Method and system for conditioning air in an enclosed environment with distributed air circulation systems

Abstract

A system for conditioning air in a building including a fan-coil unit arranged adjacent to or within an indoor space within the building and additionally configured to at least one of heat and cool the air of the indoor space, and a scrubber arranged adjacent to or within the indoor space, the scrubber configured during a scrub cycle for scrubbing of indoor air from the indoor space. The scrubber includes one or more adsorbent materials arranged therein to adsorb at least one predetermined gas from the indoor air during the scrub cycle, and an exhaust, wherein the scrubber is configured during a purge cycle to direct a purging air over and/or through the adsorbent materials to purge at least a portion of the at least one predetermined gas adsorbed by the adsorbent materials during the scrub cycle from the adsorbent materials and thereafter exhausting the flow via the exhaust.

Claims

1. A system for conditioning air in a building, comprising: a fan-coil unit arranged adjacent to or within an indoor space within the building and additionally configured to at least one of heat and cool the air of the indoor space; and a scrubber arranged adjacent to or within the indoor space, the scrubber configured during a scrub cycle to scrub indoor air from the indoor space, the scrubber including: one or more adsorbent materials arranged therein to adsorb at least one gas from the indoor air during the scrub cycle; and a source of purging gas, wherein the scrubber is configured, during a purge cycle, to direct the purging gas over and/or through the one or more adsorbent materials to purge at least a portion of the at least one gas adsorbed by the one or more adsorbent materials during the scrub cycle from the one or more adsorbent materials and thereafter exhaust the purging gas via an exhaust.

2. The system of claim 1, wherein the purging gas includes indoor air from the indoor space.

3. The system of claim 1, wherein flow of indoor air from the indoor space to the scrubber or from the scrubber to the indoor space is ductless.

4. The system of claim 1, wherein the at least one of heating and cooling the air of the indoor space is performed without introducing outdoor air into the indoor space.

5. The system of claim 1, where the at least one gas includes one or more of carbon dioxide, volatile organic compounds, sulfur oxides, radon, nitrous oxides and carbon monoxide.

6. The system of claim 1, wherein the one or more adsorbent materials includes one or more of granular adsorbent particles, solid supported amines, activated carbon, clay, carbon fibers, carbon cloth, silica, alumina, zeolite, synthetic zeolite, hydrophobic zeolite, natural zeolite, molecular sieves, titanium oxide, polymers, porous polymers, polymer fibers and metal organic frameworks.

7. The system of claim 1, wherein the one or more adsorbent materials are contained in one or more removable cartridges.

8. An air treatment system for conditioning air in a building, comprising: a fan-coil unit configured to circulate indoor air of an indoor space; heating or cooling means configured to respectively heat or cool the indoor air; a scrubber configured, during a scrub cycle, to scrub the indoor air from the indoor space, the scrubber placed within or adjacent to the indoor space and including one or more adsorbent materials arranged therein to adsorb at least one gas from the air of the indoor space during the scrub cycle, and a source of purging gas; wherein, during a purge cycle, the scrubber is configured to flow the purging gas over and/or through the one or more adsorbent materials to purge the one or more adsorbent materials of at least a portion of the at least one gas adsorbed by the one or more adsorbent materials and thereafter exhaust the purging gas via an exhaust.

9. The system of claim 8, wherein the purging gas includes indoor air from the indoor space.

10. The system of claim 8, wherein flow of indoor air from the indoor space to the scrubber or from the scrubber to the indoor space is ductless.

11. The system of claim 8, where the at least one gas includes one or more of carbon dioxide, volatile organic compounds, sulfur oxides, radon, nitrous oxides and carbon monoxide.

12. A method for conditioning air in a building, comprising: circulating indoor air of an indoor space via a fan-coil unit; scrubbing the indoor air during a scrub cycle using a scrubber placed within or adjacent to the indoor space, the scrubber including one or more adsorbent materials arranged therein to adsorb at least one gas from the air of the indoor space during the scrub cycle; flowing a purging gas over and/or through the one or more adsorbent materials so as to purge the adsorbent materials of at least a portion of the at least one gas adsorbed by the one or more adsorbent materials; and thereafter exhausting the purging gas flow via an exhaust.

13. The method of claim 12, wherein the purging gas includes indoor air from the indoor space.

14. The method of claim 12, wherein the fan-coil unit is supplied refrigerant or heating fluid from a variable refrigerant flow (VRF) system.

15. The method of claim 12, wherein the fan-coil unit is supplied chilled or heated water from a central chiller or boiler.

16. The method of claim 12, wherein the scrubber further comprises at least one of a damper and a fan, the method further comprising switching the scrubber from the scrub cycle to the purge cycle using the at least one of the fan and the damper.

17. The method of claim 16, further comprising performing the switching according to at least one of: a preset schedule, a predetermined level of the at least one gas, the indoor space occupancy level, a manual trigger, a signaled command and an externally signaled command.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The principles and operations of the systems, apparatuses and methods according to some embodiments of the present disclosure may be better understood with reference to the drawings, and the following description. These drawings are given for illustrative purposes only and are not meant to be limiting.

(2) FIG. 1 is a simplified schematic illustration of a system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(3) FIG. 2 is a simplified schematic illustration of another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(4) FIG. 3 is a simplified schematic illustration of yet another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(5) FIG. 4 is a simplified schematic illustration of still another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(6) FIG. 5 is a simplified schematic illustration of another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(7) FIG. 6 is a simplified schematic illustration of yet another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(8) FIG. 7 is a simplified schematic illustration of still another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(9) FIG. 8 is a simplified schematic illustration of yet another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(10) FIGS. 9A-9E are each a simplified schematic illustration of still another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure;

(11) FIGS. 10A and 10B are each a simplified schematic illustration of another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure; and

(12) FIGS. 11A-11D are each a simplified schematic illustration of another system for conditioning air in an enclosed environment according to some embodiments of the present disclosure.

DETAILED DESCRIPTION

(13) FIG. 1 is a simplified schematic illustration of a system 100 for conditioning air in an enclosed environment 102 (e.g., the interior of a building) according to some embodiments of the present disclosure. FIG. 2 is another simplified schematic illustration of a system 104 for conditioning air in the enclosed environment 102 according to some embodiments of the present disclosure, and FIG. 3 is yet another simplified schematic illustration of a system 106 for conditioning air in the enclosed environment 102 according to some embodiments of the present disclosure. As seen in FIGS. 1-3, the respective systems 100, 104 and 106 for conditioning air in the enclosed environment 102 each comprise a distributed air circulation system 110.

(14) The enclosed environment 102 may comprise an office building, a commercial building, a bank, a residential building, a house, a school, a factory, a hospital, a store, a mall, an indoor entertainment venue, a storage facility, a laboratory, a vehicle, an aircraft, a ship, a bus, a theatre, a partially and/or fully enclosed arena, an education facility, a library and/or other partially and/or fully enclosed structure and/or facility which can be at times occupied by equipment, materials, live occupants (e.g., humans, animals, synthetic organisms, etc.) and/or any combination thereof.

(15) According to some embodiments, the enclosed environment 102 may comprise a plurality of indoor spaces 120, such as rooms, cubicles, zones in a building, compartments, railroad cars, caravans or trailers, for example. Adjacent to the indoor space 120 may be an air plenum 124, typically located above the ceiling of the indoor space 120. As seen in FIG. 1, each indoor space 120 is associated with a separate air plenum 124, though a common air plenum 124 may be associated with a plurality of indoor spaces 120.

(16) According to another embodiment, the enclosed environment 102 may comprise a single indoor space 120. An exemplary enclosed environment 102 comprising a single indoor space 120 will be further described in reference to FIG. 7.

(17) The distributed air circulation system 110 conveys chilled or heated fluid to local air circulation units 126. Typically, nearly each indoor space 120 is associated with a local air circulation unit 126, which circulates and cools or heats the indoor air of the indoor space 120. As seen in FIGS. 1 and 3, each indoor space 120 is associated with an air circulation unit 126. In FIG. 2 only the left side indoor space 120 is associated with an air circulation unit 126.

(18) In the embodiments shown in FIGS. 1-11C the air circulation unit 126 comprises a fan-coil unit 128. It is appreciated that the air circulation unit 126 may comprise any other suitable device for circulating and cooling or heating air in indoor spaces 120, such as a blower-coil unit, for example. In some embodiments the air circulation unit 126 may be a component in a split unit system.

(19) The chilled or heated fluid may originate from a centralized chilling or heating system shared by a plurality of air circulation units, or from a single dedicated heat pump or boiler (not shown). In accordance with some embodiments, the fluid may be supplied by a Variable Refrigerant Flow (VRF) system. In accordance with another embodiment the fluid may be supplied by a Fixed Refrigerant Flow system or by a direct expansion (DX) system. In other distributed air circulation systems the fluid may be water.

(20) The fan-coil unit 128 may comprise a housing 130 including a fan 134 and coils 136. The coils 136 are typically cooled or heated by the fluid. The coils 136 may comprise a cooling coil 138 and/or a heating coil 140 and/or any other suitable cooling or heating means, such as radiators, electrical heaters, chillers, heat exchangers, nozzles or jets, for example.

(21) At least a portion of the indoor air may exit the indoor space 120 as return air 150. In accordance with some embodiments, the return air may enter the air plenum 124. Typically the return air 150 enters the air plenum 124 without flowing through a duct, though in some embodiments a duct (not shown) may be provided.

(22) In accordance with other embodiments the indoor space 120 may be associated with an adjacent area above its ceiling instead of the air plenum 124. The return air 150 may flow within a duct (not shown) located in the area above the ceiling to the fan-coil unit 128.

(23) The fan 134 draws the return air 150 to enter fan-coil unit 128, via an entry port 154, and flow in the vicinity of coils 136 for heating or cooling thereof. In FIGS. 1-3 the coils 136 are placed downstream the fan 134. Alternatively, the coils 136 may be placed intermediate the fan 134 and the entry port 154 or at any other suitable location. Return air 150 may flow through a particle filter 158 for removing dust and airborne particles therefrom.

(24) Conditioned air 160, i.e. return air cooled or heated by the coils 136, exits via an exit port 164. The conditioned air 160 enters the indoor space 120 for circulation thereof. The conditioned air 160 may flow from the fan-coil unit 128 into the indoor space via a duct 168 or may ductlessly flow into the indoor space 120.

(25) A portion of the indoor air may be exhausted from the enclosed environment 102 as exhaust air 170 into the ambient or any location outside the enclosed environment 102. Any suitable means, such as a blower or a fan (not shown) may be used to exhaust the exhaust air 170. The exhaust air 170 may exit the indoor space 120, via an exhaust port 172, and/or may exit the air plenum 124, via an exhaust port 176 or via an exhaust port (not shown) of the fan-coil unit 128.

(26) In standard distributed air circulation systems fresh, outdoor air or namely makeup air 180 may be introduced into the enclosed environment 102 for supplying nominally fresh, good quality air combining with the return air 150. The outdoor air 180 may be introduced into the enclosed environment in any suitable manner, such as by a network of ducts 184. In the embodiment shown in FIGS. 1 and 3 the outdoor air 180 may be introduced directly into each of the indoor spaces 120, via an entry port 188, or the outdoor air 180 may be introduced into the air plenum 124, via an entry port 190. In another embodiment, the outdoor air 180 may be introduced directly into each fan-coil unit 128, as shown in FIG. 2. As seen in FIG. 2, the duct 184 is directed to introduce the outdoor air 180 into the fan-coil unit 128 prior to the particle filter 158, though the outdoor air 180 may be introduced into the fan-coil unit 128 at any suitable location therein.

(27) A scrubber 200 is provided to reduce the concentration of contaminants present in the return air 150 flowing therein. A contaminant may be a predetermined gas or vapor, such as CO.sub.2, for example. The scrubber 200 may comprise a CO.sub.2 scrubber 204. Examples of CO.sub.2 scrubbers are disclosed in applicant's U.S. Pat. No. 8,157,892, which is incorporated herein by reference in its entirety. The CO.sub.2 scrubber 204 may comprise any suitable material for capturing CO.sub.2, such as a CO.sub.2 adsorbent material. An exemplary CO.sub.2 adsorbent material may be a solid support material supporting an amine-based compound, such as disclosed in applicant's PCT application PCT/US12/38343, which is incorporated herein by reference in its entirety. Other adsorbent materials include, but are not limited to, granular adsorbent particles, clay-based adsorbents, activated carbon, zeolites, natural zeolite, activated charcoal, molecular sieves, silica, silica gel, porous silica, alumina, porous alumina, titanium oxide, carbon fibers, porous polymers, polymer fibers and metal organic frameworks.

(28) The CO.sub.2 scrubber 204 may include a plurality of CO.sub.2 scrubbing cartridges 210. The CO.sub.2 scrubbing cartridges 210 may comprise the adsorbent material formed as a solid or flexible sheet or as granules supported by porous surfaces. The scrubbing cartridges 210 may be arranged in any suitable arrangement. For example, the CO.sub.2 scrubbing cartridges 210 may be parallelly arranged therebetween. Alternatively, as seen in FIG. 1, the CO.sub.2 scrubbing cartridges 210 may be staggeringly arranged therebetween. This staggered arrangement allows substantially parallel air flow paths of the return air 150 therethrough. Exemplary CO.sub.2 scrubbing cartridges and modules are disclosed in applicant's US Patent Publication No. 20110198055, which is incorporated herein by reference in its entirety.

(29) An additional contaminant may be VOCs. The scrubber 200 may comprise a VOC scrubber 214 for removing VOCs from the return air 150 flowing therethrough. The VOC scrubber 214 may comprise any suitable adsorbent material for adsorbing the VOCs. For example VOC adsorbent materials may comprise a hydrophobic zeolite, natural zeolite, synthetic zeolite, carbon cloth, activated carbon, a molecular sieve, polymers, a thin permeable sheet structure, carbon fibers, or granular adsorbent particles attached to a sheet of some other permeable material, such as paper, cloth or fine mesh, for example.

(30) The VOC scrubber 214 may be arranged in any suitable arrangement, such as a bed of granular material, a flat sheet, or a pleated sheet, as shown in FIG. 1.

(31) A filter 216 may be provided for removing additional contaminants, such as dirt, small airborne particles and may comprise any suitable filter or adsorbent material.

(32) Operation of the scrubber 200 may comprise a scrub cycle and a purge cycle. During the scrub cycle, the contaminants are captured and adsorbed by the adsorbent material or any other means. A portion of the return air 150 may be urged by a scrubber fan 224 to flow into the scrubber 200. The return air 150 may flow into the scrubber 200 via an entry port 226 including an entry damper 228, when positioned in an open state.

(33) The volume of the portion of the return air 150 flowing into the scrubber 200 may be controlled by the scrubber fan 224 and/or damper 228, or by any other suitable means. In some embodiments, a volume of approximately 1%-50% of the fan-coil airflow (namely air flowing through the fan-coil unit 128) may enter the scrubber 200. In some embodiments, a volume of approximately 1%-25% of the fan-coil airflow may enter the scrubber 200. In some embodiments, a volume of approximately 1%-10% of the fan-coil airflow may enter the scrubber 200. The remaining return air 150, which bypassed the scrubber 200, may flow directly through the fan-coil unit 128 or to the indoor space 120.

(34) The scrubber fan 224 may be placed in any suitable location within the scrubber 200, such as upstream in a push mode, i.e. intermediate the entry port 226 and the CO.sub.2 scrubber 204. Alternatively, as seen in FIG. 1, the scrubber fan 224 may be placed downstream in a pull mode i.e. after the CO.sub.2 scrubber 204.

(35) The return air 150 may flow through the filter 216, CO.sub.2 scrubber 204 and/or the VOC scrubber 214. The now scrubbed air flows out of the scrubber 200 via an exit port 230 including an exit damper 232, when positioned in an open state. The scrubbed air flows into the fan-coil unit 128 and may be conditioned by being cooled or heated therein. The conditioned air 160 may flow from the fan-coil unit 128 into the indoor space 120.

(36) Scrubbing the return air within the scrubber 200, according to some embodiments, allows reducing or eliminating the volume of fresh, outdoor air 180, which is required to provide for maintaining good air quality therein. Accordingly, the energy required to condition the outdoor air 180 is reduced or eliminated. Additionally, introduction of potential pollutants and contaminants from the outdoor air 180 into the enclosed environment 102 is reduced or eliminated. In some embodiments the volume of fresh, outdoor air 180 may be reduced approximately to a minimally required volume of the exhausted air 170, so as to maintain pressure equilibrium within the enclosed environment 102. Moreover, superior indoor air quality is provided.

(37) The volume of fresh, outdoor air 180 may be reduced in any suitable manner such as by reducing the volume of outdoor air 180 prior to flow in ducts 184 or by partially or fully closing dampers (not shown) within the enclosed environment 102 for controlling the volume of outdoor air 180 introduced therein.

(38) Following the capture and scrubbing of the contaminants in the scrub cycle, the adsorbent material may be regenerated during the purge cycle by urging the release of the contaminants from the adsorbent material.

(39) The regeneration may be performed in any suitable manner. For example, in some embodiments, regeneration may be performed by streaming a purge gas 240 over and/or through the adsorbent material for release of at least a portion of the contaminants therefrom.

(40) For example, during the purge cycle the purge gas 240 flows into the scrubber 200 via an entry conduit 244 including an entry damper 246, when positioned in an open state, while the entry damper 228 and exit damper 232 may be closed. A fan 247 may be provided for urging flow of the purge gas 240 within the scrubber 200. The fan 247 may be placed in any suitable location, such as in an exhaust conduit 248. Alternatively, the fan 247 may be omitted.

(41) Thus, in some embodiments, it is seen that switching the scrubber operation from the scrub cycle to the purge cycle may be performed by the dampers and/or fans or any other suitable means.

(42) In accordance with some embodiments the purge gas 240 comprises outdoor air.

(43) The outdoor air may be provided to the scrubber 200 from any source of outdoor air. For example, the source of outdoor air may be ambient air flowing directly from the ambient, i.e. out of the enclosed environment 102, into the scrubber 200, as shown in FIG. 1. Alternatively, the outdoor air may flow from the ambient into the scrubber 200 via ducts (not shown). Additionally, the source of outdoor air may be from other locations near the space 120, such as from a pier or elevator shaft.

(44) As shown in FIGS. 1-3, in some embodiments, the purge gas 240 may flow during the purge cycle in the opposite direction of the return air flow during the scrub cycle, such as from entry conduit 244 to the exhaust conduit 248. Alternatively, the purge gas 240 may flow during the purge cycle in the same direction of the return air flow, such as from exhaust conduit 248 to entry conduit 244.

(45) The exhaust conduit 248 may include an exit damper 250.

(46) It is noted that the entry conduit 244 may be replaced by an aperture allowing the purge gas 240 to flow into the scrubber 200. The exhaust conduit 248 may be replaced by any exhaust allowing the purge gas 240 to flow out of the scrubber 200.

(47) As seen in FIGS. 1-11C, in some embodiments, the purge gas 240 exiting the exhaust conduit 248 is discharged into the ambient, out of the enclosed environment 102. Alternatively, the purge gas 240 may flow out of the exhaust conduit 248 to existing exhaust ducts in the enclosed environment such as an air exhaust typically furnished in a bathroom of the enclosed environment 102 or openings such as windows. Additionally, purge gas 240 exiting the exhaust conduit 248 may flow to a volume in the enclosed environment 102, such as a stairwell, sewerage system or smoke control systems. Moreover, purge gas 240 may be directed to flow into a pressure vessel (not shown) for eventual release of the purge gas 240 therefrom.

(48) The purge gas 240 may be heated prior to regeneration of the scrubber 200 by any suitable method, as will be further described in reference to FIGS. 10A and 10B.

(49) In accordance with some embodiments, the purge gas 240 may be heated within a range of approximately 20-120 C. In accordance with some embodiments, the purge gas 240 may be heated to a temperature of less than 80 C. In accordance with some embodiments, the purge gas 240 may be heated to a temperature of less than 50 C. In accordance with some embodiments, the purge gas 240 may enter the scrubber 200 at the ambient temperature.

(50) Regeneration of the adsorbent material removes the contaminants from the adsorbent material. Therefore, the scrubber 200 can be repeatedly used for removing contaminants from the indoor space 120 without requiring replacement of the adsorbent material. Accordingly, the scrubber 200 described herein has a significantly long operating life.

(51) In the distributed air circulation system 110, according to some embodiments, the flow of the return air 150 into and out of the scrubber 200 and into and out of the fan-coil unit 128 may be at least partially ductless. For example, as shown in FIGS. 1-3, the flow of the return air 150 into the scrubber 200 is ductless and a portion of the return air 150 is urged by the scrubber fan 224 to flow from the air plenum 124 into the scrubber 200. The flow of the return air 150 from the air plenum 124 into the fan-coil unit 128 is shown to be ductless and is urged by the fan 134 to flow therein. The flow of the conditioned air out of the fan-coil unit 128 may be ductless or, as shown in FIGS. 1-3, the duct 168 is provided.

(52) In some embodiments, such as seen in FIGS. 1 and 2, the scrubbed air exiting the scrubber 200 may flow into the air plenum 124 and enter into the fan-coil unit 128 without a duct.

(53) In other embodiments, as seen in FIG. 3, the scrubbed air exiting the scrubber 200 may flow into the fan-coil unit 128 via a duct 250.

(54) In FIG. 4, a system 254 for conditioning air in the enclosed environment 102 is substantially similar to the respective systems 100, 104 and 106 of FIGS. 1-3. As seen in FIG. 4, exhaust ports 172 or 176 are not included and similarly outdoor air 180 is not introduced into the indoor spaces 120 or the air plenum 124. A portion of the return air 150 is scrubbed in the scrubber 200, thereby providing good air quality to the indoor space 120. Therefore, introduction of the fresh, outdoor air 180 for maintaining good air quality is unnecessary and the energy required to condition the outdoor air 180 is also eliminated. Additionally, introduction of potential pollutants and contaminants from the outdoor air 180 into the enclosed environment 102 is eliminated.

(55) A portion of the return air 150 may initially flow to the scrubber 200 and thereafter the scrubbed air may flow into the fan-coil unit 128, as shown in FIGS. 1-4. Alternatively, the return air 150 may initially flow through the fan-coil unit 128, as shown in FIG. 5.

(56) In FIG. 5, a system 258 for conditioning air in the enclosed environment 102 is shown. As seen in FIG. 5, the return air 150 initially flows into the fan-coil unit 128. A portion 260 of the conditioned air exiting the fan-coil unit 128 may be directed into the indoor space 120 and a portion 262 of the conditioned air may flow into the scrubber 200. The scrubbed air exiting the scrubber 200 may be directed into the indoor space 120.

(57) In some embodiments the fan-coil unit 128 may be placed in the air plenum 124, as seen in FIGS. 1-5. In other embodiments the fan-coil unit 128 may be placed within the indoor space 120 on a floor 270 (FIG. 6) or in proximity thereto, near a wall 274 or on a ceiling 276 or in proximity thereto. The scrubber 200 may be placed in the air plenum 124, as seen in FIGS. 1-5. In other embodiments the fan-coil unit 128 may be placed within the indoor space 120 under the floor 270 or in proximity thereto, near the wall 274 or in proximity thereto or on the ceiling 276 or in proximity thereto.

(58) In FIG. 6 a system 278 for conditioning air in the enclosed environment 102 is shown. In the left side indoor space 120 the fan-coil unit 128 is shown to be mounted horizontally beneath the ceiling 276 and in the right side indoor space 120 the fan-coil unit 128 is shown to be mounted vertically on the wall 274. The indoor air, illustrated by arrows 280, circulates within the indoor space 120. A portion of the indoor air 280 may enter the scrubber 200. The scrubber 200 may be placed in any suitable location within the indoor space 120, such as in proximity to the ceiling 276, for example.

(59) The scrubbed air exits the scrubber 200 into the indoor space 120 for further circulation thereof.

(60) In FIG. 7, a system 288 for conditioning air in the enclosed environment 102 is shown. As seen in FIG. 7, the enclosed environment 102 may comprise a single indoor space 120. A plurality of fan-coil units 128 may be provided for conditioning the return air 150 and circulating the conditioned air back into the indoor space 120. The plurality of fan-coil units 128 may be placed in the air plenum 124, as shown in FIG. 7, or in any suitable location within the indoor space 120, as described in reference to FIG. 6.

(61) A single scrubber 200 may be provided to scrub the indoor air, as shown in FIG. 7, or a plurality of scrubbers 200 may be provided. In some embodiments each scrubber 200 may be associated with a specific fan-coil unit 128. In some embodiments the plurality of scrubbers 200 may be placed within the indoor space 120 and may not be associated with a specific fan-coil unit 128.

(62) The scrubber 200 may be placed in any suitable location within the enclosed environment 102 as described in reference to FIG. 6. In FIG. 7 the scrubber is placed within the indoor space 120.

(63) In some embodiments, as shown in FIG. 7, a portion of the indoor air 280 may be exhausted out of the enclosed environment via exhaust ports 286. Fresh, outdoor air 180 may be introduced into the indoor space 120 or any other suitable location, via a duct 290. In some embodiments the fresh, outdoor air 180 may be cooled or heated prior to entrance into the enclosed environment by a fresh air, pre-conditioning unit 292, thereby reducing a degree of cooling or heating required by the fan-coil units 128.

(64) Scrubbing the indoor air 280 within the scrubber 200 allows for reducing the volume of fresh, outdoor air 180 required for maintaining good air quality within the indoor space 120. Accordingly, the energy required to condition the outdoor air 180 is reduced. Additionally, introduction of potential pollutants and contaminants from the outdoor air 180 into the enclosed environment 102 is reduced.

(65) In some embodiments, fresh, outdoor air 180 may not be introduced into the enclosed environment 102 of FIG. 7.

(66) In FIG. 8, a system 300 for conditioning air in the enclosed environment 102 is shown. As seen in FIG. 8, the enclosed environment 102 comprises a plurality of indoor spaces 120 each associated with its fan-coil unit 128. In a non-limiting example shown in FIG. 8, the fan-coil units 128 are set above the ceiling, within or without the air plenum 124. The fan-coil units 128 may have a common supply of a refrigerant fluid supplied from a shared chiller or heat pump (not shown). In accordance with some embodiments, the refrigerant fluid may comprise chilled water or may be supplied by a variable refrigerant flow (VRF) system. A portion of return air 304 may flow out of each indoor space 120 directly to the fan-coil unit or into the air plenum 124. This portion of the return air 304 may flow into the fan-coil unit 128 for conditioning thereof and circulation into the indoor space 120. Some of the return air 304 may be exhausted out of the enclosed environment 102, such as via exhaust ports 310 located in each of the air plenums 124 or any other suitable location.

(67) Another portion of return air 314 may be directed to flow into a shared scrubber 200, via conduits 320 or without conduits by any other suitable manner. In some embodiments the conduits 320 may be installed specifically for flow into the scrubber 200. In other embodiments existing conduits or ducts in the enclosed environment (e.g. building) may be used, such as standard ducts provided for ventilation or elevators or for exhaust such as smoke exhaust.

(68) Scrubbed air, exiting the scrubber 200, may be introduced back into the indoor spaces 120 via conduits 324 or in any other suitable manner. In some embodiments conduits 324 may comprise existing indoor air conduits or ducts, such as ducts 184 of FIG. 1. The scrubbed air may initially flow from the scrubber 200 into a fresh air pre-conditioning unit 330, such as the fresh air pre-conditioning unit 292 shown in FIG. 7. The scrubbed air may be cooled or heated within the fresh air pre-conditioning unit 330 prior to flow in conduits 324, thereby reducing a degree of cooling or heating required by the fan-coil units 128. The scrubbed air may flow from the scrubber 200 into the fresh air pre-conditioning unit 330 via a conduit 334 or by any other suitable means.

(69) In some embodiments a plurality of scrubbers 200 may be provided.

(70) The scrubber 200 may be placed in a suitable location, such as on a roof 338 of the enclosed environment 102 or out of the enclosed environment 102 or within the enclosed environment 102 such as in a mechanical room or any other location.

(71) Scrubbing the return air 314 within the scrubber 200 allows for reducing the volume of fresh, outdoor air 340 required for maintaining good air quality within the indoor space 120. In some embodiments, such as wherein exhaust ports 310 are not provided, introduction of fresh, outdoor air 340 may be eliminated.

(72) In FIG. 9A-9E a system 400 for conditioning air in the enclosed environment 102 is shown. As seen in FIG. 9A an integrated fan-coil unit 410 comprises a housing or mechanical frame 412 that is connecting or otherwise shared by the scrubber 200 and the fan-coil unit 128. Return air 150 may enter the integrated unit 410 via an entry port 416 and may be initially filtered by filter 158. Thereafter, a portion of the return air 150 may be scrubbed within the scrubber 200 and a remaining portion of return air may bypass the scrubber 200. The scrubbed air and the bypassed air are urged by the fan 134 to flow to the coils 136 to be cooled or heated thereby. The conditioned air may exit the integrated unit 410 via an exit port 414 and duct 416 so as to be circulated into the indoor space 120.

(73) In the embodiment shown in FIG. 9A, the scrubber 200 is placed prior to the fan 134 and coils 136, in respect to the direction of the return air flow. In the embodiment shown in FIG. 9B, an integrated unit 420 is provided and the scrubber 200 is placed intermediate the fan 134 and coils 136. In the embodiment shown in FIG. 9C an integrated unit 430 is provided and the scrubber 200 is placed after the fan 134 and coils 136, in respect to the direction of the return air flow.

(74) In the embodiment shown in FIG. 9D, an integrated unit 440 is provided. The entry port 226 to the scrubber 200 is provided following the fan 134 and the coils 136. The exit port 230 is placed intermediate the fan 134 and coils 136. Return air 150 flowing into the integrated unit 440 may flow through filter 158. The fan 134 urges the return air 150 to flow to the coils 136 for cooling or heating thereby. A portion of the cooled or heated air may bypass the scrubber 200 and flow out of the integrated unit 440. A remaining portion of the cooled or heated air may be urged by scrubber fan 224 to enter the entry port 226 into the scrubber 200. The scrubbed air may exit the scrubber via exit port 230 and may be cooled or heated again by the coils 136 prior to flowing out of the integrated unit 440.

(75) In the embodiment shown in FIG. 9E, an integrated unit 450 is provided. Here the entry port 226 to the scrubber 200 is positioned following the coils 136. The fan 134 is positioned intermediate the coils 136 and the entry port 226. The exit port 230 is placed prior the coils 136. Return air 150 flowing into the integrated unit 450 may flow through filter 158. The fan 134 urges the return air 150 to flow to the coils 136 for cooling or heating thereby. A portion of the cooled or heated air may bypass the scrubber 200 and flow out of the integrated unit 450. A remaining portion of the cooled or heated air may be urged by fan 134 to enter the entry port 226 into the scrubber 200. The fan 134 of the fan-coil unit 128 may be sufficient for urging the cooled or heated air to flow into the scrubber 200 and the scrubber fan may be eliminated. The scrubbed air may exit the scrubber via exit port 230 and may be cooled or heated again by the coils 136 prior to flowing out of the integrated unit 450.

(76) The integrated units 410, 420, 430, 440 and 450 may be placed within the air plenum 124, as shown in FIGS. 9A-9E, or within the indoor space 120 or any other suitable location.

(77) Use of an integrated unit, such as shown in FIGS. 9A-9E, simplifies the installation or connection of the scrubber 200 and fan-coil unit 128. Additionally, in some embodiments, components of the fan-coil unit 128 may be used for the scrubber 200. For example the fan 134 may be used to aid in directing air into the scrubber 200, and may even eliminate the need for a separate scrubber fan, as seen in FIG. 9E. Moreover, the purge gas 240 may be heated by heating coil 140 or other heating means within the fan-coil unit 128.

(78) As described in reference to FIGS. 1-9E, the purge gas 240 may be heated prior to flow into the scrubber 200. Additionally, the purge gas 240 may be heated within the scrubber 200, such as in entry conduit 244. The purge gas 240 may be heated in any suitable manner. For example, the purge gas 240 may be heated by an electric heating coil, a coil or radiator with heated fluid supplied from a central heating system in the enclosed environment 102, solar heat, such as solar heat provided to the enclosed environment 102, an appropriately sized furnace burning gas or other fuel (not shown) for heating the purge gas 240. Some additional exemplary methods are described in reference to FIGS. 10A and 10B.

(79) In FIG. 10A, a system 500 for conditioning air in the enclosed environment 102 is shown. In accordance with some embodiments, a warm fluid may be used to heat the purge gas 240. For example, a fluid coil 510, such as a copper or other metal tube, is placed at the entry conduit 244 and the coil 510 is supplied with warm fluid. In some embodiments, the warm fluid may be heated within a heating plant or boiler (not shown) provided specifically for heating the purge gas 240. In some embodiments, the warm fluid may be heated by an existing supply of warm fluid provided in a standard enclosed environment 102, such as a building's hot water supply or the warm fluid provided to the heating coils 140 of the fan-coil unit 128.

(80) In FIG. 10B, a system 600 for conditioning air in the enclosed environment 102 is shown where, according to some embodiments, a heat pump 610 may be utilized to heat the purge gas 240. Typically, the heat pump 610 comprises a condenser side, or a hot side 620. The purge gas 240 may directly contact the hot side 620 and may be heated thereby. Alternatively, a heating element 624 may be heated by the hot side 620 and the purge gas 240 may be heated by the heating element 624. Additionally, the hot side 620 may be used to directly heat the adsorbent material in the scrubber 200. Use of a heat pump 610 may be advantageous, since to operate the heat pump 610 less power is required than other heating means, such as electric heating, for example.

(81) In some embodiments, an evaporator side or a cold side 630 of the heat pump 610 may be used to remove heat from the return air 150 flowing within the air plenum 124, or the air flowing through the fan coil unit, or any other air within the indoor space 120. The now cooled air directly or indirectly lessens the cooling power required by the fan-coil unit 128.

(82) In FIGS. 11A-11D, respective systems 700, 710, 720 and 730 for conditioning air in the enclosed environment 102 according to some embodiments are shown. As seen in FIGS. 11A-11C, the systems 700, 710, 720 are similar to the system 100 of FIG. 1.

(83) In accordance with some embodiments, an air ionizer 750 or air purifier may be provided at any suitable location within the enclosed environment 102 to enhance the air quality therewithin. The air ionizer 750 typically emits electrically charged ions that clean impurities from the air within the enclosed environment 102. The air ionizer 750 may be provided to otherwise improve air quality within the enclosed environment 102.

(84) The air ionizer 750 may be placed at any suitable location. For example, as seen in FIG. 11A, the air ionizer 750 is placed in the center of the indoor space 120. Additionally, the air ionizer 750 may be mounted to the wall 274 or ceiling 276 of the indoor space 120 or any other suitable location within the enclosed environment 102.

(85) As seen in FIG. 11B, the air ionizer 750 may be associated with the fan-coil unit 128, and may be placed in the duct 168, for example. Turning to FIG. 11C, it is seen that the air ionizer 750 may be placed within the scrubber 200 at any suitable location, such as intermediate the filter 158 and the CO.sub.2 scrubber 204, for example.

(86) In accordance with some embodiments, a microorganism removal device 760 may be provided for removal of microorganisms including, inter alia, bacteria, viruses, molds and fungi, from the enclosed environment 102 in any suitable manner. In a non-limiting example the removal device 760 may comprise an ultraviolet anti-microbial device. The removal device 760 may include an air filter with a media formed of foam, paper, fiberglass, oxides, catalysts, or any other suitable material. Additionally the removal device 760 may remove the microorganisms using an ozone source, a source of radiation, ion or plasma generators, chemical catalysts, a membrane and/or a heater.

(87) The removal device 760 may be placed at any suitable location. For example, as seen in FIG. 11A, the removal device 760 is placed in the center of the indoor space 120. Additionally, the removal device 760 may be mounted to the wall 274 or ceiling 276 of the indoor space 120 or any other suitable location within the enclosed environment 102.

(88) As seen in FIG. 11B, the removal device 760 may be associated with the fan-coil unit 128, and may be placed in duct 168, for example. Turning to FIG. 11C, it is seen that the removal device 760 may be placed within the scrubber 200 at any suitable location, such as intermediate the filter 158 and the CO.sub.2 scrubber 204, for example.

(89) It is noted that additional contaminant removal devices may be provided within the systems of FIGS. 1-11D. For example, a device for removing dust in any suitable manner may be provided or a plasma generator, or chemical catalysts may be provided.

(90) It is noted that the air ionizer 750 and the microorganism removal device 760 may be placed in any one of the systems shown in FIGS. 1-10B.

(91) In FIG. 11D, the system 730 for conditioning air in an enclosed environment 802 is shown. The enclosed environment 802 may be similar to enclosed environment 102 of FIGS. 1-11C. As seen in FIG. 11D, the system 730, according to some embodiments, may comprise a conventional air handling unit 810 for conditioning the circulated indoor air of the enclosed environment 802 and ducts 812 for directing the indoor air flow within the system 800. Return air 814 may exit the enclosed environment 802, which may be partially exhausted as exhaust air 818, via exhaust ducts 820, into the ambient, and may be partially reintroduced into the enclosed environment 802. A portion of the return air 814 may be introduced into the scrubber 800 prior to flow back into the enclosed environment 802. Fresh, outdoor air 830 may be introduced into the system 730 via ducts 834.

(92) In accordance with some embodiments, the air ionizer 750 may be provided at any suitable location, such as within the enclosed environment 802 or at an entrance thereto.

(93) The microorganism removal device 760 may be provided at any suitable location, such as within the enclosed environment 802, or at an entrance thereto or exit therefrom. Additionally, the removal device 760 may be placed before entry or after the exit to the scrubber 200.

(94) Moreover the air ionizer 750 or removal device 760 may be placed within the scrubber 200, such as the scrubber shown in FIG. 11C.

(95) It is noted in reference to FIGS. 1-11D, that any other suitable means besides dampers, such as valves, fans or shutters, may be used to control the volume of air entering and/or exiting the fan-coil unit 128 or the scrubber 200.

(96) In some embodiments of the systems shown in FIGS. 1-11D, a single or plurality of sensors (not shown) may be provided to detect levels of one or more contaminants, substances, gases (such as CO.sub.2 and other gases), fumes, vapors, (such as VOCs) and/or any combination thereof. The sensors may be placed in any suitable location within the enclosed environment 102 or in proximity thereto. Upon detection of a particular concentration of such contaminants, substances, gases, etc., the sensor(s) may be configured to generate output data that can be transmitted to a control system (not shown) for processing thereof.

(97) The control system may be operative to control any one or more of: the duration of time the scrub cycle and the purge cycle, the volume of air flowing into the scrubber for scrubbing thereof, the volume of purge gas flowing into the scrubber for regeneration of the scrubber, and switching of the scrubber from the scrub cycle to the purge cycle and vice versa.

(98) In some embodiments, the control system may be designed to control the duration and air volume during the scrub cycle and the purge cycle and switching of the scrubber from the scrub cycle to the purge cycle and vice versa, according to a preset schedule, or by sensing a predetermined level of the contaminants by the sensors and accordingly operating the scrub cycle or purge cycle, or by determining an occupancy level of the indoor space 120 and, accordingly, operating the scrub cycle or purge cycle, for example. The duration or volume during the scrub cycle or purge cycle and switching therebetween may be controlled by a manual trigger or by externally signaled commands or any other suitable means.

(99) In some embodiments, the control system may be designed to activate the scrubber in response to actual contaminant levels, occupancy, or preset schedules.

(100) It is noted that the ducts disclosed throughout the application may comprise conduits, pipes or any suitable means for directing air to flow therethrough.

(101) Example embodiments of the methods and components of the current subject matter have been described herein. As noted elsewhere, these example embodiments have been described for illustrative purposes only, and are not limiting. Other embodiments are possible and are covered by the current subject matter. Such embodiments will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein. Moreover, a feature(s) from one embodiment(s) may be used in combination or in place of a feature(s) of another embodiment(s). Thus, the breadth and scope of the current subject matter should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.