JP2022154599A - Chlorine bypass facility, cement clinker production device, cement clinker production method, operation method of chlorine bypass facility and waste treatment method - Google Patents

Abstract

To provide a technique capable of transporting coarse powder and enhancing a freedom degree of an installation position of a classification part.SOLUTION: A chlorine bypass facility 90 comprises: an extraction hole 21A for extracting a kiln exhaust gas, from a furnace tail 52 of a cement kiln 50, a rising duct 42 or a space therebetween; a classifying part 22 for separating coarse powder of raw material dust from the extracted gas extracted through the extraction hole 21A, and acquiring a derivation gas having a temperature of 770°C or greater and including fine powder of the raw material dust; and a mixing part 30 for mixing, coarse powder separated by the classifying part 22 and moisture-containing waste W.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present disclosure relates to a chlorine bypass facility, a cement clinker manufacturing apparatus, a cement clinker manufacturing method, a chlorine bypass facility operating method, and a waste disposal method.

Efforts are being made to use various types of waste as raw materials and thermal energy sources in cement clinker manufacturing equipment. Under these circumstances, the amount of chlorine brought into cement kilns tends to increase. Chlorine bypass equipment is installed in many cement clinker manufacturing equipment to reduce chlorine in the cement kiln, and technology to efficiently remove chlorine from the gas extracted by this chlorine bypass equipment has been studied. there is In Patent Document 1, coarse powder is separated from the extracted gas by a classifier while the temperature of the extracted gas extracted from the kiln exhaust gas channel is maintained at 770° C. or higher, and then cooled to 600° C. or lower to remove chlorine bypass dust. Technologies for separation have been proposed. Moreover, in Patent Document 1, it is shown that the separated coarse powder is returned to the cement kiln system.

Japanese Patent Application Laid-Open No. 2019-55900

By the way, since the coarse powder classified from the extracted gas whose temperature is maintained at 770° C. or higher is very high temperature dust, there is a problem that it is difficult to handle. Specifically, since there is no mechanical or pneumatic transport capable of transporting coarse powder that can reach temperatures of the order of 1000° C., transportation of coarse powder is difficult. It is conceivable to return the coarse powder to the cement kiln by means of a chute or the like without using a transporter, but in this case, there are conditions for the installation position and installation angle of the chute for appropriately moving the coarse powder. Therefore, there is a problem that the restrictions on the installation location of the classifier are increased.

The present disclosure has been made in view of the above, and an object of the present disclosure is to provide a technique that enables the transportation of coarse powder and increases the degree of freedom in the installation position of the classifier.

In order to achieve the above object, the chlorine bypass facility according to one aspect of the present disclosure includes a bleed port that bleeds kiln exhaust gas from the kiln bottom of a cement kiln, a rising duct, or between these, and a bleed gas that is bled from the bleed port. A classifying section for obtaining a derived gas containing fine powder of raw material dust and having a temperature of 770° C. or higher, and mixing the coarse powder separated by the classifying section with water-containing waste. and a mixing section.

According to the chlorine bypass facility, the coarse powder separated in the classifying section is mixed with the water-containing waste in the mixing section. At this time, the high-temperature coarse powder is cooled by the water-containing waste, so that it can be transported by a transportation machine, and the degree of freedom in the installation position of the classifier is increased.

The water-containing waste may contain at least one of sludge and waste liquid. In this case, the mixture of wet waste and coarse powder becomes suitable for return to the cement kiln. In addition, by mixing high-temperature coarse powder and water-containing waste, the moisture in the water-containing waste can be volatilized, suppressing deterioration of fuel efficiency of the cement kiln. You can control the deterioration. Therefore, it is possible to suppress the operation fluctuation of the cement kiln caused by inputting the water-containing waste, and to stably treat the water-containing waste.

a cooling gas introduction unit that introduces a cooling gas into a flow path through which the derived gas discharged from the classifying unit flows; and the cooling gas introduction unit that uses the steam generated in the mixing unit as part of the cooling gas. and a steam supply unit for introducing into the steam. Clinker dust, which is made from fine powder of raw material dust, has a very small particle size and is likely to clog the bag filter and clog the flow path. Therefore, by using the steam generated in the mixing section as part of the cooling gas, the clinker dust can be coarsened, and clogging of the bag filter, the flow path, and the like can be suppressed.

The cooling gas introduction section may introduce the cooling gas so as to generate a swirling flow along the inner wall surface of the flow path. As a result, it is possible to suppress the clinker dust from adhering to the inner wall of the flow path and causing coating due to the generated swirling flow forming an air curtain.

The embodiment may further include an oxygen concentration control section that controls the oxygen concentration within the mixing section so that the oxygen concentration within the mixing section is less than the limit oxygen concentration. The mixing section is an environment where combustible gas such as methane and/or dust may exist, and there is a possibility of gas explosion or dust explosion. Therefore, by adopting the configuration having the oxygen concentration control section as described above, the oxygen concentration in the mixing section can be made less than the limit oxygen concentration, thereby preventing the occurrence of gas explosion and dust explosion.

A cement clinker manufacturing apparatus according to one aspect of the present disclosure has any of the chlorine bypass facilities described above. Since the above cement clinker production apparatus includes the above-mentioned chlorine bypass facility, it is possible to transport coarse powder and increase the degree of freedom in the installation position of the classifier.

A cement clinker manufacturing method according to one aspect of the present disclosure manufactures cement clinker using the cement clinker manufacturing apparatus described above. In the method for producing cement clinker described above, since cement clinker is produced using the chlorine bypass facility described above, coarse powder can be transported and the degree of freedom in the installation position of the classifier can be increased.

A method of operating a chlorine bypass facility according to one aspect of the present disclosure includes a bleed step of obtaining kiln exhaust gas from the kiln bottom of a cement kiln, a rising duct, or between them, and raw material dust from the bleed gas obtained in the bleed step. A classifying step of separating coarse powder to obtain a derived gas having a temperature of 770° C. or higher containing fine powder of the raw material dust, and mixing the coarse powder separated in the classifying step and water-containing waste in a mixing section. and a mixing step.

According to the operating method of the chlorine bypass facility, the coarse powder separated in the classification step is mixed with the water-containing waste in the mixing section. At this time, the high-temperature coarse powder is cooled by the water-containing waste, so that it can be transported by a transportation machine, and the degree of freedom in the installation position of the classifying unit for the classifying process is increased.

A waste treatment method according to one aspect of the present disclosure is a method of treating waste with a cement clinker manufacturing apparatus, comprising a bleeding step of obtaining kiln exhaust gas from the kiln bottom of a cement kiln, a rising duct, or between them; a classification step of separating coarse raw material dust from the bled gas obtained in the bleeding step to obtain a derived gas containing fine powder of the raw material dust and having a temperature of 770° C. or higher; It includes a mixing step of mixing powder and water-containing waste in a mixing section, and a charging step of charging the mixture obtained by the mixing step into the cement kiln.

According to the waste disposal method described above, the coarse powder separated in the classification step is mixed with the water-containing waste in the mixing section. At this time, the high-temperature coarse powder is cooled by the water-containing waste, so that it can be transported by a transportation machine, and the degree of freedom in the installation position of the classifying unit for the classifying process is increased. Furthermore, by treating the waste with the cement clinker manufacturing apparatus described above, it is possible to suppress fluctuations in the operation of the cement kiln caused by the input of the water-containing waste, so that the water-containing waste can be treated stably.

ADVANTAGE OF THE INVENTION According to this disclosure, a technology is provided that makes it possible to transport coarse powder and increase the degree of freedom in the installation position of the classifier.

Drawing 1 is a figure showing chlorine bypass equipment concerning one embodiment, and a cement clinker manufacturing device provided with the same. FIG. 2 is a diagram for explaining the configuration of the coarse powder introduction section in the chlorine bypass facility. FIG. 3 is a cross-sectional view showing a radial cross-section of the flow path of the derived gas to which the cooling gas introduction part is connected.

An embodiment of the present disclosure will be described below with reference to the drawings as the case may be. However, the following embodiments are examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following contents. In the description, the same reference numerals are used for the same elements or elements having the same function, and overlapping descriptions are omitted in some cases. In addition, unless otherwise specified, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings. Furthermore, the dimensional ratio of each element is not limited to the illustrated ratio.

Drawing 1 is a figure showing chlorine bypass equipment concerning one embodiment, and a cement clinker manufacturing device provided with the same. The chlorine bypass facility 90 is connected to the rising duct 42 of the preheating and calcining section 40 of the cement clinker manufacturing apparatus 100 . The chlorine bypass facility 90 recovers volatile matter such as chlorine in the cement clinker manufacturing apparatus 100 as clinker dust to reduce the chlorine content in the cement clinker manufacturing apparatus 100 . In addition, the cement clinker manufacturing apparatus 100 may be configured including the control unit 10 .

The chlorine bypass facility 90 has a bleed port 21A that bleeds gas from the rising duct 42, and a bleed pipe 21 through which the bleed gas containing raw material dust, which is bled from the bleed port 21A, flows. In addition, the chlorine bypass equipment 90 separates the coarse powder of the raw material dust from the bled gas, and obtains a lead-out including fine powder of the raw material dust smaller than the coarse powder, the classifier 22, the channel 24 through which the lead-out gas flows, a cooling gas introduction part 80 for introducing the cooling gas so as to generate a swirling flow in the flow path 24 ; Furthermore, the chlorine bypass facility 90 has a mixing section 30 that mixes the coarse powder classified by the classifying section 22 with the water-containing waste.

The bleed gas bled from the bleed port 21A contains raw material dust and gaseous chlorine. Bleed gas flows through the bleed pipe 21 and is introduced into the classifier 22 . Bleed pipe 21 may be referred to as a bleed probe. The temperature of the bleed gas when it is introduced into the classifying section 22 is such that volatilized chlorine such as KCl and NaCl precipitates alone or precipitates on the surface of raw material dust and adheres to the classifying section 22 as clinker dust. From the viewpoint of suppression, the temperature is preferably higher than 770°C, more preferably 820°C or higher, and even more preferably 860°C or higher.

The classification unit 22 separates coarse particles of the raw material dust by introducing the extraction gas and classifying the dust. Classifying section 22 may be, for example, a cyclone. By classifying the extracted gas in the above-described temperature range in the classifying unit 22, coarse particles of the raw material dust can be separated from the extracted gas while chlorine is contained in the gas phase. Therefore, the clogging of the classifying section 22 due to the occurrence of coating due to deposition of the volatilized chlorine alone or deposition on the surface of the raw material dust is suppressed. In addition, it is possible to suppress the return of raw material dust containing chlorine to the cement kiln through the circulation passage.

From the viewpoint of suppressing the precipitation of chlorine content in the coarse powder of the raw material dust separated from the bleed gas in the classifying unit 22, the temperature of the bleed gas when separating the coarse powder of the raw material dust in the classifying unit 22 is set to 770°C. More than that. The temperature of the bleed gas can be preferably 820° C. or higher, more preferably 860° C. or higher. The temperature of the derived gas derived from the classifying section 22 is also set to 770° C. or higher. Also, the temperature of the derived gas can be preferably 820° C. or higher, more preferably 860° C. or higher.

In addition, in the classifying section 22, the exhaust gas from the combustion furnace may be mixed with the extraction gas. In this case, a mixed gas containing the extracted gas and the exhaust gas is obtained in the classification section 22 . In addition, as a combustion furnace for generating exhaust gas, for example, a combustion furnace in a waste plastic desalting facility can be mentioned. A combustion furnace is a furnace that burns tar contained in pyrolysis gas generated by heat-treating raw materials including waste plastics. When the flue gas from the combustion furnace is introduced into the classification section 22 and mixed with the extraction gas, the temperature of the mixed gas in the classification section 22 can be stably increased compared to the case of using only the extraction gas. Further, when the exhaust gas from the combustion furnace and the extraction gas are combined, the flow velocity of the mixed gas in the classification section 22 can be increased. Therefore, the classification performance in the classifying section 22 can be improved, and the coarse powder of the raw material dust can be separated from the mixed gas with higher accuracy.

The exhaust gas that joins the extraction gas in the chlorine bypass facility 90 is not limited to the exhaust gas from the combustion furnace of the waste plastic desalination facility, and may be the exhaust gas from a combustion furnace different from the combustion furnace of the waste plastic desalination facility. good. For example, as the exhaust gas, high-temperature exhaust gas from a combustion furnace, an ammonia gasification furnace, a sulfur combustion furnace, or a combustion furnace or melting furnace different from these, which is provided in the biomass pellet carbonization facility, may be used. One of these exhaust gases may be used alone, or a plurality of exhaust gases may be used in combination.

The particle size of the raw material dust coarse powder may be, for example, 18 μm or more, preferably 16 μm or more, and more preferably 14 μm or more. By classifying the raw material dust so that the coarse powder is 14 μm or more, the volatile matter can be sufficiently reduced.

Coarse powder of raw material dust separated from the extracted gas in the classifying section 22 is introduced into the mixing section 30 . The mixing section 30 is a closed container that stores coarse particles of raw material dust. Also, water-containing waste W is introduced into the mixing section 30 . Inside the mixing section 30, a stirring blade 31 for mixing the coarse powder and the water-containing waste may be provided.

Water-containing waste refers to waste having a water content of 30% or more, for example. A water content of 40% to 99% is suitable for mixing with coarse powder. Moreover, the type of waste that constitutes the water-containing waste is not particularly limited, and may be, for example, either industrial waste or general waste. Also, the water-containing waste may contain, for example, at least one of sludge and waste liquid.

The mixing ratio of the coarse powder and the water-containing waste in the mixing unit 30 is not particularly limited. You may Since the classification in the classifying section 22 is carried out in a high temperature state as described above, high-temperature coarse powder is introduced into the mixing section 30 . On the other hand, the water-containing waste is in a state containing water, and its temperature is not particularly limited, and may be normal temperature. By mixing the water-containing waste with the coarse powder, it is possible to volatilize the water content in the water-containing waste, thereby suppressing deterioration of the fuel consumption of the cement kiln. In addition, when mixed at the above ratio, the temperature of the mixture of coarse powder and water-containing waste can be lowered to, for example, 400° C. or lower compared to the coarse powder immediately after classification. As a result, the handleability of the mixture is improved. When the water-containing waste contains at least one of sludge and waste liquid, the mixture of the water-containing waste and coarse powder has properties suitable for return to the cement kiln.

In addition, in the mixing unit 30, for example, in a state in which the water-containing waste is stored in advance, the coarse powder may be dropped from the upper classifying unit 22 to mix the two in the mixing unit 30. In this case, the hot coarse powder is prevented from directly contacting the bottom surface of the mixing section 30, etc., and damage to the container can be prevented.

Further, the mixing section 30 may be provided with a sensor 35 for managing the oxygen concentration inside. The sensor 35 measures the oxygen concentration inside. A measurement result obtained by the sensor 35 is sent to the control unit 10 . Sensor 35 and control unit 10 are managed so that the oxygen concentration in mixing unit 30 is less than the limit oxygen concentration. The limit oxygen concentration used as a threshold in controlling the oxygen concentration is the "dust explosion limit oxygen concentration" and the "gas explosion limit oxygen concentration". Since water-containing waste such as sludge is used inside the mixing section 30, combustible gas such as methane is generated, and there is a risk of gas explosion. In addition, if the sludge is dried excessively by being mixed with coarse powder, there is a danger of dust explosion occurring inside the mixing section 30 . Therefore, the oxygen concentration inside is monitored so that the oxygen concentration does not reach the limit oxygen concentration at which dust explosion and/or gas explosion can occur. Thus, the sensor 35 and the control section 10 have a function as an oxygen concentration control section.

A coarse powder introducing section 23 may be provided between the classifying section 22 and the mixing section 30 as a path for introducing the coarse powder from the classifying section 22 to the mixing section 30 . FIG. 2 schematically shows the coarse powder introduction section 23. As shown in FIG. The coarse powder introduction section 23 may be configured by a pipe line formed by a vertically extending cylindrical member that connects the bottom surface of the classifying section 22 and the top surface of the mixing section 30 . In addition, two dampers 25a and 25b may be provided in the middle of the coarse powder introducing section 23. As shown in FIG. In this case, the coarse powder is introduced from the classifying section 22 into the mixing section 30 via two stages of dampers 25a and 25b. For example, the dampers 25a and 25b may be controlled by the control unit 10, or may be gravity dampers that are not controlled.

Collision members 27a and 27b may be provided below the dampers 25a and 25b, respectively, for colliding coarse particles that have passed through the dampers 25a and 25b. The shape of the collision members 27a and 27b is not particularly limited as long as they are configured to disperse coarse powder. For example, like the collision member 27a, a plurality of rod-shaped members (the cross section of the rod-shaped member is shown in FIG. 2) may be provided. Further, like the collision member 27b, an umbrella-shaped member having a diameter that increases downward from the top provided upward may be provided. Also, the collision member may be configured by combining plate-like members. In this way, the collision member may have a shape that disperses the coarse particles. If the collision member 27b is provided below the damper 25b on the downstream side, coarse powder is likely to be dispersed in the water-containing waste. On the other hand, by providing the collision member 27a above the damper 25b on the downstream side, two collision members 27a and 27b can be provided from the upstream side to the downstream side, so that coarse powder can be easily dispersed. It can be formed step by step. The arrangement and number of collision members can be changed as appropriate.

Returning to FIG. 1 , the mixture after being mixed in the mixing section 30 is introduced into the kiln bottom 52 of the cement kiln 50 because it is a raw material for cement clinker. As the passageway 29 for returning the mixture, for example, a mechanical transportation machine may be used for transportation. In this way, by returning the mixture of the raw material dust bled from the air bleed port 21A and the water-containing waste to the kiln bottom 52, it is possible to use the mixture containing the raw material dust coarse powder for the production of cement clinker. can. The mixture may be returned to the rising duct 42, the chute connecting the cyclone C4 and the kiln bottom 52, the calcining furnace 44, or the kiln main body 56 instead of the kiln bottom 52. Also, a plurality of flow paths 29 may be provided to return the mixture to a plurality of locations.

The gas discharged from the classifier 22 contains coarse powder and fine powder of raw material dust that is not collected by the classifier 22 . Further, when the exhaust gas is introduced into the classifying unit 22, the Ca component contained in the raw material dust that is not collected in the classifying unit 22 reacts with the chlorine component such as HCl in the exhaust gas to generate solid CaCl ₂ . Sometimes. Such chlorine content can also be recovered as clinker dust in the chlorine bypass facility 90 .

The derived gas containing fine powder of raw material dust and gaseous chlorine, which is obtained by separating coarse powder of raw material dust from the extracted gas in the classifying unit 22, flows through the flow path 24 connected to the classifying unit 22 and is cooled. It is cooled in the gas introduction part 80 . In the cooling gas introduction part 80, a cooling gas flow path 81 is connected to the flow path 24 formed by the circular pipe 26, and the derived gas containing the raw material dust fine powder and chlorine is mixed with the cooling gas and cooled. After cooling, the gas including the derived gas flows through the flow path 24 and is introduced into the cooling section 70 .

The cooling gas may be normal temperature air, or may include exhaust gas generated in a factory or the like at a temperature of 200° C. or less, preferably 100° C. or less. Exhaust gas includes, for example, odorous gas generated during reception, storage and fermentation of water-containing sludge such as sewage sludge brought into a cement manufacturing plant, and discharged from a suction unit 74 (see FIG. 1) described later and suction units in other processes. exhaust gas, etc. These 1 type can be used individually or in combination of 2 or more types.

As an example, FIG. 1 shows a configuration in which room-temperature air (outside air) is introduced into the cooling gas flow path 81 described above. Also, in addition to the outside air, a part of the steam generated in the mixing section 30 is introduced as a cooling gas. That is, as shown in FIG. 1, the flow path 37 for introducing the steam from the mixing section 30 is connected to the cooling gas flow path 81 for introducing outside air. The mixing section 30 is a so-called closed container. Also, the hot coarse powder is mixed with the water-containing waste to evaporate the water. As a result, steam containing moisture is generated. By introducing the steam into the flow path 81 through the flow path 37 , the outside air and the steam are mixed and introduced as the cooling gas into the cooling gas introduction section 80 . That is, the flow path 37 and the flow path 81 connected to the flow path 37 function as a steam supply section that introduces the steam generated in the mixing section 30 into the cooling gas introduction section 80 as part of the cooling gas. .

The mixing ratio of the outside air and the steam in the flow path 81 is not particularly limited. You may adjust a mixing ratio.

In the cooling gas introduction section 80, the derived gas is mixed with the cooling gas and cooled. The temperature of the gas containing the derived gas after cooling (mixed gas of the derived gas and the cooling gas) may be 600° C. or lower, or 500° C. or lower, from the viewpoint of the heat resistance of the equipment.

In the cooling gas introduction section 80, the cooling gas is introduced along the circumferential direction of the inner wall surface of the flow path 24 through which the lead-out gas containing fine powder of the raw material dust and chlorine content flows. As a result, a swirl flow is generated in the flow path 24, and it is possible to suppress the occurrence of coating due to adhesion of clinker dust to the inner wall surface of the flow path 24. Such a swirling flow forms an air curtain around the outer periphery of the flow path 24, and can protect the inner wall surface of the circular tube 26 forming the flow path 24 from the high-temperature lead-out gas.

FIG. 3 is a cross-sectional view showing a radial cross-section of the lead-out gas flow path 24 to which the cooling gas introduction part is connected. A circular pipe 26 constitutes a channel 24 through which the raw material dust coarse powder is separated and the lead-out gas containing chlorine and raw material dust fine powder flows. When viewed in a radial cross section of the flow channel 24 (circular pipe 26) as shown in FIG. It is connected to the circular tube 26 so as to extend in the direction. A cooling gas introduction part 80 connected to the circular pipe 26 introduces the cooling gas G flowing through the flow path 81 into the flow path 24 . The introduced cooling gas G forms a swirling flow SF while joining with the derived gas in the flow path 24 . The swirl axis of the swirl flow SF coincides with the central axis P of the flow path 24 formed by the circular pipe 26 .

The derived gas flows through the central portion of the flow path 24 along the axial direction of the central axis P, and the cooling gas G flows along the inner wall surface 26W of the circular tube 26 forming the flow path 24 as a swirl flow SF. In this way, in the flow path 24, the gases are circulated such that the flow paths of the derived gas and the cooling gas G are different. Although a small amount of clinker dust is generated at the boundary between the outlet gas flow path and the cooling gas G flow path, the swirling flow SF forms an air curtain to prevent the clinker dust from adhering to the inner wall surface 26W and causing coating. can be done.

As shown in FIG. 1, the chlorine bypass facility 90 includes a cooling unit 70 that cools the gas containing the derived gas downstream of the cooling gas introduction unit 80, and the dust (clinker dust) contained in the gas containing the derived gas. and a suction unit 74 for sucking the derived gas. Cooling section 70 may be a water-cooled or air-cooled heat exchanger. The suction unit 74 includes a normal suction fan such as a sirocco fan and a turbo fan.

The cooling unit 70 cools the gas including the derived gas obtained by joining the cooling gas G and the derived gas to, for example, less than 260°C, preferably less than 200°C. Since the gas containing this derived gas contains clinker dust, it is introduced into the recovery section 72 . The collection unit 72 may be a bag filter or a wet dust collector such as a wet scrubber. The clinker dust recovered by the recovery unit 72 may be mixed with a cement composition after being washed with water, or may be used as a raw material for cement.

The cement clinker manufacturing apparatus 100 of FIG. 1 includes a chlorine bypass facility 90, a preheating and calcining section 40 for preheating and calcining the cement raw material, and a cement kiln 50 for obtaining cement clinker by calcining the preheated and calcined cement raw material. and a clinker cooler 60 for cooling the cement clinker obtained in the cement kiln 50. - 特許庁The preheating and calcining section 40 has four cyclones C 1 , C 2 , C 3 , and C 4 (preheaters) and a calcining furnace 44 .

The kiln bottom 52 of the cement kiln 50 and the calcining furnace 44 of the preheating and calcining section 40 are connected by a rising duct 42 . In the vicinity of the connecting portion between the rising duct 42 and the kiln bottom 52, there is provided an air extraction port 21A of a chlorine bypass facility 90 for extracting kiln exhaust gas generated in the cement kiln 50 and recovering dust contained in the kiln exhaust gas. An air extraction pipe 21 is connected to the air extraction port 21A. The cement clinker manufacturing apparatus 100 can reduce the chlorine content in the cement clinker manufacturing apparatus 100 by including the chlorine bypass facility 90 .

The cement raw material introduced from the connection between cyclones C1 and cyclones C2 flows through cyclones C1, cyclones C2, cyclones C3, rising duct 42, calciner 44, and cyclone C4 to the kiln bottom 52 of the cement kiln 50. be introduced. In the cement kiln 50, the preheated and calcined cement raw material is heated by the combustion of the burner 54 provided on the opposite side of the kiln bottom 52 to become a cement clinker. The cement clinker obtained is cooled in a clinker cooler 60 . After cooling by the clinker cooler 60, cement clinker is obtained.

As described above, the control unit 10 functions as an oxygen concentration control unit that controls the oxygen concentration in the mixing unit 30 to be below the limit oxygen concentration based on the oxygen concentration measured by the sensor 35 . If there is a possibility that the oxygen concentration will reach or exceed the limit oxygen concentration, the control unit 10 may be configured to warn, for example, a manager or the like who manages the cement clinker manufacturing apparatus 100 . Further, when the mixing section 30 has a water spraying mechanism inside, the oxygen concentration may be lowered by spraying water inside under the control of the control section 10 . Further, when the mixing unit 30 is provided with a mechanism for introducing an inert gas such as nitrogen inside, the oxygen concentration is lowered by introducing the inert gas inside under the control of the control unit 10. may Thus, the control unit 10 functions as an oxygen concentration management unit that manages the oxygen concentration inside the mixing unit 30 .

Further, the control section 10 may control not only the mixing section 30 but also each section of the cement clinker manufacturing apparatus 100 described above. The control unit 10 may control the cement clinker manufacturing apparatus 100 based on information measured by measuring units provided in each part of the cement clinker manufacturing apparatus 100 . The operating information measured by the measurement unit includes temperature, pressure, gas component, gas flow velocity, dust concentration, image, and the like. Taking the chlorine bypass as an example, specifically, the temperature inside or on the surface of the bleed pipe 21, the classification section 22 and the flow path 24, the temperature of the kiln exhaust gas at the rising duct 42 and the bottom of the kiln 52, and the temperature from the bleed port 21A to the bleed pipe Temperature of kiln exhaust gas flowing into 21, pressure of kiln exhaust gas and bleed gas, gas components of kiln exhaust gas and bleed gas, concentration of dust contained in kiln exhaust gas and bleed gas, and images of extraction pipe 21 and classifier 22 etc. Examples of the measurement unit include temperature sensors, pressure sensors, gas component sensors, flow rate sensors, cameras, and the like.

The control unit 10 may output a control signal for adjusting the flow rate of the exhaust gas based on the operating information measured by the measuring unit. The control unit may be a normal computer system, and may include, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input/output interface, and the like.

Note that the control unit 10 may also have a function of automatically controlling the flow rate of the exhaust gas from the combustion furnace. For example, the temperature of the derived gas derived from the classifying section 22 may be measured by the measuring section, and control may be performed so that the flow rate of the exhaust gas joining the extracted gas is increased according to the measurement result. As a result, it is possible to prevent the temperature of the classifying section 22 from dropping too much.

Since the cement clinker production apparatus 100 includes the chlorine bypass facility 90, it can be operated stably, and cement clinker can be produced stably. In addition, the raw material dust can be effectively used to increase the yield of cement clinker. In addition, clinker dust is reduced, and the cost of treating clinker dust can be reduced.

[Method for producing cement clinker]
A cement clinker manufacturing method according to one embodiment can be performed using a cement clinker manufacturing apparatus 100 . These methods include a preheating and calcining step of preheating and calcining the cement raw material in the preheating and calcining unit 40, and introducing the preheated and calcined cement raw material from the kiln bottom 52 into the kiln body 56 to manufacture cement clinker. a sintering step, a sintering step of extracting the kiln exhaust gas generated in the sintering step to obtain a bleed gas, a classifying step of separating coarse powder of the raw material dust from the bleed gas containing the raw material dust in the classifying unit 22, and a classifying unit 22 A cooling gas introduction step of introducing a cooling gas so that a swirling flow is generated in a flow path through which the derived gas with reduced coarse particles of raw material dust flows, and a cooling step of cooling the gas containing the derived gas. and a dust recovery step of recovering clinker dust contained in the gas containing the derived gas cooled in the cooling step. In addition, it has a mixing step of mixing coarse powder of the raw material dust separated in the classification step with the water-containing waste in the mixing unit 30, and a charging step of returning the mixture obtained in the mixing step to the cement kiln 50 side. good too. In addition, a clinker cooling step may be included in which the cement clinker obtained in the firing step is cooled by the clinker cooler 60 .

In the preheating and calcining step, the raw material for cement is introduced from the channel between the cyclones C1 and C2. The raw material for cement is preheated through cyclones C1, C2 and C3. After that, it is introduced into the calcining furnace 44 and calcined. The calciner 44 may be provided with a burner for burning a thermal energy source such as coal. The cement raw material (calcined raw material) calcined in the calcining furnace 44 is introduced into the cyclone C4 and heated.

In the firing process, the calcined raw material heated by the cyclone C4 is introduced into the bottom 52 of the kiln. After that, it is fired in the kiln body 56 to become a cement clinker. In the air extraction process, the kiln exhaust gas generated in the firing process is extracted from the air extraction port 21A. In the classification step, coarse particles of raw material dust can be separated in a state in which chlorine is contained in the gaseous phase in the extraction gas. Therefore, it is possible to suppress the clogging of the classifying section 22 due to coating caused by deposition of volatilized chlorine alone or deposition on the surface of raw material dust. In addition, it is possible to suppress the return of the raw material dust in which chlorine is deposited to the cement kiln side through the circulation flow path.

In the mixing step, coarse powder of the raw material dust obtained in the classification step is mixed with the water-containing waste. By performing the mixing step, the temperature of the high-temperature coarse powder obtained by the classification can be lowered, so that the handleability of the mixture is improved. Moreover, by performing the circulation process of returning the mixture to the kiln bottom 52 of the cement kiln 50, the production amount of cement clinker can be increased efficiently. In addition, by mixing coarse powder and water-containing waste, the moisture in the water-containing waste can be volatilized, which can suppress the worsening of fuel consumption in the cement kiln. can be suppressed. Therefore, it is possible to suppress the operation fluctuation of the cement kiln caused by the input of the water-containing waste, so that the water-containing waste can be treated stably.

In the cooling gas introduction step, the cooling gas is joined with the derived gas derived from the classification unit 22 to cool the derived gas. At this time, as the cooling gas, steam generated in the mixing section 30 may be introduced into the cooling gas introduction section 80 as part of the cooling gas.

A swirling flow may be generated by introducing the cooling gas along the circumferential direction of the inner wall surface of the gas flow path 24 including the derived gas, which is formed by the circular tube 26 . As a result, it is possible to suppress the occurrence of coating due to adhesion of clinker dust to the flow path 24 . The temperature of the gas containing the derived gas cooled by mixing the cooling gas G in the cooling gas introduction step may be 600° C. or less, or 500° C. or less from the viewpoint of the heat resistance of the equipment. By cooling the outlet gas in this way, the volatilized chlorine is precipitated either by itself or on the surface of the raw material dust to form clinker dust.

In the cooling step, the gas including the derived gas is cooled to, for example, less than 260°C, preferably less than 200°C, in a cooling section 70 including a heat exchanger, for example. In the dust collecting step, the dust contained in the gas containing the derived gas cooled in the collecting unit 72 is collected. The dust collected in this way is called clinker dust. This manufacturing method allows the chlorine bypass facility 90 and the cement clinker manufacturing apparatus 100 to be stably operated. Moreover, the raw material dust can be effectively used to efficiently produce cement clinker. In addition, the amount of clinker dust is reduced by separating the coarse powder of the raw material dust in the classification step, and the processing cost of the clinker dust can be reduced.

[Method of operating bypass facility]
A method of operating a chlorine bypass facility according to one embodiment may include the above-described extraction step, classification step, mixing step, cooling step, and dust recovery step. Moreover, it may have the above-described charging step, or may further have any one of the steps of the above-described cement clinker manufacturing method. This operating method can be performed using a chlorine bypass facility 90 provided in the cement clinker manufacturing apparatus 100 . Therefore, the contents of each step may be the same as those in the cement clinker manufacturing method described above.

[Waste disposal method]
The cement clinker manufacturing method described above can also be called a waste disposal method. That is, the waste treatment method according to one embodiment is a method of treating waste in the above-described cement clinker manufacturing apparatus 100, and includes the above-described input step, air extraction step, classification step, mixing step, and input step. You can stay. Furthermore, it may have a cooling step and a dust recovery step. Moreover, it may further have any of the steps of the cement clinker manufacturing method described above.

[Action]
According to the above example, the coarse powder separated in the classifying section 22 is mixed with the water-containing waste W in the mixing section 30 . At this time, the high-temperature coarse powder is cooled by the water-containing waste W, so that it can be transported by a transportation machine, and the degree of freedom in the installation position of the classifier is increased.

Conventionally, it has been considered to classify the extracted gas under the condition that the derived gas having a temperature of 770° C. or more is discharged. At this time, the coarse powder obtained by classification may also be heated to a high temperature. Coarse powder obtained by classification can be returned to the preheating and calcining section 40 . However, it is difficult to transport hot coarse powder with conventional transporters. Specifically, since there is no mechanical or pneumatic transport capable of transporting coarse powder that can reach a temperature of about 1000° C., there is a problem that it is difficult to transport coarse powder. In order to solve this problem, it is conceivable to use a chute or the like to return the coarse powder to the cement kiln without using a transporter. In particular, severe conditions are imposed on the installation position and design of the classifier. In this way, there is a problem that it is difficult to design an apparatus due to the low handleability of high-temperature coarse powder after classification.

On the other hand, coarse powder is mixed with the water-containing waste W in the mixing section 30 by adopting the above configuration. The resulting mixture is cooled relative to the coarse powder, and is at a temperature that allows for transport using a transporter. Therefore, it is also possible to adopt the arrangement of the classifying section 22 in consideration of transportation using a transporter, and the degree of freedom in designing the chlorine bypass facility 90 including the classifying section 22 is increased.

Moreover, when the water-containing waste W contains at least one of sludge and waste liquid, the mixture of the water-containing waste and coarse powder has properties suitable for return to the cement kiln. In addition, by mixing high-temperature coarse powder and water-containing waste, the moisture in the water-containing waste can be volatilized, suppressing deterioration of fuel efficiency of the cement kiln. You can control the deterioration. Therefore, it is possible to suppress the operation fluctuation of the cement kiln caused by the input of the water-containing waste, so that the water-containing waste can be treated stably.

Furthermore, in the above example, the cooling gas introduction unit 80 that introduces the cooling gas into the flow path through which the derived gas discharged from the classifying unit 22 flows, and the steam generated in the mixing unit 30 are used as part of the cooling gas. A mode may further include a flow path 37 and a flow path 81 functioning as a steam supply section introduced into the cooling gas introduction section as a steam supply section. Clinker dust, which is made from fine powder of raw material dust, has a very small particle size and is likely to clog the bag filter and clog the flow path. Therefore, by using the steam generated in the mixing section as part of the cooling gas, the clinker dust can be coarsened, and clogging of the bag filter, the flow path, and the like can be suppressed.

Further, the cooling gas introduction part 80 may introduce the cooling gas so as to generate a swirling flow along the inner wall surface of the flow path. As a result, it is possible to suppress the clinker dust from adhering to the inner wall of the flow path and causing coating due to the generated swirling flow forming an air curtain.

Furthermore, the embodiment may further include a sensor 35 as an oxygen concentration management unit and the control unit 10 for managing the oxygen concentration in the mixing unit 30 so that the oxygen concentration in the mixing unit 30 reaches the limit oxygen concentration. . The mixing section 30 is an environment in which combustible gas such as methane and/or dust may exist, and a gas explosion or dust explosion may occur. Therefore, by adopting the configuration having the oxygen concentration control section as described above, the occurrence of gas explosion or dust explosion in the mixing section 30 can be prevented.

Moreover, in the above example, the cement clinker manufacturing apparatus 100 has the chlorine bypass facility 90 described above. Since the cement clinker manufacturing apparatus 100 described above includes the chlorine bypass facility 90 described above, the coarse powder can be transported, and the degree of freedom in the installation position of the classifier can be increased.

In addition, the cement clinker manufacturing method described above manufactures cement clinker using the cement clinker manufacturing apparatus 100 described above. Since the above cement clinker manufacturing method uses the chlorine bypass facility 90 described above to manufacture cement clinker, it is possible to transport coarse powder and increase the degree of freedom in the installation position of the classifier.

The operation method of the chlorine bypass facility 90 includes a bleed process for obtaining kiln exhaust gas from the kiln butt, the rising duct, or between them, separating coarse powder of raw material dust from the bleed gas obtained in the bleed process, A classifying step of obtaining a derived gas having a temperature of 770° C. or higher containing fine powder of raw material dust, and a mixing step of mixing the coarse powder separated in the classifying step and the water-containing waste in a mixing section. According to this operating method of the chlorine bypass facility, the coarse powder separated in the classification step is mixed with the water-containing waste in the mixing section. At this time, the high-temperature coarse powder is cooled by the water-containing waste, so that it can be transported by a transportation machine, and the degree of freedom in the installation position of the classifying unit for the classifying process is increased.

Further, the above-described waste treatment method is a method of treating waste by the cement clinker manufacturing apparatus 100, and includes an air extraction step for obtaining kiln exhaust gas from the kiln bottom of the cement kiln, a rising duct, or between these, and an air extraction step. A classification step of separating the coarse powder of the raw material dust from the bled gas obtained in , obtaining a derived gas containing fine powder of the raw material dust and having a temperature of 770 ° C or higher, the coarse powder separated in the classification step, and waste containing water and a mixing step of mixing materials in a mixing section, and a charging step of charging the mixture obtained by the mixing step into a cement kiln. According to the waste disposal method described above, the coarse powder separated in the classification step is mixed with the water-containing waste in the mixing section. At this time, the high-temperature coarse powder is cooled by the water-containing waste, so that it can be transported by a transportation machine, and the degree of freedom of the installation position of the classifying unit 22 for the classifying process is increased. In addition, by mixing the high-temperature coarse powder and the water-containing waste, the water content in the water-containing waste is volatilized. Draft deterioration can be suppressed. Therefore, it is possible to suppress the operation fluctuation of the cement kiln caused by the input of the water-containing waste, so that the cement clinker manufacturing apparatus 100 can stably treat the water-containing waste.

[Modification]
The disclosure herein should be considered illustrative and not restrictive in all respects. Various omissions, substitutions, modifications, etc. may be made to the above examples without departing from the scope and spirit of the claims.

Although the air bleed port 21A is provided in the rising duct 42 in the above embodiment, it is not limited to this. For example, the bleed port 21A may be provided at the kiln bottom 52, or may be provided between the kiln bottom 52 and the rising duct 42 (or at the boundary).

Further, when using the exhaust gas generated from the combustion furnace, the joining position with the extraction gas is not limited to the classifying section 22 . For example, between the classifying section 22 and the air extraction port 21A, for example, in a channel within the air extraction pipe 21, the extracted gas and the exhaust gas may join together to form a mixed gas. As another modification, the flow path of the exhaust gas may be branched so that the exhaust gas is divided into a plurality of locations and joined with the extraction gas or the mixed gas. In this case, the configuration may be such that the flow rate of the exhaust gas joining at the plurality of joining portions can be individually adjusted.

Further, in the above embodiment, the case where the control unit 10 functions as the oxygen concentration management unit to manage the oxygen concentration in consideration of the possibility of dust explosion and gas explosion in the mixing unit 30 has been described. However, instead of or in addition to this configuration, a configuration may be adopted in which the dust concentration is monitored so that the dust concentration in the mixing section 30 is less than the "explosion lower limit concentration". Further, instead of or in addition to the above configuration, a configuration may be provided in consideration of the possibility of steam explosion in the mixing section 30 .

The contents of the description of the chlorine bypass facility 90 and the cement clinker manufacturing apparatus 100 described above also apply to the description of the method of manufacturing the cement clinker and the operating method of the chlorine bypass facility described above. Further, the contents of the description of the manufacturing method and the operation method described above also apply to the description of the chlorine bypass facility 90 and the cement clinker manufacturing apparatus 100 described above.

Although several embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments. For example, in the above-described embodiment, the coarse powder of the raw material dust separated by the classifying section 22 is returned to the cement kiln 50 side through the flow path 27, but the present invention is not limited to this. For example, it may be put in a cement raw material tank and supplied to the preheating and calcining section 40 as a cement raw material. Further, the circular pipe 26 forming the flow path 24 of the derived gas may not be arranged horizontally, but may be inclined with respect to the horizontal direction. The chlorine bypass facility may have a mixing chamber between the cooling gas introduction section 80 and the cooling section 70 .

DESCRIPTION OF SYMBOLS 10... Control part 21... Bleed pipe 21A... Bleed port 22... Classification part 24... Flow path 26... Circular tube 25a, 25b... Damper 26W... Inner wall surface 27a, 27b... Collision member 28... Flow path wall 29 Flow path 30 Mixing section 31 Stirring blade 35 Sensor 37 Flow path 40 Preheating and calcining section 42 Rising duct 44 Calcination furnace 50 Cement kiln , 52... Kiln bottom 70... Cooling part 72... Recovery part 74... Suction part 80... Cooling gas introduction part 81... Flow path 90... Chlorine bypass facility 100... Cement clinker manufacturing device G... Cooling gas , SF... swirling flow, W... wet waste.

Claims (9)

a bleed port for bleed kiln exhaust gas from the kiln end of the cement kiln, the rising duct, or between these;
a classifying section for separating coarse raw material dust from the bleed gas bled from the bleed port to obtain a derived gas containing fine powder of the raw material dust and having a temperature of 770° C. or higher;
a mixing unit for mixing the coarse powder separated by the classifying unit and the water-containing waste;
, a chlorine bypass facility. 2. The chlorine bypass facility according to claim 1, wherein said wet waste includes at least one of sludge and liquid waste. a cooling gas introduction unit that introduces a cooling gas into a flow path through which the derived gas discharged from the classifying unit flows;
a steam supply unit that introduces the steam generated in the mixing unit into the cooling gas introduction unit as part of the cooling gas;
3. The chlorine bypass facility according to claim 1 or 2, further comprising: 4. The chlorine bypass facility according to claim 3, wherein said cooling gas introduction part introduces said cooling gas so as to generate a swirling flow along the inner wall surface of said flow path. The chlorine bypass facility according to any one of claims 1 to 4, further comprising an oxygen concentration management unit that manages the oxygen concentration in the mixing unit so that the oxygen concentration in the mixing unit is less than the limit oxygen concentration. A cement clinker manufacturing apparatus having the chlorine bypass facility according to any one of claims 1 to 5. A cement clinker manufacturing method, comprising manufacturing cement clinker using the cement clinker manufacturing apparatus according to claim 6 . Bleeding process for obtaining kiln exhaust gas from the kiln bottom of the cement kiln, the rising duct, or between them;
A classification step of separating coarse raw material dust from the bled gas obtained in the bled step to obtain a derived gas having a temperature of 770° C. or higher and containing fine powder of the raw material dust;
a mixing step of mixing the coarse powder separated in the classifying step and the water-containing waste in a mixing unit;
A method of operating a chlorine bypass facility, including: A method of treating waste with a cement clinker manufacturing apparatus, comprising:
Bleeding process for obtaining kiln exhaust gas from the kiln bottom of the cement kiln, the rising duct, or between them;
A classification step of separating coarse raw material dust from the bled gas obtained in the bled step to obtain a derived gas having a temperature of 770° C. or higher and containing fine powder of the raw material dust;
a mixing step of mixing the coarse powder separated in the classifying step and the water-containing waste in a mixing unit;
A step of charging the mixture obtained by the mixing step into the cement kiln;
A waste disposal method, comprising:

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