This application claims the benefit of priority of Italian Patent Application No. 102018000005614 filed on May 23, 2018, the contents of which are incorporated herein by reference in their entirety.
The present invention relates to a method, and an appliance for implementing the method, for washing parts and components for pharmaceutical production.
In the field of pharmaceutical production, it is known that washing systems need to be used in order to remove product or contaminants from drug production parts and various components such as: bins, press punches, drug injection pumps, tubing and valve parts, etc. It is also known that washing procedures must be carried out in order to remove pharmaceutical product or contaminants from bins used for transforming and storing pharmaceutical products. Such procedures must be carried out both during normal single-product production and, in particular, when using the same systems/components in multi-product lines. In this latter case, the washing procedure must ensure, prior to producing the next product, the elimination of any product residues and contaminants from the parts subjected to the washing cycle and also from those parts of the washing machine which have come in contact with the liquid used during the various cycle steps.
The washing procedures known in the art are of two types:
The automatic washing machines available on the market typically operate in accordance with a procedure that, depending on the nature of the product to be removed from the parts to be washed, includes the following steps:
This type of procedure is usually employed for part washing machines suitable for washing components and equipped with circuits for external and internal washing through a dedicated basket connected to the washing cycle by means of a “quick-lock” device, and also for large machines used for washing pharmaceutical bins, called bin washing machines.
Another method which is mostly used for washing bins makes use of a direct open circuit: in this case, the water taken in from the customer's loop is directly pressurized, without using an accumulation basin, and sprayed onto the load to be washed, possibly with in-line detergent injection and in-line heating. After hitting the load, the water falls and is directly conveyed into the drain pit.
It is often required that the parts, after having been washed and before returning to the production departments, be decontaminated at high temperatures (approx. 120-130° C.); this process usually occurs in other dedicated machines called autoclaves.
Both types of automatic washing processes (recirculation and open circuit) have some advantages and disadvantages.
Recirculation washing: this system offers more flexibility and allows for more appropriate washing rates and pressures. Moreover, it allows washing many components together, since many washing nozzles/systems can be simultaneously present aboard the machine. Since chemicals (detergents) need to be used in order to remove/decontaminate the components, it is necessary to use hot water (when injected into cold water, detergents produce foam, resulting in pump cavitation and reduced mechanical washing performance), and therefore energy.
Recirculation inevitably results in pockets of residue accumulation between one step and another: notwithstanding the self-draining design of the machines and the use of specific components, it is currently impossible to ensure the complete absence of even minimal accumulation areas. According to design rules, in fact, some minimum accumulation values are considered acceptable. It is therefore mandatory to carry out costly repetitions of the rinsing steps with water that is increasingly bacteriologically pure, which is however contaminated with previous residues.
For this reason, the final rinsing must often be carried out with ultra-pure water; however, this step poses a number of problems.
First of all, the presence of this type of water in the customer's systems, considering the complexity and production cost thereof.
Secondly, where this ultra-pure water is available it is still necessary to take into account that, in order to directly supply washing circuits designed for high flow rates, a line providing significant flow rates must be available. This is very difficult to obtain, because these are ultra-filtered lines with very high production costs.
Thirdly, even when flow rates are sufficient to ensure load coverage, there is still a problem as regards the proper rinsing of the machine (with its accumulation tank and associated piping).
Therefore, in order to avoid any contamination between one cycle and the next, an unloaded self-cleaning cycle is sometimes carried out, which inevitably results in downtime and water and energy consumption.
As an alternative, clean steam (when available) is injected into the machine, which results in problems related to consumption and, most importantly, safety, since a sealed chamber, not just a piping, needs to be treated.
Open circuit washing: this is a less flexible solution, because of its limited flow rates and coverage: this type of washing is mostly used for washing specific components (bins), where a single washing point is used along with low flow rates.
This solution requires that good lines are available, with appropriate water flow rates for feeding the circuits.
Basically, the washing/rinsing steps do not last very long, due to the significant instantaneous consumption of water.
In this case, contamination between two different steps can be avoided as concerns the load to be washed. If a wash chamber is present, however, the latter is not (unlike recirculation washing) fully hit by the washing/rinsing jets, and therefore the chamber itself becomes a receptacle of contaminants, since it has no effective self-cleaning system. Unloaded self-cleaning cycles may be carried out, which are however resource, power and time intensive, and anyway coverage is still poor because the circuits are dedicated to covering the components, not the chamber.
It is an object of the present invention to provide a washing appliance adapted for application in pharmaceutical production and/or preclinical pharmaceutical research centres, for washing parts and components for pharmaceutical production, and a method of use of the appliance.
The present invention relates to a washing appliance adapted for application in pharmaceutical production and/or preclinical pharmaceutical research centres, and adapted for the execution of washing/rinsing steps on parts and components for pharmaceutical production, comprising a hydraulic circuit for the circulation of washing/rinsing liquid and a recirculation pump in the hydraulic circuit, characterized in that it comprises:
The present invention also relates to a method of use of said washing appliance, characterized in that said washing/rinsing steps of the appliance are controlled by said control system in order to carry out said mixing of gaseous ozone in said washing/rinsing liquid during one or more of the following washing/rinsing steps:
It is a particular object of the present invention to provide a washing appliance adapted for application in pharmaceutical production and/or preclinical pharmaceutical research centres, for washing parts and components for pharmaceutical production, and a method of use of the appliance, as set out in the claims, which are an integral part of the present description.
Further objects and advantages of the present invention will become apparent from the following detailed description of a preferred embodiment (and variants) thereof referring to the annexed drawings, which are only supplied by way of non-limiting example, wherein:
In the drawings, the same reference numerals and letters identify the same items or components.
The present invention relates to a washing appliance adapted for application in pharmaceutical production and/or preclinical pharmaceutical research centres, which can process components and bins and allows the use of the recirculation technique, while eliminating the problem of residual contaminants by adding to the process a decontamination step using ozone.
This is achieved through the application of a generator aboard the machine to produce gaseous ozone to be mixed with the recirculated water.
The technology for producing ozone and mixing it with water is per se known.
The sanitizing properties of ozone are also known and can be summarized as follows:
It must also be pointed out that ozone production occurs simply through the use of a small quantity of filtered and dried compressed air (already available in the machine) and very little electric energy.
The following will describe the appliance as a whole and the specific application of ozone with reference to the annexed drawings.
The appliance comprises a wash chamber 1 internally comprising an accumulation basin (tank) 2 at the bottom, underneath the base level. Inside the wash chamber 1, bins and carriages dedicated to the washing of components can be loaded through sealed door(s) 20 accessible on the side(s) of the machine (
In the wash chamber 1 there are one or more of the following washing systems, provided with suitable holes or nozzles for delivering the washing liquid, which systems are connected to the hydraulic circuit of the appliance for circulating and recirculating the washing/rinsing liquid:
In one embodiment, the upper washing head 4, connected to a suitable liquid supply system 41, can move vertically within the wash chamber for the purpose of covering the entire load to be washed.
Preferably, in the chamber 1 there are a liquid level meter and a temperature probe (not shown in the drawings) co-operating with the electronic control system 18, which will be described below.
The accumulation basin 2 is directly connected to a sanitary recirculation pump 8 capable of pressurizing the supplied water and feeding, whether alternately or simultaneously, one or more of the above-mentioned washing systems through the hydraulic recirculation circuit.
The hydraulic circuit includes an in-line heat exchanger 10 for heating and maintaining the temperature of the washing/rinsing liquid received from the recirculation pump 8, a pressure switch and a temperature probe (not shown in the drawings). In the exchanger, heating is attained in any known manner.
The outlet of the heat exchanger 10 supplies the washing/rinsing liquid to the above-described washing systems of the chamber 1.
Through a drain valve 11 located at the lowest point of the hydraulic circuit, and connected to the accumulation basin 2, it is possible, by issuing an appropriate command, to completely drain the liquid circulating in the system.
On the top wall of the chamber there is an air extraction system 12 for extracting the air from inside the chamber by means of a fan intercepted by valves 13. This system ensures that the vapours generated during the process are extracted prior to opening the door(s) of the wash chamber.
There is at least one water supply point 7 for the hydraulic circuit, preferably connected to the delivery side of the recirculation pump 8.
Parallel to the heat exchanger 10, a bypass-line 12 of the hydraulic circuit is provided, which is equipped with a contact system connected to a gaseous ozone generation system. The contact system includes mixing means, which in one embodiment consist of a known Venturi-effect mixer 14 appropriately sized to ensure proper mixing in water of the gaseous-phase ozone produced by the generator. Advantageously, the mixing system 14 is arranged along the exchanger by-pass line, but it may also be located elsewhere in the hydraulic circuit, provided that it allows mixing the ozone in the recirculated liquid. The ozone generation system comprises a known gaseous-phase ozone generator 15, with a line for carrying the gaseous ozone towards the mixer 14. There is also an electronic control system 18 (e.g. a PLC) for controlling the ozone generator, and an ozone concentration meter 16 along the by-pass line 12, which provides the electronic control system 18 with a measurement of the ozone concentration in the liquid.
The electronic control system 18 also controls the recirculation pump 8 during the different steps of the washing cycle, changing the speed and pressure thereof accordingly, and the valves comprised in the hydraulic circuit for feeding the various spraying systems. During any step and at any instant of the washing/rinsing cycle, it is possible, after having filled the water accumulation basin 2, to mix gaseous ozone with the water in the hydraulic system, according to the following sequence:
The above-described operations are controlled through the electronic control system 18, the implementation of which is not a problem for a person skilled in the art on the basis of the information provided herein about the types of control to be carried out.
As aforesaid, the pressure of the washing liquid is adjustable according to the chosen cycle and the parts to be washed. In one exemplary embodiment, the adjustment range is 1 to 7 bar, since the bath recirculation pump is supplied by means of an inverter.
Ozone concentration in water may have values in the range of 1-2 ppm.
As far as cycle times are concerned, variability is high and may range from a few minutes to a few hours.
As far as the operation of the appliance is concerned, the above-described machine can be used for many applications:
The above-described solutions fulfil the need for solving the problems of the accumulation of contaminants and/or detergents in classic recirculation-type washing systems, in addition to offering the possibility to carry out cycles without using detergents and high temperatures.
The above-described non-limiting example of embodiment may be subject to variations without departing from the protection scope of the present invention, including all equivalent designs known to a man skilled in the art.
A possible embodiment variation is described here below.
The control probe (16) of the ozone quantity can be placed at one point of the hydraulic circuit on the return of the washing liquid recirculation, for example upstream of the mixer 14 and of the heat exchanger 10, and downstream of the delivery of the recirculation pump 8 and of the outlet of the accumulation basin 2 (see
During the production and mixing of Ozone the control probe (16), suitably placed on the return of the recirculation, verifies the increase of the residual mixed ozone and indirectly determines a control of the bacterial abatement that is being obtained in the plant. Ozone is an extremely unstable molecule with a strong oxidizing power: this means that once produced it remains stable if and only if it does not find a bacterial charge or organic material to oxidize.
The increase in ozone concentration on the return of the recirculation (and therefore at the reading point of the probe 16) occurs only after the quantity of ozone produced and mixed with the washing liquid is greater than the part that is lost due to oxidation-reduction phenomena for combination with the bacterial load or organic material to be abated.
Proceeding with the production and mixing and since the plant is isolated from the outside, the bacterial load and any organic charge present decrease, due to oxidation-reduction with ozone, until the microbiological conditions of the plant improve and the concentration of residual ozone on the return begins to rise. This means that if the mixed ozone value is read only downstream of the injection point 14 (see
Once this value is reached, it is possible to set a maintenance phase according to the needs and continue with the necessary combinations, keeping the ozone level monitored and modulated.
As mentioned above, the control system is therefore also able to provide an indication of the level of bacterial or contaminant charge present in the washing chamber, based on the measurement of the time required to reach the desired ozone concentration level in the washing liquid, starting from the beginning of delivery.
Therefore it is particularly advantageous to use the washing apparatus object of the invention in the context of the variant described above, being able to better control the ozone delivery time and the amount of ozone injected, increasing the effectiveness of the washing method, in any of the washing/rinsing phases described above. The elements and features shown in the various preferred embodiments may be combined together without however departing from the protection scope of the present invention.
From the above description, those skilled in the art will be able to produce the object of the invention without introducing any further construction details.
All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. To the extent that section headings are used, they should not be construed as necessarily limiting. In addition, any priority document(s) of this application is/are hereby incorporated herein by reference in its/their entirety.
Number | Date | Country | Kind |
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102018000005614 | May 2018 | IT | national |