Continuous diffusion denuding with moving denuding surface

1. A method comprising:

passing a denuding gas flow along a solid denuding surface in an apparatus to concentrate one or more gas phase species from the denuding gas flow onto the denuding surface with a diffusion denuding action;

moving the denuding surface relative to one or more other portions of the apparatus that border the denuding gas flow, while continuing to concentrate the one or more gas phase species from the denuding gas flow onto the denuding surface; and

while moving the denuding surface and continuing to concentrate the one or more gas phase species from the denuding gas flow onto the denuding surface, continuously sensing quantities of at least one of the one or more gas phase species concentrated on the denuding surface.

2. The method of claim 1 , wherein the one or more gas phase species comprises a species selected from a group consisting of mercury, hydrochloric acid, and combinations thereof.

3. The method of claim 1 , wherein the denuding surface comprises a continuous surface and the method further comprises refreshing one or more denuding properties of the denuding surface while concentrating the one or more gas phase species from the gas flow onto the denuding surface, refreshing the one or more denuding properties comprising moving the denuding surface through a treatment zone that is different from a denuding zone where the one or more gas phase species is concentrated onto the denuding surface.

4. The method of claim 1 , wherein the method further comprises quantifying quantities of at least one of the one or more gas phase species.

5. The method of claim 4 , further comprising:

receiving data resulting from the sensing and quantifying;

processing the data; and

reporting results of the processing.

6. The method of claim 1 , wherein the denuding surface is a surface of a flexible sheet.

7. The method of claim 1 , wherein the denuding surface is oriented vertically while concentrating the one or more gas phase species from the gas flow onto the denuding surface.

8. The method of claim 1 , wherein the denuding gas flow is a portion of a main gas flow, and wherein the method further comprises redirecting the denuding gas flow from the main gas flow.

9. The method of claim 8 , wherein the denuding gas flow is a portion of a slip gas flow that is a portion of the main flow, and wherein redirecting the denuding gas flow from the main gas flow comprises redirecting the slip gas flow from the main gas flow and redirecting the denuding gas flow from the slip gas flow.

10. The method of claim 1 , wherein the denuding surface is a surface of a reactive coating on a substrate.

11. A method comprising:

redirecting a slip gas flow from a main gas flow, the slip gas flow being a portion of the main gas flow;

redirecting a denuding gas flow from the slip gas flow, the denuding gas flow being a portion of the slip gas flow;

passing the denuding gas flow along a denuding surface of a reactive coating on a flexible sheet in an apparatus to concentrate one or more gas phase species from the denuding gas flow onto the denuding surface with a diffusion denuding action;

moving the denuding surface relative to one or more other portions of the apparatus that border the denuding gas flow while concentrating the one or more gas phase species from the denuding gas flow onto the denuding surface;

during the moving of the denuding surface and the passing of the denuding gas flow to concentrate the one or more as phase species, continuously sensing quantities of at least one of the one or more gas phase species;

quantifying the sensed quantities of the at least one of the one or more gas phase species;

receiving data resulting from the sensing and quantifying;

processing the data; and

reporting results of the processing.

12. The method of claim 11 , wherein the denuding surface is vertically oriented.

13. The method of claim 1 , wherein a velocity of the denuding gas flow as the denuding gas flow is passed along the denuding surface is greater than a velocity of the denuding surface as the denuding gas flow is passed along the denuding surface.

14. The method of claim 13 , wherein the velocity of the denuding gas flow is from one hundred to one million times faster than the velocity of the denuding surface.

15. The method of claim 11 , wherein a velocity of the denuding gas flow as the denuding gas flow is passed along the denuding surface is greater than a velocity of the denuding surface as the denuding gas flow is passed along the denuding surface.