Hexanediamine plant catalyst automatic addition system and method
By designing an automatic catalyst addition system, the problems of safety hazards and low efficiency in catalyst addition were solved. The system enables continuous and quantitative addition of catalyst, which improves the safety and efficiency of hexamethylenediamine production, reduces catalyst consumption, and enhances reaction yield and product quality.
Patent Information
- Application Number
- CN202611147125.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-30
- Publication Date
- 2026-11-06
AI Technical Summary
The current method of catalyst addition in hexamethylenediamine production poses safety hazards, has low efficiency, causes fluctuations in catalyst activity and particle size, affects reaction yield and product quality stability, and has high catalyst consumption per unit.
Design an automatic catalyst addition system, including a catalyst stirring device, a transfer pump, an elevated tank, a time program controller, and a feed tank. The catalyst slurry is added in a timed and quantitative manner through the stirrer and the time program controller, avoiding the need for high-altitude hoisting and shutdown of the water washing and regeneration system.
This enables continuous and automated addition of catalysts, improving production safety and labor efficiency, reducing catalyst consumption per unit, maintaining catalyst activity and particle size stability within the reactor, and enhancing reaction yield and product quality stability.
Smart Images
Figure CN123038738A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of hexamethylenediamine production technology, specifically relating to an automatic catalyst addition system and method for hexamethylenediamine production. Background Technology
[0002] The hydrogenation of adiponitrile to produce hexamethylenediamine is the mainstream process for hexamethylenediamine production, and Raney nickel catalyst is the core catalyst for this reaction. In recent years, the catalyst form has been upgraded from traditional nickel-aluminum alloy powder to amorphous aluminum-nickel alloy catalyst, eliminating the need for on-site manual alloy powder collection and activation processes, thus simplifying the operation process. Existing processes typically involve hoisting the catalyst to a high position in the equipment and adding it through a feeding hopper, allowing it to enter the reactor and participate in the hydrogenation reaction.
[0003] However, the existing addition method poses significant safety hazards, is inefficient, and does not meet the requirements of safe production and enterprise development. Furthermore, adding fresh catalyst requires shutting down the catalyst washing and regeneration system and washing and purging the catalyst extraction system, resulting in some catalyst being lost with the overflow water, increasing catalyst consumption per unit. Centralized addition leads to significant fluctuations in catalyst activity and particle size within the reactor, disrupting the dynamic equilibrium of the catalyst system, hindering the complete hydrogenation of adiponitrile, and reducing reaction yield and product quality stability.
[0004] Therefore, there is an urgent need for an automatic catalyst addition system and method for hexamethylenediamine plants that is ingeniously designed, simple in structure, and capable of continuous and automatic catalyst addition, thereby improving reaction yield, ensuring production safety, reducing production costs, and increasing enterprise efficiency. This is a problem that needs to be solved. Summary of the Invention
[0005] To address the technical problems mentioned in the background section, this invention proposes an automatic catalyst addition system and method for a hexamethylenediamine unit. The system is ingeniously designed and has a simple structure, enabling continuous automatic catalyst addition, improving reaction yield, ensuring production safety, reducing production costs, and increasing enterprise efficiency.
[0006] The technical solution of this invention is: an automatic catalyst addition system for a hexamethylenediamine unit, comprising a catalyst stirring device, a catalyst transfer pump, a catalyst high-level tank, a time program controller, and a catalyst feed tank; the outlet end of the catalyst stirring device is connected to the inlet end of the catalyst transfer pump, and the outlet end of the catalyst transfer pump is connected to the catalyst high-level tank via a pipeline; a stirrer is installed inside the catalyst high-level tank, and the stirrer operates continuously during catalyst conveying and discharge; the outlet of the catalyst high-level tank is connected to the catalyst feed tank via a pipeline, and a time program controller is installed on the outlet pipeline to control the opening and closing time of the catalyst high-level tank outlet valve, so as to achieve timed and quantitative discharge of catalyst.
[0007] As a further optimization of the above-mentioned automatic catalyst addition system for a hexamethylenediamine unit, the catalyst transfer pump is any one of a screw pump, a peristaltic pump, a centrifugal pump, a pneumatic diaphragm pump, and an electric diaphragm pump.
[0008] As a further optimization of the above-mentioned automatic catalyst addition system for a hexamethylenediamine unit, the outlet of the catalyst feed tank is connected to the reactor feed tank of the hexamethylenediamine unit.
[0009] An automated catalyst addition method for a hexamethylenediamine unit includes the following steps: Step 1: First, mix the amorphous aluminum-nickel alloy catalyst with demineralized water and stir evenly in a catalyst stirring device to prepare a catalyst slurry; Step two: Then start the catalyst transfer pump to transport the well-stirred catalyst slurry to the catalyst high-level tank through the pipeline; Step 3: Before receiving the catalyst slurry, the catalyst high-level tank is pre-filled with demineralized water at a level of 20%, and the agitator is running continuously throughout the process to prevent catalyst sedimentation. Step 4: Set the discharge time and discharge interval through the time program controller, and automatically control the opening and closing of the catalyst high-level tank discharge valve to discharge the catalyst slurry into the catalyst feed tank in a quantitative and timed manner through the pipeline. Step 5: The catalyst feed tank continuously discharges the catalyst slurry into the reactor feed tank, and then supplies it to the hydrogenation reactor through the reactor feed pump to participate in the hydrogenation reaction.
[0010] As a further optimization of the above-mentioned automatic catalyst addition method for a hexamethylenediamine unit, the catalyst delivery and addition process in steps two to four does not require the shutdown of the catalyst washing and regeneration system.
[0011] Compared with the prior art, the beneficial effects of the present invention are: First, it eliminates safety hazards: the catalyst addition operation eliminates the high-altitude hoisting process, avoiding the safety risks of catalyst tanks falling and spilling, while also reducing the number of workers and significantly improving production safety and labor efficiency.
[0012] Second, it reduces catalyst consumption per unit: it enables continuous addition of catalyst without shutting down the catalyst washing and regeneration system, thus avoiding catalyst loss caused by system purging.
[0013] Third, improve reaction yield: By automatically adding catalyst in a timed and quantitative manner, the dynamic balance of the catalyst system in the reactor is ensured, the catalyst activity and particle size remain stable, and the hydrogenation reaction of adiponitrile is fully carried out, which effectively improves the reaction yield and product quality stability. Attached Figure Description
[0014] Figure 1This is a schematic diagram of the overall structure and flow of the present invention; The diagram shows: 1. Catalyst stirring device, 2. Catalyst transfer pump, 3. Catalyst high-level tank, 4. Time program controller, 5. Catalyst feed tank, and 6. Reactor feed tank. Detailed Implementation
[0015] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.
[0016] like Figure 1 As shown, an automatic catalyst addition system for a hexamethylenediamine unit includes a catalyst stirring device 1, a catalyst transfer pump 2, a catalyst high-level tank 3, a time program controller 4, and a catalyst feed tank 5. The outlet end of the catalyst stirring device 1 is connected to the inlet end of the catalyst transfer pump 2, and the outlet end of the catalyst transfer pump 2 is connected to the catalyst high-level tank 3 via a pipeline. A stirrer is installed inside the catalyst high-level tank 3, and the stirrer operates continuously during catalyst conveying and discharge. The outlet of the catalyst high-level tank 3 is connected to the catalyst feed tank 5 via a pipeline, and a time program controller 4 is installed on the outlet pipeline. The time program controller 4 controls the opening and closing time of the outlet valve of the catalyst high-level tank 3 to achieve timed and quantitative discharge of the catalyst.
[0017] The catalyst transfer pump 2 is any one of a screw pump, peristaltic pump, centrifugal pump, pneumatic diaphragm pump, and electric diaphragm pump.
[0018] The outlet of the catalyst feed tank 5 is connected to the reactor feed tank 6 of the hexamethylenediamine unit.
[0019] An automated catalyst addition method for a hexamethylenediamine unit includes the following steps: Step 1: First, mix the amorphous aluminum-nickel alloy catalyst with demineralized water and stir evenly in catalyst stirring device 1 to prepare catalyst slurry; Step 2: Then start the catalyst transfer pump 2 to transport the well-stirred catalyst slurry to the catalyst high-level tank 3 through the pipeline; Step 3: Before receiving the catalyst slurry, the catalyst high-level tank 3 is pre-filled with demineralized water at a level of 20%, and the agitator runs continuously throughout the process to prevent catalyst sedimentation. Step 4: Set the discharge time and discharge interval through the time program controller 4, and automatically control the opening and closing of the discharge valve of the catalyst high-level tank 3 so that the catalyst slurry is discharged quantitatively and at regular intervals through the pipeline to the catalyst feed tank 5. Step 5: Catalyst feed tank 5 continuously discharges catalyst slurry into reactor feed tank 6, and then supplies it to hydrogenation reactor through reactor feed pump to participate in hydrogenation reaction.
[0020] The catalyst delivery and addition process in steps two through four does not require the catalyst washing and regeneration system to be shut down.
[0021] In practice, the specific steps are as follows: 1. Catalyst slurry preparation: Add 200L of demineralized water to the catalyst stirring device, slowly pour in 50 kg of amorphous aluminum-nickel alloy catalyst, start the stirrer and stir for 30 minutes until the catalyst is completely dispersed and a uniform catalyst slurry is formed.
[0022] 2. Slurry delivery: Start the pneumatic diaphragm pump to deliver the catalyst slurry in the mixing tank to the catalyst high-level tank through the pipeline. The delivery time is approximately 15 minutes. During the delivery process, the catalyst high-level tank is pre-maintained with demineralized water at a level of 20%, and the agitator runs at a speed of 60 r / min throughout the process.
[0023] 3. Automatic quantitative addition: The time program controller sets each discharge time to 30 seconds and the discharge interval to 30 minutes. The controller automatically controls the opening and closing of the pneumatic discharge valve at the bottom of the catalyst high-level tank according to the set program, and the catalyst flows into the catalyst feed tank through the pipeline.
[0024] 4. Reactor supply: The catalyst slurry in the catalyst feed tank is continuously transported to the reactor through pipeline to participate in the hydrogenation reaction.
[0025] This invention is ingeniously designed and has a simple structure, enabling continuous and automatic addition of catalysts, improving reaction yield, ensuring production safety, reducing production costs, and increasing enterprise efficiency.
[0026] The preferred embodiments and examples of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments and examples. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the concept of the present invention.
Claims
1. An automatic catalyst addition system for a hexamethylenediamine unit, characterized in that: The system includes a catalyst stirring device (1), a catalyst transfer pump (2), a catalyst high-level tank (3), a time program controller (4), and a catalyst feed tank (5). The outlet end of the catalyst stirring device (1) is connected to the inlet end of the catalyst transfer pump (2), and the outlet end of the catalyst transfer pump (2) is connected to the catalyst high-level tank (3) through a pipeline. A stirrer is installed in the catalyst high-level tank (3), and the stirrer runs continuously during the catalyst conveying and discharge process. The outlet of the catalyst high-level tank (3) is connected to the catalyst feed tank (5) through a pipeline. A time program controller (4) is installed on the outlet pipeline. The opening and closing time of the outlet valve of the catalyst high-level tank (3) is controlled by the time program controller (4) to achieve timed and quantitative discharge of the catalyst.
2. The automatic catalyst addition system for a hexamethylenediamine unit as described in claim 1, characterized in that: The catalyst transfer pump (2) is any one of a screw pump, peristaltic pump, centrifugal pump, pneumatic diaphragm pump and electric diaphragm pump.
3. The automatic catalyst addition system for a hexamethylenediamine unit as described in claim 1, characterized in that: The outlet of the catalyst feed tank (5) is connected to the reactor feed tank (6) of the hexamethylenediamine unit.
4. A method for automatically adding catalyst to a hexamethylenediamine unit based on any one of claims 1 to 3, characterized in that: Includes the following steps, Step 1: First, mix the amorphous aluminum-nickel alloy catalyst with demineralized water and stir evenly in the catalyst stirring device (1) to prepare the catalyst slurry. Step 2: Then start the catalyst transfer pump (2) to transport the well-stirred catalyst slurry to the catalyst high-level tank (3) through the pipeline. Step 3: Before receiving the catalyst slurry, the catalyst high-level tank (3) is pre-filled with demineralized water at a level of 20%, and the agitator is continuously running throughout the process to prevent the catalyst from settling. Step 4: Set the discharge time and discharge interval through the time program controller (4), and automatically control the opening and closing of the discharge valve of the catalyst high-level tank (3) so that the catalyst slurry is discharged quantitatively and at regular intervals through the pipeline to the catalyst feed tank (5). Step 5: The catalyst feed tank (5) continuously discharges the catalyst slurry into the reactor feed tank (6), and then supplies it to the hydrogenation reactor through the reactor feed pump to participate in the hydrogenation reaction.
5. The method for automatic catalyst addition in a hexamethylenediamine unit as described in claim 4, characterized in that: The catalyst delivery and addition process in steps two through four does not require the catalyst washing and regeneration system to be shut down.