Note: Descriptions are shown in the official language in which they were submitted.
CA 02175294 1999-11-OS
2
LIQUID SPRAY AIR PURIFICATION AND
CONTROLLED HUMIDIFICATION APPARATUS
WITH AIR QUALITY MONITOR AND CONTROLLER
For related subject matter, see U.S. Patent
5,389,120 entitled "HEATING, VENTILATION AND AIR
CONDITIONING UNIT WITH AUTOMATICALLY CONTROLLED WATER
SPRAY AIR PURIFICATION SYSTEM".
BACKGROUND OF THE INVENTION
The present invention generally relates to
environmental control apparatus and, in a preferred
embodiment thereof, more particularly relates to an
improved liquid spray air purification and controlled
humidification system which is automatically operated
by a specially designed air quality monitor and
controller embodying principles of the present
invention.
Interior spaces of homes and other,buildings are
typically provided with automatically controlled
temperatures using one or more air handling units that
~~~J~~~~
3
provide a recirculating flow of air drawn out of the
conditioned space, flowed through the air handling unit
by an air blower therein, heated or cooled as necessary
within the unit, and then flowed back into the
conditioned space. In addition to providing the
desired temperature control within the conditioned
apace, air handling units of this general type are also
often provided with the capability of purifying, at
least to some extent, air flowing through the units.
The most common device used for this air
purification task is the familiar replaceable flow-
through air filter element that is disposed within the
unit cabinet structure in the path of air being forced
therethrough on its way back to the conditioned space
IS served by the unit. Filters of this type are typically
formed from a matted fibrous material (such as
fiberglass) that serves to trap particulate matter,
such as dust, borne in the conditioned space return air
entering the unit. Additionally, electrostatic air
filters are often incorporated in air handling units
and provide improved particulate removal performance
due to their electrostatic attraction and trapping of
particulates substantially smaller than the ordinary
fibrous filter can effectively capture.
However, as is well known, undesirable air
pollutants are present in a variety of forms other than
the relatively easy to capture particulates that the
fibrous and electrostatic filter structures are
designed to remove from the recirculated air from the
conditioned space. Another known type of air
purification process is the use of a liquid spray,
typically a water spray, directed against filter
element through which air to be supplied to a
conditioned space is flowed. The liquid spray is
2~°~~29~
4
maintained in continuous contact with the flowing air
traversing the filter element, and, depending on the
type of air purification system in which it is
incorporated, serves to entrain a variety of airborne
particulates as well as other types of pollutants such
as aerosols, nitrogen oxides, sulfur oxides, carbon
dioxides and monoxides, hydrogen sulfides and
hydrocarbons, and then be drained away carrying
entrained pollutants with it. This general type of air
purification system also desirably serves to humidify
the air delivered to the conditioned space.
Despite the pollution removing effectiveness of
various known types of liquid spray air purification
systems, their use has typically been limited to
industrial and commercial applications, as opposed to
residential applications, due to reasons such as
excessive humidity and lack of humidity control,
complexity, cost and increased maintenance requirements
compared to dry filtering systems. Because of the
increased awareness of air polluting materials, and the
desirability of removing them from residential
environments, it is seen as desirable to provide a
liquid spray air purification system that is suitable
for incorporation in residential as well ae commercial
applications. It is accordingly an object of the
present invention to provide such a system which will
(1) both purify the air and control the humidity of the
air delivered to a conditioned space and (2)
automatically monitor the air quality and control the
operation of the system to economically clean the air
and maintain the air quality, temperature, and humidity
within desired, selectively variable preset ranges.
SUMMARY OF THE INVENTION
~1°~529~
In carrying out principles of the present
invention, in accordance with a preferred embodiment
thereof, an air handling unit is provided that includes
a housing having an inlet opening, an outlet opening,
5 and an internal flow path extending between the inlet
opening and the outlet opening, and blower means for
sequentially flowing air inwardly through the inlet
opening, through the internal flow path, and outwardly
through the outlet opening. The air handling unit is
representatively illustrated in both HVAC unit and air
purification and controlled humidification unit
embodiments.
Air purification means are disposed in the
internal housing flow path, and are operative to
receive pressurized liquid from a source thereof,
create a spray from the received liquid, use the spray
to purify air traversing the internal housing flow
path, and then permit the sprayed liquid to drain
therefrom into sump means operative to hold a supply of
liquid to be operatively supplied to the air
purification means and receive liquid draining
therefrom.
The air handling unit further comprises filter
means having therein a filtering flow path through
which liquid may be forced to trap pollutants in the
filter means, and a backwashing flow path through which
liquid may be forced to cleanse the filter means of
trapped pollutants. A pump portion of the air handling
unit has an inlet communicatable with liquid in the
sump means, and an outlet. Conduit means interconnect
the pump outlet with the filtering flow path and the
backwashing flow path, and also interconnect the
filtering flow path with the air purification means.
Switching means are associated with the conduit
6
means and are selectively operative in a first mode to
cause sump liquid discharged from the pump to be forced
through the filtering flow path to the air purification
means, or in a second mode to cause sump liquid
discharged from the pump to be forced through the
backwashing flow path.
First monitoring means are provided for detecting
a change in an apparatus operating parameter,
indicative of a predetermined lessening in the
filtration efficiency of the filter means, and
temporarily changing the switching, means from their
first mode to their second mode. The first monitoring
means representatively are capable of detecting an
increase in pumping back pressure upstream of the
filter means as well as detecting particulate and/or
gaseous pollutants.
According to other features of the invention,
additional monitoring means are operative to sense a
decrease in the normal concentration of chemical
treatment additive in the sump liquid and/or a
predetermined level of chemically treatable pollutants
in the sump liquid and responsively inject a quantity
of chemical treatment additive into the sump liquid
from a source thereof, and dehumidification means are
provided in the housing, downstream from the air
purification means, and are operative to remove
moisture from air exiting the air purification means.
In a preferred embodiment thereof, the air
handling unit, which may representatively be a heating,
ventilation and air conditioning unit or an air
purification and controlled humidification unit,
further comprises means for sensing variations in the
temperature, humidity, suspended particles (total
suspended particulate matter, TSP), and other
2~~52~~
pollutants in the air being discharged by the blower
means within the housing and responsively causing
changes in operation of the air handling unit, the air
purification means, the air humidification and
dehumidification means, and/or the air cooling and
heating means which result in the system automatically
and economically cleaning, treating and/or conditioning
the air to achieve the ranges of temperature, humidity
and air quality preset by the user within a reasonable
time period.
Rather than the thermostat used to control a
conventional HVAC unit, the "Liquid-Spray Air
Purification and Controlled Humidification" (LSAPCH)
system uses an "Air Quality Monitor and Controller"
(AQMC). The AQMC is electrically coupled to the
sensing apparatus in the LSAPCH system which measures
temperature, humidity, suspended particles and other
pollutants in the air-being discharged by the blower
means. Such measurements are monitored by the AQMC and
when they are outside the ranges preset by the user,
the AQMC makes changes in the operation of the LSAPCH
to achieve the level of temperature, humidity,
suspended particles and other air quality parameters
desired.
The following is an example of the operation of
the LSAPCH system when measurements received by the
AQMC indicate that there is an excess humidity
condition in the air being discharged by the blower
means whereas the temperature, suspended particles, and
other air quality parameters are within the ranges
preset by the user. In this event, the AQMC would send
a signal to cause a portion of the discharged air to be
returned to and operatively flowed across the
dehumidification means before being forced outwardly
,~
~1~52~4
8
through the outlet opening by the blower means, to
thereby reduce the humidity of the air discharged from
the housing. The housing may be provided with a second
inlet opening, and the humidification control means may
be further operative, in response to sensing an excess
humidity condition in air being discharged by the
blower means within the housing, to responsively permit
the blower means to sequentially draw air inwardly
through the second inlet opening, into the interior of
the housing between the air purification means and the
dehumidification means, and across the dehumidification
means and into the fan inlet to further reduce the
humidity of the air discharged from the housing.
In a preferred embodiment thereof, temperature,
humidity, suspended particles and other air pollutants
(collectively Temperature, Humidity and Air Pollutants
or ~~THAP~~) are controlled within preset ranges by
signals automatically sent by the AQMC to various
components of the LSAPCH system. The LSAPCH system
includes (1) damper means operable to controllably vary
the flow of air through the air handling unit housing,
(2) means to measure THAP located in the downstream
portion of the LSAPCH system, (3) means to transmit
such measurements to AQMC, and (4) AQMC to monitor such
measurements and signal the damper means and/or other
components of LSAPCH to cause operation of such
components to clean, dehumidify, humidify, cool, or
heat the air as required to return the conditioned air
to the preset ranges of temperature, humidity, and air
quality. In addition to the sensing apparatus located
in the downstream portion of the LSAPCH system, a
similar sensing apparatus may be located in the
conditioned space external to the LSAPCH system to also
permit measurement of temperature, humidity, suspended
y
9
particles, and other pollutants in the air at room
conditions. Therefore, the AQMC can be set to control
the LSAPCH system based on measurements of temperature,
humidity, suspended particles, and/or other pollutants
of either (1) air being discharged by the blower means
of the LSAPCH system or (2) air at room conditions
external to the LSAPCH system.
BRIEF DESCRIPTION OF THE DRAPTINGS
FIG. 1 is a schematic side elevational view of a
representative heating, ventilation and air
conditioning unit in which an improved liquid spray air
purification system with a specially designed air
quality monitor and controller (AQMC) embodying
principles of the present invention is operatively
incorporated;
FIG_ 2 is an enlarged scale schematic cross-
sectional view through the unit, and its associated air
purification system, and illustrating in simplified
form the interconnection between the AQMC; the heating,
ventilation and air conditioning unit; and the liquid
spray air purification system;
FIG. 3 is an enlarged scale partially cut away
schematic side elevational view of a liquid sump
portion of the air purification system and illustrates
the operative coupling of the AQMC to the liquid sump
portion;
FIG. 4 is a partial top plan view of the liquid
sump portion shown in FIG. 3;
FIGS. 5A and 5B are schematic cross-sectional
views through a free standing liquid spray air
purification and humidification unit embodiment of the
present invention incorporating the AQMC, with FIG. 5A
illustrating the unit in its normal operating mode, and
FIG. 5B illustrating the unit in a
~~~J~~~
to
recirculating/blending operating mode thereof; and
FIG. 6 is a schematic side elevational view of an
alternative embodiment of the heating, ventilation and
air conditioning unit illustrated in FIG. 1 and
similarly incorporating the AQMC;
FIG. 7 is an enlarged scale front aide perspective
view of a control/diaplay panel portion of the AQMC;
and
FIG. 8 is a schematic block diagram of the AQMC;
and
FIG. 9 is a flow chart illustrating the operation
of a computer portion of the AQMC in monitoring and
controlling the operating parameters of an air delivery
and conditioning system into which the AQMC is
representatively incorporated.
DETAINED DESCRIPTION
Schematically depicted in FIGS. I and 2 is a
heating, ventilation and air conditioning (HVAC) unit
10 incorporating therein a specially designed liquid
spray air purification system 12 embodying principles
of the present invention. HVAC unit 10 serves an
interior space 14 disposed within a building 16 having
an exterior wall 18 and a roof 20. The conditioned
interior space I4 representatively has a vertical
interior wall 22 and a ceiling 24 spaced downwardly
apart from the roof 20. The unit 10 is supported
within the space 26 between the roof 20 the ceiling 24,
in a horizontal airflow orientation, on suitable
support members 28, such as metal hanger rods or
straps, secured to the roof structure. Rather
than the typical thermostat used to control a
conventional HVAC unit of this general type, the unit
10 together with the system 12 are monitored and
~i
~~~~z~~
11
controlled by a specially designed air quality
monitoring and control system 30 (hereinafter referred
to simply as the ~~AQMC°) embodying principles of the
present invention and which may be mounted on interior
wall 22.
AQMC 30 is electrically coupled to (1) a multi-
parameter sensing apparatus I00 operatively associated
with unit 10 and, as later described herein, including
instruments to measure the temperature, humidity and
suspended particles in the downstream portion of the
unit 10 ,as well as a gas analyzer to measure other
pollutants in the air in the downstream portion of unit
10, and (2) various components of the unit 10 and the
liquid spray air purification system 12 that are
selectively operated by AQMC 30 to achieve the level of
temperature, humidity, and air quality ranges that have
been preset as desired by the user. In addition to the
sensing apparatus 100 located in the downstream portion
of unit 10, a similar sensing apparatus may also be
located in theconditioned space external to the unit
10 and system 12. This permits the AQMC 30 to be set
to operate the unit 10 and the system 12 to achieve
preset temperature, humidity, suspended particles,
and/or other pollutants based on measurements of such
parameters either of (1) air being discharged by the
blower means of unit 10 and/or system 12 or (2) air at
room conditions external to the unit 10 and system 12.
Still referring to FIGS. 1 and 2, the AVAC unit 10
includes a horizontally elongated hollow rectangular
metal cabinet structure 32 having an open inlet end 34
and an open outlet end 36. From right to left as
viewed in FIG. 2 the HVAC unit 10 has operatively
disposed within its cabinet 32 a return air damper
structure 38 adjacent the cabinet inlet end 34; a
~i
~~~~29~
12
replaceable cartridge type air filter 40; a supply air
blower 42; a heat exchanger 44; and a cooling coil 46.
Representatively, the heat exchanger 44 is a fuel-fired
heat exchanger having a burner structure 47 operatively
associated therewith, and the cooling coil is of the
direct expansion refrigerant type and is connected to
conventional air conditioning refrigerant circuitry
(not illustrated).
A return air duct 48 is interconnected between the
IO cabinet inlet end 34 of the HVAC unit 10 and a suitable
return air grille 50 mounted on the underside of the
ceiling 24. At the opposite end of the unit 10 a main
supply air duct 52 is connected to the cabinet outlet
end 36 and extends horizontally through the above-
ceiling space 26-as beat illustrated in FIG. 1. Spaced
apart branch supply air ducts 54 are operatively
interconnected between the bottom ofthe main supply
air duct 52 and a series of supply air diffusers 56
mounted on the underside of the ceiling 24 of the
conditioned space 22 as schematically illustrated in
FIG. 1.
When the AQMC 30 senses a need for heating or
cooling; humidification or dehumidification; and/or
removing suspended particles or other air pollutants,
the AQMC 30 will energize the appropriate components of
the unit 10 and/or the system 12. For example, if the
AQMC 30 senses a need for heating or cooling, the
blower 42 draws return air 58 upwardly into the cabinet
32, through the return air grille 50 and the return air
duct 48, and then forces the air through the unit 10,
across the heat exchanger 44 and the cooling coil 46,
and into the main supply air duct 52. The heated or
cooled air forced into the main supply air duct 52 is
discharged into the space 22, in the form of
~ ~~.'~~29~~
13
conditioned air 58a, through the branch supply ducts 54
and the ceiling mounted air diffusers 56.
The HVAC unit 10 is merely representative of a
wide variety of units, which may be generically
referred to as "air handling" units, into which the air
purification system 12 and the AQMC 30, which will be
subsequently described herein, may be operatively
incorporated. For example, while the unit 10 has been
illustratively described as being adapted to both heat
and cool the conditioned space 22, it could
alternatively be a heating-only unit, a cooling-only
unit, or simply a ventilating unit. Additionally,
while the unit 10 has been depicted in a horizontal
interior air flow orientation, it could also be
I5 alternatively oriented in a vertical air flow
orientation (of either the upflow or downflow variety).
Referring again to FIG. 2, the air purification
system 12 includes a horizontally oriented hollow
rectangular metal housing 60 representatively disposed
in an upwardly spaced apart relationship with the
return air duct 48 and a rear end portion of the unit
cabinet 32_ Housing 60 has an open inlet end 62 that
faces the exterior wall 18, and an open outlet end 64.
Operatively disposed within the housing 60 are, from
right to left as viewed in FIG. 2, upper outside air
and lower return air flow control damper sections 66
and 68 positioned at the inlet end of the housing 60; a
liquid dispersion unit 70; a liquid spray air cleaner
structure 72; a mechanical mist eliminator 74;
dehumidification cooling coils 76; and an auxiliary
supply air blower 78 disposed at the outlet end of the
housing 60. As later described herein, a liquid sump
pan structure 80 is positioned within the housing 60
beneath the air purification system components 70,72,74
14
and 76.
A discharge duct 82 is connected between the
outlet end 64 of the housing 60 and a top side portion
of the unit cabinet 32, generally between the filter 40
and the blower 42, and serves to communicate the
interiors of the housing 60 and the unit cabinet 32.
An auxiliary return duct 84 is operatively connected
between the ceiling mounted return air grille 50 and
the damper section 68, and an outside air intake duct
86 is operatively connected between the damper section
66 and an outside air intake louver 88 mounted on the
exterior wall 18.
During operation of the main unit 10, simultaneous
operation of the purification system air blower 78
draws return air 58 into the housing 60 sequentially
through the a portion of the return air grille 50, the
auxiliary return air duct 84 and the damper section 68.
At the same time, outside air 90 is also drawn into the
housing 60 sequentially through the outside air intake
louver 88, the outside air duct 86 and the damper
section 66. By the operation of the blower 78, these
incoming quantities of return air and outside air are
flowed across the purification and humidification
components 70,72,74 and 76 to form a quantity of
purified air 92 that is delivered into the unit cabinet
32 between the filter 40 and the main supply air blower
42. Together with the return air 58 entering the
cabinet 32 through the damper section 38 and the filter
40 the purified air 92 forms the conditioned air 58a
discharged from the supply air diffusers 56 (see FIG.
1) .
It should be noted that both the purified air
percentage o~ the conditioned air 58a delivered to the
space 22 served by the unit 10, as well as the outside
CA 02175294 1999-06-22
air-to-return air ratio of the purified air 92, may be
conveniently controlled by suitable adjustment of the
three damper sections 38,66 and 68 - an adjustment that
may be carried out manually or automatically depending
5 upon the degree and type of air proportioning control'
desired in conjunction with the overall operation of
the unit 10 and its associated air purification system
12. For exampl~=_, the damper sections 38 and 68 shown
in FIG. 2 may b.=_ linked in a manner such that a
10 movement of the vanes of the damper section 38 toward
their closed po;~itions correspondingly moves the vanes
of the damper section 68 toward their fully open
positions, and vice versa. This permits the regulation
of the total percentage of the discharge air 58a which
15 has traversed the purification system 12.
Further, the damper sections 66 and 68 may be
linked together in a manner such that movement of the
vanes in the damper section 68 toward their fully
closed positions automatically move the vanes in the
damper section 66 toward their fully open positions,
and vice versa. This permits the selective varying of
the outside air--to-return air ratio of the purified air
92.
Still referring to FIG. 2, the water dispersion
unit 70 is basically a pad of fibrous matting material
(such as shredde=d plastic, fiberglass or metal) similar
to the spray pad material used in evaporative coolers
and is operative: to receive a throughflow of air while
at the same time' being impinged upon by a cleansing
liquid spray. The air cleaner structure 72 is
representatively a horizontally spaced series of
vertically extending tubes 96 having discharge orifices
formed along their lengths and facing the downstream
16
side of the water dispersion unit 70. The mist
eliminator 74 representatively comprises a plurality of
vertically spaced rows of horizontally extending angled
baffle members 98 which, in a right-to-left direction
define a zigzag air flow path through the overall mist
eliminator structure.
The dehumidification cooling coils 76, which are
preferably included in the purification system 12,
representatively are direct expansion refrigerant
cooling coils the operation of which may be controlled
by the AQMC 30 which receives signals from the multi-
parameter sensing apparatus 100 that measures
temperature, humidity, suspended particles and other
air pollutants in air being discharged by the blower 42
and is operatively disposed in the main supply air
duct 52. Other dehumidification means, such as an
electrostatic precipitator, chemical dehumidifier,
centrifugal mist eliminator, mist eliminator pad or
desiccant pad or the like, may be used in place of or
in addition to the coils 76 if desired. Aa will
additionally be appreciated, the cooling medium for the
coils 76 could be one other than refrigerant (such as
chilled water) if desired.
During operation of the purification system blower
78 return air 58 and outside air 90 entering the inlet
end 62 of the system housing 60 are drawn through the
dispersion unit 70 while pressurized water 102,
supplied to the tubes 96 from a subsequently described
source, is sprayed onto the left or downstream side of
the dispersion unit 70. Particulate and chemical
pollutants in the return air/outside air mixture
passing through the dispersion unit 70, such as dust,
pollen, smoke, aerosols, ozone, nitrogen oxides, sulfur
oxides, carbon dioxides and carbon monoxides,
~~'~~29~
17
formaldehyde, fluorine, hydrogen sulfide and
hydrocarbons, are absorbed into the impinging water
spray and thus are drained with the spent water into
the sump structure 80.
The purified, now moisture-laden return
air/outside air mixture is then drawn, via the
aforementioned zigzag path, through the mist eliminator
74 which functions to mechanically remove a substantial
portion of the moisture from the return air/outside air
mixture. Water mechanically removed from the air in
this manner is drained from the mist eliminator 74 and
falls into the sump pan 80. Further moisture is
removed from the air exiting the mist eliminator 74 by
the dehumidification of the coils 76 ae automatically
called for by the AQMC 30 with measurements received
from the multi-parameter sensing apparatus 100.
Accordingly, the air 92 entering the unit cabinet 32 is
both cleansed of pollutants and dehumidified before
being mixed with the return air 58 exiting the filter
40 and delivered to the conditioned space 22.
Turning now to FIGS. 3 and 4, the sump pan 80 has
an open top side 104 and an overflow fitting 106
secured to a side wall of the sump pan, just beneath
its open top side, and connected to a suitable drain
line 108 that is tied into the building drainage
system. A quantity of water 102 is continuously
maintained in the sump pan 80, at an operating level
110, by the operation of a float-operated fill valve
112 connected to a suitable water makeup supply pipe
114. Appropriate heating and/or cooling means (not
illustrated) may be used to control the temperature of
thewater if desired.
A spray pump i16 is supported in the sump pan 80
and has an open-ended inlet pipe 118 submerged in the
18
water 1D2. The outlet of the pump 116 is connected to
the inlet of a two-way switchable diverting valve 120
by a discharge pipe 122. A pipe 124 is interconnected
between the normally closed outlet port 126 of valve
120 and an end 128 of a cylindrical, backwashable
filter structure 130, and a pipe 132 is connected
between the normally open outlet port 134 of the valve
120 and the opposite end 136 of the filter structure
130.
A supply pipe 138 has a awitchable, normally open
valve 140 therein and is connected at one end to the
end 128 of the filter structure 130 and at the opposite
end to the vertical pipes 96 of the liquid spray air
cleaner structure 72 (see FIG. 2). A discharge pipe
142 has a switchable, normally closed valve 144 therein
and is connected at one end to the end 136 of the
filter structure 130, and at its opposite end to a
drain line 146 extending from the bottom side of the
sump pan and connected to the building drainage system.
During normal operation of the purification system
12 the pump 116 forces water 102 from the sump pan 80
to the spray pipes 96 sequentially through the pipe
122, the normally open outlet 134 of the valve 12D, the
interior of the filter 13D, and the pipe 138 (as
indicated by the solid Line flow arrows in FIG. 4) to
thereby create the water spray that continuously
impinges on the downstream side of the water dispersion
unit 70 (see FIG. 2). Pollutant-bearing water also
continuously drains from the previously described air
purifying components of the system 12 back into the
sump pan 80 and is recycled through and cleansed by the
filter structure 130 on its way back to such air
purifying components.
Even with the pollutant cleansing action of the
19
filter 130, as the filter nears its fully loaded state
the levels of various contaminants in the sump water
will increase. A monitor and additive injector 148 is
disposed in the sump water 102 and is operative to
sense a decrease in the normal concentration of
chemical treatment additive in the water and/or the
buildup therein of undesirable water pollutants, such
as algae, slime, bacteria and fungi, and responsively
inject a suitable chemical additive, from an additive
container 150 connected to the monitor/injector 148,
into the sump water to control the buildup of these
water pollutants and thereby reduce their deleterious
effects on the air cleansing efficiency of the
recirculating sump water. In addition, when the AQMC
30 receives signals from the sensing apparatus 100 that
indicate the presence of difficult to remove air
pollutants, the AQMC 30 activates the monitor/injector
148 to inject a suitable chemical treatment additive
from additive container 150 into the sump water to
assist in cleaning the air. The additive in the
container 150 may representatively contain (1) selected
non-toxic organic or inorganic chemicals which assist
in cleaning the air of difficult to remove pollutants
and/or (2) non-toxic bactericides, fungicides,
herbicides and the like to control the aforementioned
water pollutants.
A monitor and filtering control structure 152 is
also disposed in the sump water 102 and is electrically
coupled to the valves 120,140 and 144 via the
schematically depicted dashed control lines in FIG. 3.
The monitor/control structure 152 is operative to sense
an increase in back pressure indicated by a pressure
transducer 154 located in pump discharge pipe 122
upstream of the filter 130 and/or the presence of a
20
predetermined maximum level of particulate and gaseous
air pollutants in the sump water 102 (which have been
withdrawn from the air flowing through the purification
system) and responsively switch the valves 120, 140 and
144 in a manner (1) opening the normally closed outlet
I26 in valve 120 and closing its normally open outlet
134, (2) closing the normally open valve 140, and (3)
opening the normally closed valve 144.
The switching of these three valves causes the
water being discharged from the pump 116 to backwash
the filter 130 by forcing sump water sequentially
through the pipe I22, the opened valve outlet 126,
through the filter 130 from top to bottom as viewed in
FIG. 4, and through the pipe 142 and the opened valve
144 into the drain pipe 146 as indicated by the dashed
line flow arrows in FIG. 4. Accordingly, the trapped
particulate matter and other pollutant matter in the
filter are flushed into the building drainage system
via the drain pipe 146. In response to the resulting
drop in the sump water level, the float-operated fill
valve 112 opens-to replenish the sump water supply with
clean water. When the particulate/gaseous pollutant
level in the sump water falls to an acceptable level,
the monitor structure 152 responsively permits the
valves 120, 140 and 144 to return to their normal
operating positions to permit the pump 116 to deliver
water to the liquid spray air cleaner structure 72
through the now backwaehed filter 130.
As can be seen from the foregoing, the
incorporation of the air purification system 12 into
the representative air handling unit 10 affords the
unit the ability to continuously flow highly purified
air into the conditioned interior building space 22
served by the unit. The cooperative use of the damper
21
structures 38,66 and 68 permits control of the overall
volumetric air cleansing rate of the purification
system 12 while at the same time permitting a
selectively variable quantity of outside ventilation
air to be introduced into the conditioned space.
Moreover, the automatic control characteristics of the
liquid spray purification system 12 substantially
reduce the amount of inspection and maintenance time
required to keep it in good working order. The unit 10
is thus quite suitable for both residential and
commercial heating, ventilating and air conditioning
applications.
The liquid spray-based air purification principles
of the present invention may also be incorporated in
other types of air handling units as illustrated by the
air purification and controlled humidification unit 160
and the AQMC 30, both schematically depicted in FIGS.
5A and 5B. The unit 160 is a free standing structure
adapted to be supported on a floor 162 6r other
horizontal support surface, and includes a vertically
elongated rectangular housing 164 having front and rear
exterior side walls 165 and 166, a top end wall 168,
opposite left and right exterior side walls 169
extending between the front and rear exterior side
walls 165 and 166, and a vertically extending interior
partition wall 170 that divides the interior of the
housing 164 into front and rear plenum areas 171a and
171b. A vertically spaced pair of air inlet grilles
172,174 are mounted on the rear housing side wall 166,
with the air inlet grille 172 being positioned adjacent
the bottom end of the housing 164, and the air inlet
grille 174 being spaced upwardly apart from the air
inlet grille 172 on a vertically intermediate portion
of the rear housing side wall 166.
22
The air inlet grille 172 is communicated with a
lower end portion of the front plenum area 171a via a
transfer duct 176 extending horizontally through the
rear plenum area 171b between the air inlet grille 172
and a suitable opening in the vertical partition wall
170. Installed in a right end portion of the transfer
duct 176 is an electrically operable, normally open
motorized air flow control damper structure 178. The
air inlet grille 174 is communicated with a vertically
intermediate portion of the front plenum area 171a via
a transfer duct 180 extending horizontally through the
rear plenum area 171b between the air inlet grille 174
and a suitable opening in the vertical partition wall
170. Installed in a-right end portion of the transfer
duct 180 is an electrically operable, normally closed
motorized air flow control damper structure 182.
Positioned immediately above the control damper
structure 182 in an opening in the partition wall 170
is an electrically operable, nox~nally closed motorized
air flow control damper structure I84 through which the
plenum areas 171a,171b are communicated.
An air discharge grille 186 is mounted on the top
end of the front side wall 165 over an electrically
operable, normally open motorized air flow control
damper structure 188 that faces and is forwardly spaced
apart from an electrically operable, normally closed
motorized air flow control damper structure 190 mounted
in an opening in the top end of the vertical partition
wall 170.
Vertically arranged in the front plenum area 171a
are air purification and controlled humidification
components similar to those incorporated in the
previously described air purification system 12
schematically depicted in FIGS. 2-4. These components,
23
which have been given reference numerals identical to
those of their counterparts in FIGS. 2-4, include, from
top to bottom in FIGS. 5A and 5B, (1) a supply air
blower 78 and dehumidification cooling coils 76
vertically positioned between the damper structures
188,190 and the damper structure 184; (2) a mechanical
mist eliminator-74, a liquid spray air cleaner
structure 72, and a liquid dispersion unit 70
vertically positioned between the damper structures
182,178; and (3) a liquid sump pan structure 80
positioned at the bo-ttom end of the front plenum area
171a.
Mounted within the sump pan structure 80 is a
schematically indicated pumping, filtering and
pollution monitoring system 192 whose components are
identical to those depicted in the previously described
FIGS. 3 and 4. The components of the system 192 are
connected to the liquid spray air clEaner structure 72
in the same manner as their counterpart components in
FIGS. 3 and 4 are connected to the liquid spray air
cleaner structure 72 in FIG. 2. During operation of
the air purification and controlled humidification unit
160, water draining from the components 70,72,74 and 76
falls into the liquid sump pan structure 80. Aa
previously described, the sensing apparatus 100
measures temperature, humidity, suspended particles and
other pollutants in the air and, in this particular
application, is mounted in an upper end portion of the
front plenum area 171a. Sensing apparatus 100 is wired
to the AQMC 30 and, ae subsequently described herein,
sends temperature, humidity and air quality
measurements to the AQMC 30 which is operatively wired
to (1) the motorized damper structures 178, 182, 184,
188 and 190, (2) the supply air blower 78, (3) the
21'~~294
24
coils 76 for dehumidification and/or cooling, (4) the
air cleaner structure 72, and (5) appropriate
components of the sump pan 80 as schematically
indicated by the dotted line electrical circuitry 196.
Referring now to FIG. SA, during normal operation
of the unit 160 the damper structures 182, 184 and 190
are fully closed, and the damper structures 178 and 188
are fully open. Operation of the supply air blower 78
draws air 198 from the conditioned space 200 served by
the unit 160 sequentially through the air inlet grille
172, the transfer duct 176, the damper structure 178,
and upwardly through the front plenum area 171a across
the vertically arranged air purification and controlled
humidification components 70-76, and then discharges
the air outwardly through the damper structure 188 and
the air discharge grille 186 into the conditioned apace
200 in the form of purified air 198a with controlled
humidity.
As schematically indicated in FIG. 5B, upon
sensing, via output signals from the sensing apparatus
100, that the humidity in the discharged air 198a is
above a predetermined set point humidity, the AQMC 30,
via the electrical circuitry 196, functions to
partially close the damper structure 178, partially
open the damper structures 182 and 184, partially close
the damper structure 188, and partially open the damper
structure 190. This repositioning of the various
damper structures by the AQMC 30, during operation of
the blower 78, reduces the flow rate of room air 198
being drawn inwardly through the air inlet grille 172
and passing upwardly through the purification and
humidification components 70-74, while at the same time
permitting a second flow of room air 198 to be drawn
inwardly through the return air grille 174 and into the
25
portion of the front plenum area 171a between the mist
eliminator 74 and the coils 76, thereby bypassing the
moisture-adding portion of the air purification and
humidification system.
These two flows of room air 198 are then drawn
upwardly through the blower 78 and discharged therefrom
into an upper end portion of the front plenum area
171a. As indicated in FIG. 5B, a first portion of this
discharged air 198 is forced outwardly through the air
discharge grille 186 as purified air 198a with
controlled humidity, and a second portion of the
discharged air 198 is sequentially flowed leftwardly
through the damper structure 190, downwardly through
the rear plenum area 171b, rightwardly through the
damper structure 184 into the space between the coil 76
and the mist eliminator. 74, and then upwardly across
the coils 76.
Accordingly, with the various damper structures in
their AQMC 30-controlled FIG. 5B positions, the
purified and controlled humidity air 198a delivered to
the conditioned space 200 by the unit 160 has a lower
moisture content than when the damper structures are in
their FIG. 5A orientation.- As can be seen from FIG.
5B, this lowered moisture content in the supply air
198a is achieved by (1) causing utilization of all the
dehumidifying coils 76 to thereby remove more water
from the air, (2) causing a portion of the room air 198
entering the unit 160 to bypass the moisture-adding
components 70 and 72, and (3) causing a portion of the
air 198 discharged by the blower 78 to be cycled back
across the dehumidifying coils 76 before being
delivered to the conditioned space 200.
The damper structures 178, 182, 184, 188 and 190
may be moved by action of the AQMC 30 only between
~i
26
their two indicated positions shown in FIGS. 5A and 5B.
Alternatively, the damper structures may be moved to
further positions by the AQMC 30 to provide, as needed,
for even greater moisture reduction in the air 198a
delivered to the conditioned apace 200. For example,
the AQMC 30, after the damper structures were moved to
their FIG. 5B positions, could be used to further open
the damper structures 182, 184 and 190, and further
close the damper structures 178 and 188 if movement of
the damper structures to their initial FIG. 5B
positions did not eliminate excessive moisture in the
air 198a delivered to the conditioned space 200. This
further repositioning of the damper structures would
reduce the air flow across the humidifying components
and at the same time increase the air flow bypassing
the humidifying components and operatively traversing
the dehumidifying cooling coils 76. While the air
handling unit 160 has been representatively illustrated
as being in a vertical, free standing orientation, it
will be readily appreciated by those of skill in this
particular art that it could alternatively be arranged
in a horizontal orientation as well if desired.
Illustrated in FIG. 6 is an alternate embodiment
l0a of the HVAC unit 10 previously described in
conjunction with FIGS. 1-4. I3VAC unit 10a incorporates
therein the same components as the unit 10, and
additionally incorporates a modified air purification
and controlled humidification unit 160a having therein
various indicated components of the air purification
and controlled humidification unit 160 previously
described in conjunction with FIGS.-5A and 5B. For
ease in comparing the HVAC unit l0a to the previously
described unite 10 and 160, components and structures
in the modified unit l0a similar to those in the
~~~5294
27
previously described units 10 and 160 have been given
identical reference numerals.
The HVAC unit l0a shown in FIG. 6 is provided with
a modified purification system housing 60a which,
relative to the housing 60 described in FIG. 1, is
horizontally lengthened, and is positioned closely
adjacent the top side of the cabinet 32. The modified
housing 60a has a left end wall 168 corresponding to
the top end wall 168 of the unit 160, a top aide wall
170 corresponding to the partition wall 170 in the unit
160, and a bottom side wall 165 corresponding to the
side wall 165 in the unit 160. An auxiliary housing
202 is positioned over the top side 170 of the modified
housing 60a and has a top side wall 166 corresponding
to the side wall 166 in the unit 160. The interiors
171a,171b of the housings 60a,202 respectively
correspond to the plenum areas 171a,171b in the housing
portion 164 of the unit 160 shown in FIGS. SA and 5B.
The air purification and humidification components
70,72,74,76 and 78 are positioned as shown within the
modified housing 60a, with the components 74 and 76
being horizontally separated from one another a
substantially greater distance than their counterpart
components in the IiVAC unit 10. The interior 171a of
the housing 60a; downstream of the fan 78, is
communicated with the interior of the cabinet 32,
between the filter 40 and the fan 42, by the normally
open damper structure 188 which is positioned directly
beneath the normally closed damper structure 190
mounted in the housing wall 170. Damper structures
182,184 are mounted in the housing wall 170 between the
coils 76 and the mist eliminator 74, and the sump pan
structure 80 extends beneath the components 70,72,74
and 76. Operatively mounted in the sump pan structure
28
is the pumping, filtering and monitoring system having
components identical to those shown in FIGS. 3 and 4.
A drain pan 81 is positioned beneath the main
cooling coil 46, to catch condensate dripping therefrom
during operation of the IiVAC unit 10a, and a condensate
drain line 204 having a condensate pump 206 installed .
therein is interconnected between the drain pan 81 and
the sump pan structure 80. During operation of the
HVAC unit 10a, condensate received in the drain pan 81
is transferred into the sump pan structure 80, via the
line 204, by the pump 206. The transfer duct 180
extends through the housing 202, is connected at one
end thereof to the damper structure 182, and is
connected at its other end to the auxiliary return air
duct 84 ae indicated. Via the schematically depicted
control circuitry 196, the AQMC 30 is operatively
connected to the system components indicated in FIG. 6.
During normal operation of the HVAC unit 10a, as
illustrated in FIG. 6, the damper structures 182,184
and 190 are fully closed-and-the damper structures
66,68 and 188 are fully open, and the HVAC unit 10a
operates in essentially the same manner as the
previously described HVAC unit 10. Specifically, the
purification system blower 78 draws return air 58 and
outside air 90 through damper structures 68 and 66,
respectively, into the plenum 171a. These two air
streams are mixed ae they are drawn through the
dispersion unit 70 and pressurized water 102 from the
liquid spray air cleaner structure 72, and then through
the mist eliminator 74 and dehumidification cooling
coils 76. Excess water from components 70,72,74 and 76
flows by gravity into the sump pan structure 80
positioned below such components. As the air flows
through the housing 60a, it is washed by water, excess
29
water is removed, and humidity is reduced to form
purified air 92 with controlled humidity. Then such
air 92 passes through damper structure 188 into the
unit cabinet 32 of the FIVAC unit l0a where it mixes
with return air 58 which has entered cabinet 32 through
the damper structure 38 and the filter 40.
Further humidity control is provided to the air
mixture 92/58 as it flows through (1) the heat
exchanger 44 when the unit l0a is operating in the
winter and (2) the cooling coils 46 when the unit l0a
is operating in the summer. Water removed from the air
mixture 92/58 by the cooling coiis 46 drips into the
drain pan 81. As previously mentioned, this water is
pumped frcm drain pan 81 tothe liquid sump pan
structure 80. The pumping, filtering and pollution
monitoring system within the sump pan structure 80
returns the water for recycling through the liquid
spray air cleaner structure 72.
The humidity of the resulting conditioned air 58a
is measured by the sensing apparatus 100 which also
measures temperature, suspended particles and other
pollutants in the air and transmits such measurements
to the AQMC 30. In the event the humidity of the
conditioned air 58a is below a predetermined set point
humidity (i.e., humidity needs to be increased), the
AQMC 30, via the electrical circuitry 196,
automatically calls for (1) a reduction in
dehumidification by coils 76 and/or (2) an increase in
return air 58 and/or outside air 90 flowing through
unit 160a by partially opening damper structures 68 and
66 as well as a corresponding reduction in return air
58 entering cabinet 32 by partially closing damper
structure 38.
If the humidity of the conditioned air 58a is
30
above a predetermined set point humidity, the AQMC 30
automatically calls for (1) an increase in the
dehumidification by coils 76 and/or (2) a reduction in
return air 58 and/or outside air 90 flowing through
housing 60a by partially closing damper structures 68
and 66 as well as a corresponding increase in return
air 58 entering cabinet 32 by partially opening damper
structure 38. In the event the humidity of conditioned
air 58a is still above a predetermined set point
humidity, the AQMC 30 functions to partially close
damper structures 66 and 68, partially open damper
structures 182 and 184, partially close damper
structure 188, and partially open damper structure 190.
Lower moisture content in the purified air 92 with
controlled humidity is achieved by (1) causing
utilization of all dehumidifying coils 76 to thereby
remove more water from the air, (2) changing the ratio
of purified 92 to the return air 58, (3) causing a
portion of the room air 58 entering the housing 60a to
bypass the moisture-adding components 70 and 72, and
(4) causing a portion of the air 92 discharged by the
blower 78 to be cycled back across the dehumidifying
coils 76 before being delivered to the cabinet 32.
In a manner similar to the example just described
for increasing or decreasing the humidity of the
conditioned air 58a, the AQMC 30 automatically calls
for operation of the appropriate components of the HVAC
units 10 and l0a and the air purification and
controlled humidification systems 12, 160, and 160a as
needed to sufficiently change the temperature,
suspended particles, and other air pollutants and
thereby achieve the temperature and air quality ranges
preset by the user on the AQMC 30.
FIG. 7 illustrates the Air Quality Monitor and
~~7~~~~
31
Controller (AQMC) 30. The AQMC 30 is an integral part
of the HVAC units 10 and l0a and air purification and
controlled humidification systems 12, 160, and 160a as
it automatically monitors these units and systems and
controls their operation to achieve the ranges of
temperature, humidity and air quality desired by the
user. In general, the AQMC 30 provides (1) means for
the user to preset the_desired ranges of temperature,
humidity, suspended particles and other pollutants in
the conditioned air (58a in FIGS. 1, 2, and 6 and 198a
in FIGS. 5A and 5B); (2) means for automatically
monitoring the conditioned air (SSa in FIGS. 1, 2, and
6 and I98a in FIGS. 5A and SB) to determine if such
ranges are achieved and maintained; (3) means for
automatically activating the operation of the
appropriate components of the units 10 and l0a and/or
systems 12, 160, and 160a as necessary to achieve the
temperature, humidity and air quality ranges preset by
the user on the AQMC 30; and (4) means for achieving
substantial savings in electrical energy costs by
continually monitoring the conditioned air (58a in
FIGS. 1, 2, and 6 and 198a in FIGS. 5A and 5B) via the
multi-parameter sensing apparatus IOD (see FIGS. 2, 5A,
5B, and 6) and operating only those components in such
units and/or systems that are actually necessary to
achieve the preset ranges of temperature, humidity and
air quality. When such ranges are achieved, the AQMC
stops the operation of unnecessary components.
FIG. 7 illustrates several features of the AQMC
30 30. Normally the AQMC 30 is mounted on a wall similar
to the location of a conventional thermostat. However,
the AQMC 30 may be located anyplace that is convenient
to the user provided that it is electrically coupled,
as is illustrated by the schematic lines 196 and 197 in
~1~529~
32
FIGS. 2, SA, 5B and 6, to (1) sensing apparatus I00
that measures temperature, humidity, suspended
particles and other pollutants in the conditioned air
which are monitored by the AQMC 30 and (2) the various
components of units 10 and l0a and systems 12, 160, and
160a which are controlled and operated by the AQMC 30.
The AQMC 30 includes a small, subsequently
described computer (not illustrated in FIG. 7)
operatively associated with a display screen 210 upon
which various information and measurements from such
computer are displayed. The column 214 showing
"Temperature, Humidity, Particles (TSP), Carbon
Monoxide... Other" is a listing of items to be monitored
and controlled by the AQMC 30; it should be noted that
these items are shown for purposes of illustration only
and that many other air pollutants (such as
formaldehyde, hydrocarbons, fluorine, and hydrogen
sulfide) and air quality parameters could be included.
The "Actual" column 216 shows representative actual
measurements of Temperature at 73° F, Humidity at 53~,
Particles (Total Suspended Particles, "TSP") at 0.008
mg/m3, Carbon Monoxide at 0.02 PPM, etc. As previously
indicated, the AQMC 30 may be set to operate units 10
and 10a and systems 12, 160 and 160a based on
measurements of temperature, humidity, suspended
particles, and/or other pollutants of either (1) air as
it is being discharged from such units or systems, or
(2) air at room conditions external to such units or
systems.
In addition to temperature, humidity and suspended
particles, the AQMC 30 receives measurements from
sensing apparatus 100 of the presence and concentration
of various selected gaseous pollutants that are
hazardous or harmful to the health of the occupants of
~~~~2~4
33
any indoor area such as residences, offices, factories,
chemical plants, hospitals, schools, subways, etc. as
well as of transportation vehicles such as automobiles,
trucks, trains, airplanes, etc. Although many of these
S gaseous pollutants are shown for illustration purposes
in column 214 of FIG. 7, the user or manufacturer may
elect to simplify the readout by having the screen 210
display (1) temperature and humidity only, (2)
temperature, humidity, and suspended particles only,
(3) temperature, humidity, suspended particles and one
or more selected gaseous pollutants, or (4)
temperature, humidity, suspended particles and only
those gaseous pollutants, if any, that are outside of
the Range Desired column 218. In other words,
regardless of what the user or manufacturer elects to
have displayed on the screen 210, the AQMC 30 monitors
the measurements of temperature, humidity, suspended
particles, and all gaseous pollutants and controls the
operation of the appropriate components of units 10 and
l0a and systems 12, 160, and 160a to maintain such
measurements within ranges preset in the AQMC 30. It
is envisioned
~~ r~zs~
34
that the manufacturer will determine the specific
gaseous pollutants that are to be measured and
monitored as these. may vary by area and application;
therefore, the AQMC 30 with sensing apparatus 100 may
be set for some applications to detect, measure and
monitor a limited number of specific gaseous pollutants
whereas in other applications the AQMC 30 and sensing
apparatus 100 may be set to measure a much broader
range of gaseous pollutants.
Also in FIG. 7, the "Range Desired" column 218
shows the ranges selected by the user which for
illustratian purposes are Temperature: 72-74° F;
Humidity: 40-60~; Particles (TSP): 0-0.02 mg/m'; Carbon
Monoxide: 0-1 PPM; Carbon Dioxide: 0-500 PPM; etc. It
is envisioned that the manufacturer would select
reasonable ranges for column 218; such ranges could be
changed to those desired by the user but could also be
restored to the original manufacturer's ranges by the
user as a "default" setting.
The "Range Adjustment" (RA) column 212 includes
Lower RA column 211 with (1) keys 211a to raise the
lower setting ofthe Range Desired column 218 and (2)
keys 211b to reduce the lower setting of column 218.
Also, the RA column 212 includes Upper RA column 213
with {1) keys 213a to raise the upper setting of the
Range Desired column 218 and (2) keys 213b to reduce
the upper setting of column 218. For example, to
change the Temperature Range Desired column 218 from
72-74° F to 70-75° F, the user would push (1) the
temperature key 211b two times to change the lower
setting from 72° F to 70° F and (2) the temperature key
213a one time to change the upper setting from 74° F to
75° F.
The "Alarm" column 220 includes an Alarm Setting
35
column 222 that shows the setting at which the AQMC 30
would activate an alarm to (1) alert the user of a
system malfunction or emergency condition, (2) alert an
off-site security monitoring firm to ensure that
corrective action is taken to eliminate such dangerous
condition (if so desired by the user), and (3) turn off
the system if such condition is not corrected within a
preset time period. For example, if the Actual
Temperature reading in column 216 reached or exceeded
the 100° F setting in column 222, an alarm would be
activated.
Also, the "Alarm" column 220 includes an Alarm
Adjustment column 224 with (1) keys 224a to raise the
Alarm setting column 222 and (2) keys 224b to lower the
Alarm setting column 222. For example, to lower the
Temperature Alarm Setting column 222 from I00° F to 90°
F, the user would push the temperature key 224b ten
times. As mentioned for the Range Desired column 218,
it is also envisioned that the manufacturer would
select reasonable Alarm settings for column 222; such
settings could be changed to those desired by the user
but could also be restored by the user to the original
manufacturer's settings as a default setting.
The AQMC 30 includes an Alarm control 226 with an
"On" switch 226a to allow the user to arm the alarm and
an "Off" switch 226b to allow the user to (1) disarm
the alarm or (2) turn off the alarm after it has been
activated by the AQMC 30.
The AQMC 30 also includes a Screen control 228
with an "On" switch 228a to allow the user to turn on
the screen and an "Off" switch 228b for turning off the
screen. To conserve electricity and screen life, the
screen 210 can be set to automatically turn off after
displaying its measurements and other information for a
i
~~~~z~4
36
reasonable time such as one minute. The screen 210 is
simply a means of displaying information from the AQMC
30. The screen 210 does not affect the operation of
the AQMC 30, units 10 and 10a, or systems 12, 160 and
160a, all of which continue to function whether the
screen 210 is on or off. In addition, the screen 210
can be lighted for use in the dark or its information
and measurements can be displayed with lighted letters
and numbers similar to those used on a digital clock.
As mentioned previously, the AQMC 30 can be set to
operate the HVAC units 10 and IOa and Air Purification
and Controlled Humidification systems 12, 160 and 160a
based on measurements of temperature, humidity,
suspended particles, and gaseous pollutants as follows:
Condition A - measurement of the air at room conditions
at the location of the AQMC 30 (using sensors similar
to those in the apparatus 100 but positioned outside
the particular air handling unit within the conditioned
space) or Condition B - measurement of the conditioned
air as it is being discharged from the units 10 and
10a. For example, to change the basis for such
operation for temperature and humidity from Condition A
to Condition B, the user simultaneously pushes all four
RA temperature keys (211a, 211b, 213a, and 213b) and
then simultaneously pushes all four RA humidity keys
(211a, 211b, 213a, and 213b). The AQMC 30 will then
change the temperature/humidity basis for operation of
units 1D and 10a and systems 12, 160, and 160a from
Condition A to Condition B. The user can change the
basis for such operation back to Condition A by again
simultaneously pushing all four RA temperature keys and
then simultaneously pushing all four RA humidity keys.
As will be appreciated, the principles of the
liquid spray-based air purification with the AQMC
37
30/apparatus 100 measurement, monitoring and control
system may also be incorporated in other applications.
For example, by eliminating the need to monitor and
control the air temperature and humidity, air
purification may be provided for outside applications.
Such an outside system would incorporate (1) means to
purify the air, (2) means to measure and monitor the
suspended particles and other pollutants in the clean
air, and (3) means to control the operation of the air
purification system. It can be readily appreciated by
those of skill in this particular art that the various
air purification, monitoring, and control components
illustrated in FIG. 2 may be combined to effectively
and economically clean the air for outdoor
applications. Referring to FIG. 2, such an outdoor
system would incorporate (1) a housing 60 with an open
inlet end 62 and open outlet end 64, (2) a liquid
dispersion unit 70, (3) a liquid spray air cleaner
structure 72, (4) a mechanical mist eliminator 74, (5)
a liquid sump pan 80 (as shown with more detail in
FIGS. 3 and 4), (6) an air supply blower 78 disposed
near the outlet end of the housing 60, (7) an apparatus
100 that measures suspended particles and gaseous
pollutants in the air and which is disposed downstream
of the air blower 78 at the outlet end of the housing
60, and (8) an AQMC 30. Such AQMC 30 is electrically
coupled (1) to the apparatus 100 that sends
measurements of suspended particles and gaseous
pollutants to the AQMC 30 and (2) to the various
components 72, 78 and 80 the operation of which are
controlled by the AQMC 30. Outside applications
include smoke stacks, chemical plants, parking garages,
freeway toll booths, industrial areas, and other areas
that have outdoor air pollution problems. It will also
21~~~9~
38
be appreciated that some applications may simply
require the AQMC 30/apparatus 100 to measure and
monitor compliance with existing clean air guidelines.
Turning now to the schematic block diagram of FIG.
8, the AQMC 30 incorporates therein a small computer
230 with suitable processor and preprogrammed memory
portions 232 and 23~. The mufti-parameter sensing
apparatus 100 has operatively associated therewith a
series of sensors S1-S9 that respectively sense, via
the schematically depicted parameter sensing lead lines
236a-236i, the temperature, humidity, and levels of
suspended particles, carbon monoxide, carbon dioxide,
ozone, sulfur dioxide, nitrogen dioxide, and other
pollutants in the space being monitored. The monitored
space, as previously mentioned, may be in the air
discharge of the particular air handling unit with
which the AQMC 30 is associated, or outside of the air
handling unit in the conditioned space.
Upon sensing the predetermined environmental
parameters, the sensors S1-S9 responsively and
respectively output to the computer 230 the indicated
sensed parameter signals SP1-SP9. In turn, the
computer 230 responsively outputs the panel control
signals PC1-PC9 and the system control signals SC1-SC9.
The signals PC1-PC9 are utilized to control the various
previously described illuminated displays on the
control panel 210 (see FIG. 7y, while the system
control signals SC1-SC9 are routed to appropriate
components in the particular air handling unit and its
associated air purification system.
Using the unit 10 and its associated air
purification system 12 shown in FIG. 2 as an example,
the output signal SC1 is a sensed temperature signal
and is routed to the HVAC unit 10 in the same manner as
~f ~~2~~
39
a conventional thermostat signal; output signal SC2 is
a sensed humidity signal and is routed to the
dehumidification coils 76 and the damper structures
38,66,68 as would the output signal of a conventional
humidistat; and the output signals SC3-SC9 are sensed
pollution level signals which are transmitted to the
air purification system 12 and respectively correspond
to the sensed pollution levels of particulate matter,
carbon monoxide, carbon dioxide, ozone, sulfur dioxide,
nitrogen dioxide and selected "other" pollutants as
indicated on the face of the control panel 210 (see
FIG. 7). As will be readily appreciated, the sensed
parameter signals SP1-SP9 combinatively form the dashed
line output signal 197 (FIGS. 2, 3; 5A, 5B and 6) from
the multi-parameter sensing apparatus 100, while the
system control output signals SC1-SC9 combinatively
form the dashed line output signal 196 from the AQMC 30
to the particular air handling unit and its associated
air purification system (FIGS. 2, 3, 5A, 5B and 6).
Turning now to the schematic flow diagram in FIG.
9, the monitoring and control operation of the computer
230 in generating the corrective system control signals
SC1-SC9 will be briefly described. Basically, the
computer 230 in the AQMC 30 continuously "polls" the
various sensed parameters in a sequential fashion and
responsively generates the corrective system control
signals SC1-SC9 as needed to maintain the parameters
within their predetermined ranges.
As schematically indicated by the input line 238
the computer 230 receives all of the sensed parameter
signals SP1-SP9 from the parameter sensing apparatus
100 and, in step 240, also receives the user or
manufacturer-established desired ranges and alarm
values for all of the sensed parameters. At step 242
~~I~2~4
the computer then selects a first one of the inputted
parameters and, in the next step 244, determines
whether the selected parameter is within its desired
range. If it is, the computer (at step 246) determines
5 whether the associated corrective signal (SC) is being
generated. If it is, the computer, at step 248, turns
off the corrective signal and continues to step 250 in
which the computer determines whether all of the
parameters have been checked. If they have not, the
10 computer executes the indexing step 252, selects the
next parameter and returns to step 244. If all
parameters have been checked, the computer starts the
parameter polling process again, returning to step 242
as indicated.
15 Returning to step 244, if the computer determines
in this step that the sensed value of the selected
parameter is not within the selected range it executes
step 254 and determines whether the sensed parameter
value is at its predetermined alarm level. If it is,
20 the alarm is issued via step 256 and, at step 258, the
computer queries whether the corrective signal is being
generated. If the corrective signal is not being
generated, the computer generates it via step 260 and
returns to step 250. If the corrective signal is being
25 generated, the computer bypasses step 260 and returns
directly to step 250 as indicated. In the foregoing
manner, the computer 230 continuously monitors and
adjusts the air handling unit and associated air
purification system to which the AQMC 30 and multi-
30 parameter sensing apparatus 100 are operatively
coupled.
41
The foregoing detailed description is to be
clearly understood as being given by way of
illustration and example only, the spirit and scope of
the present invention being limited solely by the
appended claims.
