WO2023148749A1

WO2023148749A1 - Devices and methods for depyrogenation

Info

Publication number: WO2023148749A1
Application number: PCT/IN2022/050509
Authority: WO
Inventors: M. Nageswara RAO
Original assignee: Pharmalab India Pvt. Ltd.
Priority date: 2022-02-07
Filing date: 2022-06-01
Publication date: 2023-08-10

Abstract

The present disclosure relates to devices and methods for depyrogenating an article. The device (100) comprises a housing (102) to accommodate a receiving section (104) having a platform to receive the article, and an electrostatic precipitator (106) having an inlet, a filtration unit, and an outlet. The outlet is positioned adjacent to the receiving section (104). The filtration unit filters and collects particulate contaminants present in the circulated heated air. Further, the device (100) comprises a radiative heater (108), positioned above the platform, to heat ambient air in the receiving section (104). The device (100) also comprises a circulation unit (110) to circulate the heated air from the receiving section (104) towards the inlet of the electrostatic precipitator (106).

Description

DEVICES AND METHODS FOR DEPYROGENATION

TECHNICAL FIELD

[0001] The present subject matter relates, in general, to depyrogenation, and, particularly, to a depyrogenation device and a method for depyrogenating an article.

BACKGROUND

[0002] Depyrogenation techniques are employed for removing a pyrogen from a substance or an article, such as, a vial, a syringe, a container, a bottle, and so on, that are generally used in medical industry, pharmaceutical industry, food processing and packaging applications, etc.

BRIEF DESCRIPTION OF FIGURES

[0003] The detailed description is provided with reference to the accompanying figures, wherein:

[0004] FIG. 1 illustrates a schematic diagram of a depyrogenation device for depyrogenating an article, in accordance with an example implementation of the present subject matter;

[0005] FIG. 2 illustrates a sectional view of an electrostatic precipitator of a depyrogenation device, in accordance with an example implementation of the present subject matter;

[0006] FIG. 3A illustrates a pre-heating phase of a depyrogenation device, in accordance with an example implementation of the present subject matter;

[0007] FIG. 3B illustrates a heating and re-circulation phase of the depyrogenation device of FIG. 3 A, in accordance with an example implementation of the present subject matter;

[0008] FIG. 3C illustrates a cooling phase of the depyrogenation device of FIG. 3 A, in accordance with an example implementation of the present subject matter; [0009] FIG. 3D illustrates a cooling phase of the depyrogenation device of FIG. 3 A, in accordance with an example implementation of the present subject matter;

[0010] FIG. 3E illustrates an exhaust phase of the depyrogenation device of FIG. 3A, in accordance with an example implementation of the present subject matter; and

[0011] FIG. 4A to 4D illustrate methods for operating the depyrogenation device of FIG. 1, in accordance with an example implementation of the present subject matter.

[0012] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

DETAILED DESCRIPTION

[0013] Articles, having presence of pyrogenic substances, when used, may release endogenous factors triggering an immunological response within a human body. Typically, depyrogenation techniques are used for the inactivation and/or removal of such pyrogenic substances. In depyrogenation, dry heated air of high temperature is introduced around an article which is to be depyrogenated. Introduction of the dry heated air coagulates the protein structure as well the enzymes present in the microorganisms present on the article.

[0014] Depyrogenation is generally performed using depyrogenation tunnels or depyrogenation batch ovens. A depyrogenation tunnel includes a platform for placing one or more articles. Further, the depyrogenation tunnel includes multiple air blowers to direct an ambient air inside the depyrogenation tunnel, to circulate the air inside the depyrogenation tunnel, and to eject the exhaust air to an ambient environment. In addition, the depyrogenation tunnel may include filters, such as high-efficiency particulate absorbing (HEPA) filters and microporous filters. Each of the filters is selectively positioned to filter air at various stages, such as at an inlet, during recirculation, as well as prior to ejection of exhaust air to the ambient environment.

[0015] The use of multiple filters increases the overall cost of the depyrogenation tunnel. Further, the HEPA filters are required to be replaced at regular intervals as the HEPA filters may get clogged after a prolonged usage. Moreover, usage of multiple blower units increases an overall power consumption of the depyrogenation tunnel. Therefore, an overall cost involved in the usage of the depyrogenation tunnel for depyrogenation is increased.

[0016] Generally, a regulatory standard for validation of the depyrogenation process involves reduction of a pyrogen through 3 log 10 reduction. For achieving the inactivation of the pyrogen through 3 log 10 reduction, a depyrogenation batch oven may be required to operate at temperatures above 180°C. However, performing the depyrogenation at temperatures above 180°C requires more time for implementing the depyrogenation process. Therefore, the depyrogenation batch oven operates at a minimum of 250°C with peak temperatures approaching 350°C. Similarly, the depyrogenation tunnels are also operated at a minimum of 250°C with peak temperatures approaching 350°C.

[0017] Upon completion of the depyrogenation process at temperatures of upto 350°C, the articles are to be cooled before being used. Therefore, an overall time required to perform the depyrogenation process with existing depyrogenation batch ovens or depyrogenation tunnels is increased.

[0018] The present subject matter describes various approaches for depyrogenating an article. The approaches of the present subject matter implement a device for depyrogenating an article which uses a single blower and a single reusable filter for performing a depyrogenation process. The depyrogenation process performed by the exemplary device significantly reduces the power consumption, is efficient and convenient for depyrogenation of the articles, while increasing service life of the exemplary device. [0019] In an example implementation of the present subject matter, a device is proposed for depyrogenating an article. The device includes a housing. Further, the housing includes an electrostatic precipitator, a radiative heater, and a circulation unit. The electrostatic precipitator includes an inlet, a filtration unit, and an outlet. An article may be placed adjacent to the outlet of the electrostatic precipitator. The radiative heater may be positioned above the article. Alternatively, the radiative heater may be positioned adjacent to the article. Upon operation, the radiative heater is to heat the article and interior surfaces as well as air around and inside the article. Heating the air surrounding the article allows in the depyrogenation of particulate contaminants, including pyrogenic substances and microorganisms, present on the article. Upon heating the surfaces and air surrounding the article, the circulation unit is operated to circulate the heated air from the article towards the inlet of the electrostatic precipitator. The circulation results in heat convection inside the housing and carrying of the particulate contaminants in the air stream. Upon receiving the heated air, the filtration unit of the electrostatic precipitator filters by charging the particles and pyrogens and collects the particulate contaminants present in the circulated heated air. The circulation of the heated air is controlled by a set of valves present in the housing.

[0020] As per the present subject matter, upon completion of the depyrogenation, the radiative heater is switched off, and the air stream circulating inside the housing is introduced to a cooling unit of the device. The cooling unit is configured to lower the temperature of the heated air and introduce the cooled air within the housing through the electrostatic precipitator. The cooled air is then transferred to a surrounding area of the depyrogenated article for lowering the temperature of the depyrogenated article. During the process of depyrogenation and cooling, the circulating air is continuously filtered by the electrostatic precipitator. Further, upon completion of a cooling phase, the circulating air is expelled out from the housing. As the circulating air is continuously filtered during a depyrogenation phase, including heating and recirculation phases, and during the cooling phase, the exhaust air is free from any particulate contaminants. Therefore, the exhaust air does not affect purity of air in a surrounding environment. [0021] Upon completion of the process, the filtration unit, containing the filtered particulate contaminants, can be cleaned, thereby allowing for reusability of the filtration unit for processing further articles.

[0022] Accordingly, the approaches of the present subject matter provide a depyrogenation device including only a single blower and a single electrostatic filter for filtering the incoming air, the circulating air, as well as the exhaust air. Thereby, a requirement of multiple filters and blowers is eliminated. Further, regular replacement of the filters is not required as the electrostatic filter of the present subject matter having a smooth stainless-steel surfaces and more hygienic construction is easily cleanable and reusable with an indefinite life. Thus, an overall installation and operation cost of the filter is decreased. In addition, the depyrogenation device, as per the present subject matter, allows to preserve air quality by ejecting contaminant-free air in the outside atmosphere.

[0023] These and other advantages of the present subject matter would be described in a greater detail in conjunction with FIGS. 1 to 4D in the following description. The manner in which the devices of present subject matter are implemented shall be explained in detail with respect to FIGS. 1 to 4D. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope. Furthermore, all examples recited herein are intended only to aid the reader in understanding the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects and implementations of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.

[0024] FIG. 1 illustrates a schematic diagram of a depyrogenation device 100 (also referred to as a device 100) for depyrogenating an article (not shown in FIG. 1), in accordance with an example implementation of the present subject matter. The device 100 includes a housing 102 for accommodating a receiving section 104, an electrostatic precipitator 106, a radiative heater 108, and a circulation unit 110. The receiving section 104 includes a platform 112 on which the article for being depyrogenated is placed. In an example, the receiving section 104 may be operable in an open configuration and a closed configuration. In the open configuration, the article may be kept onto the platform 112 of the receiving section 104. Upon placement of the article, the receiving section 104 may be placed in the closed configuration. In the closed configuration, the housing 102 may form an airtight enclosed space containing the article.

[0025] The electrostatic precipitator 106 is positioned adjacent to the platform 112 to receive the article. The electrostatic precipitator 106 is provided to filter contaminants from a surrounding. The electrostatic precipitator 106 comprises an inlet (not shown in FIG. 1), a filtration unit (not shown in FIG. 1), and an outlet (not shown in FIG. 1). In an example, the filtration unit is present between the inlet and the outlet. Further, the electrostatic precipitator 106 is positioned in a manner such that the outlet of the electrostatic precipitator 106 is facing towards the platform 112. In the present example, the electrostatic precipitator 106 is configured to filter particulate contaminants having a cross-sectional dimension of 0.1 micrometers (pm) (100 nanometers (nm)). Detailed configuration and specification with respect to operation of the electrostatic precipitator 106 is described in the description of FIG. 2.

[0026] Further, in an example, the radiative heater 108 is positioned above the platform 112 to radiate heat on the platform 112. The radiative heater 108 may heat the ambient air and all interior surfaces in the receiving section 104. However, the radiative heater 108 may be positioned on any side of the platform 112 to radiate heat towards the platform 112 from respective sides. In another example, the device 100 includes more than one radiative heater that may be positioned at different places to radiate heat towards the platform 112 from multiple directions. In an example, the radiative heater 108 is an Infrared (IR) heater. Examples of the radiative heater 108 may include, but are not limited to, a twin tube infrared heater and a twin tube carbon fibre infrared lamp. In an example, the IR heater includes a gold reflector coating for increasing the overall heating capacity. For the present example implementation, the IR heater includes twin tube carbon fibre IR lamps having a cross sectional specification of 15 millimetres (mm) by 33 mm. Further, the total end-to-end length of the lamps is in a range of 550 mm to 650 mm. The IR heater is rated to work on 2000 Watts and 380 Volts. The device 100 includes the radiative heater 108 to raise an ambient temperature of the receiving section 104 of the housing 102 including the platform 112 to a predetermined temperature. In an example, the radiative heater 108 is capable to radiate heat of upto 650° Celsius (C). In the present example implementation, the radiative heater 108 is operated to raise the ambient temperature of the receiving section 104 of the housing 102 to range from 30° C to 600° C.

[0027] Further, the circulation unit 110 is positioned in the housing 102 such that, upon operation, the circulation unit 110 may receive heated air from the receiving section 104. In the present implementation, the circulation unit 110 is a blower fan. However, the circulation unit 110 may be any device 100 capable of transferring fluid from one place to other within the housing 102. The circulation unit 110 may circulate the heated air received from the receiving section 104 towards the inlet of the electrostatic precipitator 106.

[0028] Further, the device 100 comprises a valve 114 disposed on an inner wall of the housing 102. The valve 114 may be positioned such as to selectively allow flow of the circulated air towards the inlet of the electrostatic precipitator 106. For example, the valve 114 is operable between an open position and a closed position for selectively allowing recirculation of air from the circulation unit 110 towards the electrostatic precipitator 106. When the valve 114 is operated in the open position, the heated air received from the article, by the circulation unit 110, is directed towards the inlet of the electrostatic precipitator 106. Upon entering, the heated air passes through the filtration unit of the electrostatic precipitator 106. The filtration unit filters and collects particulate contaminants present in the circulated heated air. [0029] Further, the device 100 comprises a cooling unit 116, which is operably coupled with the circulation unit 110 and the electrostatic precipitator 106. In an example, the cooling unit 116 is a heat exchanger. In operation, the cooling unit 116 cools the heated air received from the circulation unit 110. Further, the cooling unit 116 provides the cooled air to the electrostatic precipitator 106 to decrease an ambient temperature of the receiving section 104 containing the article.

[0030] In the present example implementation, the cooling unit 116 is placed externally to the housing 102 of the device 100. However, the cooling unit 116 may also be designed to be arranged inside the housing 102. The cooling unit 116 comprises an inlet 118, a cooling passage 120, and an outlet 122. The inlet 118 is coupled with the housing 102 to receive the heated air from the circulation unit 110. For example, the housing 102 may include an opening port and the inlet 118 is coupled with the housing 102 via the opening port. Further, the inlet 118 includes an inlet valve 124 operable between an open position and a closed position. The inlet valve 124 may be configured in the closed position during a heating and recirculation phase of the device 100, in which the ambient air of the receiving section 104 is heated and the heated air is circulated in the housing 102. For example, the inlet valve 124 is configured in the closed position when cooling of the heated air is not required. The cooling passage 120 is fluidly connected to the inlet 118 at a first end. In the open position, the inlet valve 124 allows the heated air to enter into the cooling passage 120 through the inlet 118. It is to be noted that when the inlet valve 124 is in the open position, the valve 114 may be in the closed position to ensure that entire heated air is being directed towards the cooling unit 116 to avoid direct air entry to the electrostatic precipitator 106. The inlet valve 124 is configured in the open position to allow cooling of the heated air upon completion of heating and recirculation phase of the device 100.

[0031] Further, the cooling unit 116 comprises a primary inlet 126 to allow a cooling medium to enter the cooling passage 120. The cooling medium flows through the cooling passage 120. The cooling medium may be a coolant, such as water, or any other cooling fluid. The cooling medium is to lower a temperature of the heated air.

[0032] In an example, the cooling passage 120 includes a first channel and a second channel separate from the first channel. The first channel may be configured to receive heated air circulated from the circulation unit 110. The second channel may be configured to receive the cooling medium. In an example, the first channel is contiguous to the second channel. Upon receiving the heated air in the first channel and upon introduction of the cooling medium into the second channel, the cooling passage 120 causes heat exchange between the heated air and the cooling medium. The heat exchange causes reduction in the temperature of the heated air, and thus, resulting in the cooling of the heated air. Further, the outlet 122 provides a fluid connection between the cooling passage 120 and the housing 102. In an example, the outlet 122 includes an outlet valve 128 operable between an open position and a closed position to introduce the lowered temperature air into the electrostatic precipitator 106. The outlet valve 128 may be operable in the closed position in the heating and recirculation phase of the device 100, as well as in an exhaust phase upon completion of a cooling phase of the device 100.

[0033] Upon cooling of the heated air, the outlet valve 128 is opened to allow flow of the cooled air towards the inlet 118 of the electrostatic precipitator 106.

[0034] In addition, the cooling unit 116 comprises an exhaust outlet 130 projecting outwards from the outlet 122 and extending away from the housing 102. The exhaust outlet 130 comprises an exhaust valve 132 operable between an open position and a closed position to eject exhaust air from the cooling unit 116. The exhaust outlet 130 may be configured in a closed position during the heating and recirculation phase of the device 100 as well as in the cooling phase.

[0035] In an example implementation, the housing 102 comprises a secondary inlet 134 to allow additional cooling medium to enter the housing 102. Examples of the additional cooling medium may include, but are not limited to, a cooling air and Nitrogen gas. The additional cooling medium may be introduced into the housing 102 during the cooling phase to allow to accelerate cooling of the heated air in addition to the cooling provided by the cooling medium introduced into the second channel of the cooling passage 120.

[0036] FIG. 2 illustrates a sectional view of an electrostatic precipitator 200 of a depyrogenation device, in accordance with an example implementation of the present subject matter. The electrostatic precipitator 200 may be similar to the electrostatic precipitator 106 of FIG. 1. The electrostatic precipitator 200 includes an enclosure 202 defining an inlet 204 and an outlet 206. The inlet 204 and the outlet 206 are similar to the inlet and an outlet as explained under the FIG. 1. The enclosure 202 accommodates a filtration unit arranged between the inlet 204 and the outlet 206. Further, the filtration unit comprises a charging terminal 208 which is disposed between the inlet 204 and the outlet 206 of the electrostatic precipitator 200. The charging terminal 208 is arranged to ionize particulate contaminants present in the air entering into the enclosure 202 through the inlet 204. The filtration unit further comprises a collection terminal 210 disposed between the charging terminal 208 and the outlet 206 of the electrostatic precipitator 200. The collection terminal 210 is arranged to collect the ionized particulate contaminants present in the air received from the charging terminal 208.

[0037] In an example, the enclosure 202 includes a pre-filter 212 placed at the inlet 204 to filter particulate contaminants present in the air. For example, the prefilter 212 is capable of filtering coarse particulate contaminants having a cross- sectional diameter of about 100 nm or above.

[0038] In addition, the electrostatic precipitator 200 comprises an outlet filter 214 disposed at the outlet 206. The outlet filter 214 is arranged to filter residual particulate contaminants from an air stream passing through the collection terminal 210. The residual particulate contaminants may be contaminants which are ionized by the charging terminal 208 but are not collected by the collection terminal 210.

[0039] In an example, the electrostatic precipitator 200 includes a first set of supply terminals (not shown) to supply power to the charging terminal 208. For example, the first set of supply terminals supplies a voltage of upto 8000 Volts direct current (DC) to the charging terminal 208 for ionization of the particulate contaminants. Further, the electrostatic precipitator 200 may include a second set of supply terminals (not shown) to supply power to the collection terminal 210. For example, the second set of supply terminals supplies a voltage of upto 4000 Volts DC to the collection terminal 210 for collection of the ionized particulate contaminants.

[0040] In an example, the electrostatic precipitator 200 may operate at a power specification of 30 milli-Ampere (mA) per square meter. The electrostatic precipitator 200 may support a cross-sectional velocity of the received heated air of approximately 0.5 meter per second.

[0041] FIG. 3A illustrates a pre-heating phase of the depyrogenation device 300, in accordance with an example implementation of the present subject matter. The depyrogenation device 300 as illustrated in FIG. 3A includes a housing 302 accommodating a receiving section 304, an electrostatic precipitator 306, a radiative heater 308, and a circulation unit 310. The structural and functional aspects of the housing 302 along with the receiving section 304, the electrostatic precipitator 306, the radiative heater 308, and the circulation unit 310 are similar to the housing 102 along with the receiving section 104, the electrostatic precipitator 106, the radiative heater 108, and the circulation unit 110 of FIG. 1. Therefore, for the sake of brevity, these components are not described in detail herein. Similarly, details of these components are not included in the description of FIG. 3B to 3E. In order to operate the device 300 in the pre-heating phase, upon placement of an article 350 in the receiving section 304, the radiative heater 308 is operated to provide heat to the receiving section 304 containing the article 350. In an example, a plurality of articles can be placed in the receiving section 304 for batch processing.

[0042] In the pre-heating phase, the radiative heater 308 may be operated to raise the ambient temperature of the receiving section 304 from a room temperature to a predefined temperature. In an example, the predefined temperature may be in a range of about 200° C to about 350° C. In the pre-heating phase, the circulation unit 310 and the electrostatic precipitator 306 are in a non-operating state. Further, the valve of the device 300, disposed on an inner wall of the housing 302 (described in detail under the description of FIG. 1), is in a closed position. In addition, the inlet valve and the outlet valve of the inlet and the outlet, respectively, of the cooling unit (described in detail under the description of FIG. 1) are configured in respective closed positions. Further, the exhaust valve of the exhaust outlet, the primary inlet of the cooling unit, and the secondary inlet of the housing 302 (described in detail under the description of FIG. 1) are configured in respective closed positions.

[0043] Raising the ambient temperature to the predefined temperature in the pre-heating phase allows for preparing the receiving section 304 for further processing steps of depyrogenation of the article 350 placed in the receiving section 304. The pre-heating phase allows to maintain the temperature in a surrounding region of the article 350 in an adequate range which is required for an efficient depyrogenation of the article 350.

[0044] FIG. 3B illustrates a heating and re-circulation phase of the depyrogenation device 300 of FIG. 3A, in accordance with an example implementation of the present subject matter. Upon completion of the pre-heating phase, the device 300 is operated in the heating and re-circulation phase. Before the initiation of the heating and re-circulation phase, the ambient temperature of the receiving section 304 is set at a required temperature as the predefined temperature, as achieved by the pre-heating phase, described in detail under the description of FIG. 3A.

[0045] In order to operate the device 300 in the heating and re-circulation phase, the valve of the device 300, disposed on an inner wall of the housing 302 (described in detail under the description of FIG. 1) is configured in an open position and the radiative heater 308 is operated to raise and maintain the temperature of the ambient air in the receiving section 304 at a desired temperature. In an example, the desired temperature may be in a range of about 250° C to about 350° C. Maintaining the temperature of the receiving section 304 in which the article 350 is placed at the desired temperature allows to inactivate pyrogenic substances and particles present on the article 350 by heating the air present in the surrounding of the article 350. The inactivation of the pyrogenic substances and particles may result in collection of residual material of the pyrogenic substances and particles on the article 350 and in the receiving section 304, in form of particulate contaminants. In addition, the circulation unit 310 is operated to circulate the heated air, heated by the radiative heater 308, from the receiving section 304 and from surface of the article 350. The circulation unit 310 circulates the heated air towards the inlet of the electrostatic precipitator 306 through the valve configured in the open position.

[0046] Further, the electrostatic precipitator 306 may be switched in an operating state. In the operating state, the electrostatic precipitator 306 may receive, through the inlet, the heated air containing the particulate contaminant, circulated by the circulation unit 310. In an example, the inlet includes a pre-filter for filtration of coarse particulate contaminants present in the heated air. Functioning of the prefilter is described in detail under the description of FIG. 2.

[0047] Further, the heated air is passed through a filtration unit of the electrostatic precipitator 306. The filtration unit is operated to ionize the particulate contaminants present in the heated air and collect the ionized particulate contaminants. The functioning of the elements of the filtration unit is described in detail under the description of FIG. 2.

[0048] In addition, the electrostatic precipitator 306 includes an outlet filter positioned at the outlet of the electrostatic precipitator 306. The outlet filter filters any residual particulate contaminants which may be present in the heated air received from the filtration unit. Upon filtration of the particulate contaminants, the filtered air is then ejected out from the outlet of the electrostatic precipitator 306. The ejected filtered air is directed towards the receiving section 304 in which the treated article 350 is placed. Upon continued circulation of the heated air inside the housing 302 and continued filtering of the particulate contaminants by the electrostatic precipitator 306, the pyrogens and residual material of the pyrogens are collected inside the electrostatic precipitator 306. Therefore, the successful depyrogenation of the article 350 is achieved. [0049] In the heating and re-circulation phase, the cooling unit is operably decoupled from the housing 302 by configuring the inlet valve and the outlet valve of the inlet and the outlet, respectively, of the cooling unit in respective closed positions. Further, the exhaust valve of the exhaust outlet, the primary inlet of the cooling unit, and the secondary inlet of the housing 302 are also configured in respective closed positions.

[0050] FIG. 3C illustrates a cooling phase of the depyrogenation device 300 of FIG. 3A, in accordance with an example implementation of the present subject matter. Upon completion of the heating and re-circulation phase, the device 300 is operated in the cooling phase. Before the initiation of the cooling phase, the ambient temperature of the receiving section 304 and the surrounding region of the article 350 is the predefined temperature, as maintained in the heating and re-circulation phase, described in detail under the description of FIG. 3B.

[0051] The device 300 is operated in the cooling phase for reducing the ambient temperature of the receiving section 304 and the surrounding region in which the article 350 is placed in order to reduce surface temperature of the article 350 for further usage of the article 350. In order to operate the device 300 in the cooling phase, the valve of the device 300, disposed on an inner wall of the housing 302 (described in detail under the description of FIG. 1) is closed and the radiative heater 308 is switched OFF to decrease the temperature of the ambient air in the receiving section 304. In an example, the cooling phase is activated to achieve a room temperature inside the receiving section 304.

[0052] In the cooling phase, the cooling unit is operably coupled to the housing 302 by configuring the inlet valve and the outlet valve of the inlet and the outlet, respectively, of the cooling unit in respective open positions. Further, the exhaust valve of the exhaust outlet and the secondary inlet of the housing 302 are maintained in respective closed positions. Upon opening of the inlet valve and the outlet valve, the heated air from the receiving section 304 is circulated, by the circulation unit 310, towards the inlet of the cooling unit. The inlet then directs the heated air towards a cooling passage of the cooling unit. [0053] Further, a primary inlet of the cooling unit is configured in an open position for introducing a cooling medium into the cooling passage. Introduction of the cooling medium causes reduction in the temperature of the heated air (described in detail under the description of FIG. 1). Further, the cooled air, treated by the cooling medium, is directed towards the inlet of the electrostatic precipitator 306. The electrostatic precipitator 306 then filters the cooled air received from the outlet of the cooling unit before directing the cooled and filtered air to the receiving section 304. The cooled air, directed from the electrostatic precipitator 306, comes in contact with the article 350. Upon contacting, the cooled air causes decrease in the surface temperature of the article 350 through heat transferring from the heated surface of the article 350 to the cooled air.

[0054] FIG. 3D illustrates a cooling phase of the depyrogenation device 300 of FIG. 3A, in accordance with an example implementation of the present subject matter. In addition to the cooling provided to the article 350, as described under the description of FIG. 3C, a secondary inlet of the housing 302 of the device 300 is configured in an open position. The secondary inlet is configured to provide another cooling medium to the housing 302. The cooling medium is provided in addition to the cooling medium introduced to the cooling passage by the primary inlet, as described under the description of FIG. 3C. Providing a secondary cooling medium allows for further decreasing of the temperature of the article 350 in a quick manner.

[0055] FIG. 3E illustrates an exhaust phase of the depyrogenation device 300 of FIG. 3A, in accordance with an example implementation of the present subject matter. Upon completion of the cooling phase, the device 300 is operated in the exhaust phase. Before the initiation of the exhaust phase, the ambient temperature of the receiving section 304 and the surrounding region of the article 350 is decreased to a room temperature, as achieved in the cooling phase, described in detail under the description of FIG. 3D.

[0056] The device 300 is operated in the exhaust phase to eject out the air from the housing 302 to an ambient environment in which the device 300 is placed. In order to operate the device 300 in the exhaust phase, the valve of the device 300, disposed on an inner wall of the housing 302 (described in detail under the description of FIG. 1) is configured in a partially open position in order to provide a pressure balance inside the housing 302 while the exhaust phase is executed. Further, the radiative heater 308 is maintained in a non-operating state.

[0057] In the exhaust phase, the inlet valve of the inlet of the cooling unit is in the open position whereas the outlet valve of the outlet is configured in a closed position. Further, the exhaust valve of the exhaust outlet and the secondary inlet of the housing 302 are configured in respective open positions. Upon opening of the inlet valve and the outlet valve, the air from the receiving section 304 is circulated, by the circulation unit 310, towards the inlet of the cooling unit. The inlet then directs the air towards a cooling passage of the cooling unit and then, in turn toward the exhaust outlet.

[0058] The air ejected out from the exhaust outlet is the filtered air which is continuously filtered by the electrostatic precipitator 306 during the previous phases. Therefore, treatment of the air prior to ejecting out from the exhaust allows to maintain a quality of the ambient air by preventing ejection of particulate contaminants from within the housing 302. Further, upon completion of the depyrogenation process, the electrostatic precipitator 306 can be easily cleaned for safe removal of the filtered and collected pyrogenic substances and material along with their residual elements.

[0059] FIGS. 4A to 4D illustrate a method 400 for operating the depyrogenation device of FIG. 1, in accordance with an example implementation of the present subject matter. The depyrogenation device (hereinafter also mentioned as ‘device’) comprising a housing to accommodate a receiving section, an electrostatic precipitator, a radiative heater, and a circulation unit similar to the elements as described in detail under the respective descriptions of FIGS. 1 to 3E. Each step of the method 400 is further explained in detail below. At step 402, in a pre-heating phase, upon placement of the article on a platform of the receiving section adjacent to an outlet of the electrostatic precipitator, a radiative heater is operated to heat ambient air in the receiving section up to a first predefined temperature range. In an example, the radiative heater is positioned above the platform. Further, at step 404, in a heating and recirculation phase, the radiative heater is operated to maintain a temperature of the ambient air in the receiving section at a second predefined temperature range.

[0060] At step 406, the circulation unit is operated to circulate the heated air from the receiving section towards the inlet of the electrostatic precipitator.

[0061] Further, at step 408, a filtration unit of the electrostatic precipitator is operated to filter and collect particulate contaminants present in the circulated heated air.

[0062] Referring to FIG. 4B, at step 408, in the heating and recirculation phase, filtering and collecting of the particulate contaminants comprises, at step 410, receiving, through an air inlet of the electrostatic precipitator, the heated air circulated by the circulation unit from the receiving section.

[0063] At step 412, in order to receive the heated air, circulated by the circulation unit, a valve, disposed on an inner wall of the housing, is operated between an open position and a closed position to selectively allow recirculation of air from the circulation unit towards the electrostatic precipitator.

[0064] Further, at step 414, particulate contaminants present in the circulated heated air received from the receiving section are ionized by a charging terminal of the electrostatic precipitator.

[0065] At step 416, the ionized particulate contaminants are collected by a collection terminal of the electrostatic precipitator.

[0066] At step 418, residual particulate contaminants from an air stream passing through the collection terminal are filtered, by an outlet filter of the electrostatic precipitator.

[0067] Now referring to FIG. 4C, at step 420, in a cooling phase, upon filtering and collecting the ionized particulate contaminants from the receiving section, at step 422, a cooling unit, which is operably coupled with the circulation unit and the electrostatic precipitator, is operated to cool the heated air received from the circulation unit and to provide the cooled air to the electrostatic precipitator to decrease an ambient temperature of the receiving section.

[0068] At step 424, an inlet valve of the inlet, operable between an open position and a closed position, is operated to receive the heated air from the circulation unit, the inlet being coupled with the housing.

[0069] At step 426, a flow of a cooling medium is allowed through a cooling passage. The cooling passage is fluidly connected to the inlet at a first end.

[0070] At step 428, the flow of the cooling medium is allowed through the cooling passage by a primary inlet of the cooling unit.

[0071] At step 430, an outlet valve of the outlet is operated between an open position and a closed position to introduce the lowered temperature air into the electrostatic precipitator. The outlet is arranged to provide a fluid connection between the cooling passage and the housing.

[0072] At step 432, another cooling medium is allowed, by a secondary inlet of the housing, to enter the housing.

[0073] Now referring to FIG. 4D, at step 434, in an exhaust phase upon completion of the cooling phase, at step 436, an exhaust valve of the exhaust outlet is operated between an open position and a closed position to eject exhaust air from the cooling unit.

[0074] Although examples for the present disclosure have been described in language specific to structural features and/or methods, it is to be understood that the appended claims are not limited to the specific features or methods described herein. Rather, the specific features and methods are disclosed and explained as examples of the present disclosure.

Claims

We claim:

1. A device for depyrogenating an article, the device comprising: a housing to accommodate: a receiving section having a platform to receive the article; an electrostatic precipitator having an inlet, a filtration unit, and an outlet, wherein the outlet is positioned adjacent to the receiving section; a radiative heater, positioned above the platform, to heat air in the receiving section; and a circulation unit to circulate the heated air from the receiving section towards the inlet of the electrostatic precipitator, wherein the filtration unit is to filter and collect particulate contaminants present in the circulated heated air.

2. The device as claimed in claim 1, wherein the filtration unit of the electrostatic precipitator comprises: a charging terminal disposed between the inlet and the outlet of the electrostatic precipitator, the charging terminal is to ionize particulate contaminants in the circulated heated air received from the receiving section; and a collection terminal disposed between the charging terminal and the outlet of the electrostatic precipitator, the collection terminal is to collect the ionized particulate contaminants.

3. The device as claimed in claim 2, wherein the electrostatic precipitator comprises: an outlet filter disposed at the outlet, the outlet filter is to filter residual particulate contaminants from an air stream passing through the collection terminal.

4. The device as claimed in claim 1, wherein the device comprises a valve disposed on an inner wall of the housing, the valve is operable between an open position and a closed position to selectively allow recirculation of air from the circulation unit towards the electrostatic precipitator.

5. The device as claimed in claim 1, wherein the device comprises a cooling unit, operably coupled with the circulation unit and the electrostatic precipitator, to cool the heated air received from the circulation unit and provide the cooled air to the electrostatic precipitator to decrease an ambient temperature of the receiving section.

6. The device as claimed in claim 5, wherein the cooling unit comprises: an inlet coupled with the housing to receive the heated air from the circulation unit, the inlet includes an inlet valve operable between an open position and a closed position; a cooling passage, fluidly connected to the inlet at a first end, to allow flow of a cooling medium therethrough, wherein the cooling medium is to lower a temperature of the heated air; and an outlet to provide a fluid connection between the cooling passage and the housing, wherein the outlet includes an outlet valve operable between an open position and a closed position to introduce the lowered temperature air into the electrostatic precipitator.

7. The device as claimed in claim 6, wherein the cooling unit comprises an exhaust outlet projecting outwards from the outlet and extending away from the housing, the exhaust outlet includes an exhaust valve operable between an open position and a closed position to eject exhaust air from the cooling unit.

8. The device as claimed in claim 6, wherein the cooling unit comprises a primary inlet to allow the cooling medium to enter the cooling passage.

9. The device as claimed in claim 8, wherein the housing comprises a secondary inlet to allow another cooling medium to enter the housing.

10. The device as claimed in claim 9, wherein the another cooling medium is one of a cooling air and Nitrogen gas.

11. The device as claimed in claim 1, wherein the radiative heater is an Infrared (IR) heater.

12. The device as claimed in claim 11, wherein the radiative heater is one of a twin tube infrared heater and a twin tube carbon fibre infrared lamp.

13. The device as claimed in claim 1, wherein the circulation unit is a blower.

14. The device as claimed in claim 5, wherein the cooling unit is a heat exchanger.

15. A method for operating a device for depyrogenating an article, the device comprising a housing to accommodate a receiving section, an electrostatic precipitator, a radiative heater, and a circulation unit, the method comprising: in a pre-heating phase: upon placement of the article on a platform of the receiving section adjacent to an outlet of the electrostatic precipitator, operating a radiative heater, positioned above the platform, to heat ambient air in the receiving section up to a first predefined temperature range. in a heating and recirculation phase: operating the radiative heater to maintain a temperature of the ambient air in the receiving section at a second predefined temperature range; operating the circulation unit, to circulate the heated air from the receiving section towards an inlet of the electrostatic precipitator; and operating a filtration unit of the electrostatic precipitator to filter and collect particulate contaminants present in the heated air being circulated.

16. The method as claimed in claim 15, wherein the operating the filtration unit comprises: receiving, through an air inlet of the electrostatic precipitator, the heated air circulated by the circulation unit from the receiving section; ionizing, by a charging terminal of the electrostatic precipitator, particulate contaminants in the heated air being circulated received from the receiving section; and collecting, by a collection terminal of the electrostatic precipitator, ionized particulate contaminants.

17. The method as claimed in claim 16, wherein the operating the filtration unit comprises: filtering, by an outlet filter of the electrostatic precipitator, residual particulate contaminants from an air stream passing through the collection terminal.

18. The method as claimed in claim 15, wherein the receiving of the heated air circulated by the circulation unit from the receiving section, comprises: operating a valve, disposed on an inner wall of the housing, between an open position and a closed position to selectively allow recirculation of air from the circulation unit towards the electrostatic precipitator.

19. The method as claimed in claim 15, wherein the method comprises: in a cooling phase, upon filtering and collecting the ionized particulate contaminants from the receiving section: operating a cooling unit, operably coupled with the circulation unit and the electrostatic precipitator, to: cool the heated air received from the circulation unit; and provide the cooled air to the electrostatic precipitator to decrease an ambient temperature of the receiving section.

20. The method as claimed in claim 19, wherein the cooling unit comprises an inlet, a cooling passage, and an outlet, and wherein, in the cooling phase, the operating of the cooling unit to cool the heated air comprises: operating an inlet valve of the inlet operable between an open position and a closed position to receive the heated air from the circulation unit, the inlet being coupled with the housing; allowing a flow of a cooling medium through a cooling passage, the cooling passage being fluidly connected to the inlet at a first end; and operating an outlet valve of the outlet between an open position and a closed position to introduce the lowered temperature air into the electrostatic precipitator, the outlet is to provide a fluid connection between the cooling passage and the housing.

21. The method as claimed in claim 20, wherein the cooling unit comprises an exhaust outlet projecting outwards from the outlet and extending away from the housing, and wherein the method comprises: in an exhaust phase upon completion of the cooling phase: operating an exhaust valve of the exhaust outlet between an open position and a closed position to eject exhaust air from the cooling unit.

22. The method as claimed in claim 20, wherein the method comprises: in the cooling phase: allowing, by a primary inlet of the cooling unit, the cooling medium to enter the cooling passage.

23. The method as claimed in claim 22, wherein the method comprises: in the cooling phase: allowing, by a secondary inlet of the housing, another cooling medium to enter the housing.