prior to performing step (c) to obtain bypass air; (c) mixing the moist air with the bypass air to obtain conditioned air and discharging the conditioned air to the growth space (8).

13. 13. The process according to claim 12, wherein the separate mixing space (6) is a continuous space extending along a side wall (5) or an end wall (4) of the rectangular greenhouse (1).

14. 14. The process of claim 13, wherein the greenhouse (1) has a roof (2), a floor (3), two end walls (4) and two side walls (5), the mixing space (6) being defined by a portion of the roof (2) of the greenhouse (1), the end walls (4) or side walls (5), a vertical partition wall (16) spaced apart from and extending generally parallel to the end walls (4) or side walls (5), and the floor (3) or a generally horizontal elevated partition floor (17) spaced apart from the floor (3), wherein ambient air enters the mixing space (6) through one or more openings (9) in the end or side walls and / or the roof, and air from the growing space enters the mixing space through one or more openings (11) in the partition wall (16).

15. 15. The process according to claim 14, wherein the ambient air enters the mixing space (6) through one or more openings (9) in the roof (2).

16. 15. The process of claim 14, wherein the greenhouse (1) comprises a conditioned air space (7) beneath a substantially horizontal elevated partition floor (17), and in step (c) the conditioned air is exhausted to the growing space (8) via a plurality of parallel ventilation ducts (13) in the growing space (8), the ventilation ducts (13) having conditioned air inlets (14) fluidly connected to the conditioned air space (7).

17. A greenhouse (30, 33) having a roof (2), a floor (3), two end walls (4) and two side walls (5), and first and second elongated mixing spaces (6a, 6b) separating first and second growing spaces (8a, 8b) present in the greenhouse (30); the first elongated mixing space (6a) is fluidly connected to the exterior (10) of the greenhouse by an ambient air opening (9a) in the roof (2) and to the first growing space by one or more openings (11a); the second elongated mixing space (6b) is fluidly connected to the exterior (10) of the greenhouse by an ambient air opening (9b) in the roof (2) and to the second growing space by one or more openings (11b); the first growing space (8a) is provided with a plurality of parallel ventilation ducts (13a), each duct (13a) having an air inlet (14a) fluidly connected to the first mixing space (6a); the second growing space (8b) comprises a plurality of parallel ventilation ducts (13b), each duct (13b) having an air inlet (14b) fluidly connected to the first mixing space (6b); the first and second elongated mixing spaces (6a, 6b) are arranged adjacent to first and second elongated spaces (7a, 7b) for conditioned air, respectively, and the first and second elongated mixing spaces (6a, 6b) and the spaces for conditioned air (7a, 7b) are separated from first and second growing spaces (8a, 8b) present in the greenhouse (1); the first and second elongated mixing spaces (6a, 6b) and the spaces for conditioned air (7a, 7b) are fluidly connected via one or more water pads (12a, 12b) and via parallel air channels (Ba, Bb) equipped with one or more indirect heating units (15), the parallel air channels (Ba, Bb) being provided with ventilation devices, the water pads (12a, 12b) being arranged parallel to a bypass channel (B), each of the plurality of parallel ventilation conduits (13a) of the first growing space (8a) has an inlet (14a) fluidly connected to the first space (7a) for conditioned air (7); A greenhouse (30, 33), wherein each of the plurality of parallel ventilation ducts (13b) of the second growing space (8b) has an inlet (14b) fluidly connected to the second space (7b) for conditioned air.

18. 18. The greenhouse (30, 33) according to claim 17, wherein the first and second elongated mixing spaces (6a, 6b) extend in parallel from one end wall (4) to the opposite end wall (4).

19. 19. The greenhouse (30, 33) according to claim 18, wherein the first and second elongated mixing spaces (6a, 6b) share a common wall (32).

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