JP5582414B2 - Exhaust gas cooling device - Google Patents

Description

The present invention relates to a cooling system of exhaust gas, and more particularly to a cooling apparatus of an exhaust gas discharged upon firing the cement material.

  In the cement industry, the use of industrial wastes containing various volatile impurities such as alkalis such as sodium and potassium, and chlorine, as part of the cement raw material has been promoted. This is also requested from the viewpoint of recycling. In particular, in recent years, the treatment of chlorine-containing industrial waste and the treatment of high-concentration chlorine-containing industrial waste are expected for cement production, and technology for removing chlorine from cement is desired. .

  As a technique for removing chlorine from cement, there is a technique for extracting chlorine by extracting a part of exhaust gas from a system for firing cement raw materials (for example, Patent Document 1 and Patent Document 2).

  In Patent Document 1, a probe having a double-pipe structure is communicated with a kiln exhaust gas flow path, and a part of the kiln exhaust gas is extracted through the inner pipe of the probe, and between the inner pipe and the outer pipe of the probe. In the exhaust gas cooling method in a kiln bypass for supplying cooling air to the fluid passage of the kiln bypass, the cooling air is guided inwardly at the tip of the inner tube to form a mixed quenching region at the tip of the probe. An exhaust gas cooling method is disclosed.

  Patent Document 2 discloses an extraction probe for extracting the kiln exhaust gas of the cement clinker manufacturing apparatus, a cooling chamber having a suction unit connected to the extraction probe for blowing cooling air, and the kiln exhaust gas and the cooling air from the cooling chamber. In a kiln exhaust gas bleed facility equipped with a connecting pipe for supplying air, the suction section is orthogonal to the longitudinal direction of the bleed probe, and the tangent line of the vertical section of the cooling chamber so that the cooling air forms a swirling flow A kiln exhaust gas extraction facility provided in a direction is disclosed.

JP-A-11-35355 JP 2008-239413 A

  However, in the exhaust gas cooling method in the kiln bypass disclosed in Patent Document 1, the cooling gas supplied to the outer tube of the probe is guided inward of the distal end portion of the inner tube, and the kiln exhaust gas and the cooling air are The mixed quenching zone is formed. For this reason, in the mixed quenching region at the tip of the probe, the cooling air flows in a direction opposite to the direction in which the kiln exhaust gas flows. Therefore, a part of the cooling air flows backward to the preheater side, and the temperature in the preheater decreases.

  In the cement kiln exhaust gas extraction device disclosed in Patent Document 2, the suction portion is provided so as to be orthogonal to the longitudinal direction of the extraction probe. For this reason, cooling air flows in the direction orthogonal to the direction through which kiln exhaust gas flows. Therefore, a part of the cooling air flows backward to the preheater side, and the temperature in the preheater decreases.

In view of the above problems, and aims to provide a cooling device of the exhaust gas which can suppress the drop in temperature in the preheater cools the exhaust gas.

  The exhaust gas cooling device of the present invention includes a preheater for calcining cement raw material, a kiln for calcining cement raw material calcined by the preheater, and a probe for extracting a part of exhaust gas discharged from at least one of the preheater and the kiln. And a supply unit that supplies cooling gas to the inside of the probe, and extracts the exhaust gas in the region connected to the supply unit in the probe. The angle formed between the direction extending along the direction and the direction extending toward the probe side in the supply unit is 70 degrees or less.

According to the cooling device of the exhaust gas of the present invention, the direction of extraction of the exhaust gas in the probe, the angle between the direction for supplying the cooling gas in the supply unit is not more than 70 degrees, the direction of the exhaust gas flowing through the probe It is possible to suppress the cooling gas from flowing in a direction perpendicular to and opposite to the direction. For this reason, it can suppress that cooling gas flows toward the preheater side. Therefore, the exhaust gas can be cooled while suppressing a decrease in the temperature in the preheater.

As described above, according to the present invention, it is possible to provide a cooling system of exhaust gas that can suppress the drop in temperature in the preheater cools the exhaust gas.

It is a schematic diagram which shows the cooling device of the exhaust gas in Embodiment 1 of this invention. FIG. 2 is an enlarged schematic view of a region II in FIG. FIG. 3 is an enlarged schematic diagram of a region III in FIG. 1, showing a probe and a supply unit that constitute the exhaust gas cooling device according to Embodiment 1 of the present invention. It is a figure for demonstrating the angle which the extension direction of the probe in Embodiment 1 of this invention makes and the extension direction of a supply part. FIG. 2 is an enlarged schematic diagram of a region V in FIG. 1, showing a probe and a supply unit that constitute an exhaust gas cooling device in a modification of Embodiment 1 of the present invention. It is an expansion schematic diagram which shows the probe and supply part which comprise the exhaust gas cooling device in Embodiment 2 of this invention. It is an expansion schematic diagram which shows the probe and supply part which comprise the cooling device of the waste gas in the modification of Embodiment 2 of this invention. It is a schematic diagram for demonstrating the flow of the waste gas and cooling gas in an Example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

(Embodiment 1)
First, an exhaust gas cooling apparatus according to an embodiment of the present invention will be described with reference to FIGS. The exhaust gas cooling device of the first embodiment is a device for extracting a part of the exhaust gas G1 discharged when the cement raw material is fired, and cooling the extracted exhaust gas G1.

  Specifically, as shown in FIG. 1, the exhaust gas cooling device in the present embodiment constitutes a part of a cement clinker manufacturing device 10 and includes a probe 16 and a cooling gas supply unit 17. The clinker manufacturing apparatus 10 includes a raw material supply unit 11, a preheater 12, a rising duct 13, a kiln 14, a cooling unit 15, a probe 16, a cooling gas supply unit 17, and a solid gas separation unit 18. Yes.

  The raw material supply unit 11 can store the cement raw material M and supplies the cement raw material M to the kiln 14 via the preheater 12.

  The raw material supply unit 11 is connected to a preheater 12 (moving unit PM in the present embodiment). The preheater 12 is a new suspension preheater in which a plurality of cyclones are connected in multiple stages, and includes cyclones 12a to 12d, a calcining furnace 12e, and moving parts PM and PG1, as shown in FIG.

  The moving unit PM mainly moves the cement raw material M to the cyclones 12a to 12d and the calcining furnace 12e, the raw material supply unit 11 and the cyclone 12a, the cyclone 12a and the cyclone 12b, the cyclone 12b and the cyclone 12c, The cyclone 12c and the calcining furnace 12e, the calcining furnace 12e and the cyclone 12d, and the cyclone 12d and the rising duct 13 are connected.

  The moving unit PG1 mainly moves the exhaust gas G1 to the calcining furnace 12e and the cyclones 12d to 12a. The cyclone 12c and the cyclone 12b are connected to the cyclone 12b and the cyclone 12a.

  The cyclones 12a to 12c are moved by the moving part PG1, and exchange heat between the exhaust gas G1 discharged from the calcining furnace 12e and the kiln 14 described later and the cement raw material M moved by the moving part PM. The cyclone 12d separates the exhaust gas G1 discharged from the calcining furnace 12e and the kiln 14 described later and the cement material M calcined in the calcining furnace 12e.

  The calcining furnace 12e calcines the cement raw material M heated by the cyclones 12a to 12c at a predetermined temperature. The predetermined temperature is, for example, 800 ° C. or higher and 1000 ° C. or lower. The calcining furnace 12e supplies exhaust gas G1 discharged from a kiln 14 described later to the cyclone 12d via the rising duct 13.

  As shown in FIGS. 1 and 2, the rising duct 13 includes a moving part PM connected to the cyclone 12d, a moving part PG1 connected to the calcining furnace 12e, a kiln 14 via a kiln butt 30, and a probe. 16 is connected. Inside the rising duct 13, the cement raw material M and the exhaust gas G <b> 1 pass.

  The kiln 14 fires the cement raw material M calcined in the calcining furnace 12e. A burner 14 a for ejecting fuel is disposed in the kiln 14. The kiln 14 can be heated to, for example, 1300 ° C. or more and 1500 ° C. or less. Cement clinker C can be produced by firing the cement raw material M with the kiln 14.

  The cooling unit 15 cools the cement raw material M (cement clinker C) fired in the kiln 14. The cooling unit 15 is a clinker cooler that exchanges heat between the combustion air used in the kiln 14 and the fired cement raw material M, for example.

  The probe 16 extracts a part of the exhaust gas G1 discharged from at least one of the preheater 12 and the kiln 14. The probe 16 of the present embodiment bleeds a part of the exhaust gas G1 discharged from the kiln 14 through the rising duct 13. Here, the mounting position of the probe 16 is the rising duct 13, but the mounting position is not particularly limited, and may be a kiln butt 30, for example.

  As shown in FIGS. 1 and 3, the cooling gas supply unit 17 is connected to the probe 16 in a manner inclined toward the direction of extracting the exhaust gas G <b> 1 (left direction in FIG. 3), and to the inside of the probe 16. A cooling gas G2 is supplied. In other words, it is connected to the probe 16 in an inclined manner toward the direction opposite to the preheater 12 and the kiln 14 (left side in FIGS. 1 and 3), and the cooling gas G2 is supplied into the probe 16. In other words, the cooling gas supply unit 17 is inclined in a direction toward the side opposite to the side where the preheater 12 and the kiln 14 are arranged in the extending direction of the probe 16.

  As shown in FIGS. 1, 3, and 4, the direction x (the extending direction x of the probe 16) extending along the direction (supply direction) of extracting the exhaust gas G <b> 1 in the probe 16, and the cooling gas supply unit 17, the angle θ formed by the direction y extending in the direction toward the probe 16 (the extending direction y of the cooling gas supply unit 17) is 70 degrees or less. The extending direction x of the probe 16 is a direction extending along the direction in which the exhaust gas G1 is extracted in the region of the probe 16 connected to the cooling gas supply unit 17.

  If the angle θ is expressed in another way, the direction x extending toward the side opposite to the preheater 12 and the kiln 14 (the left side in FIGS. 1, 3, and 4) in the connection region of the probe 16 with the cooling gas supply unit 17. And the angle θ formed by the direction y extending toward the probe 16 side (the upper side in FIGS. 1, 3, and 4) in the cooling gas supply unit 17. Furthermore, in other words, the angle θ formed by the extraction direction of the exhaust gas G1 and the supply direction of the cooling gas G2 is 70 degrees or less.

  When the angle θ is 90 degrees, the probe 16 and the cooling gas supply unit 17 are connected in a manner orthogonal to each other. When the angle θ exceeds 90 degrees, the cooling gas supply unit 17 is connected to the probe 16 in such a manner that the cooling gas supply unit 17 is inclined in the direction opposite to the extraction direction of the exhaust gas G1.

The angle θ is 70 degrees or less, preferably 20 degrees or more and 60 degrees or less, and more preferably 30 degrees or more and 50 degrees or less. When the angle θ is 70 degrees or less, as shown in FIG. 3, the direction in which the cooling gas G2 is supplied is not orthogonal to or opposite to the direction in which the exhaust gas G1 is extracted, so that the cooling gas G2 flows backward to the exhaust gas G1. Can be suppressed. For this reason, since it can suppress that the cooling gas G2 flows into the preheater 12 and the kiln 14, the fall of the temperature in the preheater 12 can be suppressed and the waste gas G1 can be cooled. When angle (theta) is 60 degrees or less, it can suppress more that the cooling gas G2 flows back into the waste gas G1. When angle (theta) is 50 degrees or less, it can suppress more effectively that the cooling gas G2 flows back into the waste gas G1.
On the other hand, when the angle θ is 20 degrees or more, the cooling gas G2 can be mixed with the exhaust gas G1 with higher uniformity, so that the cooling effect of the exhaust gas G1 can be enhanced by increasing the uniformity of the cooling performance of the exhaust gas G1. . Furthermore, since the time required for sufficient mixing of the exhaust gas G1 and the cooling gas G2 can be shortened, the exhaust gas G1 can be rapidly cooled. Therefore, the exhaust gas G1 containing a volatile component has deliquescence, Can be prevented from adhering to the inside of the probe 16. Since the deposits in the probe 16 can be reduced, it is possible to suppress the narrowing of the flow paths of the exhaust gas G1 and the cooling gas G2 (mixed gas G3), thereby suppressing an increase in ventilation resistance. For this reason, the electrical load of the induction fan (for example, arrange | positioned at the exit of a solid-gas separation means) for maintaining the mixed gas G3 can also be reduced. When angle (theta) is 30 degrees or more, while being able to improve the cooling effect of exhaust gas G1, the deposit | attachment by a volatile component can be reduced more.

  In the probe 16, the exhaust gas G 1 discharged from at least one of the preheater 12 and the kiln 14 and the cooling gas supply unit 17 are supplied to the cooling gas supply unit 17 in the region opposite to the preheater 12 and the kiln 14. A mixed gas G3 mixed with the cooling gas G2 flows.

  As shown in FIG. 1, the solid-gas separation means 18 is connected to the probe 16 via a moving part PG3 that moves the mixed gas G3. The solid gas separation means 18 removes dust contained in the exhaust gas G1 constituting the mixed gas G3. The solid-gas separation means 18 is not particularly limited as long as the solid and the gas can be separated, and for example, a back filter, a cyclone, a dust chamber, and a combination thereof can be used.

  The moving part PG3 that moves the mixed gas G3 from which dust has been removed by the solid-gas separation means 18 is connected to the moving part PG1 to which the exhaust gas G1 that has been heat-exchanged by the cyclone 12a moves.

  Next, the exhaust gas cooling method in the present embodiment will be described. The exhaust gas cooling method in the present embodiment cools the exhaust gas G1 using the exhaust gas cooling device shown in FIGS.

First, the process for producing the cement raw material M into the cement clinker C will be described.
As shown in FIG. 1, the cement raw material M supplied from the raw material supply part 11 is allowed to pass through each of the cyclones 12a, 12b, and 12c via the moving part PM. At this time, the cement raw material M is heated by exchanging heat with the exhaust gas G1 in the cyclones 12a, 12b, and 12c. Furthermore, the heated cement raw material M is supplied to the calcining furnace 12e via the moving part PM, and the cement raw material M is calcined in the calcining furnace 12e. The calcined cement raw material M is passed through the cyclone 12d through the moving part PM (not shown). At this time, the calcined cement raw material M is further heated by exchanging heat with the exhaust gas G1 in the cyclone 12d. Next, the calcined cement raw material M is supplied to the kiln 14 via the moving part PM, the rising duct 13 and the kiln bottom 30. The supplied cement raw material M is baked by the kiln 14 using the burner 14a, and the cement clinker C is manufactured. The cement clinker C is cooled by the cooling unit 15. Note that most of the volatile impurities are volatilized in the high temperature region of the kiln 14 and are taken into the raw material M by the preheater 12 and circulated and concentrated.

  In this state, a part of the exhaust gas G1 discharged from at least one of the preheater 12 and the kiln 14 is extracted, and the extracted exhaust gas G1 is cooled. In the present embodiment, the exhaust gas G1 is cooled as follows.

  Note that the exhaust gas can be treated by extracting a part of the exhaust gas G1 discharged when the cement raw material M is fired and removing volatile components from the extracted exhaust gas G1.

  First, a part of the exhaust gas G1 discharged from at least one of the preheater 12 for calcining the cement material M and the kiln 14 for calcining the calcined cement material M is extracted into the probe 16. In the present embodiment, a part of the exhaust gas G1 discharged from the kiln 14 is extracted to the probe 16. The method for extracting air is not particularly limited, and for example, air can be extracted by a fan (not shown).

  At this time, as shown in FIG. 2, in the rising duct 13, the cement raw material M deposited on the bottom, the cement raw material M calcined by the preheater 12, and the exhaust gas G <b> 1 discharged from the kiln 14 are mixed. . For this reason, the exhaust gas G1 moves from the kiln 14 to the probe 16 or the preheater 12, and the cement raw material M moves from the preheater 12 to the kiln 14, whereby the dust containing the volatile impurities and the cement raw material M adhering to the bottom. D soars. Thereby, exhaust gas G1 contains dust D.

  Next, as shown in FIGS. 1, 3, and 4, the cooling gas G <b> 2 is introduced into the probe 16 from the cooling gas supply unit 17 connected to the probe 16 in an inclined manner in the direction of extracting the exhaust gas G <b> 1. Supply. In other words, the cooling gas G <b> 2 is supplied to the inside of the probe 16 from the cooling gas supply unit 17 connected to the probe 16 in a manner inclined toward the direction opposite to the preheater 12 and the kiln 14.

  In this step, as shown in FIGS. 3 and 4, the cooling gas G2 is supplied so that the angle θ formed with the direction in which the exhaust gas G1 is extracted is 70 degrees or less. That is, in this step, the cooling gas G2 is supplied so that the angle θ formed by the direction in which the exhaust gas G1 flows and the direction in which the cooling gas G2 flows is 70 degrees or less. In other words, the angle θ formed by the direction x extending toward the opposite side of the preheater 12 and the kiln 14 in the probe 16 and the direction y extending toward the probe 16 in the cooling gas supply unit 17 is 70 degrees or less. The cooling gas G2 is supplied so that When the angle θ is 90 degrees, the direction in which the exhaust gas G1 flows is orthogonal to the direction in which the cooling gas G2 flows. When the angle θ exceeds 90 degrees, the cooling gas G2 is supplied in the direction opposite to the extraction direction of the exhaust gas G1.

The angle θ is 70 degrees or less, preferably 20 degrees or more and 60 degrees or less, and more preferably 30 degrees or more and 50 degrees or less. When the angle θ is 70 degrees or less, as shown in FIG. 3, the direction in which the cooling gas G2 is supplied is not orthogonal to or opposite to the direction in which the exhaust gas G1 is extracted, so that the cooling gas G2 flows backward to the exhaust gas G1. This can be suppressed. For this reason, since it can suppress that the cooling gas G2 flows into the preheater 12 and the kiln 14, the fall of the temperature in the preheater 12 can be suppressed and the exhaust gas G1 can be cooled. When angle (theta) is 60 degrees or less, it can suppress more that the cooling gas G2 flows back into the waste gas G1. When angle (theta) is 50 degrees or less, it can suppress more effectively that the cooling gas G2 flows back into the waste gas G1.
On the other hand, when the angle θ is 20 degrees or more, the cooling gas G2 can be mixed with the exhaust gas G1 with higher uniformity, so that the cooling effect of the exhaust gas G1 can be enhanced by increasing the uniformity of the cooling performance of the exhaust gas G1. At the same time, impurities due to volatile components contained in the exhaust gas G1 can be prevented from adhering in the probe 16. When the angle θ is 30 degrees or more, the cooling effect of the exhaust gas G1 can be further increased, and deposits due to volatile components in the probe 16 can be further reduced.

  In addition, the cooling gas G2 supplied in this process is not specifically limited, For example, air etc. are used.

  In this step, by supplying the cooling gas G2 so as not to go backward with respect to the flow of the exhaust gas G1, it is possible to suppress the cooling gas G2 from flowing into the preheater 12 and the kiln 14 side. In addition, the processing method of the cooled exhaust gas (mixed gas of exhaust gas G1 and cooling gas G2) is performed as follows, for example.

  Specifically, the mixed gas G3 containing the cooled exhaust gas G1 is supplied to the solid-gas separation means 18 via the moving part PG3 as shown in FIG. In this step, the dust D (see FIG. 2) contained in the mixed gas G3 is separated by the solid gas separation means 18. The separated dust D may be discharged out of the system of the cooling device. Alternatively, the cement raw material may be further separated from the separated dust D, and the separated cement raw material may be moved to the raw material supply unit 11 and re-input.

  On the other hand, the mixed gas G3 from which the dust has been removed by the solid-gas separation means 18 is discharged out of the cooling system together with the exhaust gas G1 whose heat exchange with the cement raw material M has been completed by the cyclone 12a of the preheater 12.

(Modification)
With reference to FIG.1 and FIG.5, the cooling apparatus and cooling method of the waste gas in the modification 1 of embodiment of this invention are demonstrated. The first modification is basically the same as the first embodiment, but differs in the structure of the cooling gas supply unit 17.

  As shown in FIG. 5, the cooling gas supply part 17 which comprises the exhaust gas cooling device of the modification 1 is connected to the area | region which protruded upwards in the probe 16 in FIG. Even in this case, the cooling gas supply unit 17 is connected to the probe 16 in an inclined manner in the direction of extracting the exhaust gas G1. Further, the angle formed by the direction x extending along the direction in which the exhaust gas G1 is extracted from the probe 16 and the direction y extending toward the probe 16 in the cooling gas supply unit 17 is 70 degrees or less.

  In the cooling method of the exhaust gas G1 of the first modification, the cooling gas G2 is supplied in the second half of the exhaust gas G1 flowing inside the probe 16. Even in this case, the cooling gas G2 is supplied so that the angle formed with the direction in which the exhaust gas G1 is extracted is 70 degrees or less.

  Here, as in Modification 1, when there are a plurality of directions x extending along the direction in which the exhaust gas G1 is extracted in the probe 16, the extension of the region of the probe 16 connected to the cooling gas supply unit 17 is extended. It means direction.

  In addition, in this Embodiment and the modification, although the cooling apparatus and cooling method of the waste gas discharged | emitted from the kiln 14 were demonstrated, this invention is applicable also to the waste gas discharged | emitted from the preheater 12. FIG. That is, the present invention includes i) a cooling device and a cooling method for exhaust gas discharged from the kiln 14 and the preheater 12, ii) a cooling device and cooling method for only the exhaust gas discharged from the kiln 14, and iii) discharged from the preheater 12. Includes exhaust gas only cooling device and cooling method.

  Moreover, the exhaust gas discharged | emitted from the preheater 12 should just be the exhaust gas which passes any location of cyclones 12a-12d and the calcining furnace 12e, and exhaust gas may be extracted from one location, and it may be from several locations. The exhaust gas may be extracted.

  When exhaust gas is extracted from the preheater 12 and the kiln 14, or when exhaust gas is extracted from a plurality of locations in the preheater 12, the exhaust gas may be introduced into a plurality of probes 16 connected to the respective exhaust gases. Each exhaust gas may be introduced into one probe 16.

  As described above, the exhaust gas G1 cooling apparatus and cooling method according to the first embodiment and the modification of the present invention supplies the cooling gas G2 in the direction in which the exhaust gas G1 is extracted in the probe 16 and the cooling gas supply unit 17. The angle θ formed with the direction to be is 70 degrees or less.

  According to the exhaust gas G1 cooling device and the cooling method of the first embodiment and the modification of the present invention, the cooling gas G2 is in a direction orthogonal to and opposite to the direction of the exhaust gas G1 flowing in the probe 16 (the direction opposite to the direction x). Flow can be suppressed. That is, it is possible to suppress the cooling gas G2 from flowing into the preheater 12 and the kiln 14. Thereby, the fall of the temperature in the preheater 12 and the kiln 14 can be suppressed, and the exhaust gas G1 can be cooled.

  Thus, if the fall of the temperature in the preheater 12 and the kiln 14 can be suppressed, it can suppress that the temperature of the cement raw material M which flows through the preheater 12 and the kiln 14 falls. For this reason, the restriction | limiting with respect to the quantity of the cement raw material M supplied from the raw material supply part 11 becomes small. That is, it is not necessary to excessively reduce the amount of the cement raw material M supplied from the raw material supply unit 11. Therefore, the efficiency of manufacturing the cement clinker C from the cement raw material M can also be improved.

  Furthermore, since it is possible to suppress the cooling gas G2 from flowing in the direction opposite to the direction x extending toward the opposite side of the preheater 12 and the kiln 14 in the probe 16, most of the cooling gas G2 is used for cooling the exhaust gas G1. Can do. For this reason, according to the cooling device and the cooling method of the present embodiment, the exhaust gas G1 can be efficiently cooled without significantly increasing the amount of the cooling gas G2.

(Embodiment 2)
With reference to FIG. 6, the exhaust gas cooling device and cooling method according to Embodiment 2 of the present invention will be described.

  The present embodiment is basically the same as the first embodiment, but differs in the structure of the probe 16 and the cooling gas supply unit 17.

  As shown in FIG. 6, the probe 16 constituting the exhaust gas cooling device of the present embodiment has a part extending in the horizontal direction and a part protruding downward, and is a part of the part extending in the horizontal direction. The volume is relatively small. The cooling gas supply unit 17 is connected to a portion that is in the vicinity of the bent portion and protrudes downward.

  Even in this case, the cooling gas supply unit 17 is connected to the probe 16 in an inclined manner in the direction of extracting the exhaust gas G1. Further, a direction x extending along the direction of extracting the exhaust gas G1 in a region connected to the cooling gas supply unit 17 of the probe 16, and a direction y extending toward the probe 16 in the cooling gas supply unit 17. Is an angle of 70 degrees or less.

  In the method for cooling the exhaust gas G1 of the present embodiment, the cooling gas G2 is supplied to a region extending downward in the probe 16. Even in this case, the cooling gas G2 is supplied so that the angle formed with the direction in which the exhaust gas G1 is extracted is 70 degrees or less.

  According to the cooling apparatus and cooling method of the exhaust gas G1 in the second embodiment of the present invention, the exhaust gas G1 is cooled by suppressing the temperature drop in the preheater 12 and the kiln 14 without depending on the structure of the probe 16. be able to.

(Modification)
With reference to FIG. 7, an exhaust gas cooling device and a cooling method in a modification of the second embodiment of the present invention will be described. The modification is basically the same as that of the second embodiment, but differs in the structure of the cooling gas supply unit 17.

  As shown in FIG. 7, the cooling gas supply unit 17 constituting the exhaust gas cooling device of the modified example is connected to a region extending in the horizontal direction in the probe 16. Even in this case, the cooling gas supply unit 17 is connected to the probe 16 in an inclined manner in the direction of extracting the exhaust gas G1. Further, a direction x extending along the direction of extracting the exhaust gas G1 in a region connected to the cooling gas supply unit 17 of the probe 16, and a direction y extending toward the probe 16 in the cooling gas supply unit 17. Is an angle of 70 degrees or less.

  In the cooling method of the exhaust gas G1 of the modification, the cooling gas G2 is supplied to a region extending in the horizontal direction in the probe 16. Even in this case, the cooling gas G2 is supplied so that the angle formed with the direction in which the exhaust gas G1 is extracted is 70 degrees or less.

  According to the exhaust gas G1 cooling device and cooling method in the modification of the second embodiment of the present invention, the cooling gas G2 can be supplied to the extracted exhaust gas G1 at an early stage, so that the exhaust gas G1 is cooled more efficiently. be able to.

  In the present embodiment, the angle θ formed by the direction x extending along the direction of extracting the exhaust gas in the probe 16 and the direction y extending toward the probe 16 in the cooling gas supply unit 17 is 70 degrees or less. I investigated the effect of certain things.

(Test Examples 1 to 7)
In Test Examples 1 to 7, the exhaust gas G1 was cooled by the cooling device and the cooling method of the first embodiment shown in FIGS.

  Specifically, as shown in FIG. 3, the exhaust gas cooling device of Test Examples 1 to 7 is connected to the probe 16 in a manner inclined toward the direction opposite to the preheater 12 and the kiln 14, and the probe The cooling gas supply part 17 which supplies the cooling gas G2 to the inside of 16 was provided. A direction extending along the direction of extracting the exhaust gas in the region connected to the cooling gas supply unit 17 in the probe 16 of the test examples 1 to 7 (probe extending direction x in FIG. 4), and the cooling gas supply unit 17, the angles θ formed with the direction extending toward the probe 16 (the extending direction y of the cooling gas supply unit 17 in FIG. 4) are 20 degrees, 25 degrees, 30 degrees, 45 degrees, 50 degrees, respectively. 60 degrees and 70 degrees were set.

  Moreover, the cooling method of the waste gas of Test Examples 1-7 was performed as follows. First, a part of the exhaust gas G1 discharged from the kiln 14 was extracted into the probe 16. The temperature and air volume of the exhaust gas G1 in this step are shown in Table 1 below. In addition, each of the temperature and the air volume of the exhaust gas G1 was measured by a method according to JIS Z 8808 (measuring method of dust concentration in exhaust gas). The measurement point of the exhaust gas G1 was the entrance of the probe 16.

  Next, the cooling gas G2 is introduced into the probe 16 so that the angles θ formed with the direction of extracting the exhaust gas G1 are 20 degrees, 25 degrees, 30 degrees, 45 degrees, 50 degrees, 60 degrees, and 70 degrees, respectively. Supplied. The air volume, speed and temperature of the cooling gas in this step are shown in Table 1 below. In addition, each of the temperature and the air volume of the cooling gas G2 was measured by a method according to JIS Z 8808 (measuring method of dust concentration in exhaust gas). The measurement point of the cooling gas G2 was the supply port of the cooling gas supply unit.

(Test Examples 8 to 10)
The exhaust gas cooling device and the cooling method of Test Examples 8 to 10 were basically the same as those of Test Examples 1 to 7, but the extending direction x of the probe 16 shown in FIG. The difference was that the angles θ formed with the extending direction y were 80 degrees, 85 degrees, and 90 degrees, respectively. When the angle θ was 90 degrees, the probe 16 and the cooling gas supply unit 17 were orthogonal. In Test Examples 8 to 10, the temperature and air volume of the exhaust gas G1 to be extracted and the air volume, speed and temperature of the cooling gas G2 to be supplied are shown in Table 1 below. The measurement method was the same as in Test Examples 1-7.

(Evaluation method)
About Test Examples 1-10, as shown in FIG. 8, among the supplied cooling gas G2, the cooling gas G2-1 used for cooling the exhaust gas G1 (recovered as the mixed gas G3) is “recovered cooling gas G2”. −1 = (air volume of mixed gas G3) − (air volume of exhaust gas G1) ”. The temperature and air volume of the mixed gas G3 were also measured by a method according to JIS Z 8808 (measuring method of dust concentration in exhaust gas). Further, the measurement point of the mixed gas G3 was set at a position moved 3 m from the cooling gas supply unit in the direction in which the exhaust gas G1 flows.
Further, the cooling gas G2-2 that has flowed back (flowed out) to the preheater 12 side is calculated from the equation "flowing cooling gas G2-2 = (air volume of cooling gas G2)-(air volume of recovered cooling gas G2-1)". did. The results are listed in Table 1 below.

  Also, during the bleed operation, visual observation from the inspection port and the gas static pressure at the probe outlet were measured to confirm the increase in the amount of deposits in the probe. In addition, the measurement point of the increase state of the deposit in the probe was set to a position moved 3 m from the cooling gas supply unit in the direction in which the exhaust gas G1 flows. The results are listed in Table 1 below. In Table 1 below, “◯” means that continuous operation was possible for 4 hours or more without particularly removing the deposits, and “△” indicates that there was a tendency of clogging and several times during 4 hours. It means that the removal work was required.

(Evaluation results)
As shown in Table 1, Test Examples 1 to 7 in which the angle θ formed by the extending direction x of the probe 16 and the extending direction y of the cooling gas supply unit 17 is 70 degrees or less are shown in Table 1 below. Among these, the cooling gas G2-2 that flowed out to the preheater 12 side was 15 m ³ _N / min or less (10% or less), and it was found that the temperature drop in the preheater 12 could be suppressed. In particular, in Test Examples 1 to 6 in which the angle θ formed by the extending direction x of the probe 16 and the extending direction y of the cooling gas supply unit 17 is 60 degrees or less, of the supplied cooling gas G2 to the preheater side. In the test examples 1 to 5 in which the cooling gas G2-2 that flowed out was 7 m ³ _N / min or less (less than 5%) and the angle θ was 50 degrees or less, the cooling gas G2 that flowed out flowed to the preheater 12 side. The cooling gas G2-2 was 2 m ³ _N / min or less (less than 2%), and it was found that the temperature drop in the preheater 12 can be effectively suppressed.

  Further, as shown in Table 1, Test Examples 1 to 7 in which the angle θ formed by the extending direction x of the probe 16 and the extending direction y of the cooling gas supply unit 17 is 30 degrees or more and 70 degrees or less include the probe The deposits in 16 could be reduced.

On the other hand, in Test Examples 8 to 10 in which the angle θ formed by the extending direction x of the probe 16 and the extending direction y of the cooling gas supply unit 17 is 80 degrees or more, the precooler 12 side of the supplied cooling gas G2 is used. The cooling gas G2-2 that flowed out was 20 m ³ _N / min or more, and the temperature in the preheater 12 was lowered.

  As described above, according to the present embodiment, the angle θ formed by the extending direction x of the region connected to the cooling gas supply unit 17 in the probe 16 and the extending direction y of the cooling gas supply unit 17 is 70 degrees or less. By being, since it can suppress that the cooling gas G2 flows back to the preheater side, it has confirmed that the fall of the temperature in a preheater can be suppressed.

  As described above, the embodiments and examples of the present invention have been described, but it is also planned from the beginning to appropriately combine the features of the embodiments and examples. The embodiments and examples disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the embodiments and examples described above but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

  DESCRIPTION OF SYMBOLS 10 Manufacturing apparatus, 11 Raw material supply part, 12 Preheater, 12a-12d Cyclone, 12e Calcining furnace, 13 Rising duct, 14 Kiln, 14a Burner, 15 Cooling part, 16 Probe, 17 Cooling gas supply part, 18 Solid-gas separation means , 30 Kiln bottom, C cement clinker, D dust, M cement raw material, G1 exhaust gas, G2 cooling gas, G2-1 recovered cooling gas, G2-2 outflowing cooling gas, G3 mixed gas, PG1, PG3, PM moving part .

Claims (1)

A preheater for calcining the cement raw material;
A kiln for firing the cement raw material calcined by the preheater;
A probe for extracting a part of the exhaust gas discharged from at least one of the preheater and the kiln;
A supply unit that is connected to the probe in a manner inclined toward the direction of extracting the exhaust gas and that supplies a cooling gas to the inside of the probe;
An angle formed between a direction extending along the direction of extracting the exhaust gas in a region connected to the supply unit in the probe and a direction extending toward the probe side in the supply unit is 70 degrees or less. An exhaust gas cooling device, comprising:

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