Methods and systems for managing air quality and energy use in air-conditioning systems

Patent metadata

Field	Value
Publication number	US-9328936-B2
Application number	US-201313738737-A
Country	US
Kind code	B2
Filing date	Jan 10, 2013
Priority date	Jan 10, 2012
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

Methods and systems for a heating, ventilation, and air-conditioning (HVAC) system for an enclosed environment may be configured to at least one of heat and cool air and include an air circulation system configured to circulate air at least within the enclosed environment. The air within the enclosed environment may comprise at least the indoor air. The system may further include an outdoor air inlet for introducing at least a portion of outdoor air into the enclosed environment, where the outdoor air comprises air from outside the enclosed environment. The system may further include a scrubbing system having an adsorbent material to reduce presence of at least one gas contaminant in the indoor air. A controller system may be included for controlling the operation of at least one of the circulation system and the scrubbing system.

First claim

What is claimed is:

1. A method of operating a heating, ventilation, and air-conditioning (HVAC) system for an enclosed environment, the HVAC system configured to at least one of heat and cool air and comprising:
an air circulation system configured to circulate air at least within the enclosed environment, the air within the enclosed environment comprising indoor air;
an outdoor air inlet for introducing at least a portion of outdoor air into the enclosed environment, the outdoor air being from outside the enclosed environment;
a scrubbing system including an adsorbent material to reduce presence of at least one gas contaminant in the indoor air; and
a controller system for controlling at least the operation of the outdoor air inlet and the scrubbing system, the controller system configured to include:
a scrubbing bypass mode wherein either circulated air bypasses the scrubbing system or the scrubbing system is turned off or both, the scrubbing bypass mode configured to be activated when a level of at least one gas contaminant of air exiting the scrubbing system exceeds a level of at least one gas contaminant of air entering the scrubbing system; and
one or more of at least the following operative modes:
a scrubbing mode to scrub the at least one gas contaminant from the indoor air;
a scrubber regeneration mode to regenerate the adsorbent material;
an economizer mode comprising introducing at least a portion of outdoor air into the enclosed environment via the outdoor inlet;
a standby mode, wherein neither indoor air nor outdoor air is circulated;

the method comprising:
determination of at least one of the following parameters:
an occupancy level of the enclosed environment;
a level of the at least one contaminant in the indoor air;
a level of the at least one contaminant in the adsorbent material;
a level of the at least one contaminant in air exiting the adsorbent material;
at least one of an indoor air temperature and an indoor air humidity level;
at least one of an outdoor air temperature and an outdoor air humidity level; and
at least one of a time and a date the HVAC system is operating;

and
controlling activation of the air circulation system and the scrubbing system according to the operative modes based upon the at least one parameter.

2. The method of claim 1 , wherein the operative mode is operated by controlling at least one of the following components of the air circulation system: fans, dampers, shutters, valves and heaters, configured to affect flow of air or other fluids in the HVAC system.

3. The method of claim 1 , wherein upon the occupancy level being at or below a predetermined number of people, or the time and date being outside of normal operating hours, the HVAC system is operated according to the standby mode or according to the scrubbing bypass mode.

4. The method of claim 1 , wherein the scrubber regeneration mode is activated upon the occurrence of at least one of the following:
a predetermined time of day;
following a predetermined duration of the scrubbing system operation in the scrubbing mode;
the level of the at least one gas contaminant in the adsorbent material being at or above a predetermined threshold; and
the level of the at least one contaminant in air exiting the adsorbent material being at or above a predetermined threshold.

5. The method of claim 1 , wherein the scrubber regeneration mode is operated for a period of time according to at least one of the following:
a predetermined period of time from the start of activation of the regeneration operative mode;
the level of the at least one gas contaminant in the adsorbent material;
the level of the at least one contaminant in air exiting the adsorbent material;
the level of the at least one contaminant in the indoor air;

a predetermined period of time after the level of the at least one gas contaminate contaminant in the adsorbent material being at or below a predetermined threshold;
a predetermined period of time after the level of the at least one contaminant in air exiting the adsorbent material being at or below a predetermined threshold; and
a predetermined period of time after the level of the at least one contaminant in the indoor air being above a predetermined threshold.

6. The method of claim 5 wherein the predetermined period of time is determined according to any one of:
at least one of the time and the date the HVAC system is operating; and
at least one of the outdoor air temperature and the outdoor air humidity level.

7. The method of claim 1 , wherein the scrubber regeneration mode comprises flowing a purging airflow over the adsorbent material so as to eliminate at least a portion of the at least one gas contaminant held by the adsorbent material.

8. The method of claim 7 wherein the purging airflow comprises outdoor air having at least one of a temperature and a flow rate equal to or greater than a corresponding threshold value.

9. The method of claim 7 wherein the scrubber regeneration mode comprises operation at a plurality of different phases, wherein a single phase is selected to operate at any one of:
a temperature of the purge air;
a duration of the purging airflow over the adsorbent material; and
flow rate of the purging airflow over the adsorbent material.

10. The method of claim 1 , wherein the economizer mode comprises introducing into the enclosed environment at least a portion of outdoor air to reduce the amount of recirculated indoor air required to be conditioned or treated.

11. The method of claim 1 , wherein the economizer mode is selected based upon a comparison between one or more of the outdoor air temperature and the humidity level relative to the corresponding one or more of temperature and humidity level of indoor air or relative to the corresponding one or more of temperature and humidity level of return air, wherein the return air is the indoor air exiting the enclosed environment.

12. The method of claim 1 , wherein the scrubbing bypass mode is activated upon the level of the at least one gas contaminant present in the indoor air being at or below a predetermined level.

13. The method of claim 1 , wherein the scrubbing mode is activated upon the level of the at least one gas contaminant present in the indoor air is at or greater than a predetermined level.

14. The method of claim 1 , wherein the parameters further include at least one of the following: a HVAC operation schedule, temperature, humidity, pressure, flow rate, and energy expenditure of a HVAC refrigerant, chiller, compressor and heat pump.

15. The method of claim 1 , wherein the level of the at least one gas contaminant in the adsorbent material is determined based on the level of the at least one gas contaminant in air exiting the scrubbing system to the level of the at least one gas contaminant in air entering the scrubbing system.

16. The method of claim 1 , wherein the regeneration mode is operative to eliminate at least about 35% of the at least one gas contaminant that has been adsorbed in the adsorbent material.

17. The method of claim 1 , wherein upon the scrubbing system malfunctioning, a predetermined amount of outdoor air is introduced into the enclosed environment.

18. The method of claim 1 , wherein upon the scrubbing system malfunctioning, the system provides an alert.

19. The method of claim 1 , wherein the at least one gas contaminant is selected from the group consisting of: carbon dioxide, volatile organic compounds, sulfur oxides, radon, nitrous oxides and carbon mono

Assignees

• Enverid Systems Inc

Inventors

• Meirav Udi
• Biran Israel
• Meruham Asael

Classifications

• F24F2011/0002

  for admittance of outside air · CPC title

• F24F2110/66

  Volatile organic compounds [VOC] · CPC title

• F24F2110/22

  of the outside air · CPC title

• F24F11/30

  for purposes related to the operation of the system, e.g. for safety or monitoring · CPC title

• F24F11/0001 Primary

  for ventilation (F24F11/30 takes precedence) · CPC title