JP2011194290A - Denitration catalyst performance testing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a denitration catalyst performance testing apparatus which can evaluate actual catalyst performance.SOLUTION: The denitration catalyst performance testing apparatus includes a supporting member 210 consisting of a hollow structure, and plate-like denitration catalyst layers 220A-220D provided inside the supporting member 210 and supporting a denitration catalyst. The denitration catalyst layers 220A-220D are juxtaposed orthogonally to the opening surface of the supporting member 210, and closing members 230 made of a material which poisons the denitration catalyst and does not react with components in a mixed gas are provided between the denitration catalyst layer 220A and the supporting member 210 and between the denitration catalyst layer 220D and the supporting member 210.

Description

  The present invention relates to a denitration catalyst performance test apparatus for evaluating the performance of a catalyst used when denitrating nitrogen oxides in exhaust gas from a boiler or an incinerator.

Conventionally, in order to denitrate nitrogen oxides (NO _x ) from exhaust gas from boilers, combustion furnaces, etc., a reducing agent such as ammonia gas is injected into the exhaust gas to mix the exhaust gas and ammonia gas, and the mixed gas A denitration apparatus that reduces nitrogen gas and water vapor by bringing the catalyst into contact with a denitration catalyst has been used (see Patent Document 1). And the development of the denitration catalyst used for this denitration apparatus is continued for the purpose of the further improvement of the denitration capability.

  In the denitration apparatus, a honeycomb type or a plate type denitration catalyst is used, and in order to test the performance of these denitration catalysts, a denitration catalyst performance test apparatus is used. A denitration catalyst performance test device generates gas with the same components as exhaust gas from boilers, combustion furnaces, etc., raises the gas to almost the same temperature as exhaust gas from boilers, combustion furnaces, etc., and then mixes it with ammonia gas. In this apparatus, the mixed gas is passed through a test denitration catalyst for testing, and the performance of the denitration catalyst is evaluated. In such a denitration catalyst performance test apparatus, the AV value (gas processing amount per unit surface area of catalyst), SV value (gas processing amount per unit volume of catalyst), etc. are combined with the actual apparatus, which is much smaller than the actual apparatus. With the denitration catalyst, the performance of the denitration catalyst can be evaluated.

JP-A-5-163933

  However, the conventional denitration catalyst test equipment does not match the contact time of the catalyst and exhaust gas, that is, the gas flow rate flowing over the catalyst, even though the catalyst used in the actual machine has a difference in performance depending on the position. However, there is a problem that the performance of the actual denitration catalyst in the actual machine cannot be evaluated because the conditions such as the ratio of the denitration catalyst in the gas flow path are different from those of the actual machine. For this reason, what can evaluate the catalyst performance in an actual machine is calculated | required.

  In view of the circumstances described above, an object of the present invention is to provide a denitration catalyst performance test apparatus capable of evaluating actual catalyst performance.

  A first aspect of the present invention that solves the above problem is a denitration catalyst that tests the performance of a denitration catalyst that contacts a mixed gas in which exhaust gas and reducing gas are mixed to decompose nitrogen oxides contained in the exhaust gas. A performance test apparatus, comprising: a holding member made of a hollow structure; and a plate-like denitration catalyst layer provided in the holding member and supporting a denitration catalyst, wherein the denitration catalyst layer is formed of the holding member. It is arranged side by side so as to be orthogonal to the opening surface, between the denitration catalyst layer of the layer on one end side in the juxtaposition direction and the holding member, and between the denitration catalyst layer on the other end side and the holding member, In the denitration catalyst performance test apparatus, a blocking member made of a material that poisons the denitration catalyst and does not react with components in the mixed gas is provided.

  In such a first aspect, by providing a blocking member made of a material that poisons the denitration catalyst and does not react with components in the mixed gas, the surface of the denitration catalyst layer on the outer side in the juxtaposed direction is deactivated, and each gas The surface area of the denitration catalyst can be made uniform in the flow path. Thereby, the contact probability between the denitration catalyst and the gas can be easily made substantially the same as the actual machine, and the actual catalyst performance can be evaluated.

  According to a second aspect of the present invention, there is provided the denitration catalyst performance test apparatus according to the first aspect, wherein the closing member is made of anhydrous gypsum.

  In the second aspect, the blocking member does not poison the denitration catalyst and does not react with the components in the exhaust gas, and does not itself undergo thermal decomposition in the temperature range of 300 to 500 ° C. of the denitration reaction. , Gas can be reliably shut off. Thereby, actual catalyst performance can be evaluated more accurately. Further, such a blocking member can be reused, and a denitration catalyst performance test can be performed at a low cost.

  According to a third aspect of the present invention, in the denitration catalyst performance test apparatus according to the first aspect or the second aspect, a fixing member made of a heat resistant material is provided on the base end side of the closing member. It exists in the denitration catalyst performance testing apparatus characterized by being characterized.

  In the third aspect, the closing member can be reliably fixed, and the actual catalyst performance can be more reliably evaluated.

  According to a fourth aspect of the present invention, there is provided the denitration catalyst performance test apparatus according to the third aspect, wherein the fixing member is made of glass wool, silica wool, or ceramic wool. .

  In the fourth aspect, the closing member can be easily fixed, and can be closed in accordance with the shape of the end face of the denitration catalyst layer, so that the actual catalyst performance can be evaluated more reliably.

  A fifth aspect of the present invention is a denitration catalyst performance test apparatus according to any one of the first to fourth aspects, wherein the holding member is made of quartz.

  In the fifth aspect, the holding member is excellent in heat resistance, and the actual catalyst performance can be more reliably evaluated.

  According to the denitration catalyst performance test apparatus of the present invention, the surface of the denitration catalyst layer on the outer side in the juxtaposed direction is lost by providing a blocking member made of a material that poisons the denitration catalyst and does not react with the components in the mixed gas. Thus, it is possible to provide a denitration catalyst performance test apparatus that can make the surface area of the denitration catalyst uniform in each gas flow path and can evaluate the actual catalyst performance.

1 is a schematic system diagram of a denitration catalyst performance test apparatus according to Embodiment 1. FIG. 1 is a schematic cross-sectional view and a schematic vertical cross-sectional view of a denitration catalyst performance test apparatus according to Embodiment 1. FIG.

  Hereinafter, modes for carrying out the present invention will be described. The description of the present embodiment is an exemplification, and the present invention is not limited to the following description.

(Embodiment 1)
FIG. 1 is a schematic system diagram of a denitration catalyst performance test apparatus according to Embodiment 1 of the present invention. As shown in FIG. 1, a denitration catalyst performance test apparatus 1 according to this embodiment includes a gas production unit 10 that can produce a gas having the same component as the exhaust gas of a combustion apparatus such as a boiler. The gas production unit 10 is not particularly limited as long as it can produce a gas having the same component as the exhaust gas of a combustion apparatus such as a boiler. For example, NO _X , SO _X , CO, CO ₂ , O _2, etc. Examples of the apparatus include a tank that stores each component gas, extracts a predetermined amount of the component gas from the tank, and mixes and discharges the gas.

The gas production unit 10 is connected to the test unit 20, and the gas produced by the gas production unit 10 is sent to the test unit 20. The test unit 20 includes a heating device that heats a gas, an ammonia injection device, and a denitration catalyst performance tester 200 (see FIG. 2) that tests the denitration performance, which will be described in detail later. The temperature of the gas sent from the production unit 10 is raised to substantially the same temperature (about 360 ° C.) as that of a combustion apparatus such as a boiler, and then mixed with ammonia gas, which is a reducing gas, and the mixed gas is denitrated catalyst performance tester 200. A NOx removal test for decomposing NO _X in the mixed gas is performed by contacting with the catalyst, and the processed gas after the test can be discharged.

The test unit 20 is connected to the analysis unit 30, and the test unit 20 collects the processing gas after the denitration test and can analyze the denitration performance by comparing with the data of the introduced mixed gas. Yes. The analysis unit 30 is not particularly limited as long as it can collect the processing gas in the test unit 20 and analyze the denitration performance. For example, the amount of NO _{X in} the mixed gas before contacting the catalyst and the amount of NH _3, etc. from the amount and the amount of NH ₃ of the NO _X in the processing gas after contact with the catalyst apparatus for analyzing denitration performance of the catalyst and the like.

  Further, the test unit 20 is connected to the cooling unit 40. The cooling unit 40 includes a cooler that cools the processing gas discharged from the test unit 20, and a cooling water supply device that supplies cooling water used for the cooler, and is discharged from the test unit 20. The treated gas can be cooled and released to the atmosphere.

  By using such a denitration catalyst performance test apparatus 1, a gas having the same component as the exhaust gas of a combustion apparatus such as a boiler is produced, and the temperature of the gas is increased to substantially the same temperature (about 360 ° C.) as the combustion apparatus. , Mixed with ammonia gas, contact the mixed gas with the catalyst, test the denitration performance of the catalyst, analyze the results, and cool the process gas discharged after the test and release it to the atmosphere can do.

  Next, a denitration catalyst performance tester constituting the test unit 20 according to the present embodiment will be described in detail with reference to FIG. FIG. 2A is a schematic cross-sectional view showing a denitration catalyst performance test apparatus according to this embodiment, and FIG. 2B is a schematic longitudinal cross-sectional view showing a denitration catalyst performance test apparatus according to this embodiment.

  As shown in FIG. 2, a denitration catalyst performance tester 200 according to this embodiment includes a holding member 210 made of a hollow structure, and a plate-like denitration catalyst layer 220A that is provided in the holding member 210 and carries the denitration catalyst. ~ 220D.

  The holding member 210 of the present embodiment is formed of a substantially square columnar hollow structure. In other words, the holding member 210 has a substantially square columnar hollow portion at the center. Although the size of the holding member 210 is not particularly limited, the length of the hollow portion and the opening are set so that the contact probability between the denitration catalyst and the gas of the denitration catalyst performance tester 200 is substantially the same as that of the actual machine. The area has been adjusted. In the present embodiment, since the holding member 210 is made of quartz and has excellent heat resistance, changes such as deformation and alteration do not occur even under test conditions (for example, 400 ° C.).

  Although not shown, an upstream side of the holding member 210 is provided with an introduction pipe for introducing the above-described mixed gas, and a downstream side of the holding member 210 is provided with a discharge pipe for exhausting the gas after the test to the analysis unit 30. Yes. A plurality of grooves (not shown) are provided on the inner peripheral surface of the holding member 210 so as to be orthogonal to the opening surface, and a plurality of denitration catalyst layers can be fitted.

In the holding member 210, four denitration catalyst layers 220 </ b> A to 220 </ b> D are arranged in parallel at equal intervals so as to be orthogonal to the opening surface of the holding member 210. Each of the denitration catalyst layers 220A to 220D is a plate type and carries a catalyst on both sides, and such a catalyst decomposes NO _X in the mixed gas. The type of catalyst for the denitration catalyst layers 220A to 220D is not particularly limited, but in general, TiO ₂ is used as a carrier, V ₂ O ₅ is used as an active component, and WO ₃ or MoO ₃ is used as a promoter component. May be in. The intervals between the denitration catalyst layers 220A to 220D are appropriately adjusted according to the contact probability between the actual denitration catalyst and the gas.

  A blocking member 230 is provided between the denitration catalyst layer 220 </ b> A on one end side in the juxtaposed direction and the holding member 210, and between the denitration catalyst layer 220 </ b> D on the other end side and the holding member 210. .

Here, the closing member 230 is made of a material that poisons the denitration catalyst and does not react with components in the mixed gas. The material that does not react with the components in the mixed gas here refers to a material that does not adsorb, exchange, or release due to a chemical reaction with sulfur dioxide (SO ₂ ) or ammonia (NH ₃ ) in the mixed gas. Point to. Since the upper surface of the denitration catalyst layer 220A and the lower surface of the denitration catalyst layer 220D are blocked by the closing member 230, the catalyst is poisoned and does not exhibit catalytic activity. By being blocked by the blocking member 230, the permeation of the mixed gas can be inhibited, and even if the mixed gas permeates the upper surface side of the denitration catalyst layer 220A or the lower surface side of the denitration catalyst layer 220D, the mixed gas is mixed. It is possible to prevent the occurrence of errors in the measurement of the denitration performance without decomposing NO _X in the gas. Further, in the measurement of the denitration performance, no error occurs due to adsorption, exchange, release, etc. due to chemical reaction with the components in the mixed gas. That is, the denitration catalyst performance tester 200 according to the present embodiment poisons the denitration catalyst between the denitration catalyst layer 220A and the holding member 210 and between the denitration catalyst layer 220D and the holding member 210, and in the mixed gas. By providing the closing member 230 made of a material that does not react with any of the components, an error factor in measuring the denitration performance is eliminated, and the denitration performance can be accurately evaluated.

  Moreover, it is preferable that the closure member 230 is a thing with high heat resistance, and specifically, it is preferable that it does not produce a chemical and physical change in 300-500 degreeC.

As a material of the closing member 230, for example, anhydrous gypsum (CaSO ₄ ) is suitable. Anhydrous gypsum prevents the permeation of the mixed gas, and since it is a poisoning component of the denitration catalyst, even if some gas flows into the anhydrous gypsum part, it can inhibit the reaction, and it itself is chemically and physically It is preferable because it is stable and the volume does not change by heating. Furthermore, since anhydrous gypsum does not solidify and adhere to the holding member 210 made of quartz, when the closing member 230 made of anhydrous gypsum is used, both the holding member 210 and the closing member 230 can be reused. it can. The anhydrous gypsum is preferably fine powder. This is because finely powdered anhydrous gypsum can be compacted and gas can be shut off reliably.

  Further, a fixing member 240 made of a heat resistant material is provided on the base end side of the closing member 230. The fixing member 240 is provided to fix the closing member 230 at a predetermined position. The fixing member 240 is provided between the denitration catalyst layer 220A and the holding member 210 on the end side of the closing member 230 and between the denitration catalyst layer 220D and the holding member 210. It fills the gap. In FIG. 2B, only one side of the denitration catalyst performance tester 200, that is, the base end of one side of the closing member 230 is shown, but the other side not shown is similarly provided with a fixing member 240. Yes.

  Examples of the material of the fixing member 240 include glass wool, silica wool, and ceramic wool. These are excellent in heat resistance, are relatively easily fixed to the NOx removal catalyst layer 220A and the NOx removal catalyst layer 220D, and can securely fix the closing member 230. Further, the space between the denitration catalyst layer 220A and the holding member 210 and the space between the denitration catalyst layer 220D and the holding member 210 can be filled in accordance with the shapes of the end faces of the denitration catalyst layer 220A and the denitration catalyst layer 220D.

  With the configuration described above, the holding member 210 side (upper surface) of the denitration catalyst layer 220A and the holding member 210 side (lower surface) of the denitration catalyst layer 220D are not poisoned and do not exhibit catalytic activity. It has become. A space 251 sandwiched between the denitration catalyst layer 220A and the denitration catalyst layer 220B, a space 252 sandwiched between the denitration catalyst layer 220B and the denitration catalyst layer 220C, and a space 253 sandwiched between the denitration catalyst layer 220C and the denitration catalyst layer 220D. These are the gas flow paths. That is, the denitration catalyst performance tester 200 of this embodiment has three gas flow paths. The space 251, the space 252, and the space 253 that are gas flow paths have the same surface area of the denitration catalyst.

  Here, the upper and lower sides of each of the spaces 251 to 253 are denitration catalysts, that is, the mixed gas that has flowed in comes into contact with the denitration catalyst on the upper and lower sides. On the other hand, the catalyst exists only on one of the upper and lower sides between the denitration catalyst 220A and the holding member 210 on one end side in the juxtaposed direction and between the denitration catalyst layer 220D and the holding member 210 on the other end side. It is a state that does not. Therefore, if a gas flow path is provided without providing the closing member 230 between the denitration catalyst 220A and the holding member 210 and between the denitration catalyst layer 220D and the holding member 210, only one side of the gas flow path is provided. Therefore, the surface area of the gas with the denitration catalyst is halved as compared with the spaces 251 to 253. In the case of an actual machine, even if there are portions where the catalyst is present only on the upper and lower sides, the scale is large and the ratio of the whole is negligible. However, in the denitration catalyst performance tester with a very small scale, the ratio of the whole is large, and the contact probability between the denitration catalyst and the gas in the denitration catalyst performance tester 200 is greatly different from the actual machine.

  In the denitration catalyst performance tester 200 of the present embodiment, a blocking member 230 is provided between the denitration catalyst layer 220A and the holding member 210 and between the denitration catalyst layer 220D and the holding member 210, and each gas flow path ( The surface area of the denitration catalyst in the space 251, space 252, and space 253) is uniform. Thereby, in the denitration catalyst performance tester 200, the contact probability between the gas and the catalyst can be easily made substantially the same as the actual machine. Therefore, the actual catalyst performance in the actual machine can be evaluated even at a scale much smaller than that of the actual machine.

  Further, the holding member 210 side (upper surface) of the denitration catalyst layer 220A and the holding member 210 side (lower surface) of the denitration catalyst layer 220D are closed by a closing member 230 made of a material that poisons the catalyst. The surfaces of the denitration catalyst layers 220A and 220D on the outer side in the direction are deactivated. Thereby, it will be in the state blocked | interrupted without permeate | transmitting gas, and the error by permeation | transmission of gas will not arise.

  If the catalyst is not supported on the upper surface side of the denitration catalyst layer 220A or the lower surface side of the denitration catalyst layer 220D, gas permeates and an error occurs in measurement. In the present embodiment, however, the predetermined blocking member 230 described above causes an error. By closing the upper surface of the denitration catalyst layer 220A and the lower surface of the denitration catalyst layer 220D, the surfaces of the denitration catalyst layers 220A and 220D on the outer side in the side-by-side direction can be deactivated and gas permeation can be completely blocked. The actual catalyst performance in can be accurately evaluated.

  Further, as described above, in this embodiment, the holding member 210 made of quartz and the closing member 230 made of anhydrous gypsum can be reused, and a denitration catalyst performance test can be performed at a low cost.

  Here, the denitration catalyst performance tester 200, for example, makes the contact probability between the gas and the catalyst substantially the same as the actual machine by matching the space occupation rate and AP value of the denitration catalyst with the flow rate and flow rate of the gas. It can be in the state of.

  By matching the space occupancy rate of the denitration catalyst of the denitration catalyst performance tester 200 with the actual machine, the porosity of the denitration catalyst performance tester 200 can be matched with the actual machine. The porosity indicates a ratio at which the gas can flow in the cross section of the gas flow path of the denitration catalyst performance test apparatus 200, and can be obtained from the following equation. The “catalyst unit” in the following formula refers to a portion that becomes a gas flow path. In the denitration catalyst performance tester 200 of the present embodiment, a portion surrounded by the wall surface of the hollow portion of the holding member 210, the denitration catalyst layer 220A that is the uppermost layer, and 220D that is the lowermost layer is a catalyst unit.

[Formula 1]

  The AP value can be obtained from the following equation.

[Formula 2]

The above-described denitration catalyst tester 200 is configured such that the space occupation ratio and AP value of the denitration catalyst coincide with those of the actual machine, and the contact probability between the gas and the catalyst is substantially the same as that of the actual machine. Then, the flow path of the denitration catalyst tester 200 of the gas, by introducing the same flow rate, gas flow rate and actual, the NO _X in the gas mixture subjected to decompose NOx removal test, analyze the denitrification performance in the analysis section 30 By doing so, the actual catalyst performance in an actual machine can be evaluated.

  Here, a manufacturing method of the denitration catalyst tester 200 of the present embodiment will be briefly described. First, the denitration catalyst layers 220A to 220D are fitted into the holding member 210 made of quartz. After filling the material of the fixing member 240 between the denitration catalyst layer 220A and the holding member 210 and between the denitration catalyst layer 220D and the holding member 210, and filling anhydrous gypsum as the material of the closing member 230, The material of the fixing member 240 is filled again. In this embodiment, anhydrous gypsum obtained by heating hemihydrate gypsum for 2 hours in an electric furnace adjusted to 400 ° C. and then allowing it to cool is used as the material of the closing member 230.

  Hereinafter, the present invention will be described more specifically with reference to examples. In addition, this invention is not limited to a following example.

(Examples 1-3)
First, hemihydrate gypsum was heated for 2 hours in an electric furnace adjusted to 400 ° C. and then allowed to cool to obtain anhydrous gypsum.

  Denitration catalyst layers 220A to 220D were fitted to a holding member 210 made of quartz. Then, silica wool (material of the fixing member 240) is filled between the denitration catalyst layer 220 </ b> A and the holding member 210 and between the denitration catalyst layer 220 </ b> D and the holding member 210, and then the anhydrous gypsum (blocking member 230) obtained is filled. The denitration catalyst performance tester 200 of Examples 1 to 3 having the structure shown in FIG. 2 was obtained by filling silica wool (material of the fixing member 240) again. The gas flow path spacing and the catalyst layer spacing were adjusted to the values shown in Table 1.

As shown in Table 1, the denitration catalyst performance test apparatus of this embodiment adjusts the number of catalyst layers, the gas flow path interval, and the catalyst layer interval so that the space occupancy rate and AP value of the denitration catalyst are substantially the same as the actual machine. It turned out that it can be in the state of. Than this, the denitration catalyst testing apparatus of the present embodiment, by introducing the same flow rate, gas flow rate and actual, by performing the decomposing denitration tests NO _X in the gas mixture, the actual catalyst performance in actual use It was found that can be evaluated.

(Other embodiments)
In the first embodiment, the number of denitration catalyst layers is four. However, the number of denitration catalyst layers is not particularly limited as long as it is two or more, and in any case, the denitration catalyst layer on one end side of the juxtaposed direction is held. The closing member 230 may be provided between the member 210 and between the denitration catalyst layer on the other end side and the holding member.

  In addition, the outer shape of the holding member 230 is not particularly limited, and may be a cylindrical shape or the like, but preferably has a substantially square pillar-shaped hollow. This is because the volume of the gas flow path can be made substantially the same by having a substantially square columnar hollow.

1 Denitration catalyst performance test equipment
200 Denitration catalyst performance tester 210 Holding member 220A, 220B, 220C, 220D Denitration catalyst layer
230 Blocking member 240 Fixing member 251, 252, 253 Space

Claims (5)

A denitration catalyst performance test apparatus for testing the performance of a denitration catalyst that contacts a mixed gas obtained by mixing exhaust gas and a reducing gas and decomposes nitrogen oxides contained in the exhaust gas,
A holding member made of a hollow structure, and a plate-like denitration catalyst layer provided in the holding member and carrying a denitration catalyst,
The denitration catalyst layer is juxtaposed so as to be orthogonal to the opening surface of the holding member,
Between the denitration catalyst layer on one end side in the side-by-side direction and the holding member and between the denitration catalyst layer on the other end side and the holding member, the denitration catalyst is poisoned and in the mixed gas A denitration catalyst performance test apparatus characterized in that a blocking member made of a material that does not react with any of the components is provided. The denitration catalyst performance test apparatus according to claim 1, wherein the closing member is made of anhydrous gypsum. 3. The denitration catalyst performance test apparatus according to claim 1, wherein a fixing member made of a heat-resistant material is provided on a base end side of the closing member. . The denitration catalyst performance test apparatus according to claim 3, wherein the fixing member is made of glass wool, silica wool, or ceramic wool. The denitration catalyst performance test apparatus according to any one of claims 1 to 4, wherein the holding member is made of quartz.

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