Modular air sanitation unit

Abstract

Disclosed are air sanitation units having one or more photocatalytic oxidation (PCO) devices, a fan for moving air through the PCO devices, and a duct for directing the airflow. Additional embodiments are described for increasing the flow rate of air through the PCO devices, improving the concentration of generated oxidizer in the airflow, and reducing the energy demand of the unit.

1 . An air sanitation unit, comprising:
 a duct including an inlet and an outlet for directing airflow through the unit,   one or more photocatalytic oxidation (PCO) devices disposed within the duct, wherein each PCO device includes:
 a frame having a length, width, and height, with a longitudinal axis extending through the length of the frame, 
 a pair of cell panels disposed opposite one another across the width of the frame, an interior portion of the frame between the cell panels defining an interior chamber, the cell panels including a plurality of apertures to allow air to flow into and through the interior chamber, and at least interior surfaces of the cell panels and aperture surfaces of the cell panels including a photocatalytic material, and 
 an ultraviolet lamp disposed within the interior chamber and extending along the longitudinal axis; and 
   a fan configured to move surrounding air into the inlet, through the one or more PCO devices, and through the outlet.   
     
     
         2 . The air sanitation unit of  claim 1 , wherein the fan is positioned upstream of the one or more PCO devices such that surrounding air is pushed through the one or more PCO devices. 
     
     
         3 . The air sanitation unit of  claim 1 , wherein the fan is positioned downstream of the one or more PCO devices such that surrounding air is pulled through the one or more PCO devices. 
     
     
         4 . The air sanitation unit of  claim 1 , wherein the fan comprises a cross flow fan. 
     
     
         5 . The air sanitation unit of  claim 1 , wherein approximately all of the airflow through the duct passes through the one or more PCO devices. 
     
     
         6 . The air sanitation unit of  claim 1 , wherein the duct includes an inverted funnel disposed upstream of the one or more PCO devices. 
     
     
         7 . The air sanitation unit of  claim 1 , wherein the unit includes two or more PCO devices. 
     
     
         8 . The air sanitation unit of  claim 7 , wherein the unit comprises a first PCO device and a second PCO device, the first and second PCO devices being vertically aligned such that the airflow passes through either the first or second PCO device. 
     
     
         9 . The air sanitation unit of  claim 7 , wherein the unit comprises a first PCO device and a second PCO device, the first and second PCO devices being horizontally aligned such that the airflow first passes through the first PCO device and then through the second PCO device. 
     
     
         10 . The air sanitation unit of  claim 1 , further comprising one or more additional cell panels, the additional cell panels including a plurality of apertures to allow air to flow into and through the interior chamber, and at least interior surfaces of the additional cell panels and aperture surfaces of the additional cell panels including a photocatalytic material. 
     
     
         11 . The air sanitation unit of  claim 10 , wherein one or more additional cell panels are positioned upstream of the one or more PCO devices. 
     
     
         12 . The air sanitation unit of  claim 10 , wherein one or more additional cell panels are positioned downstream of the one or more PCO devices. 
     
     
         13 . The air sanitation unit of  claim 10 , wherein a surface of a major plane of at least one additional cell panel is oriented at an oblique angle relative to a major plane of at least one of the cell panels of the one or more PCO devices. 
     
     
         14 . The air sanitation unit of  claim 13 , wherein the oblique angle of the additional cell panel is within a range of greater than 0 degrees to approximately 60 degrees. 
     
     
         15 . The air sanitation unit of  claim 10 , wherein the unit comprises:
 an upstream additional cell panel positioned upstream of the one or more PCO device, a major plane of the upstream additional cell panel is oriented at an oblique angle relative to a surface of a major plane of at least one of the cell panels of the one or more PCO devices, and   a first and second downstream additional cell panel positioned downstream of the one or more PCO devices, wherein:
 a major plane of the first downstream additional cell panel is oriented at an oblique angle relative to the surface of the major plane of at least one of the cell panels of the one or more PCO devices, and 
 a second downstream additional cell panel is positioned downstream of the first downstream additional cell panel and a major plane of the second downstream additional cell panel is parallel to the major plane of at least one of the cell panels of the one or more PCO devices. 
   
     
     
         16 . An air sanitation unit, comprising:
 a photocatalytic oxidation device that includes:
 a frame having a length, width, and height, with a longitudinal axis extending through the length of the frame, 
 a pair of cell panels disposed opposite one another across the width of the frame, an interior portion of the frame between the cell panels defining an interior chamber, the cell panels including a plurality of apertures to allow air to flow into and through the interior chamber, and at least interior surfaces of the cell panels and aperture surfaces of the cell panels including a photocatalytic material, and 
 an ultraviolet lamp disposed within the interior chamber and extending along the longitudinal axis; 
   wherein the device is located within an air duct.   
     
     
         17 . The air sanitation unit of  claim 16 , wherein the unit is configured to activate when an airflow through the air duct fails to reach a minimum flow rate. 
     
     
         18 . The air sanitation unit of  claim 17 , wherein the unit is connected to an airflow sensor, and wherein the unit is configured to activate when the airflow sensor fails to detect a minimum airflow through the air duct. 
     
     
         19 . The air sanitation unit of  claim 16 , further comprising:
 a fan in fluid communication with the air duct, the fan being configured to provide an airflow through the air duct;   wherein the air duct forms part of a ventilation system, the ventilation system being connected to one or more ventilation devices; and   wherein the air sanitation unit and the one or more ventilation devices are connected to a system that activates the fan of the air sanitation unit when the one or more ventilation devices do not produce an airflow through the air duct.   
     
     
         20 . The air sanitation unit of  claim 19 , wherein the air sanitation unit is connected to an interlock system configured to control access to an environment in fluid communication with the ventilation system during operation of the air sanitation unit.