Ammonia desulfurization system

Abstract

The utility model discloses an ammonia desulfurization system which comprises a mixer, and the mixer is connected with a metering blanking pump, a metering ammonia adding pump and a centrifuge metering feeding pump through pipelines. According to the utility model, the mixer is arranged between the thickener and the centrifugal machine, and the mixer has two functions: firstly, the mixer is used as a buffer temporary storage container to receive the feed liquid from the outlet of the thickener, and secondly, the mixer is used as a mixed reaction device to provide a reaction space for the combination of ammonia water and the feed liquid. The device reduces the corrosion of the slurry to the ammonium sulfate equipment, has the advantages of simplicity and convenience in operation, safety, environment friendliness and good reliability, utilizes the existing device pipeline as much as possible, ensures that the free acid content in the ammonium sulfate product meets the standard requirement of the product at lower transformation cost, and has practical significance.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas desulfurization, in particular to an ammonia desulfurization system. Background Art

[0002] Ammonia desulfurization technology is widely used in the chemical industry. From a process perspective, the principle is to use ammonia to absorb SO in the tail gas of sulfuric acid production. 2 , producing ammonium sulfite and ammonium sulfate. During the production process, the pH value of the slurry in the desulfurization tower needs to be maintained between 5.0 and 5.9 to ensure that ammonium sulfite is oxidized to ammonium sulfate under this condition. In addition, since the boiler is mixed with low-pressure venting air to reduce costs, the free acid concentration in the ammonium sulfate product after ammonia desulfurization is too high, exceeding the standard requirements, resulting in unqualified products. In order to adjust the acidity and control the product quality, it is necessary to detect the pH of the slurry in the desulfurization tower in real time. However, in the actual process, due to the continuous production method adopted in industry, slurry is continuously produced from the desulfurization tower, so there is a certain lag in the adjustment of the slurry pH. Even if the acidity of the slurry in the desulfurization tower is found to be abnormal, the pH of the slurry in the desulfurization tower can only be adjusted. The pH of the slurry that has been output still exceeds the standard, resulting in excessive free acid concentration. In order to prevent the free acid of the ammonium sulfate product from exceeding the standard, it is necessary to improve the production process, and make the use of existing equipment pipelines as much as possible, with a relatively small transformation cost, so that the free acid content in the ammonium sulfate product meets the product standard requirements, which is of practical significance. Utility Model Content

[0003] The utility model provides an ammonia desulfurization system, which solves the problems of excessive free acid in ammonium sulfate products, unqualified ammonium sulfate products, too strong slurry acidity and corrosion of equipment pipelines.

[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0005] The first aspect of the present application provides an ammonia desulfurization system, including a mixer, which is connected to a metering feed pump, a metering ammonia pump and a centrifuge metering feed pump through a pipeline. In the production process, in order to adjust the acidity and control the product quality, it is necessary to detect the pH of the slurry in the desulfurization tower in real time. However, in the actual process, due to the continuous production method adopted in industry, slurry is continuously produced from the desulfurization tower, so there is a certain hysteresis in the adjustment of the slurry pH. Even if the acidity of the slurry in the desulfurization tower is found to be abnormal, the pH of the slurry in the desulfurization tower can only be adjusted. The pH of the output slurry still exceeds the standard, resulting in excessive free acid concentration. In this preferred embodiment, a mixer is set between the thickener and the centrifuge. The mixer has two functions. First, it serves as a buffer storage container to receive the feed liquid from the thickener outlet. Secondly, it serves as a mixing reaction device to provide a reaction space for the combination of ammonia water and feed liquid. The mixer has two inlets, one of which is connected to the metering feed pump through a pipeline to receive the incoming liquid feed, and the other inlet is connected to the metering ammonia addition pump through a pipeline to receive the incoming ammonia water. After meeting the requirements, the liquid feed is output to the centrifuge metering feed pump through a pipeline for subsequent processes.

[0006] Furthermore, the thickener is connected to the metering feed pump through a pipeline. In this preferred solution, the metering feed pump controls the feed speed to prepare for the subsequent feed liquid to enter the mixer, controls the flow rate not to exceed the maximum load of the mixer, and facilitates the subsequent detection and regulation of the acidity of the feed liquid.

[0007] Furthermore, a first acidity detector is provided between the thickener outlet and the metering feed pump. In this preferred solution, the first acidity detector monitors the acidity of the feed liquid output from the thickener in real time, so as to coordinate with the subsequent second acidity detector and the metering ammonia pump to control the acidity of the feed liquid.

[0008] Furthermore, a second acidity detector is provided in the mixer. In this preferred embodiment, the acidity of the feed liquid in the mixer is monitored in real time by the second acidity detector.

[0009] Furthermore, the desulfurized ammonia water tank is connected to the metering ammonia pump through a pipeline. In this preferred solution, the first acidity detector and the second acidity detector are used to sense the acidity of the liquid in the mixer, and the ammonia water is added to the mixer at an appropriate flow rate through the metering ammonia pump to reduce the acidity of the liquid.

[0010] Furthermore, the centrifuge is connected to a centrifuge metering feed pump via a pipeline. In this preferred embodiment, the centrifuge metering feed pump can add material according to the operation of the centrifuge to ensure that the feed liquid in the centrifuge does not exceed the upper limit of the centrifuge's working load.

[0011] Furthermore, an ammonia alarm device is provided in the centrifuge. In order to avoid excessive ammonia in the centrifuge, the preferred embodiment adds an ammonia alarm device. The acidity of the liquid entering the centrifuge from the mixer through the centrifuge metering feed pump can be further monitored to prevent the acidity monitoring of the liquid in the mixer from failing, and the centrifuge metering feed pump can be shut down in time to prevent the abnormal acidity liquid from being transmitted to the subsequent steps.

[0012] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0013] 1. In the production process, in order to adjust the acidity and control the product quality, it is necessary to detect the pH of the slurry in the desulfurization tower in real time. However, in the actual process, due to the continuous production method adopted in industry, slurry is continuously produced from the desulfurization tower, so there is a certain hysteresis in the adjustment of the pH of the slurry. Even if the acidity of the slurry in the desulfurization tower is found to be abnormal, the pH of the slurry in the desulfurization tower can only be adjusted. The pH of the output slurry still exceeds the standard, resulting in excessive free acid concentration. The utility model sets a mixer between the thickener and the centrifuge. The mixer has two functions. First, it serves as a buffer temporary storage container to receive the feed liquid from the thickener outlet, and secondly, it serves as a mixing reaction device to provide a reaction space for the combination of ammonia water and feed liquid. The mixer has two inlets, one of which is connected to the metering feed pump through a pipeline to receive the incoming feed liquid, and the other inlet is connected to the metering ammonia pump through a pipeline to receive the incoming ammonia water. After meeting the requirements, the feed liquid is output to the centrifuge metering feed pump through a pipeline for subsequent processes.

[0014] 2. The utility model controls the feeding speed through a metering feeding pump to prepare for the subsequent feed liquid to enter the mixer, control the flow rate not to exceed the maximum load of the mixer, and facilitate the subsequent detection and regulation of the acidity of the feed liquid. The utility model uses a first acidity detector to monitor the acidity of the feed liquid output from the thickener in real time, so as to cooperate with the subsequent second acidity detector and the metering ammonia pump to control the acidity of the feed liquid. The utility model uses a second acidity detector to monitor the acidity of the feed liquid in the mixer in real time. The utility model realizes the perception of the acidity of the feed liquid in the mixer through the cooperation of the first acidity detector and the second acidity detector, and adds ammonia water to the mixer at an appropriate flow rate through the metering ammonia pump, which plays a role in reducing the acidity of the feed liquid.

[0015] 3. The centrifuge of the utility model is connected to the centrifuge metering feed pump through a pipeline. The centrifuge metering feed pump of the utility model can add materials according to the operation of the centrifuge to ensure that the feed liquid in the centrifuge does not exceed the upper limit of the working load of the centrifuge. In order to avoid excessive ammonia in the centrifuge, the utility model adds an ammonia alarm device. The acidity of the feed liquid entering the centrifuge from the mixer through the centrifuge metering feed pump can be further monitored to prevent the acidity monitoring of the feed liquid in the mixer from failing, and the centrifuge metering feed pump can be shut down in time to prevent abnormal acidity of the feed liquid from being transmitted to subsequent steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the utility model system;

[0017] In the figure: 1. thickener; 2. metering discharge pump; 3. metering ammonia adding pump; 4. centrifuge metering feed pump; 5. centrifuge; 6. desulfurized ammonia water tank; 7. mixer; 8. ammonia alarm device; 9. first acidity detector; 10. second acidity detector. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments. It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which the present application belongs.

[0019] like Figure 1 As shown, an embodiment of the utility model provides an ammonia desulfurization system, including a mixer 7, wherein the mixer 7 is connected to a metering feed pump 2, a metering ammonia pump 3 and a centrifuge metering feed pump 4 through a pipeline. A thickener 1 is connected to the metering feed pump 2 through a pipeline. A first acidity detector 7 is arranged between the outlet of the thickener 1 and the metering feed pump 2. A second acidity detector 10 is arranged in the mixer 7. The desulfurization ammonia water tank is connected to the metering ammonia pump 3 through a pipeline. The centrifuge 5 is connected to the centrifuge metering feed pump 4 through a pipeline. An ammonia alarm device 8 is arranged in the centrifuge 5.

[0020] In the production process, in order to adjust the acidity and control the product quality, it is necessary to detect the pH of the slurry in the desulfurization tower in real time. However, in the actual process, due to the continuous production method adopted in industry, slurry is continuously produced from the desulfurization tower, so there is a certain hysteresis in the adjustment of the pH of the slurry. Even if the acidity of the slurry in the desulfurization tower is found to be abnormal, the pH of the slurry in the desulfurization tower can only be adjusted. The pH of the slurry that has been output still exceeds the standard, resulting in excessive free acid concentration. The utility model sets a mixer 7 between the thickener 1 and the centrifuge 5. The mixer 7 has two functions. First, it serves as a buffer temporary storage container to receive the feed liquid from the outlet of the thickener 1, and secondly, it serves as a mixing reaction device to provide a reaction space for the combination of ammonia water and feed liquid. The mixer 7 has two inlets, one of which is connected to the metering feed pump 2 through a pipeline to receive the incoming feed liquid, and the other inlet is connected to the metering ammonia pump 3 through a pipeline to receive the incoming ammonia water. After meeting the requirements, the feed liquid is output to the centrifuge metering feed pump 4 through a pipeline for subsequent processes.

[0021] The utility model controls the feeding speed through the metering feeding pump 2, prepares for the subsequent feed liquid to enter the mixer, controls the flow rate not to exceed the maximum load of the mixer, and facilitates the subsequent detection and regulation of the acidity of the feed liquid. The utility model uses the first acidity detector 9 to monitor the acidity of the feed liquid output from the thickener 1 in real time, so as to cooperate with the subsequent second acidity detector 10 and the metering ammonia pump 3 to regulate the acidity of the feed liquid. The utility model uses the second acidity detector 10 to monitor the acidity of the feed liquid in the mixer 7 in real time. The utility model realizes the perception of the acidity of the feed liquid in the mixer through the cooperation of the first acidity detector 9 and the second acidity detector 10, and adds ammonia water to the mixer 7 at an appropriate flow rate through the metering ammonia pump 3, which plays a role in reducing the acidity of the feed liquid.

[0022] The centrifuge 5 of the utility model is connected to the centrifuge metering feed pump 4 through a pipeline. The centrifuge metering feed pump 4 of the utility model can add materials according to the operation of the centrifuge 5 to ensure that the feed liquid in the centrifuge 5 does not exceed the upper limit of the working load of the centrifuge 5. In order to avoid excessive ammonia in the centrifuge 5, the utility model adds an ammonia alarm device 8 and a BAOSHIAN BH-60 industrial gas alarm gas detector, which can further monitor the acidity of the feed liquid entering the centrifuge 7 from the mixer 7 through the centrifuge metering feed pump 4, prevent the acidity monitoring of the feed liquid in the mixer 7 from failing, and timely shut down the pump through the centrifuge metering feed pump 4 to prevent the abnormal acidity of the feed liquid from being transmitted to the subsequent steps.

[0023] When in use, the feed liquid enters the mixer 7 from the thickener 1 through the first acidity detector 9 and the metering feed pump 2. The acidity of the feed liquid in the mixer 7 can be monitored in real time by the second acidity detector 10, and is mixed with the ammonia water entering through the metering ammonia pump 3. The feed liquid with adjusted acidity enters the centrifuge 5 through the centrifuge metering feed pump 4.

[0024] In actual production, due to the risk of excessive free acid in ammonium sulfate products, this system can be used to control the amount of ammonia added according to the detection index of free acid in the product to reduce the acidity of ammonium sulfate slurry and improve the product qualification rate to meet production needs. At the same time, this system takes into account the cost of production pipeline transformation, so the new system does not require a major transformation of the original production system. It only needs to add an ammonia pipeline to maximize the use of existing pipelines while meeting the acidity adjustment requirements and saving production costs.

[0025] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An ammonia desulfurization system, characterized in that: The invention comprises a mixer (7), wherein the mixer (7) is connected to a metering feed pump (2), a metering ammonia addition pump (3) and a centrifuge metering feed pump (4) through pipelines.

2. The ammonia desulfurization system according to claim 1, characterized in that: The thickener (1) is connected to the metering feed pump (2) through a pipeline.

3. The ammonia desulfurization system according to claim 2, characterized in that: A first acidity detector (9) is arranged between the thickener (1) outlet and the metering feed pump (2).

4. The ammonia desulfurization system according to claim 1, characterized in that: A second acidity detector (10) is arranged in the mixer (7).

5. The ammonia desulfurization system according to claim 1, characterized in that: The desulfurized ammonia water tank is connected to the metering ammonia pump (3) through a pipeline.

6. The ammonia desulfurization system according to claim 1, characterized in that: The centrifuge (5) is connected to the centrifuge metering feed pump (4) through a pipeline.

7. The ammonia desulfurization system according to claim 1, characterized in that: An ammonia alarm device (8) is arranged inside the centrifuge (5).

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