The invention relates to a device for rinsing products, such as biological products, with a rinsing fluid. The invention further relates to a filter device for filtering a fluid for particles. The invention also relates to a method for rinsing products with a rinsing fluid.

It is known to rinse products. High standards are herein set for the rinsing fluid, which is preferably water. The object of the invention is to provide a device and a method wherein rinsing fluid is used and reused in efficient manner, wherein high standards of hygiene are met .

This object is achieved according to the invention in that the device according to the invention comprises a rinsing device for rinsing products, comprising a frame on which is arranged a supply means for products . This supply means is for instance a conveyor belt. The supply means at least supplies the products to a rinsing space in which is arranged a distributing means, such as a spray means, for distributing the rinsing fluid onto the supplied products. A collecting means is herein also arranged for collecting the rinsing fluid. The device according to the invention further comprises a filter device for filtering grains out of the rinsing fluid, comprising a second frame provided with a container with a feed for collected rinsing fluid, wherein the container comprises at least a ceramic filter for cleaning the rinsing fluid and ultrasonic cleaning means for cleaning the ceramic filter. The ceramic filter is per se known, as is cleaning of the filter with ultrasonic sources.

Ceramic filters are very suitable for filtering a rinsing fluid according to particle size. The ceramic membrane herein becomes contaminated and the ultrasonic means can destroy the contaminants. According to the invention the container further has a first outlet for rinsing fluid, which lies downstream of the filter.

The device further comprises a cleaning device for bacteriological cleaning, comprising a chamber for rinsing fluid and electrolytic means for electrolytic treatment of rinsing fluid situated in the chamber. The electrolytic means are adapted to activate chlorine present in the rinsing fluid. A small quantity of chlorine is often present in a rinsing fluid such as water. Through specific current and voltage selection, as well as a specific choice of electrodes, the process can be adapted for cleaning of the fluid by the electrolytic reaction in which chlorine gas is released. The rinsing fluid present in the chamber is hereby also cleaned of bacteria such as legionella. According to the invention a first conduit is arranged for rinsing fluid which preferably connects the first filter device to the chamber via the outlet. A second conduit is preferably also available for connecting the chamber to the rinsing space. A device is hereby obtained wherein the rinsing fluid is at least partly reused. The device can operate continuously to a certain degree, and the necessary cleaning and filtering are achieved in efficient manner. In another embodiment a first conduit can connect the collecting means to the cleaning device, and a second conduit can connect the cleaning device to the filter device, wherein the outlet of the filter device is connected to the rinsing device. The device according to the invention provides an at least partially recycling circuit for rinsing fluid.

The cleaning device preferably comprises feed means for feeding a chlorine-containing substance to the chamber for bacteriological cleaning of the rinsing fluid. The dissolved chlorine is activated and removed by specific electrolysis. The rinsing fluid in the device according to the invention does not become chemically contaminated as a result . The treatment of the rinsing fluid can hereby be repeated a number of times. Environmental pollution is hereby prevented. The resulting or added quantity of chlorine becomes very limited and remains within the current European guidelines in respect of chlorine concentrations.

The device preferably has a second outlet for rinsing fluid lying upstream of the filter. This second outlet lies in front of the filter and can also be used for the discharge of contaminated rinsing fluid. This second outlet can particularly be used at the moment that the ultrasonic cleaning means for the ceramic filter are set into operation. The filters are hereby cleaned and dirt, in particular grains such as sand, will be released which can be discharged via the second outlet .

The container preferably has at least three compartments, wherein the feed for collected rinsing fluid is connected to at least two compartments for feeding rinsing fluid to these compartments, which compartments are situated on the upstream side of the filter and wherein the first outlet is connected to a compartment on the downstream side of the filter. Each filter is provided with ultrasonic cleaning. When the filter is cleaned in a first compartment, rinsing fluid can be supplied to the second compartment or vice versa. A continuous circuit can hereby be obtained for the cleaning and filtering of rinsing fluid. During cleaning

rinsing fluid can be discharged particularly from the first or second compartment via the second outlet.

In a particular embodiment the ceramic filter forms in each case a separation between two compartments. This is a particularly efficient manner of constructing the filter device, and therefore the whole device according to the invention.

According to a further embodiment, the first and second outlet are provided with first and second valve means respectively, and at least one compartment in the container has both a first and a second outlet, wherein a control device is adapted to open the second valve means during use of the ultrasonic cleaning means of this compartment. Dislodged dirt is hereby discharged via the opened second outlet. The first outlet is closed. The first outlet is likewise closed when rinsing fluid is supplied to this compartment. The first outlet is opened when this compartment is situated downstream of a ceramic filter, wherein the upstream filter of this ceramic filter is used for the feed of the rinsing fluid. Compartments having multiple functions are hereby obtained, and in this way the device can be applied in more efficient manner.

The filter device is preferably provided with fluid supply means for different compartments. The supply of a rinsing fluid to a compartment can hereby be closed at the moment the filter of the compartment is being cleaned. Rinsing fluid can then be guided to a different compartment, where it is filtered. The device according to the invention is for instance used for the treatment of flower bulbs. These are washed by rinsing with water. The water must herein also be treated against bacteria, in particular legionella. Sand is released during rinsing of the flower bulbs. This is collected in the filter device.

The ultrasonic cleaning means of ceramic filters can destroy the sand grains. The ceramic filters are porous membranes with cavities, which stop the sand grains. The ceramic filters are for instance adapted to filter all grain sizes larger than 10 microns. The ultrasonic cleaning means will destroy the grains larger than 10 microns. During the ultrasonic treatment the rinsing fluid present in the ceramic filter or the compartment can be discharged via a second outlet, a drain for rinsing fluid and grains.

The ultrasonic cleaning means vibrate for instance at a frequency of 18 to 40 kHz, preferably 18 to 25 kHz. The cleaning of the filter by ultrasonic means takes place in that the vibrations cause bubbles which are formed and then implode in the rinsing fluid. The formation and disappearance results in a vibration in the rinsing fluid which can destroy the grains.

The invention also relates to a filter device for filtering fluid for particles, comprising a frame provided with a container for fluid, which comprises a number of compartments separated by at least a ceramic filter, wherein a feed for a contaminated fluid is connected to at least two compartments located upstream of the ceramic filter, and a first outlet for filtered fluid which has a first valve means connected to the compartment on the downstream side of the filter. The compartments located upstream are herein also provided with a second outlet for fluid, and ultrasonic cleaning means for the ceramic filter are arranged in the container. A filter device is hereby obtained which can be utilized continuously. During cleaning of a filter it is possible to switch to one of the compartments not being cleaned at that moment. During cleaning of the filter with the ultrasonic source, dislodged grains can be discharged via the second outlet .

The filter device according to the invention can further be embodied according to the preferred embodiments of the filter device in accordance with the above description. The invention further relates to a method for rinsing products, wherein products are rinsed with a rinsing fluid, wherein the rinsing fluid is collected and filtered by means of a ceramic filter, wherein the filters are cleaned by ultrasonic sources, whereafter a cleaning agent such as chlorine is added to at least a part of the filtered rinsing fluid and wherein the cleaned and filtered rinsing fluid is fed back for renewed rinsing. A method is hereby obtained wherein a rinsing fluid can be reused. The efficiency of this method is exceptionally high. The costs can be kept very low because the filter can be cleaned continuously using the ultrasonic sources. The exceptional efficiency of such a system makes industrial application thereof very advantageous. The invention will be further described with reference to the annexed drawings, in which:

Figure 1 shows a schematic view of an embodiment of the device according to the invention;

Figure 2 shows a top view of a filter device according to the invention;

Figure 3 shows a side view of a filter device according to the invention; and

Figure 4 shows a front view of a filter device according to the invention; Figure 5 shows a schematic view of the filter device according to the invention.

Figure 1 shows the device according to a first embodiment. Device 1 comprises a rinsing device 2, a filter device 3 and a cleaning device 4. The devices in question are shown schematically. Rinsing fluid is

circulated through the devices in clockwise direction. The operation of the three devices and the mutual co- action will be described hereinbelow.

Rinsing device 2 comprises a conveyor belt 13 on which are placed products 4 such as flower bulbs. The conveyor belt moves as according to arrow 5 and the products are herein moved into rinsing chamber 6 of rinsing device 2. Conveyor belt 13 runs through rinsing chamber 6 and the products are herein guided under sprays 7 and 8.

Sprays 7 and 8 are connected to a pipe 9 which supplies rinsing fluid 10 which is sprayed over products 4 and conveyor belt 13. This can take place under pressure. Compressors and pumps for rinsing fluid are not shown.

In another embodiment, instead of rinsing with sprays, rinsing can take place by washing the products. They are then placed in a tank with rinsing fluid and moved in that rinsing fluid, for instance by shaking. The skilled person will be able to design other embodiments for a rinsing device for products in suitable manner.

In the shown embodiment rinsing fluid 10 is collected in a receptacle 11. In another embodiment the rinsing fluid with which the products are washed is discharged. The rinsing receptacle or washing receptacle is then itself the collecting means.

The collecting means are connected to a conduit 12 which can discharge the contaminated rinsing fluid. Sand is for instance rinsed off products 4 during rinsing or washing of the products. This is collected in collecting means 11 and discharged via conduit 12. Other contaminants, such as bacteriological ones, can also be taken up in the rinsing fluid during the rinsing.

Cleaned products 13 are further discharged via conveyor belt 13. The invention relates particularly to the cleaning of consumer goods or other biological products. Cleaning hereof requires particularly high standards.

Collected rinsing fluid is supplied to filter device 3 via conduit 12. Pumping is for instance carried out (not shown) . Rinsing fluid is carried via feed 14 into a container 15 consisting of two compartments 16,17. The compartments are separated by a schematically shown ceramic filter 18.

The contaminated rinsing fluid is supplied to a downstream side of filter 18. Grains such as sand in the rinsing fluid cannot pass through ceramic filter 18 and cannot reach compartment 17 and outlet 19. Filtered rinsing fluid is discharged via conduit 20.

In the first compartment 16 is also arranged a second outlet 21, in which a valve means 22 is accommodated schematically. Valve means 22 can open and close the second outlet.

A ceramic filter, which consists of a ceramic provided with cavities and which is porous to fluids, is particularly suitable for filtering according to grain size. The skilled person is familiar with suitable filters, for instance for filtering grain sizes larger than for instance 10 microns.

The arranging and fixing of a ceramic filter 18 in a container 15 is known to the skilled person.

A cleaning means 23 for the ceramic filter is shown schematically. Here this is an ultrasonic source which can generate vibrations 24 at a determined frequency. The ultrasonic source is arranged on the downstream side and is directed at the filter. The vibrations generated by ultrasonic source 23 in the rinsing fluid in compartment 16 and partly through

compartment 17 result in the destruction of particles, in particular sand. Particularly particles collected by ceramic filter 18 are destroyed. Filter 18 is hereby cleaned continuously and will not become blocked. The filter device is thus continuously usable. Maintenance is reduced considerably.

In a preferred embodiment valve 22 is opened during cleaning of filter 18. Contaminated rinsing fluid can hereby be discharged. The filtered rinsing fluid is supplied to cleaning device 4 via conduit 20. Other rinsing fluid can also be supplied to this conduit, as shown at 25. The rinsing fluid is fed into cleaning device 4 via feed 26 and is herein collected in a mixing chamber 27. The mixing chamber is shown schematically.

The rinsing fluid 28 situated in mixing chamber 27 can for instance be arranged in batches. The cleaning device for instance has a plurality of mixing chambers 27. Feed 26 and outlet 29 can be provided with valve means (not shown) for batch-wise treatment.

A chlorine-containing agent such as chlorine is preferably added to rinsing fluid 28 using a supply means 30. This is done by opening valve 31.

A chlorine composition can be added for the purpose of cleaning/destroying determined bacteria in rinsing fluid 28. This is used particularly to clean legionella out of the rinsing fluid. The chlorine- containing agent is added to mixing chamber 27, wherein the rinsing fluid is cleaned by the destruction of bacteria.

The bacteriological cleaning can be improved further by means of an electrolytic process which is shown schematically with electrode 32,33. The skilled person is familiar with electrolytic cleaning, in particular in conjunction with chlorine, whereby very

favourable results are achieved for the bacteriological cleaning of a fluid.

The filtered and cleaned fluid is discharged via 29 through conduit 9 and fed back to rinsing device 2. An at least partly closed circuit is hereby obtained, wherein rinsing fluid is reused after cleaning.

The cleaning and filtering according to the invention are particularly suitable for use in rinsing and washing biological products. Applicant's results with experiments have demonstrated that considerably improved results are obtained compared to the prior art, both in terms of efficiency and cost-saving. Surprisingly, an electrolytic circuit, wherein chlorine is generated and used to destroy bacteria, and filtering by means of a ceramic filter have mutually complementary properties, whereby an at least partly closed circuit for such a rinsing fluid is obtained at low cost, wherein maintenance costs are considerably lower.

As shown, the embodiment according to figure 1 is particularly schematic, and the skilled person will have knowledge which makes it possible to embody the device. In particular, the rinsing device, the filter device and the cleaning device can be embodied differently within the scope of the invention. The invention relates to the combination of the three stated parts, wherein the two particular cleaning techniques are applied.

Figure 2 shows a top view of a filter device according to a second embodiment. Filter device 50 comprises a frame provided with a feed 51. Rinsing fluid is supplied via the feed to container 52 which, as can be seen in figure 4, has a cylindrical cross-section. The container has a number of compartments 53,54,55,56,57.

Rinsing fluid can be supplied via feed 51 to one of the compartments 53,54,55,56,57. Rinsing fluid can optionally be supplied to two or more compartments. Conduits are arranged in the device from feed 51 to the respective compartments.

Compartment 53 is connected to second outlet 59 via a valve 58. Compartment 54 is connected to first outlet 61 via a valve 60, and to second outlet 59 via a valve 62. Compartments 55,56 are also connected to first outlet 61 and second outlet 59 via valve means.

Compartment 57 is connected to first outlet 61 via a valve means 63.

Valve means 58,60,62,63 are connected to a control device (not shown) . The control device can open and close the valves which are embodied in suitable manner, for instance as ball valve or other known valve type.

A ceramic filter is arranged in each case between the compartments. A ceramic filter 64 is placed between compartments 53 and 53. A ceramic filter 65 is placed between compartments 54 and 55. Ceramic filters 66 and 67 are further provided. In one embodiment the ceramic filters have the same properties in respect of filtering, in particular particle-size filtering. In another embodiment the filters can be embodied differently. In this latter embodiment different filtering properties can be obtained with one filter device 50.

When fluid is supplied to compartment 53 via feed 51, it can be filtered by ceramic filter 64 and enter compartment 54. Then situated here is filtered fluid which can be discharged to first outlet 61 via valve 60. Valve means 62 is then preferably closed.

Filtered fluid can be discharged via the first outlet. This takes place via an overflow principle,

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12 wherein fluid is for instance discharged via the first outlet by means of a pump, whereby the fluid level in the relevant compartment of the valve means will drop, whereby more fluid will be filtered. Not shown in the embodiment according to figures 2-4 are the ultrasonic cleaning means for ceramic filters 64-67. In one embodiment one ultrasonic source is arranged for the whole container. In another embodiment several ultrasonic sources are arranged, for instance one per ceramic filter. In yet another embodiment ultrasonic sources of different frequencies are arranged, or the frequency of the ultrasonic source can be regulated.

A particular property will occur in the ceramic filter through use of ultrasonic sources. The fluid will begin to produce bubbles locally, which then collapse. This has a cleaning action for the filter. The grains present in the filter and partially blocking the filter, such as sand, will be destroyed. The grain size will decrease considerably. Some of the grains will also be dislodged from the filter.

When one of the ceramic filters is cleaned, for instance ceramic filter 64, contaminated fluid can be discharged from compartment 53 via valve means 58 and outlet 59. The sand dislodged by the cleaning means of the ceramic filter will be able to disappear via this outlet.

According to the invention a filter device is obtained which can be utilized continuously. During cleaning of one of the ceramic filters this compartment cannot be used, but fluid can be supplied via feed 51 to a compartment which can however be used and a filter which is not being cleaned. This can be controlled by the control device (not shown) which regulates the feed to the diverse compartments, as well as the opening and

closing of valve means 58,60,62,63. When a ceramic filter is being cleaned, the valve means can be opened toward the second outlet of the upstream compartment of that filter. Embodiments according to figures 2-4 also require the control device to regulate the first valve means for first outlet 61 such that when fluid feed takes place to one of the compartments, the relevant valve of that compartment connected to first outlet 61 is in any case closed.

In an embodiment it is possible to feed fluid to compartment 56 and to then filter the fluid passing through ceramic filter 66 and ceramic filter 67. The filtered fluid can be discharged via outlet 61 via both valve means 63 and valve means 68.

The invention can be applied in diverse other ways. In appropriate manner the skilled person will be able to apply the invention in different ways in which at least an electrolytic cleaning and a filter cleaning takes place in a rinsing system by means of ceramic filters which can be cleaned by ultrasonic sources.

Figure 5 shows a feed 70 which is connected to compartments 75-78 via four conduits 71-74. A filter 79- 82 is arranged in each compartment. Fluid can be supplied to each compartment via feed 70. Feed depends for instance on the overflow in each compartment.

When one of valves 83-86 is opened, filtered fluid is discharged from the relevant compartment via outlet 87. Fluid will only reach the part of each relevant compartment 75-78 connected to one of valves 83-86 after having passed through filter 79-82, wherein a determined filtering is performed. The filters are preferably ceramic filters which filter according to particle size. The water discharged via outlet 87 is

thus free of grain sizes above a determined diameter. These grain sizes are stopped by ceramic filter 79-82.

The upstream compartment part of each of compartments 75-78 is connected to a drain 92 via one of the valves 88-91. When one of these valves is opened, unfiltered fluid is discharged. This is preferably applied when the filters are being cleaned, particularly during ultrasonic cleaning. The larger grains in the fluid can then be discharged via drain 92 via the opened valve. Part of the fluid is hereby discharged from the closed circle, but when one of the compartments is being cleaned the other three can be used, whereby a continuous operation of the system becomes possible. When valve 88 is opened, valve 83 is preferably closed. In another embodiment the feeds 71-74 can be provided with valve means. The respective valves 83-86 and 88-91 are preferably connected to a control device. When the ultrasonic cleaning means of ceramic filters 79-82 (not shown) are switched on, the relevant valves will close and open.

In another embodiment even more compartments can be used.