Buried box system with intelligent environmental control

Abstract

The buried box system with intelligent environment control comprises a humidity control device, at least one combustible gas sensor and a fresh air device. The humidity control device is arranged inside the system and comprises at least one humidity sensor for sensing the humidity of the air inside the system and at least one heating module which starts to work to heat the air inside the system when the humidity of the air inside the system reaches a preset humidity threshold. The at least one combustible gas sensor is configured to sense the combustible gas concentration inside the system. The fresh air device comprises a fan arranged inside the system and an air inlet and an air outlet which are communicated with the space inside the system and the external environment. When the at least one humidity sensor senses that the humidity of the air inside the system reaches the humidity threshold and / or when the at least one combustible gas sensor senses that the combustible gas concentration inside the system reaches a concentration threshold, the fan starts to work to increase the circulation of the air inside the system to the external environment through the air outlet.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of buried boxes, and more particularly, to a buried box system with intelligent environment control. BACKGROUND

[0002] Buried boxes have been widely used in the field of storage of environmental sanitation garbage and other articles. Generally, a buried box includes a top wall, a bottom wall and a plurality of side walls, and an openable top cover is arranged in the top wall to load fillers into the interior of the buried box. In use, the buried box is buried in the ground with the top wall exposed to the external environment. In order to enhance the ventilation of the buried box, a non-powered wind ball scheme has been developed, in which a non-powered wind ball device including a turbine is installed on the top cover of the buried box, and the natural wind power and the temperature difference between the inside and outside of the box cause air thermal convection to push the turbine to rotate, thereby utilizing the centrifugal force and negative pressure effect to discharge the stale or humid air in the box.

[0003] However, the conventional non-powered wind ball scheme has a weak exhaust capacity, resulting in poor air circulation in the relatively closed internal space of the buried box. When the ambient temperature of the box is lower than the dew point temperature, condensate water will be generated in the box, and the humidity of the air in the box will increase. This humid environment can cause the rusting of metal structural parts and the failure of electrical equipment in the box, thereby shortening the service life of the buried box equipment. On the other hand, in the case of poor air circulation, if the cleaning of organic matter in the box is not timely, it can also lead to the generation of flammable gas, such as methane, due to the lack of oxygen or anaerobic environment, forming a hidden carbon source, thus posing a safety hazard to the electrical equipment in the box.

[0004] Therefore, there is a need for a buried box system that can effectively prevent the air humidity and flammable gas concentration in the interior of the box from being too high. SUMMARY

[0005] In order to solve the above-mentioned problems of existing buried boxes in terms of air humidity and flammable gas concentration control in the internal environment, the present application proposes a buried box system with intelligent environment control. By using the buried box system of the present application, real-time sensing of the air humidity and flammable gas concentration in the interior of the buried box system is realized, and when necessary, automatic processing to reduce the air humidity and / or flammable gas concentration is performed, thereby keeping the internal environment of the buried box system dry at all times, reducing the risk of rusting of metal structural parts and failure of electrical elements, and the risk of potential fire and electrical element safety hazards.

[0006] According to one embodiment of the present application, a buried box system includes a top wall, a bottom wall and a plurality of side walls, which bound an internal space of the buried box system. The buried box system further includes a humidity control device, at least one flammable gas sensor and a fresh air device.

[0007] The humidity control device is arranged inside the system and comprises at least one humidity sensor sensing the humidity of the air inside the system and at least one heating module. The heating module starts to work to heat the air inside the system when the humidity of the air inside the system reaches a pre-set humidity threshold. At least one combustible gas sensor is configured to sense the concentration of combustible gas inside the system. The fresh air device comprises a fan arranged inside the system and an air inlet and an air outlet communicating the inner space of the system and the outside environment. Wherein, when the at least one humidity sensor senses that the humidity of the air inside the system reaches the pre-set humidity threshold and / or when the at least one combustible gas sensor senses that the concentration of combustible gas inside the system reaches a pre-set concentration threshold, the fan starts to work to increase the circulation of the air inside the system to the outside environment through the air outlet, thereby further reducing the humidity of the air inside the system and reducing the concentration of combustible gas inside the system.

[0008] The air inlet is closed by the air inlet cover during normal operation of the system, and before starting the fan, the opening state of the air inlet is determined, and only when it is determined that the air inlet can be opened, the air inlet cover is opened to open the air inlet.

[0009] Optionally, in the case where it is determined that the air inlet can be opened, the actuator connected between the air inlet cover and the inner wall of the system is triggered to actuate the air inlet cover to open to the outside environment to open the air inlet.

[0010] Optionally, the air inlet is arranged on the top wall adjacent to the side wall, and the air outlet is arranged on the top cover.

[0011] Optionally, the fan is attached to the top cover by a mounting bracket. And optionally, the at least one humidity sensor and the at least one combustible gas sensor are attached to the mounting bracket.

[0012] Optionally, the at least one heating module is attached to the inside of the side wall adjacent to the bottom wall.

[0013] Optionally, two or more humidity sensors, two or more combustible gas sensors, and two or more heating modules are arranged at different positions inside the ground burial tank system, and as long as one of the humidity sensors senses that the humidity of the air inside the ground burial tank system reaches a pre-set humidity threshold and / or one of the combustible gas sensors senses that the concentration of combustible gas inside the ground burial tank system reaches a pre-set concentration threshold, the start of the fresh air device is triggered.

[0014] Optionally, the ground burial tank system further comprises at least one temperature sensor configured to sense the temperature of the at least one heating module or to sense the temperature of the air inside the ground burial tank system, and when the temperature sensed by the at least one temperature sensor reaches a pre-set temperature threshold, the heating module stops working.

[0015] Optionally, the fan has at least two air supply intensities, and the air supply intensity of the fan is determined according to one or a combination of the following factors when the fresh air device is started: the size of the system, the air humidity value inside the system sensed by the at least one humidity sensor, the combustible gas concentration value inside the system sensed by the at least one combustible gas sensor, and the opening state of the air inlet. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 shows a side view of a buried box system with intelligent environment control according to an embodiment of the present application;

[0017] Figure 2 shows a perspective view of the buried box system as seen along the arrow A-A in Figure 1

[0018] Figure 3 shows a top view of the buried box system as seen along the arrow B in Figure 1

[0019] Figure 4 shows a perspective view of the internal structure of the buried box system as seen with one side wall removed according to an embodiment of the present application;

[0020] Figure 5 shows a perspective view of the internal structure of the buried box system as seen from a different viewing angle than Figure 4

[0021] Figure 6 shows a flow chart of the operation of a buried box system according to an embodiment of the present application.

[0022] LIST OF REFERENCE NUMBERS

[0023] 100 buried box system

[0024] 101 top wall

[0025] 102 side wall

[0026] 103 bottom wall

[0027] 104 top cover

[0028] 105 wiring hole

[0029] 110 humidity control device

[0030] 111 humidity sensor

[0031] 112 heating module

[0032] 120 combustible gas sensor ​​​

[0033] 130 fresh air device

[0034] 131 fan

[0035] 132 air inlet

[0036] 133 air outlet

[0037] 134 air inlet cover

[0038] 135 actuator

[0039] 136 mounting bracket DETAILED DESCRIPTION

[0040] A preferred embodiment of a buried box system with intelligent environmental control according to the present application will be described in detail below with reference to the accompanying drawings.

[0041] Figure 1 A side view of a buried box system 100 with intelligent environmental control according to one embodiment of the present application is shown, and Figure 2 and Figure 3 perspective and top views of the buried box system 100 as seen from arrows A-A and arrows B in Figure 1 respectively. In conjunction with Figures 1-3 , the buried box system 100 comprises a top wall 101, a number of side walls 102 (e.g. four side walls 102) and a bottom wall 103, which walls enclose an interior space of the buried box system 100. Among others, Figures 1-3 It is further shown that the top wall 101 of the buried box system 100 comprises an openable and closable top cover 104, e.g. positioned in the center of the top wall 101, through which top cover 104 objects to be stored can be filled into or taken out of the buried box system 100, and through which the equipment and wiring in the interior space of the buried box system 100 can be observed and maintained.

[0042] Figure 2 It is further shown that a number of wiring holes 105 are provided through the side walls 102 for wiring of equipment inside the buried box system 100 to the outside environment therethrough. The specific wiring of equipment inside the buried box system 100 to the outside environment depends on the arrangement position of each equipment and is not described in detail herein.

[0043] Referring to Figure 2According to the embodiment, the underground box system 100 comprises a humidity control device 110, a combustible gas sensor 120 and a fresh air device 130. The humidity control device 110 comprises a humidity sensor 111 and a heating module 112. The humidity sensor 111 is configured to sense the humidity of the air inside the underground box system 100. Since the density of humid air is less than that of dry air at the same temperature, it is advantageous to arrange the humidity sensor 111 at the upper part of the interior space of the underground box system 100, i.e. close to the top wall 101, because such an arrangement can make it more accurate to sense the humidity condition of the air.

[0044] To avoid the corrosion of the metal structure and the failure of the electrical components inside the underground box system 100 caused by condensation in the interior space of the underground box system 100 when the temperature of the external environment is low, the humidity control device 110 further comprises a heating module 112. When the humidity sensor 111 senses that the humidity of the air inside the underground box system 100 reaches a pre-set humidity threshold, the heating module 112 is triggered to start working to heat the air inside the underground box system 100 to achieve the effect of reducing the humidity of the air. The humidity threshold can be pre-set and adjusted depending on the type of the filler inside the underground box system 100. It is advantageous to arrange the heating module 112 at the lower part of the interior space of the underground box system 100, i.e. close to the bottom wall 103, because such an arrangement can make the air close to the heating module 112 be heated first, and then the hot air rises to promote the heating and dehumidification of the air in the upper space, so that the air in the entire interior space is quickly heated. For example, Figure 2 and Figure 5 The heating module 112 is schematically shown as being arranged inside the side wall 102 close to the bottom wall 103 in

[0045] The heating module 112 can adopt conventional devices for heating air, and it is advantageous to adopt a PTC heating module, which has the advantages of power saving and relative safety.

[0046] A temperature sensor (not shown in the figure) can be further configured in the underground box system 100. The temperature sensor can be attached to the heating module 112 to sense the working temperature of the heating module 112, and if the working temperature reaches a pre-set temperature threshold, the heating module 112 is triggered to stop heating, thereby further ensuring the safety of the working of the heating module 112.

[0047] Alternatively, the temperature sensor can be arranged at other positions in the interior space of the underground box system 100 and configured to sense the air temperature inside the underground box system 100. Also in this case, if the air temperature is sensed to reach a pre-set temperature threshold, the heating module 112 is triggered to stop heating. For example, the temperature sensor can be arranged near the humidity sensor 111.

[0048] When the humidity sensor 111 senses that the air humidity inside the underground tank system 100 reaches a pre-set humidity threshold, in addition to triggering the heating module 112 to heat the air inside the underground tank system 100, the start-up of the fresh air device 130 is also triggered to reduce the air humidity inside the underground tank system 100 through the circulation of the air inside the underground tank system 100 and the air of the external environment. The specific arrangement and operation of the fresh air device 130 will be described in detail later.

[0049] Figure 2 Also shown in FIG. 1 is a combustible gas sensor 120 configured to sense the combustible gas concentration inside the underground tank system 100. In the underground tank for storing, for example, sanitation garbage, the combustible gas that can be generated mainly refers to methane. Therefore, the combustible gas sensor 120 can be a methane sensor. Since the density of methane is less than that of air, it is advantageous to arrange the combustible gas sensor 120 at the upper part of the internal space of the underground tank system 100, i.e., close to the top wall 101, when the combustible gas sensor 120 is a methane sensor, because such an arrangement can make it more accurate to sense the methane concentration in the air.

[0050] To avoid the risk of potential fire and electrical element safety hazards caused by too high combustible gas concentration inside the underground tank system 100, the combustible gas sensor 120 is configured to trigger further operations to reduce the combustible gas concentration when it senses that the combustible gas concentration inside the underground tank system 100 reaches a pre-set concentration threshold.

[0051] Specifically, the reduction of the combustible gas concentration is also achieved through the fresh air device 130. That is, when the humidity sensor 111 senses that the air humidity inside the underground tank system 100 reaches a pre-set humidity threshold and / or when the combustible gas sensor 120 senses that the combustible gas concentration inside the underground tank system 100 reaches a pre-set concentration threshold, the start-up of the fresh air device 130 is triggered.

[0052] Still referring to Figure 2 , the fresh air device 130 includes a fan 131, an air inlet 132 and an air outlet 133. The fan 131 is advantageously attached to the top cover 104 by a mounting bracket 136 and arranged in the internal space of the underground tank system 100 below the top cover 104. Since the side wall 102 and the bottom wall 103 of the underground tank system 100 are buried underground during use, the air inlet 132 and the air outlet 133 of the fresh air device 130 are advantageously provided on the top wall 101 or the top cover 104 to communicate the internal space of the underground tank system 100 and the external environment.

[0053] Figure 2It is shown that the air outlet 133 is arranged on the top cover 104 to open to the outside space, while the air inlet 132 is arranged on the top wall 101 adjacent to the side wall 102. It is advantageous to position the air inlet 132 as far away from the air outlet 133 as possible, because such an arrangement can increase the path of air flow inside the underground box system 100, thereby increasing the exchange of air inside the underground box system 100 with the outside environment air. The air inlet 132 is closed during normal operation of the underground box system 100, but can be opened when needed. Specifically, the air inlet 132 is provided with an air inlet cover 134 that can open and close the air inlet 132, and an actuator 135 is connected between the air inlet cover 134 and the inside of the wall of the underground box system 100, for example, the side wall, thereby controlling the movement of the air inlet cover 134 to open and close the air inlet 132 through the movement of the actuator 135. Figure 2 The actuator 135 is in the form of a telescopic rod, but it can also be other actuators.

[0054] When the humidity sensor 111 senses that the humidity of the air inside the underground box system 100 reaches a pre-set humidity threshold value and / or when the flammable gas sensor 120 senses that the concentration of flammable gas inside the underground box system 100 reaches a pre-set concentration threshold value, the fan 131 of the fresh air device 130 is triggered to start to suck the internal air of the underground box system 100 to the outside environment through the air outlet 133, thereby further reducing the humidity of the air inside the underground box system 100 and reducing the concentration of flammable gas.

[0055] Before the fan 131 starts, it is advantageous to determine the opening state of the air inlet 132, which is completed by an infrared sensor (not shown in the figure) arranged near the air inlet 132, for example, on the top wall 101 in the outside environment. Since the opening of the air inlet 132 requires the actuator 135 to actuate the air inlet cover 134 to open to the outside environment, it is possible that there is an interfering object outside the air inlet cover 134 that cannot be normally opened to the outside environment in the case that the underground box system 100 is buried in the ground. If the actuator 135 is triggered to actuate the air inlet cover 134 to open to the outside environment once the fan 131 starts, it is possible that the air inlet cover 134 cannot be normally opened or even forcibly opened, resulting in damage to the air inlet cover 134 or the actuator 135 or the external object.

[0056] The surrounding environment of the air inlet 132 is sensed by the infrared sensor before the air inlet 132 is opened to determine whether the air inlet 132 can be normally opened. This can avoid the risk of potential damage to the air inlet cover 134 or the actuator 135 or external objects. If the surrounding environment of the air inlet 132 is determined to be free of interfering objects by the infrared sensor, the actuator 135 is triggered to actuate the air inlet cover 134 to open to the external environment. In this case, the start of the fan 131 causes the air in the external environment to flow into the interior of the pit system 100 through the air inlet 132, and the air in the interior of the pit system 100 flows to the external environment through the air outlet 133, thereby achieving the effect of reducing the humidity and the concentration of flammable gas in the air in the interior of the pit system 100 through the exchange of air between the interior and the exterior.

[0057] On the other hand, if the surrounding environment of the air inlet 132 is determined to have interfering objects by the infrared sensor, the actuator 135 is not triggered to actuate the air inlet cover 134 to open to the external environment. In this case, the start of the fan 131 still causes the air in the interior of the pit system 100 to flow to the external environment through the air outlet 133, thereby reducing the humidity and the concentration of flammable gas in the air in the interior of the pit system 100 to some extent, but the rate of air flow is lower than when the air inlet 132 is opened, and the rate of reduction of the humidity and the concentration of flammable gas in the air in the interior of the pit system 100 is also relatively low.

[0058] Advantageously, the fan 131 has at least two air supply intensities. The air supply intensity of the fan 131 when the fresh air device 130 is started is determined according to one or a combination of the following factors: the size of the pit actually used, the sensed humidity value and flammable gas concentration value of the air in the interior of the pit system 100, and the opening state of the air inlet 132. Specifically, in the case where the size of the pit actually used is small, the sensed humidity value and / or flammable gas concentration value of the air in the interior of the pit system 100 exceeds the pre-set humidity threshold value and / or concentration threshold value, but the amplitude of the excess is small, and the air inlet 132 can be normally opened, the fan 131 can be set to use a lower air supply intensity. Conversely, in the case where the size of the pit actually used is large, the sensed humidity value and / or flammable gas concentration value of the air in the interior of the pit system 100 exceeds the pre-set humidity threshold value and / or concentration threshold value, but the amplitude of the excess is large, and the air inlet 132 cannot be normally opened, the fan 131 can be set to use a higher air supply intensity, thereby increasing the rate of reduction of the humidity and the concentration of flammable gas in the air in the interior of the pit system 100. Depending on actual needs, the fan 131 can have three, four, or even more different air supply intensities.

[0059] In addition, although only one humidity sensor 111, one combustible gas sensor 120 and one heating module 112 are shown in each figure, depending on the size of the actual underground box, the arrangement of the filling inside the underground box, and other factors, more than one humidity sensor 111, more than one combustible gas sensor 120 and more than one heating module 112 can be provided. Specifically, two or more humidity sensors 111, combustible gas sensors 120 and heating modules 112 can be arranged at different positions inside the underground box system 100, and as long as one of the humidity sensors 111 senses that the air humidity inside the underground box system 100 reaches a pre-set humidity threshold and / or one of the combustible gas sensors 120 senses that the combustible gas concentration inside the underground box system 100 reaches a pre-set concentration threshold, the start of at least one heating module 112 and / or the fresh air device 130 is triggered.

[0060] Also, more than one temperature sensor can be provided. Specifically, one temperature sensor can be provided at the heating module 112 to sense the temperature of the heating module 112, while another temperature sensor is provided at other positions to sense the air temperature inside the underground box system 100, and as long as the temperature sensed by one of the temperature sensors reaches its pre-set temperature threshold, the heating module 112 is stopped from working.

[0061] Figure 4 and Figure 5 Perspective views showing the internal configuration of the underground box system 100 from different viewing angles in the case of removing one side wall of the underground box system 100 are shown respectively. Figure 4 More details of the fan 131 are shown. In this embodiment, the fan 131 is attached to the top cover 101 through a mounting bracket 136. At least one humidity sensor 111, at least one combustible gas sensor 120 and at least one temperature sensor can also be attached to the top cover 101 through the mounting bracket 136. Since the top cover 101 can be conveniently opened from the outside, such an arrangement simplifies the wiring design on the one hand, and facilitates observation and maintenance of the internal equipment on the other hand.

[0062] The operation flow of the underground box system 100 with intelligent environment control according to the present application is described below in connection with Figure 6

[0063] First, the system 100 is powered on, the at least one humidity sensor 111 senses the air humidity inside the underground box system 100, and the at least one combustible gas sensor 120 senses the combustible gas concentration inside the underground box system 100;

[0064] ​If the at least one humidity sensor 111 senses that the air humidity inside the buried box system 100 reaches the pre-set humidity threshold value, the heating module 112 is triggered to work and the infrared sensor is triggered to detect the air inlet 132 to determine whether the air inlet 132 can be normally opened, the heating module 112 heats the air inside the buried box system 100, and when the at least one temperature sensor senses that the temperature reaches the pre-set temperature threshold value, the heating module 112 stops working;

[0065] If the at least one combustible gas sensor 120 senses that the combustible gas concentration inside the buried box system 100 reaches the pre-set concentration threshold value, the infrared sensor is also triggered to detect the air inlet 132 to determine whether the air inlet 132 can be normally opened;

[0066] If it is determined that the air inlet 132 can be normally opened, the actuator 135 is triggered to actuate the air inlet cover 134 to open to the external environment to open the air inlet 132, and the fan 131 is opened at the determined air supply intensity, and under the action of the fan 131, the air inside the buried box system 100 flows with the external environment air to further reduce the air humidity inside the buried box system 100 and the combustible gas concentration inside the buried box system 100;

[0067] If it is determined that the air inlet 132 cannot be normally opened, the actuator 135 is not triggered to actuate the air inlet cover 134 to open to the external environment, and the air inlet 132 remains closed, and the fan 131 is opened at the determined air supply intensity, and under the action of the fan 131, the air inside the buried box system 100 flows with the external environment air through the air outlet 133 to further reduce the air humidity inside the buried box system 100 and the combustible gas concentration inside the buried box system 100.

[0068] In summary, by using the buried box system with intelligent environment control of the application, the air humidity and the combustible gas concentration inside the buried box system can be sensed in real time when the buried box system is powered on, and when the air humidity and / or the combustible gas concentration reaches the pre-set humidity threshold value and / or the pre-set concentration threshold value, the air humidity and / or the combustible gas concentration can be automatically reduced, thereby keeping the internal environment of the buried box system dry at all times, reducing the risk of corrosion of metal structural parts and failure of electrical elements inside the buried box system, and the potential risk of fire and electrical element safety hazards.

[0069] The above has described in detail, with the aid of the drawings, possible but non-limiting embodiments of a buried box system with intelligent environmental control according to the present application. Modifications and supplements to the technique and structure, as well as re-combinations of features in the various embodiments, which are obvious to a person skilled in the art without departing from the scope and the essence of the present disclosure as set out in the following claims, are obviously to be considered as included within the scope of the present application. These modifications and supplements, which are conceivable within the teaching of the present application, are therefore to be considered as part of the present disclosure. The scope of the present disclosure is defined by the following appended claims and includes equivalent techniques known at the filing date of the present disclosure and equivalent techniques not yet foreseen.

Claims

1. A buried box system (100) with intelligent environment control, comprising: a humidity control device (110) arranged inside the system (100) and comprising: at least one humidity sensor (111) configured to sense the air humidity inside the system (100), and at least one heating module (112) starting to work when the at least one humidity sensor (111) senses that the air humidity inside the system (100) reaches a pre-set humidity threshold, to heat the air inside the system (100); at least one combustible gas sensor (120) configured to sense the combustible gas concentration inside the system (100); and a fresh air device (130) comprising a fan (131) arranged inside the system (100) and an air inlet (132) and an air outlet (133) communicating the internal space of the system (100) and the external environment, wherein the fan (131) is started to increase the circulation of the air inside the system (100) to the external environment through the air outlet (133) when the at least one humidity sensor (111) senses that the air humidity inside the system (100) reaches the humidity threshold and / or when the at least one combustible gas sensor (120) senses that the combustible gas concentration inside the system (100) reaches a pre-set concentration threshold, wherein the fan (131) has at least two air supply intensities, wherein the air supply intensity of the fan (131) when the fan (131) is started is determined according to one or a combination of the following factors: the size of the system (100), the air humidity value inside the system (100) sensed by the at least one humidity sensor (111), the combustible gas concentration value inside the system (100) sensed by the at least one combustible gas sensor (120), and the opening state of the air inlet (132), wherein the air inlet (132) is closed by an air inlet cover (134) during normal operation of the system (100), and the periphery environment of the air inlet (132) is sensed by an infrared sensor before starting the fan (131) to determine whether the air inlet (132) can be normally opened, and the air inlet cover (134) is opened to open the air inlet (132) when it is determined that the air inlet (132) can be opened.

2. The system (100) according to claim 1, wherein the system (100) comprises a top wall (101), a side wall (102) and a bottom wall (103), the top wall (101) comprises an openable and closable top cover (104), and the fan (131) is attached to the top cover (104) by a mounting bracket (136).

3. The system (100) according to claim 2, wherein the air inlet (132) is arranged on the top wall (101) adjacent to the side wall (102), and the air outlet (133) is arranged on the top cover (104).

4. The system (100) as claimed in claim 2, wherein the at least one humidity sensor (111) and the at least one flammable gas sensor (120) are attached to the mounting bracket (136).

5. The system (100) as claimed in claim 2, wherein the at least one heating module (112) is attached inside the side wall (102) adjacent to the bottom wall (103).

6. The system (100) as claimed in any one of claims 1 to 5, wherein the system (100) further comprises at least one temperature sensor configured to sense the temperature of the at least one heating module (112), and the at least one heating module (112) stops working when the at least one temperature sensor senses that the temperature of the at least one heating module (112) reaches a pre-set temperature threshold.

7. The system (100) as claimed in any one of claims 1 to 5, wherein the system (100) further comprises at least one temperature sensor configured to sense the air temperature inside the system (100), and the at least one heating module (112) stops working when the at least one temperature sensor senses that the air temperature reaches a pre-set temperature threshold.

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