FR2875718A1 - Fumigating device e.g. for paper factories includes a ramp with nozzles, a water source, a pump, particle filter, a ultrafiltration and a chamber with UVC ramp including lamps placed in quartz sheaths to destroy the micro-organisms - Google Patents

Abstract

The device comprises: a UV meter (32) is connected to the chamber with ramp, in percentage compared to the intensity of the lamps emitted at the beginning of their lives; automatic cleaning device (34) is connected to the chamber with ramp by scraping to eliminate the deposits formed on the quartz sheaths surrounding the lamps; a three-way electrovalve (22) placed between the source (10) and the filter and another electrovalve (26) placed between the pump and the ramp (14, 20). The pump (12) is fitted to supply under high-pressure 45-110 bars. The filter (16 or 50, 52) retaining the particles having a dimension higher than 1 mu or a charged filter retaining the particles and colloidal substances having a dimension higher than 0.5 mu . The ultrafiltration filter (18) to retain the microorganisms having a dimension higher than 0.2 mu . The microorganisms of chamber having dimension is lower than 0.2 mu . The electrovalve placed in two positions, in which normal operation of the device and the circulation of the liquid supplied under pressure by the circuit pump, which is closed within the interiors to carry out the decontamination of the device by thermal shock. A reservoir with a float device (40) to maintain the maximum level of water, in which there is a heat resistant element to achieve a decontamination by thermal shock of the device at 70[deg]C for 10 minutes, when the pump was operated to circulation of water under a pressure of 5 bars. A proportioning pump supplying biocide or virucide products to prevent the formation of a biofilm in the pipes between the pump and the ramp and retaining the particles of size higher than 5 mu . Draining outlets for the ramp and pump. The pipes (11, 24, 28, 30) are connecting the copper element.

Description

The present invention relates to water misting devices

  intended primarily for all establishments requiring bacteriologically perfect hygiene, such as hospitals,

  retirement homes and industrial installations requiring misting devices, and particularly concerns a misting device with maximum decontamination.

  The fogging of a liquid, and in particular the misting using water, is a cooling technique increasingly used in public places to fight against heat stroke especially during periods of heat wave. It consists in projecting with water mist nozzles water droplets having a size ranging from 3 g to g by means of a high pressure pump between 45 and 110 bar.

  It is a relatively economical process, flexible of use, effective and well accepted by the users.

  Unfortunately, very little care is taken in existing systems to ensure that the sprayed water does not contain pathogenic microorganisms. However, the technique of misting, because of its intrinsic characteristics, has the ability to promote the proliferation of microorganisms.

  This is especially true for the risks of contamination with legionella bacteria. However, the number of cases of Legionnaires' disease reported is constantly increasing, and the majority of these cases concern more specifically vulnerable people such as the elderly with chronic diseases, but also, more recently, the youngest. This contamination is mainly due to a class of Legionella, Legionella pneumophila.

  The contamination process also involves other bacteria or viruses that cause diseases such as SARS or bird flu. These diseases can be transmitted by all aerolization processes such as misting which generate droplets whose inhalation by the respiratory tract generates very serious lethal pulmonary lesions.

  Therefore, the object of the invention is to provide a misting device in which the liquid droplets provided by the misting nozzles do not contain pathogenic microorganisms.

  The object of the invention is therefore a misting device comprising a misting ramp comprising a plurality of misting nozzles, a liquid source supplying the liquid for supplying the misting ramp, a pump adapted to supply the liquid under pressure. from the source to the misting ramp. The misting device further comprises at least one particle filter retaining particles having a size greater than about 1 receiving the liquid from the source and an ultrafiltration filter receiving the liquid from the particulate filter to retain microorganisms having a size greater than 0.2p, and an ultraviolet beam receiving the liquid from the ultrafiltration filter and adapted to destroy residual microorganisms with a size less than 0.2p.

  The objects, objects and features of the invention will appear more clearly on reading the following description with reference to the drawings, in which: FIG. 1 is a block diagram showing a first embodiment of the misting device according to FIG. and Figure 2 is a block diagram showing a second embodiment of the misting device according to the invention.

  Although the device according to the invention shown in the figures can use any liquid, the preferred embodiments described below use water.

  The first embodiment of the misting device illustrated in Figure 1 is mainly used in hospitals and nursing homes. It comprises, like any misting device of this type, a water source 10 which is generally the water distribution network, a pump 12 adapted to supply water at high pressure output of between 45 and 110 bar, and a misting ramp 14 having misting nozzles (not shown). Although this is not the subject of the invention, it is recalled that the misting is to bring into the air fine water droplets that are very quickly evaporated. This causes changes in the physical characteristics of the ambient air which result in an increase in hygrometry and adiabatic cooling (that is to say without heat exchange with the outside) by evaporation of the water causing a lowering of the temperature of the atmosphere. The nozzles consist of a pressurizing chamber in which is located a finned stainless cylinder. The water projected against this cylinder acts as a lubricant by rotating and disintegrating it into microscopic particles smaller than: 10u which are driven externally by the high pressure. A flow of air is created to the extent that the hygrometric degree of air in the whole room tends to become uniform. This gives a natural ventilation of the room. Note that it is also possible to install a fan if you want to get faster ventilation.

  As already mentioned, the misting device according to the invention essentially comprises a particulate filter 16 receiving water from the source 10, an ultrafiltration filter 18 and a UV ultraviolet beam 20 in this order.

  Note that the inlet pipe 11 from the source 10 leads to a first three-way solenoid valve 22. In normal operation, the solenoid valve is in its first position passing the water from the source 10 to the particulate filter 16. In its second position, the water from the source 10 is diverted by the pipe 24 to a second three-way solenoid valve 26 interposed between the outlet pipe 28 of the pump and the pipe 30 serving to supply the fogging ramp 14. In normal operation, the solenoid valve 26 is in its first position, that is to say that for connecting the pipe 28 to the pipe 30 for supplying the ramp 14. The two solenoid valves are put in their second position to perform a total decontamination of the device as will be seen later.

  The particulate filter 16 may be a particulate filter retaining particles having a size greater than about 1 or a charged particle filter retaining particles and colloidal substances having a size greater than about 0.5 receiving the liquid from the source, which is sufficient to cancel any turbidity of the water.

  The ultrafiltration filter 18 placed after the particulate filter 16 retains a large part of the microorganisms, that is to say all those whose size is greater than 0.2 p, and retains in particular the bacteria present in the water .

  But the ultrafiltration filter is not enough. This is why it is necessary to add downstream a UVC (Ultra Violet Type C) chamber to destroy all the microorganisms whose size is less than 0.2p and mainly viruses that are too small to be retained by the filter. ultrafiltration.

  Note that the presence of the particulate filter and ultrafiltration filter upstream of the UVC ramp is absolutely necessary to achieve maximum decontamination which is the purpose of the invention. Indeed, the UV ramp can only work properly if the water is not cloudy. Hence the need to place the particle filter upstream which eliminates the turbidity of the water. But the ultrafiltration filter is just as necessary because it blocks large microorganisms that otherwise could screen for microorganisms of infinitesimal size such as viruses. Therefore the decontamination would not be perfect without this presence of the two filters upstream.

  The UVC boom consists of one or more low-pressure mercury vapor lamps emitting at the germicidal wavelength of 253.7 to 258 nanometers. These lamps are placed in quartz sheaths. The water circulates in the treatment chamber 20 around the quartz sheaths. These sheaths serve as separation between the lamp (s) and the liquid as electrical and thermal insulation and allow operation at an optimum temperature.

  A UV meter 32 indicates permanently in percentage with respect to the intensity of the lamp emitted at the beginning of life, the intensity received at the most unfavorable point of the chamber. It is an indicator of efficiency that takes into account all the parameters influencing performance such as lamp aging, clogging of quartz sheaths covering lamps and degradation of water quality. The UV meter can control an alarm device (not shown) that triggers when the intensity emitted by the lamps is insufficient to ensure perfect decontamination of the water.

  An automatic cleaning device 34 may be connected to the UVC ramp chamber 20. This device acts by scraping to remove deposits that may have formed on the quartz sheaths and thus mask the radiation. This device thus avoids the disassembly of the lamps and the emptying of the chamber. It can be triggered according to two modes of operation: either by the intensity decrease of the UVC radiation measured by the UV meter 32, or by programming a regular cycle which depends on the operating time of the UVC lamps.

  An important feature of the first embodiment illustrated in FIG. 1 is the presence of a reservoir 36, whose capacity is greater than 1 liter, located downstream of the ultrafiltration filter 18. It is thus placed so that the maximum of microorganisms it is removed from the water it contains by the ultrafiltration filter placed upstream, in order to prevent the growth of germs in the tank that can lead to contamination.

  This tank allows, if necessary, a total decontamination of the misting device through the technique of thermal shock. Indeed, raising the temperature of the liquid to 70 C guarantees the elimination of any microorganism. As soon as the misting device no longer works, for example at the end of the day, or if it has not been used for a certain time, the thermal shock process is started. To do this, the tank 36 comprises a heating resistor element 38 which raises the temperature in the tank to 70 C. The two solenoid valves 22 and 26 are then put in their second position at the same time as the pump is put into operation during a period of about 10 minutes to provide the water output at a pressure of 5 bar. During this period, the water flows in a closed circuit inside the misting device since the electrovalve 26 in the second position sends the water received from the pump to the solenoid valve 22 which, also placed in second position, sends the It should be noted that the seals used in the misting device are suitable for undergoing a temperature of 70.degree. C.

  In order to obtain the best decontamination possible, the tank comprises a float device 40 to maintain the maximum level of water tank still below the water inlet in the latter.

  Before being put back into operation, the misting device is drained so as to eliminate any risk of contamination. To do this, there are three emptying outlets located at the bottom: the discharge outlet 42 for the misting ramp, the drain outlet 44 for the pump and the drain outlet 46 for the tank.

  As already mentioned, the misting device that has just been described is particularly suitable for hospitals and retirement homes, mainly in the rooms of patients at high risk, impotent, bedridden or dependent, unable to access a common room refreshed, but also in common ward (replacing the air conditioning generating nosocomial infections Legionella Pneumophila) to refresh this place by lowering the ambient temperature by several degrees generating thermal comfort, in the common rooms incorporating the installation of misting and ceiling ventilation and outdoor ventilation for all recreational or recreational activities of residents generating comfort and a feeling of refreshment pleasant to the participants.

  The second embodiment illustrated in FIG. 2 is mainly used in industrial installations requiring permanent misting, such as paper mills or waste dumps, but also in poultry plants or greenhouses. In this embodiment where the length of the pipes downstream can reach lengths of several hundred meters, the decontamination of the device is not effected by thermal shock but by another means explained later. The presence of the tank is no longer necessary or that of solenoid valves for cleaning in a closed circuit.

  As before, the water is supplied by a source 10 which is generally the water distribution network. A pump 12 is adapted to supply the high-pressure outlet water between 45 and 110 bars to a misting ramp 14 comprising misting nozzles whose operation has been described in the first embodiment.

  The water inlet pipe 11 from the source 10 brings the water to a series of three filters, two particulate filters 50 and 52 and an ultrafiltration filter 18 followed by a UV 20 ultraviolet beam as previously . The first filter 50 is a positively charged filter stopping all particles larger than 4.5 p. Second filter 52 stops all particles and colloidal materials larger than 0.5 p. As mentioned before, the UV ramp can only work properly if the water is not cloudy. It is therefore necessary to reduce the turbidity of the water as well as the suspended solids (MES). Hence the need to place particle filters upstream. The ultrafiltration filter 18 is just as necessary since it makes it possible to block large microorganisms which, without this, could screen for microorganisms of infinitesimal size such as viruses which are eliminated by the UV ramp.

  Note that in applications using the second embodiment, the particulate filter 50 which protects the two following filters, is inexpensive and is changed frequently, for example once a month. The second filter 52 is changed only every six months, and the ultrafiltration filter 18, which is more expensive, can only be changed once a year.

  As for the first embodiment, the UV ramp 20 consists of mercury vapor lamps placed in quartz sheaths. An UV meter 32 permanently indicates, in percentage with respect to the intensity of the lamp emitted at the beginning of life, the intensity received at the most unfavorable point of the chamber. As before, an automatic cleaning device can be connected to the UV ramp chamber 20.

  In industrial applications where the second embodiment can be implemented, the misting ramps can have total lengths of 400 m. It is therefore absolutely necessary to secure the entire device to be able to prevent the formation of a biofilm of microorganisms such as legionella in the pipes leading to the misting ramp by regular treatment by means of a metering pump 53 allowing inject regularly products fighting against the formation of this biofilm. Such products are biocidal compounds destroying bacteria or better, virucidal compounds destroying viruses as well as bacteria. In this way, the quality flowing in the device will be equal to that obtained at the output of the UV ramp.

  Since the products supplied by the metering pump 53 can cause rapid shut-off of misting nozzles, it is advisable to add an antiparticle filter 54 to stop particles larger than 5u at the output of the metering pump 53.

  Regularly, the misting device is drained so as to eliminate the slightest risk of contamination. To do this, there are two emptying outlets located at the bottom: the discharge outlet 42 for the misting ramp and the emptying outlet 44 for the pump.

  Note that all the pipes connecting the elements of the misting device such as the pipe 11 from the source 10 or the pipe 28 connecting the pump 12 to the misting ramp 14 are preferably copper which is a bactericidal metal or alloy of copper.

  The misting device according to the invention can also be used in public places such as motorway areas, railway stations, airport lobbies, or private places such as patios, restaurant terraces, shops, etc. It can also be used in professional sites such as greenhouses, fish stalls, vegetable stalls or humid Aero-refrigerant towers (TAR).

Claims (15)

  A misting device comprising a misting ramp (14) comprising a plurality of misting nozzles, a liquid source (10) supplying the liquid for supplying said misting ramp, a pump (12) adapted to supply under high pressure. , generally between 45 and 110 bar, the liquid coming from said source at said misting ramp; said device being characterized in that it further comprises: at least one particulate filter (16 or 50, 52) retaining particles having a size greater than about 1 g receiving the liquid from said source, and an ultrafiltration filter (18) receiving the liquid from said particulate filter to retain microorganisms having a size greater than 0.2i, and a UVC ramp chamber (20) having one or more UVC lamps placed in quartz sheaths receiving the liquid from said ultrafiltration filter and adapted to destroy microorganisms with a size smaller than 0.2t.   2. Device according to claim 1, wherein a UV meter (32) is associated with said UV ramp chamber (20), said UV meter continuously indicating the dose received at the worst point of the chamber in percentage relative to the intensity of the lamps emitted at the beginning of life.   3. Device according to claim 2, wherein an automatic cleaning device (34) is associated with said UV ramp chamber (20), said automatic cleaning device acting by scraping to remove deposits that may have formed on the sheaths. of quartz surrounding the lamps.   The device according to claim 3, wherein said particulate filter (16) is a filter retaining particles having a size greater than about 1 or a charged particulate filter retaining particles and colloidal substances having a size greater than about 0 , 5.   The apparatus of claim 4, further comprising a first three-way solenoid valve (22) positioned between said source (10) and said particulate filter (16) and a second three-way solenoid valve (26) positioned between said pump (12) and said misting ramp (14), said solenoid valves being able to be put in two positions, a first position allowing the normal operation of said misting device and a second position allowing circulation of the liquid supplied under pressure by the closed circuit pump inside said device so as to perform the decontamination of said device by thermal shock.   6. Device according to claim 5, further comprising a reservoir (36) in which there is a heating resistance element (38) for heating the water of the reservoir at a temperature of 70 C for a period of 10 minutes so as to performing a thermal shock decontamination of the misting device when said solenoid valves have been placed in their second position and said pump (12) has been put into operation to circulate the water under a pressure of 5 bar.   7. Device according to claim 6, wherein said reservoir (36) comprises a float device (40) for maintaining the maximum level of water in said tank always below the water inlet in the latter (disconnection network).   8. Use of the device according to one of claims 4 to 7 in hospitals and retirement homes.   9. Device according to claim 3, comprising a first particulate filter (50) retaining particles larger than 1 p followed by a second particulate filter (52) retaining particles or colloidal substances a size greater than 0.5 p. The device of claim 9, further comprising a metering pump (53) following said UVC ramp chamber (20), said metering pump providing biocidal or virucidal products on a regular basis for the purpose of preventing the formation of a biofilm in the pipes between said pump (12) and said misting ramp (14).   The device of claim 10, further comprising a particulate filter (54) positioned subsequent to said metering pump holding particles larger than 5 percent. 12. Device according to claim 6, 7, 10 or 11, further comprising emptying outlets located at the bottom, and in particular a drain outlet (42) for said misting ramp (14) and a drain outlet ( 44) for said pump (12).   13. Device according to one of claims 1 to 12, wherein all the pipes (11, 24, 28, 30) connecting the elements of the misting device are copper.   14. Device according to one of claims 1 to 13, wherein said source of liquid (10) is a source of water.   15. Use of the device according to claim 9, 10 or 11, in industrial or poultry installations requiring a misting device, and in particular in paper mills.