Device for treating impurities in unqualified ethylbenzene
The device, consisting of a centrifugal pump, regulating valve, and bleaching clay, solved the problem of alkaline nitrogen compounds affecting the catalyst during the re-distillation of ethylbenzene, achieving the effects of extending catalyst life and reducing costs.
Patent Information
- Application Number
- CN202422897572.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-11-27
AI Technical Summary
In the existing technology, the content of basic nitrogen compounds in the re-distilled ethylbenzene is relatively high, which affects the alkylation reaction catalyst, leading to catalyst deactivation. Furthermore, the content has not been effectively reduced to below the allowable level, affecting the catalyst life and usage cost.
The device, consisting of a centrifugal pump, regulating valve, processor, and bleaching clay connected by pipelines, neutralizes alkaline nitrogen compounds through contact between the bleaching clay and substandard ethylbenzene. Combined with the design of safety valves, check valves, and figure-eight blind flanges, it ensures forward flow and safe operation while reducing the content of alkaline nitrogen compounds.
It effectively reduces the content of basic nitrogen compounds in substandard ethylbenzene, extends catalyst life, reduces usage costs, and improves the quality of ethylbenzene products.
Smart Images
Figure CN223490441U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of chemical process technology, specifically relating to a device for treating impurities in substandard ethylbenzene. Background Technology
[0002] The ethylbenzene unit of a styrene plant uses benzene and ethylene as raw materials, reacting them in a reactor to produce ethylbenzene, with a small amount of polyethylbenzene as a byproduct. During the start-up and shutdown chemical treatment processes, substandard products from the ethylbenzene unit are discharged into a substandard ethylbenzene tank. To handle the material in the substandard ethylbenzene tank, ethylbenzene is recycled and re-distilled to produce qualified ethylbenzene. However, the recycled ethylbenzene has a high content of basic nitrogen compounds (4-5 mg / kg), which significantly affects the alkylation catalyst and easily causes catalyst deactivation. If the content of basic nitrogen compounds in the recycled ethylbenzene can be reduced to below the allowable level (1 mg / kg), the impact on the alkylation catalyst will be smaller, allowing for recycling and reuse, thus generating more revenue for the company. Utility Model Content
[0003] The purpose of this invention is to provide an apparatus for treating impurities in substandard ethylbenzene, which can effectively reduce the impact of basic nitrides in the material on the alkylation reaction catalyst, improve catalyst life, and reduce the cost of catalyst use.
[0004] The present invention discloses an apparatus for treating impurities in substandard ethylbenzene, comprising a centrifugal pump 1, a regulating valve 3, a treatment drain 4, an empty drain 5, and a processor 6 connected in sequence by pipelines. A substandard ethylbenzene discharge pipe is installed after the processor 6. The rear end of the substandard ethylbenzene discharge pipe is divided into a first branch and a second branch. The first branch connects to the reflux pipeline of the distillation tower in the styrene unit, and the second branch connects to the low-pressure flare pipe. A first figure-eight blind flange 81 and a first check valve 91 are sequentially installed on the first branch, and a second figure-eight blind flange 82 and a second check valve 92 are sequentially installed on the second branch. The processor 6 has a tank structure. The diameter of the regulating valve 3 is smaller than the diameter of the pipelines connected to its front and rear ends, and a reducer 2 is installed at both the front and rear ends of the regulating valve 3. A safety valve 7 is installed at the top of the processor 6, and the processor 6 is filled with bleaching clay. Attached Figure Description
[0005] Figure 1 This is a schematic diagram of a device for treating impurities in substandard ethylbenzene.
[0006] The names of the parts in the figure are: centrifugal pump 1, reducer 2, regulating valve 3, treatment drain 4, drain drain 5, processor 6, safety valve 7, first figure-eight blind plate 81, second figure-eight blind plate 82, first check valve 91 and second check valve 92; the specifications and models of the components suitable for this utility model are shown in Table 1.
[0007] Table 1: Specifications and Models of Each Component of This Utility Model
[0008]
[0009] Detailed Implementation
[0010] Example 1
[0011] The device described in this invention can effectively reduce the impurity content in substandard ethylbenzene. Specifically, the substandard ethylbenzene to be processed is transported to the regulating valve 3 via pipeline by the centrifugal pump 1, and the flow rate is adjusted by the regulating valve 3 (5-8 m³ / h). 3 After passing through the processor 6, the material enters and comes into full contact with the bleaching clay (meeting the YC series of granular bleaching clay Q / YSH 001-2023 standard). The acidic substances in the bleaching clay neutralize the alkaline nitrogen compounds in the unqualified ethylbenzene, thereby effectively reducing the content of alkaline nitrogen compounds in the unqualified ethylbenzene. After that, the qualified material is sent out of the device. A safety valve 7 is provided on the top of the processor 6 to prevent the processor 6 from exceeding the set pressure (0.25~0.3MPaG). A processing drain 4 and a drain 5 are provided on the pipeline between the regulating valve 3 and the processor 6. The processing drain 4 is opened during the maintenance of the processor 6 to discharge the unqualified ethylbenzene in the processor 6. The drain 5 is opened when the processor 6 is filled with unqualified ethylbenzene to vent and ensure that the processor 6 is full. When the bleaching clay in the processor 6 is replaced, the unqualified ethylbenzene can be released to the low-pressure flare for combustion. A check valve is provided at the rear end of the figure-eight blind plate to prevent the material from flowing back into the processor 6.
[0012] Centrifugal pump 1 uses centrifugal force to transport the unqualified ethylbenzene to be processed into regulating valve 3. By changing the opening of the valve core of regulating valve 3, the flow rate of unqualified ethylbenzene can be increased or decreased to control the flow rate of unqualified ethylbenzene into the system. The diameter of regulating valve 3 is one to two sizes smaller than the pipeline. The diameter of the pipeline at the front end of regulating valve 3 is reduced from 4 inches to 3 inches by reducing the diameter of the pipeline at the front end of regulating valve 3 to increase the pressure in front of regulating valve 3, making the regulation more sensitive and better realizing automatic regulation. The diameter of the pipeline at the rear end of regulating valve 3 is increased from 3 inches to 4 inches by reducing the diameter of the pipeline at the rear end of regulating valve 3 to restore the pipeline flow rate of the system.
[0013] The active ingredient, bleaching clay, loaded in processor 6 comes into contact with the substandard ethylbenzene transported by centrifugal pump 1 from top to bottom. This reduces the content of alkaline nitrogen compounds in the substandard ethylbenzene, resulting in qualified ethylbenzene and thus reducing the impact on the catalyst caused by the re-distillation of substandard ethylbenzene.
[0014] Safety valve 7 is positioned above processor 6 to ensure that processor 6 does not exceed its design pressure.
[0015] The first branch of the non-conforming ethylbenzene discharge pipe connects to the reflux pipeline of the styrene unit's distillation tower, sending the qualified ethylbenzene, whose alkaline nitrogen compounds have been reduced, to the styrene unit's distillation tower for reflux. The second branch of the non-conforming ethylbenzene discharge pipe connects to the low-pressure flare pipeline, burning the non-conforming ethylbenzene. Under normal operating conditions, the first figure-eight blind flange 81 to the styrene unit's distillation tower reflux pipeline is set to orifice plate mode, and the second figure-eight blind flange 82 to the low-pressure flare pipeline is set to blind plate mode. When the bleaching clay in the processor 6 reaches the end of its service life, it needs to be replaced or regenerated. In this case, the first figure-eight blind flange 81 to the styrene unit's distillation tower reflux pipeline is set to blind plate mode, and the second figure-eight blind flange 82 to the low-pressure flare pipeline is set to orifice plate mode, and the non-conforming ethylbenzene is burned through the low-pressure flare pipeline. The function of the first check valve 91 and the second check valve 92 is to prevent the non-conforming ethylbenzene from flowing backward during the entire system processing, ensuring that the entire processing process proceeds in the forward direction. During actual operation, the processor should be inspected more frequently to ensure that the clay processor is operated with full liquid to ensure the safety of the equipment.
Claims
1. An apparatus for treating impurities in substandard ethylbenzene, characterized in that: It consists of a centrifugal pump (1), a regulating valve (3) and a processor (6) connected in sequence by pipelines. A non-conforming ethylbenzene discharge pipe is set after the processor (6). The rear end of the non-conforming ethylbenzene discharge pipe is divided into a first branch and a second branch. The first branch is connected to the reflux pipeline of the distillation tower of the styrene unit, and the second branch is connected to the low-pressure flare pipe. A first figure-eight blind plate (81) is set on the first branch, and a second figure-eight blind plate (82) is set on the second branch. The processor (6) is filled with white clay. The non-conforming ethylbenzene to be processed is transported by the centrifugal pump (1) through the pipeline to the regulating valve (3) and then enters the processor (6).
2. The apparatus for treating impurities in substandard ethylbenzene as described in claim 1, characterized in that: A treatment drain (4) and a drain drain (5) are installed on the pipeline between the regulating valve (3) and the processor (6).
3. The apparatus for treating impurities in substandard ethylbenzene as described in claim 1, characterized in that: The processor (6) has a tank structure and a safety valve (7) is installed on the top of the processor (6).
4. The apparatus for treating impurities in substandard ethylbenzene as described in claim 1, characterized in that: The diameter of the regulating valve (3) is smaller than the diameter of the pipelines connected to its front and rear ends. A reducer (2) is provided at both the front and rear ends of the regulating valve (3).
5. The apparatus for treating impurities in substandard ethylbenzene as described in claim 1, characterized in that: A first check valve (91) is installed on the pipeline behind the first figure-eight blind flange (81), and a second check valve (92) is installed on the pipeline behind the second figure-eight blind flange (82).