FORM2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
1. Title of the invention: DEVICES AND METHODS FOR DEPYROGENATION
2. Applicant(s)
NAME NATIONALITY ADDRESS
PHARMALAB INDIA PVT.
LTD.
Indian Kasturi, Sanghvi Estate, Govandi
Station Road, Govandi (E),
Mumbai Maharashtra 400 088,
India
3. Preamble to the description
COMPLETE SPECIFICATION
The following specification particularly describes the invention and the manner in which it
is to be performed.

TECHNICAL FIELD
[0001] The present subject matter relates, in general, to
depyrogenation, and, particularly, to a depyrogenation device and a method
5 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,
10 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
15 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;
20 [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. 3A, in accordance with an example
25 implementation of the present subject matter;
[0008] FIG. 3C illustrates a cooling phase of the depyrogenation device
of FIG. 3A, in accordance with an example implementation of the present
subject matter;

[0009] FIG. 3D illustrates a cooling phase of the depyrogenation device
of FIG. 3A, in accordance with an example implementation of the present
subject matter;
[0010] FIG. 3E illustrates an exhaust phase of the depyrogenation
5 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.
10 [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
15 [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
20 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
25 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
10 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 log10
reduction. For achieving the inactivation of the pyrogen through 3 log10
15 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
20 350°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
25 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
30 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
5 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
10 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
15 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
20 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
25 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
30 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
5 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
10 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
15 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 stainlesssteel surfaces and more hygienic construction is easily cleanable and
reusable with an indefinite life. Thus, an overall installation and operation
20 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
25 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
30 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
5 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
10 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
15 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.
20 [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
25 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
30 micrometers (µm) (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
5 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
10 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.
15 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
20 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
25 102 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
30 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
5 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
10 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
15 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
20 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
25 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
30 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
5 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
10 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.
15 [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.
20 [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
25 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
30 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
5 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.
10 [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
15 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
20 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.
25 [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
30 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
5 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
10 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 pre-filter 212 is capable of filtering coarse particulate
15 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
20 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
25 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
30 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.
5 [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
10 310. 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
15 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
20 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
25 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
30 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
5 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
10 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 pre15 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.
20 [0045] In order to operate the device 300 in the heating and recirculation 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
25 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
30 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
5 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
10 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 pre-filter is described in detail under the
description of FIG. 2.
15 [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.
20 [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
25 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
5 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
10 300 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,
15 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
20 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.
25 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.
30 Further, the exhaust valve of the exhaust outlet and the secondary inlet of
17
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
5 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,
10 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
15 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
20 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
25 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
30 device 300 of FIG. 3A, in accordance with an example implementation of
18
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
5 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
10 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.
15 [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
20 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
25 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
5 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
10 400 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.
15 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
20 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
25 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
20
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
5 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
10 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
15 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
20 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.
25 [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
21
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.
5 [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
10 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.
15
22
I 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;
5 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
10 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
15 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
20 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:
25 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
23
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
5 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
10 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
15 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
20 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
25 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.
24
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.
5 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
10 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
15 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
20 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
25 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;
25
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,
5 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
10 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
15 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:
20 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.
25 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
30 inlet being coupled with the housing;
26
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
5 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:
10 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:
15 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:
20 allowing, by a secondary inlet of the housing, another cooling
medium to enter the housing.