Patent Application
20230127012
The present disclosure relates generally to reducing airborne contaminants and, more particularly, to reducing airborne contaminants using ultraviolet (UV) energy.
Ultraviolet (UV) light is a form of electromagnetic radiation with wavelength shorter than that of visible light, but with a wavelength longer than X-rays. UV light is known to interact with organic molecules. More particularly, deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and proteins can absorb deep UV light, e.g., in the range of 200 nanometers (nm) to 300 nm, which can lead to rupture of a cell, disruption of DNA replication, and other molecular damage. As such, UV light is sometimes used to disinfect surfaces that might contain bacteria, mold, virus, etc.
The present disclosure is directed to photocatalytic systems for reducing airborne contaminants using an ultraviolet (UV) emitter and photocatalytic cells.
Some embodiments include a photocatalytic system for reducing airborne contaminants using an ultraviolet (UV) emitter and photocatalytic cells. For such embodiments, the system comprises a side wall with a wall top, a wall bottom, a wall front edge, and a wall back edge. The system further comprises a front slot that is located toward the wall front edge and a back slot that is located toward the wall back edge. The front slot is configured to secure a front photocatalytic cell, while the back slot is configured to secure a back photocatalytic cell. The side wall further comprises a non-planar reflective surface located between the front slot and the back slot. The non-planar reflective surface permits greater interaction between the UV rays from the UV emitter and the photocatalytic cells, thereby improving the performance of the photocatalytic system. For some embodiments, the non-planar reflective surface comprises a first protrusion and a second protrusion. The protrusions provide larger reflective surfaces as well as more-varied directionality of reflection, as compared to a flat surface.
Other systems, devices, methods, features, and advantages will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present disclosure, and be protected by the accompanying claims.
Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
In the presence of ultraviolet (UV) energy, photocatalytic cells produce cluster ions or ionized clouds that reduce airborne contaminants, such as bacteria, mold, or virus. As air passes through the photocatalytic cells, UV energy that strikes the photocatalytic cells results in a catalytic reaction that produces ionized molecules within the airflow. The ionized molecules neutralize some or all of the contaminants that are present in the air.
The effectiveness of photocatalytic systems depends on the concentration of ionized molecules. The concentration of ionized molecules is, in turn, dependent on both: (a) the amount of photocatalytic material on the photocatalytic cells (e.g., titanium dioxide coated on honeycomb structured cells); and, also (b) how much UV strikes the photocatalytic material. In other words, merely having more photocatalytic material (e.g., titanium dioxide) is insufficient if the photocatalytic material is not exposed to the UV energy.
To improve effectiveness of photocatalytic systems, several embodiments are disclosed, which provide for greater UV exposure to the photocatalytic materials. Specifically, some embodiments include a non-planar reflective surface. The non-planar surface permits greater interaction between UV rays and the photocatalytic cells. The increased interaction improves the performance of the photocatalytic system. For some embodiments, the non-planar reflective surface comprises a first protrusion and a second protrusion. The protrusions provide larger reflective surfaces as well as more-varied directionality of reflection, as compared to a flat surface.
Having provided a broad technical solution to a technical problem, reference is now made in detail to the description of the embodiments as illustrated in the drawings. While several embodiments are described in connection with these drawings, there is no intent to limit the disclosure to the embodiment or embodiments disclosed herein. On the contrary, the intent is to cover all alternatives, modifications, and equivalents.
Referring now to the drawings, one embodiment of a photocatalytic system 100 is shown in
For the embodiment shown, the housing 110 comprises side walls 140a, 140b (collectively labeled as 140), which are positioned substantially parallel to each other. For some embodiments, the side walls 140 are substantially rectangular in shape, with each side wall 140 having a wall top 142 and a wall bottom 144, with the wall bottom 144 being substantially parallel to the wall top 142.
Furthermore, each side wall 140 has a wall front edge 146, which extends substantially from the wall top 142 to the wall bottom 144, and a wall back edge 148, which is substantially parallel to the wall front edge 146 and also substantially extends from the wall top 142 to the wall bottom 144.
The housing 110 further comprises a housing top 150 that is mechanically coupled to the wall top 142, with the side wall 140 being at substantially right angles to the housing top 150, as shown in
The housing 110 further comprises a housing bottom 160 that is positioned substantially parallel to the housing top 150 and mechanically coupled to the wall bottom 144, with the side wall 140 being at substantially right angles to the housing bottom 160. The housing bottom 160 has a bottom front edge 162, a bottom back edge 164, and an opening 166 for receiving the UV emitter. The opening 166 is located between the bottom front edge 162 and the bottom back edge 164. For some embodiments, the housing bottom 160 is substantially rectangular in shape, while for other embodiments the housing bottom 160 is substantially square in shape.
When assembled, the wall front edge 146 extends substantially from the top front edge 152 to the bottom front edge 162. Similarly, the wall back edge 148 extends substantially from the top back edge 154 to the bottom back edge 164. Upon full assembly of the housing top 150, housing bottom 160, side walls 140, the photocatalytic cells 120, 130 and the UV emitter (not shown), the photocatalytic system 100 provides a substantially enclosed environment for the UV emitter.
For some embodiments, the UV emitter is an elongated UV bulb with a proximal end located near the housing bottom 160 and a distal end located near the housing top 150. Because UV bulbs are well known to those having skill in the art, further discussion of the UV bulb itself is omitted herein. In one embodiment, the UV bulb has a proximal end that is located near the housing bottom 160 and secured at its proximal end in or near the opening 166. The UV bulb also has a distal end, which, in some embodiments, is located near the housing top 150. In conventional systems, the distal end of the UV bulb is held by a foam block, which reduces movement of the UV bulb, but detrimentally blocks some of the UV rays from interacting with a portion of the photocatalytic cells.
Unlike foam-block-based systems, a preferred embodiment of the disclosed photocatalytic system 100 comprises a bracket (not shown) that is positioned near the housing top 150, with a substantially circular grommet (not shown) located in the bracket. The grommet is configured to secure the distal end of the UV bulb. In other words, rather than using a foam block (which is used in conventional systems), the disclosed embodiments use a grommet secured to a bracket, which blocks less of the UV rays and, therefore, increases the UV interaction with the photocatalytic cells 120, 130.
With this general configuration for a photocatalytic system 100 described with reference to
Specifically,
With this in mind, attention is turned to
To secure the front photocatalytic cell 120 in place, one embodiment of the front slot 215 comprises two (2) substantially parallel flanges 230, 235, which allow the front photocatalytic cell 120 to slide between the flanges 230, 235. As one can appreciate, the distance between the flanges 230, 235 is approximately the same as the width of the front photocatalytic cell 120 (or slightly larger but within a desired tolerance).
Similarly, to secure the back photocatalytic cell 130 in place, one embodiment of the back slot 225 comprises two (2) substantially parallel flanges 240, 245, which allow the back photocatalytic cell 130 to slide between the flanges 240, 245. Again, the distance between the flanges 240, 245 is approximately the same (within a desired tolerance) as the width of the back photocatalytic cell 130.
Significantly, the non-planar surface 225 is a reflective surface that allows the UV rays to be reflected at different angles (as compared to a flat, planar surface), thereby permitting a greater interaction between the UV rays and the photocatalytic cells 120, 130. This increased interaction correspondingly increases the concentration of ionized molecules, thereby improving the effectiveness of the photocatalytic system 100. For some embodiments, there has been an approximate doubling of the output of ionized molecules with almost negligible ozone production, which is a surprisingly remarkable result than one would normally predict.
Specifically, in one preferred embodiment, the non-planar reflective surface 225 comprises an angled surface, which can be produced by positioning two (2) angled protrusions 250, 255 between the front slot 215 and the back slot 220. As one can appreciate, the number of angled protrusions can be decreased (to one) or increased (to three or more), depending on how many different reflective angles are desired. For other preferred embodiments, the non-planar reflective surface 225 comprises a curved surface (not shown), thereby producing continuously varying angles of reflection. For yet other embodiments, a combination of an angled surface and a curved surface is provided, thereby allowing for a methodically controlled array of reflective angles, which can be custom-tailored to increase UV ray interaction with the photocatalytic cells 120, 130.
Turning to
It should be appreciated that the salient point is that a non-planar reflective surface 225 is provided, which results in a surprising increase in ionization, as compared to conventional systems. Specifically, a catalyst (such as the titanium in the metal oxide) with an appropriate band gap energy allows adsorption of a UV photon to generate electron hole pairs, which initiate a chemical change. For air that is partially or fully saturated with water vapor, the metal oxide surface adsorbs the water vapor to form a partially hydroxylated surface. When exposed to UV energy, the partially hydroxylated surface releases the water vapor in the form of a proton (H) and a hydroxyl (OH (or hydrogen peroxide H2O2)), which serve as disinfecting agents within the photocatalytic system 100. Thus, as shown in
Effectiveness of the photocatalytic system 100 was measured for the embodiment in which the non-planar reflective surface 225 had two (2) angled protrusions 250, 255. Specifically, each angled protrusion 250, 255 had substantially the same surface area on each side of the angle, with the angle being substantially a right angle (namely, approximately ninety degrees (~90°)). In other words, each side of each protrusion 250, 255 was: (a) symmetric about the apex; (b) formed an angle of ~135° with the reflective surface 225; and (c) met at the substantially right-angled apex. This embodiment (with two (2) angled protrusions) produced remarkably better results than expected, as compared to previously published designs by others. To confirm the unexpected results, the effectiveness was measured repeatedly and the average of the measured results were recorded.
Based on the measurements, the two-angled-protrusions embodiment was thirty percent (30%) more effective than a large, single-angled-protrusion side-wall embodiment, such as that shown in U.S. Pat. Number 9,867,897. When tested against other single-angled-protrusion side-walls, the disclosed two-angled-protrusions embodiment was shown to be seventy-three percent (73%) more effective.
As appreciated by those having skill in the art, these are remarkably better results than expected because, typically, improvements in effectiveness of photocatalytic systems are in the single-digit percentages (and not as high as 73%).
Any process descriptions or blocks in flow charts should be understood as being performed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present disclosure.
Although exemplary embodiments have been shown and described, it will be clear to those of ordinary skill in the art that a number of changes, modifications, or alterations to the disclosure as described may be made. All such changes, modifications, and alterations should therefore be seen as within the scope of the disclosure.
This application claims the benefit of U.S. Provisional Pat. Application serial number 63/271,352, filed 2021-October-25, by Randy A. Mount, having the title “Device for Reducing Airborne Contaminants,” which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63271357 | Oct 2021 | US |
