A crude toluene waste oil recycling system

Abstract

The application provides a crude toluene waste oil recycling system, which comprises a crude toluene waste oil buffer tank, a flocculation tank, a toluene extraction tower, a toluene evaporation tower, a dichloromethane condenser and a dichloromethane buffer tank connected in sequence, wherein the toluene extraction tower is further connected with the dichloromethane buffer tank and a dichloromethane storage tank respectively, and the flocculation tank is further connected with a flocculant storage tank. The flocculant in the flocculant storage tank is added into the crude toluene waste oil, so that the polyol ketone and solid catalyst particles in the crude toluene waste oil are subjected to flocculation reaction to form an upper clear liquid rich in toluene and a solid fuel. The upper clear liquid is extracted by the toluene extraction tower and evaporated by the toluene evaporation tower to obtain toluene, so that toluene is recycled and the production cost is reduced. The solid fuel is sent to a coal yard, fully mixed with coal powder and combusted, so that the combustion performance of the coal powder is improved and profits are brought to the enterprise.

Description

Technical Field

[0001] This utility model belongs to the field of toluene refining technology and relates to a crude toluene waste oil recycling system. Background Technology

[0002] In the toluene refining process, toluene is typically used as the extractant, which results in the generation of a certain amount of crude toluene waste oil containing toluene, polyol ketones, and solid catalysts. This crude toluene waste oil is usually sent to zero-discharge wastewater treatment facilities for disposal, which not only burdens the company but also leads to the waste of the extractant toluene, resulting in cost losses. Utility Model Content

[0003] The purpose of this invention is to provide a crude toluene waste oil recycling system to solve the problem of toluene loss and waste in crude toluene waste oil.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] This application provides a crude toluene waste oil recycling system, which includes a crude toluene waste oil buffer tank, a flocculation tank, a toluene extraction tower, a toluene evaporation tower, a dichloromethane condenser, and a dichloromethane buffer tank connected in sequence. The toluene extraction tower is also connected to the dichloromethane buffer tank and a dichloromethane storage tank, and the flocculation tank is also connected to a flocculant storage tank.

[0006] Preferably, a pelletizer and a bagging machine are connected in sequence to the bottom of the flocculation tank.

[0007] Preferably, the toluene extraction tower is an extraction tower at ambient temperature and pressure.

[0008] Preferably, the toluene evaporator is an evaporator with a bottom temperature of 76-80°C.

[0009] Preferably, the height of the toluene extraction tower is 35m.

[0010] Preferably, the bottom of the flocculation tank is provided with two parallel pelletizers.

[0011] This utility model has the following beneficial effects:

[0012] In this application, flocculant from a flocculant storage tank is added to crude toluene waste oil, causing the polyol ketones and solid catalyst particles in the crude toluene waste oil to undergo a flocculation reaction, forming a toluene-rich supernatant and solid fuel. This supernatant is then extracted in a toluene extraction tower and evaporated in a toluene evaporation tower to obtain toluene, achieving toluene recovery and reducing production costs. The solid fuel is sent to the coal yard and thoroughly mixed with pulverized coal before combustion, improving the combustion performance of the pulverized coal and bringing profits to the enterprise. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the crude toluene waste oil recycling system provided in the embodiments of this application;

[0014] Symbolic representation:

[0015] 1-Crude toluene waste oil buffer tank, 2-Flocculation tank, 3-Toluene extraction tower, 4-Toluene evaporation tower, 5-Dichloromethane condenser, 6-Dichloromethane buffer tank, 7-Dichloromethane storage tank, 8-Flocculant storage tank, 9-Pelletizer, 10-Bagging machine. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] This application provides a crude toluene waste oil recycling system, which includes a crude toluene waste oil buffer tank 1, a flocculation tank 2, a toluene extraction tower 3, a toluene evaporation tower 4, a dichloromethane condenser 5, a dichloromethane buffer tank 6, and a dichloromethane storage tank 7 connected in sequence, as shown in the attached figure. Figure 1 As shown.

[0018] The crude toluene waste oil buffer tank 1 is a component for buffering and storing crude toluene waste oil, with a residence time of 70 minutes. After buffering, the crude toluene waste oil is introduced into the flocculation tank 2. Flocculant is added through the flocculant storage tank 8 and stirred to ensure flocculation of the polyol ketones and solid catalyst particles in the crude toluene waste oil, resulting in a supernatant and coagulated material. A stirrer is installed in the flocculation tank 2 to ensure thorough mixing of the crude toluene waste oil and flocculant. The flocculant used in this application is polyacrylamide, with a volume ratio of crude toluene waste oil to polyacrylamide of 1:1-1.2.

[0019] The toluene extraction tower 3 is the component for extracting toluene. The supernatant obtained from the flocculation tank 2 enters from the top of the toluene extraction tower 3, while dichloromethane stored in the dichloromethane storage tank 7 enters from the bottom of the toluene extraction tower 3 as the extractant. The two react countercurrently at room temperature and pressure within the toluene extraction tower 3, resulting in an extraction reaction that yields a toluene / dichloromethane mixture and waste liquid. This waste liquid is then fed into the crude toluene waste oil buffer tank 1 for further treatment. In this application, the volume ratio of the supernatant to dichloromethane is 1:1-1.12, and the height of the toluene extraction tower is 35m.

[0020] Furthermore, the bottom of the flocculation tank 2 is connected in sequence to a pelletizer 9 and a bagging machine 10. Thus, the condensed material and nitrogen obtained in the flocculation tank 2 are introduced into the pelletizer 9. With the assistance of nitrogen, the condensed material is pelletized and then packaged by the bagging machine 10 and transported to the coal yard for combustion.

[0021] Toluene evaporator 4 is a component for evaporating and processing a toluene / dichloromethane mixture. Specifically, in toluene evaporator 4, where the bottom temperature is 76-80℃, dichloromethane is easily evaporated within the toluene evaporator 4 due to its volatility and relatively small usage. Dichloromethane gas is formed at the top of the tower, while toluene is obtained at the bottom. In this application, to save energy, recycled hot water is used as a heat source to heat toluene evaporator 4.

[0022] In addition, the dichloromethane buffer tank 6 is also connected to the toluene extraction tower 3. Thus, the dichloromethane gas obtained from the top of the toluene evaporator 4 is condensed by the dichloromethane condenser 5 and buffered by the dichloromethane buffer tank 6, and then pumped back to the toluene extraction tower 3 to achieve recycling.

[0023] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A crude toluene waste oil recycling system, characterized in that, The system includes a crude toluene waste oil buffer tank (1), a flocculation tank (2), a toluene extraction tower (3), a toluene evaporation tower (4), a dichloromethane condenser (5), and a dichloromethane buffer tank (6) connected in sequence. The toluene extraction tower (3) is also connected to the dichloromethane buffer tank (6) and a dichloromethane storage tank (7). The flocculation tank (2) is also connected to a flocculant storage tank (8).

2. The crude toluene waste oil recycling system according to claim 1, characterized in that, The bottom of the flocculation tank (2) is also connected in sequence to a pelletizer (9) and a bagging machine (10).

3. The crude toluene waste oil recycling system according to claim 1, characterized in that, The toluene extraction tower (3) is an extraction tower at normal temperature and pressure.

4. The crude toluene waste oil recycling system according to claim 1, characterized in that, The toluene evaporator (4) is an evaporator with a bottom temperature of 76-80℃.

5. The crude toluene waste oil recycling system according to claim 1, characterized in that, The height of the toluene extraction tower (3) is 35m.

6. The crude toluene waste oil recycling system according to claim 2, characterized in that, The bottom of the flocculation tank (2) is provided with two parallel pelletizers (9).

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