U.S. patent application number 15/031374 was filed with the patent office on 2016-09-29 for ventilation system.
The applicant listed for this patent is RECO-AIR LIMITED. Invention is credited to Nigel DICKENS, David TIDD.
Application Number | 20160281996 15/031374 |
Document ID | / |
Family ID | 49727235 |
Filed Date | 2016-09-29 |
United States Patent
Application |
20160281996 |
Kind Code |
A1 |
DICKENS; Nigel ; et
al. |
September 29, 2016 |
VENTILATION SYSTEM
Abstract
A ventilation system for cleaning contaminated heated air
generated by cooking appliances in a food preparation area, such as
a kitchen, includes an inlet for contaminated heated air located in
the food preparation area, a treatment part for cleaning the
contaminated heated air, and an outlet for the cleaned heated air.
The cleaned heated air is used as a heat source to heat the
building in which the food preparation area is located.
Inventors: |
DICKENS; Nigel;
(Staffordshire, GB) ; TIDD; David; (Staffordshire,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
RECO-AIR LIMITED |
Staffordshire |
|
GB |
|
|
Family ID: |
49727235 |
Appl. No.: |
15/031374 |
Filed: |
October 23, 2014 |
PCT Filed: |
October 23, 2014 |
PCT NO: |
PCT/GB2014/053160 |
371 Date: |
April 22, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F24C 15/2042 20130101;
F24C 15/2035 20130101 |
International
Class: |
F24C 15/20 20060101
F24C015/20 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 23, 2013 |
GB |
1318751.3 |
Claims
1. A ventilation system for cleaning contaminated heated air
generated by cooking appliances in a food preparation area such as
a kitchen, comprising: an inlet for contaminated heated air located
in the food preparation area; a treatment part for cleaning
contaminated heated air; and an outlet for the heated air; wherein
the heated air is used as a heat source to heat the building in
which the food preparation area is located.
2. A ventilation system as claimed in claim 1, wherein the outlet
for the heated air is located in a region of the building which it
is desired to heat.
3. A ventilation system as claimed in claim 2, wherein the outlet
for the heated air is located in a dining area associated with the
food preparation area, and the heated air is used to heat the
dining area.
4. A ventilation system as claimed in claim 1, wherein the
treatment part is provided with means for cooling the air.
5. A ventilation system as claimed in claim 1, with one or more
fans in the treatment part for creating a current of air from the
inlet to the outlet.
6. A ventilation system as claimed in claim 1, wherein the
treatment part cleans the contaminated air by filtering it.
7. A ventilation system as claimed in claim 6, wherein a series of
filters are used.
8. A ventilation system as claimed in claim 7, wherein a monitoring
system monitors the state of the filters.
9. A ventilation system as claimed in claim 8, wherein the
monitoring system includes transducers for measuring the pressure
drop across the filters.
10. A ventilation system as claimed in claim 8 further comprising a
fan, wherein the monitoring system can control the speed of the fan
depending on the state of the filters.
11. A ventilation system as claimed in claim 8, wherein the
monitoring system can send wireless alerts depending on the state
of the filters.
12. A ventilation system as claimed in claim 8, wherein the
monitoring system can be accessed remotely.
13. A ventilation system as claimed in claim 1, wherein the
treatment part also includes means for removing odours from the
contaminated air.
14. A ventilation system as claimed in claim 13, wherein said means
include activated charcoal.
15. A ventilation system as claimed in claim 1, wherein the
treatment part is located in a room separate from the food
preparation area.
16. (canceled)
Description
[0001] The present invention relates to a ventilation system for
use in a food preparation area such as a commercial kitchen, and
more particularly to a ventilation system in which hot air from
cooking appliances is treated and returned to the food preparation
area or to another area of the building where the food preparation
area is located.
[0002] A commercial kitchen (such as a kitchen in a restaurant)
normally includes an electric (or gas) cooking line, with several
cooking appliances (such as ovens, griddles, burners, fryers and
the like). These heat the air, introduce cooking odours into the
air, and, particularly in the case of fryers, contaminate it with
smoke, droplets of oil and grease, and the like. This heated and
contaminated air needs to be removed in order for the kitchen to
remain an acceptable working environment. Similar issues arise with
other food preparation areas, such as bakeries.
[0003] Removal of the heated and contaminated air is routinely
carried out by means of purpose-made canopies or hoods above the
appliances. These hoods are normally provided with grease filters,
and are connected to accessible ducts, usually located above the
hood and running through the ceiling space to a dedicated fan set,
which is normally positioned on the roof of the building in which
the kitchen is located. The fan is operated to discharge air from
the ducts to the outside of the building, and this creates a lower
pressure in the ducts which in turn helps evacuate the heated and
contaminated air collected in the hoods.
[0004] However, the discharge of air from the ducts to the
atmosphere outside the building can be undesirable. If cooking
odours or contaminants are not removed before the air is
discharged, the environment around the building can become
unpleasant, and some local authorities in the United Kingdom refuse
to allow new developments of food premises to discharge to the
atmosphere.
[0005] A further problem with discharging the air to the atmosphere
outside is that if all of the air sucked into the hoods were to be
discharged in this way, this would result in a considerable fresh
air make-up requirement to replace the discharged air. Further,
heat in the discharged air is wasted, and the need to add heat to
the make-up air in order to maintain a comfortable environment for
the kitchen staff increases running costs. Normally, a small amount
of the air (around 20 percent) is discharged, and the remainder is
combined with make-up air/replacement air taken from the
atmosphere, filtered, heated and returned to the kitchen; however,
this still leads to wasted heat and increased running costs.
[0006] Furthermore, the need to provide ductwork to discharge air
to atmosphere (and, if required, to bring make-up air in from the
atmosphere outside the building) causes further problems. Often,
the ducts will need to be located in risers, which imposes
limitations on the possible layouts of the ductwork. Further, the
ductwork in the riser will need to be made fireproof, increasing
costs.
[0007] It is an object of at least the preferred embodiments of the
invention to provide a ventilation system for food preparation
areas such as kitchens that allows a more efficient use of the heat
generated in cooking.
[0008] According to a first aspect of the present invention, there
is provided a ventilation system for cleaning contaminated heated
air generated by cooking appliances in a food preparation area such
as a kitchen, comprising: an inlet for contaminated heated air
located in the food preparation area; a treatment part for cleaning
contaminated heated air; and an outlet for the heated air; wherein
the heated air is used as a heat source to heat the building in
which the food preparation area is located.
[0009] In the ventilation system of the invention, all of the
heated contaminated air entering the inlet in the food preparation
area is cleaned, and is retained in the building in which the food
preparation area is located rather than being discharged to
atmosphere. This avoids any problems associated with atmospheric
discharge.
[0010] Further, as none of the air is discharged to atmosphere,
none of the heat generated by the cooking appliances is lost, and
all of it can be used to heat the building. This allows a more
efficient use of the "waste" heat generated in cooking, and can
significantly reduce heating costs for the building.
[0011] Furthermore, there is no need to supply any make-up air to
replace discharged air, and so the ductwork which is normally
required to supply make-up can be dispensed with, reducing
installation costs. In addition, the energy which would have been
required to heat the make-up air can be saved, thus reducing
running costs.
[0012] The heated air can be used as a heat source in any suitable
manner. In a simple arrangement, the outlet for the heated air is
located in a region of the building which it is desired to
heat.
[0013] In a preferred form, the outlet for the heated air is
located in a dining area associated with the food preparation area,
and the heated air is used to heat the dining area.
[0014] This can be particularly useful in "open-plan" dining areas,
such as those found in shopping malls and the like. Heated air
generated by a food preparation area can be discharged from the
outlet into the dining area to heat it, and there can be multiple
outlets for the heated air to provide a more uniform heating
effect. Discharge can, in certain locations, take place at floor
level.
[0015] At certain times of the year, the heated air returned to the
space to be heated would be considered to be too hot, and would
lead to discomfort. To avoid this, the treatment part may be
provided with means for cooling the air. With such an arrangement,
the temperature of the discharged air can be lower than the
temperature of the air entering the inlet, to maintain acceptable
comfort levels.
[0016] Any suitable means can be provided for cooling the air. In a
preferred form, the hot air can be cooled in a direct exchange or
chilled water cooling coil, connected to suitable heat injection
equipment at roof level, before being discharged from the unit.
[0017] Air can be made to move through the treatment part in any
suitable manner. However, in a preferred form, one or more fans are
provided in the treatment part for creating a current of air from
the inlet to the outlet.
[0018] The air can be cleaned in any suitable manner. However, it
is preferred for the treatment part to clean the contaminated air
by filtering it. Filtration is a well known method of cleaning air,
and the filter or filters used can be tailored to the particular
requirements of the installation.
[0019] Preferably, a series of filters are used. This allows better
tailoring of the filtration to the requirements of the
installation, rather than relying on a single filter.
[0020] As the filters will become clogged with removed contaminants
after a prolonged period of use, they can be replaced after a
certain period. However, it is preferred for the ventilation system
to include a monitoring system which monitors the state of the
filters.
[0021] With this arrangement, the installed life of the filters can
be extended, as they will only be replaced when such replacement is
actually necessary, rather than being replaced at specific times in
accordance with a preset schedule.
[0022] Any suitable system for monitoring the state of the filters
can be used. In a preferred form, the monitoring system includes
transducers for measuring the pressure drop across the filters. As
the filters become clogged, the pressure drop across them
increases, and so the pressure drop across the filters allows the
filter lifespan to be accurately determined.
[0023] In a preferred form, the monitoring system can control the
speed of the fan depending on the state of the filters. For
example, if the monitoring system has noted that a filter is
becoming clogged with contaminants and will soon need to be
replaced, the speed of the fan can be changed (for example,
increased to maintain a predetermined air flow) until such time as
the filter is replaced.
[0024] The monitoring system may be connected to a display panel on
the treatment part, and can switch on lights (such as an amber or
red light), to indicate that a filter should be or must be
replaced.
[0025] In a preferred form, the monitoring system can send wireless
alerts depending on the state of the filters. This allows a person
in charge of maintenance of the system to be alerted to the need to
change a filter, even if the person is not near the treatment part
at the time.
[0026] It also preferred for the monitoring system to be accessible
remotely. This allows a single maintenance operative to check on
the state of the filters in several different installations from a
single location, such as a central office.
[0027] In a preferred form, the treatment part also includes means
for removing odours from the contaminated air. These can take any
suitable form, but preferably include activated charcoal.
[0028] In a preferred form, the treatment part is located in a room
separate from the food preparation area. By locating the treatment
part in a room separate from the food preparation area, the amount
of space required in the food preparation area itself can be
reduced.
[0029] Further, maintenance of the treatment part may require the
use of materials which should, ideally, be kept separate from food
to prevent possible contamination of the food. Locating the
treatment part in a room separated from the food preparation area
allows maintenance to be carried out without the risk of such
contamination, and without disturbing operations in the food
preparation area.
[0030] A preferred embodiment of the invention will now be
described with reference to the accompanying drawings, in
which:
[0031] FIG. 1 is a schematic view of a first embodiment of a
ventilation system according to the present invention, used to
ventilate a kitchen;
[0032] FIG. 2 shows a treatment part of the ventilation system, in
which the air is filtered; and
[0033] FIG. 3 is a schematic view of a second embodiment of a
ventilation system according to the present invention.
[0034] As shown in FIG. 1, the ventilation system 10 according to
the first embodiment includes two main parts; an intake part 100,
located in a kitchen 20 to be ventilated, and a treatment part 200,
which in this case is located in a separate room 30. The treatment
part 200 can also be located in the kitchen 20 to be ventilated, if
necessary, but this is less desirable. The kitchen includes a
number of cooking appliances 22 (shown schematically in FIG.
1).
[0035] FIG. 1 shows the treatment part 200 in a room 30 adjacent to
the kitchen 20 to be ventilated (on the other side of a wall 40);
the treatment part 200 does not need to be located adjacent to the
kitchen 20, but such an arrangement reduces the ducting required to
implement the system.
[0036] As shown in FIG. 2, the treatment part 200 of the
ventilation system 10 includes a fan 210, which is operated to draw
air through the treatment part from an inlet 220 to an outlet 230.
FIG. 1 shows that the inlet 220 of the treatment part 200 is
connected to ductwork 50 extending from the kitchen 20 through the
wall 40 into the adjacent room 30, and this ductwork 50 in turn has
one or more inlets 52 positioned above the cooking appliances 22,
so that heated and contaminated air can be drawn into the ductwork
50 when the fan 210 is operated.
[0037] The outlet 230 of the treatment part 200 is connected to
further ductwork 60 which extends away from the treatment part 200.
All of the air entering the inlets 52 of the ductwork 50 above the
cooking appliances 22 is drawn into the treatment part 200 by the
fan 210, treated in the treatment part 200 (as will be described in
detail later), and then passes through the further ductwork 60.
This further ductwork can be connected to an outlet in an area in
the building that requires heating, so that the cleaned heated air
can heat that area. There is thus no need for a route to the
outside of the building, as would be required with a conventional
system.
[0038] Although the inlet 220 and outlet 230 of the treatment part
are shown at different heights in FIG. 2, it will be appreciated
that they can be at the same height (as in FIG. 3), depending on
the particular requirements of the specific installation.
[0039] As mentioned in the introduction, the cooking appliances 22
heat the air, and introduce cooking odours and other contaminants.
The heated and contaminated air is filtered in the treatment part
200 to remove contaminants and odours.
[0040] A series of filters 240 are located between the inlet 220 of
the treatment part 200 and the fan 210. The first of these filters
242 serves to filter out heavy particulates from the incoming air
(low grade grease filtration), the second 244 filters out light
particulates (high grade grease filtration), and the third 246
filters out smoke. The third filter 246 may be a HEPA (high
efficiency particle arrestor) filter.
[0041] Each of the filters 242, 244, 246 can be replaced
independently of the other two. The first filter 242 will normally
need to be replaced more frequently than the second filter, which
in turn will need to be replaced more frequently than the third
filter (for example, the first filter may need to replaced every
month, the second filter may need to be replaced every three
months, and the third filter may need to be replaced every six
months.)
[0042] The first and second filters 242, 244 remove grease from the
air which passes through them, and this grease will accumulate on
the filters. If the design of the filter allows it, it may be
possible to remove the accumulated grease and convert it into
bio-fuel.
[0043] A monitoring system 250 (shown very schematically in the
Figures) is provided to monitor the state of each filter 242, 244,
246, so that an alert can be sent to a user of the system when (or,
more preferably, just before) each filter requires replacement. The
system may use pressure transducers to determine the pressure drop
across the filters, as this pressure drop will vary depending on
the state of the filter.
[0044] The alerts can be sent wirelessly to a wireless device of
the user (such as a smartphone or tablet), so that the user does
not need to be permanently on-site. The alerts can also be sent to
a central management site.
[0045] Monitoring dials or similar displays (such as a "traffic
light" type system) can be provided on the treatment part, so that
a local user can see the state of the filters. In addition, it is
preferably possible for the monitoring system to be accessed
online, ideally from a wireless device, so that the state of the
filters can be monitored remotely in a "live" manner.
[0046] The monitoring system 250 can also be connected to the fan
210, and can vary the power of the fan depending on the state of
the filters 240. For example, if the monitoring system notes that a
filter is clogged with contaminants (such as grease) and needs to
be replaced, the speed of the fan can be changed (for example,
increased) until the filter has been replaced.
[0047] Further, the monitoring system 250 can be arranged to shut
the system down in the event of a serious problem such as a total
blockage of one or more of the filters 240. Sensors can be provided
in the ductwork 60 which discharges air from the treatment part to
monitor the quality and temperature of the cleaned air.
[0048] The monitoring system 250 can also include a fire detection
system, which activates an independent fire extinguishing system if
a fire is detected in the ventilation system 10.
[0049] Between the fan 210 and the outlet 230 of the treatment part
200 are located a series of activated charcoal filters 260. These
are intended primarily to remove odours from the air. Again, the
filters 260 can be replaced independently of each other, and of the
filters 240. It is expected that the filters 260 will need to
replaced annually.
[0050] In some situations, the charcoal filters may not be
required. For example, if the ventilation system is used to remove
heated and contaminated air from a bakery in a shopping mall, it
may be desirable to retain the odour of baking bread in the
discharged air.
[0051] Preferably, the treatment unit can only be opened (to allow
access to the filters and fan) by an approved maintenance
operative; this can be achieved simply by providing locks on the
unit, and giving keys to the approved operative. Further, for
safety reasons, it is preferred for the system to be arranged such
that the fan cannot operate if the unit is open, or of one (or
more) of the filters are not present.
[0052] FIG. 3 shows an alternative arrangement of a ventilation
system, again used to extract heated contaminated air from a
kitchen. Here, the system includes three main parts; an intake part
(in the form of a kitchen extract canopy) 300, the treatment part
200, and a discharge part 320. The intake part 300 is located in a
kitchen area, above the cooking appliances (which are not shown in
FIG. 3). The treatment part 200 is located in a separate room,
adjacent to the kitchen, and is connected to the kitchen extract
canopy by kitchen extract ductwork (corresponding to ductwork 50 in
FIG. 1).
[0053] The discharge part 320 is located in a dining area, which in
this case is adjacent to the kitchen and the room housing the
treatment part 200. It is connected to the treatment part 200 by
supply ductwork (corresponding to ductwork 60 in FIG. 1).
[0054] FIG. 3 shows that the discharge part 320 includes several
outlets 330 for the heated air. The number, size and location of
the outlets can be varied depending on the heating requirements of
the dining area. The outlets can be provided at floor level, or at
high level, to blow heated air down in the space.
[0055] The supply ductwork can also extend into the kitchen, as
shown in FIG. 3. If all of the air removed from the kitchen is
discharged elsewhere (whether to atmosphere as in prior systems or
to a dining area), this may lead to a strong air current through
the building into the kitchen to replace the discharged air (unless
steps are taken to introduce make-up air into the kitchen).
Returning some of the cleaned air to the kitchen reduces this
current (and reduces the need to introduce make-up air). As shown
in FIG. 3, dampers 340 can be provided in the supply ductwork to
allow the proportion of the heated air going to the dining area and
the kitchen to be varied.
[0056] Sometimes (for example, during summer), it may not be
desired to simply discharge the heated air into the dining area, as
this may lead to the dining area becoming uncomfortably hot. Thus,
it is preferred for the treatment part to be provided with means
for cooling the air. This allows the temperature of the discharged
air to be lower than the temperature of the air entering the
inlet.
[0057] Preferred embodiments of the ventilation system have been
described in the context of ventilation of a food preparation area,
and specifically a kitchen. However, it will be appreciated that
the system could be used to ventilate other rooms in which heated
contaminated air is produced, such as workshops. The system could
also be used in a domestic kitchen.
[0058] Further, it will be appreciated that arrangements of the
ventilation system other than those shown in the Figures can be
used. For example, the treatment part can be located in a ceiling
void, or on the roof of the building, to make use of available but
previously unused space.
* * * * *