Catalyst for reducing mercury, a mercury conversion unit, and an apparatus for measuring total mercury in combustion exhaust gas by using the same

Abstract

The present invention relates to a catalyst for reducing mercury, which comprises a reagent comprising any of the sulfites of potassium, sodium, calcium and magnesium, or any of the phosphates thereof, or a combination of them, as a main reagent of a catalyst component. And the present invention relates to the catalyst for reducing mercury, wherein the catalyst component is mixed with a different salt as an agent for inhibiting crystallization of the catalyst component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration showing temperature characteristics for efficiency of reduction with the reagent of the present invention;

FIG. 2 is an illustration showing the influence of coexistent cesium oxide (SeO₂) on the efficiency of reduction of Hg;

FIG. 3 is an illustration schematically showing the constitution of a mercury conversion unit;

FIG. 4 is an illustration schematically showing a procedure of granulating a mercury reduction catalyst using sulfite;

FIG. 5 is an illustration showing a constitution of an apparatus for measuring total mercury in exhaust gas;

FIG. 6 is an illustration showing another constitution of an apparatus for measuring total mercury in exhaust gas;

FIG. 7 is an illustration showing a constitution of a conventional method of continuously analyzing gaseous total mercury in exhaust gas; and

FIG. 8 is another illustration showing a constitution of a conventional method of continuously analyzing gaseous total mercury in exhaust gas.

Claims

1. A catalyst for reducing mercury, which comprises a reagent comprising any of the sulfites of potassium, sodium, calcium and magnesium, or any of the phosphates thereof, or a combination of them, as a main reagent of a catalyst component.

2. The catalyst for reducing mercury according to claim 1, wherein the catalyst component is mixed with a different salt as an agent for inhibiting crystallization of the catalyst component.

3. The catalyst for reducing mercury according to claim 1, wherein the catalyst component comprising the reagent as a main reagent is supported by a basic binder with an inorganic porous particle material as a carrier of the catalyst.

4. The catalyst for reducing mercury according to claim 2, wherein the catalyst component comprising the reagent as a main reagent is supported by a basic binder with an inorganic porous particle material as a carrier of the catalyst.

5. The catalyst for reducing mercury according to claim 3, wherein refractory and/or activated alumina is used as the inorganic porous particle material, and liquid glass and/or lithium silicate is used as the basic binder.

6. The catalyst for reducing mercury according to claim 4, wherein refractory and/or activated alumina is used as the inorganic porous particle material, and liquid glass and/or lithium silicate is used as the basic binder.

7. A mercury conversion unit comprising the catalyst for reducing mercury according to claim 1 charged into a predetermined container consisting of an inorganic material such as glass, quartz or ceramics or an oxidized metal such as oxidized stainless steel or titanium as a gas-contacting material wherein the operative temperature of the catalyst for reducing mercury is 300 to 500° C.

8. A mercury conversion unit comprising the catalyst for reducing mercury according to claim 2 charged into a predetermined container consisting of an inorganic material such as glass, quartz or ceramics or an oxidized metal such as oxidized stainless steel or titanium as a gas-contacting material wherein the operative temperature of the catalyst for reducing mercury is 300 to 500° C.

9. A mercury conversion unit comprising the catalyst for reducing mercury according to claim 3 charged into a predetermined container consisting of an inorganic material such as glass, quartz or ceramics or an oxidized metal such as oxidized stainless steel or titanium as a gas-contacting material wherein the operative temperature of the catalyst for reducing mercury is 300 to 500° C.

10. A mercury conversion unit comprising the catalyst for reducing mercury according to claim 4 charged into a predetermined container consisting of an inorganic material such as glass, quartz or ceramics or an oxidized metal such as oxidized stainless steel or titanium as a gas-contacting material wherein the operative temperature of the catalyst for reducing mercury is 300 to 500° C.

11. A mercury conversion unit comprising the catalyst for reducing mercury according to claim 5 charged into a predetermined container consisting of an inorganic material such as glass, quartz or ceramics or an oxidized metal such as oxidized stainless steel or titanium as a gas-contacting material wherein the operative temperature of the catalyst for reducing mercury is 300 to 500° C.

12. An apparatus for measuring total mercury using the catalyst for reducing mercury according to claim 1, which has the catalyst for reducing mercury or the mercury conversion unit in a part of a sample collection flow path, and after treatment, a sample is introduced into an ultraviolet absorption analyzer.

13. An apparatus for measuring total mercury using the catalyst for reducing mercury according to claim 2, which has the catalyst for reducing mercury or the mercury conversion unit in a part of a sample collection flow path, and after treatment, a sample is introduced into an ultraviolet absorption analyzer.

14. An apparatus for measuring total mercury using the catalyst for reducing mercury according to claim 3, which has the catalyst for reducing mercury or the mercury conversion unit in a part of a sample collection flow path, and after treatment, a sample is introduced into an ultraviolet absorption analyzer.

15. An apparatus for measuring total mercury using the catalyst for reducing mercury according to claim 4, which has the catalyst for reducing mercury or the mercury conversion unit in a part of a sample collection flow path, and after treatment, a sample is introduced into an ultraviolet absorption analyzer.

16. An apparatus for measuring total mercury using the catalyst for reducing mercury according to claim 5, which has the catalyst for reducing mercury or the mercury conversion unit in a part of a sample collection flow path, and after treatment, a sample is introduced into an ultraviolet absorption analyzer.

17. An apparatus for measuring total mercury using the mercury conversion unit according to claim 7, which has the catalyst for reducing mercury or the mercury conversion unit in a part of a sample collection flow path, and after the treatment, a sample is introduced into an ultraviolet absorption analyzer.

18. An apparatus for measuring total mercury using the mercury conversion unit according to claim 8, which has the catalyst for reducing mercury or the mercury conversion unit in a part of a sample collection flow path, and after the treatment, a sample is introduced into an ultraviolet absorption analyzer.

19. The apparatus for measuring total mercury in exhaust gas according to claim 12, wherein a mist capturing agent or a counteragent is used in a pre-stage for the catalyst for reducing mercury or the mercury conversion unit in the sample collection flow path.

20. The apparatus for measuring total mercury in exhaust gas according to claim 13, wherein a mist capturing agent or a counteragent is used in a pre-stage for the catalyst for reducing mercury or the mercury conversion unit in the sample collection flow path.