Distillation system for removing low-boiling-point halogenated hydrocarbon in sulfuric acid

Abstract

The utility model discloses a distillation system for removing low-boiling-point halogenated hydrocarbon in sulfuric acid, which comprises a film evaporator, a material inlet pipe for inputting sulfuric acid is arranged at the top of one side of the film evaporator, and two graphite falling film condensers are connected in series with the top of the other side of the film evaporator through pipelines. A liquid phase output pipe is arranged at the bottom of the graphite falling film condenser, and a gas phase output pipe is arranged at the bottom of one side of the graphite falling film condenser; the bottom of the film evaporator is connected with an inlet of a sulfuric acid receiving tank through a pipeline, and the byproduct sulfuric acid is conveyed to a sulfuric acid tank area by the bottom of the sulfuric acid receiving tank through a sulfuric acid output pipe. After the byproduct sulfuric acid is desolventized by the film evaporator, the gas-phase dichloromethane is recovered through the multi-stage condenser and adsorption; liquid-phase sulfuric acid continuously enters the sulfuric acid receiving tank, then is conveyed to a sulfuric acid tank area through the sulfuric acid conveying pump, and then is conveyed to the sulfuric acid cracking device for treatment, so that the corrosion of pipeline equipment of the subsequent sulfuric acid cracking device is reduced to the minimum.

Description

Technical Field

[0001] The utility model relates to the technical field of evaporation systems, in particular to a distillation system for removing low-boiling-point halogenated hydrocarbons from sulfuric acid. Background Art

[0002] In the prior art, a certain amount of by-product sulfuric acid is generally produced in the organic matter sulfonation reaction process, and the by-product sulfuric acid contains a small amount of solvents or organic matter such as raw materials and products. The technical method for completely harmless by-product sulfuric acid generally adopts sulfuric acid cracking technology, which can completely decompose the organic matter in the by-product sulfuric acid at high temperature. However, if sulfuric acid contains a small amount of halogenated hydrocarbon solvents (such as dichloromethane), it will seriously corrode the pipeline equipment of the cracking device at high temperature; therefore, the harmful halogenated hydrocarbon impurities in the by-product sulfuric acid must be removed to protect the safe and stable operation of the cracking equipment.

[0003] Based on the above situation, the utility model proposes a distillation system for removing low-boiling-point halogenated hydrocarbons from sulfuric acid, which can effectively solve the above problems. Utility Model Content

[0004] The utility model aims to provide a distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid. A thin film evaporator is installed in a sulfonation process, by-product sulfuric acid after extraction is continuously pumped into the thin film evaporator, the temperature is increased for desolvation, and after the by-product sulfuric acid is desolvated by the thin film evaporator, the gas phase dichloromethane is recovered through a multi-stage condenser and adsorption; the liquid phase sulfuric acid continuously enters the sulfuric acid receiving tank, and then is transported to the sulfuric acid tank area through a sulfuric acid delivery pump, and then sent to a sulfuric acid cracking device for treatment, so that the corrosion of the subsequent sulfuric acid cracking device pipeline equipment is minimized, and part of the solvent dichloromethane is recovered, the neutralization treatment cost of waste acid water is reduced, and the waste water discharge amount is reduced.

[0005] The utility model is realized by the following technical solutions:

[0006] A distillation system for removing low-boiling-point halogenated hydrocarbons from sulfuric acid comprises a thin film evaporator, wherein a material inlet pipe for inputting sulfuric acid is arranged at the top of one side of the thin film evaporator, two graphite falling film condensers are connected in series via pipelines at the top of the other side of the thin film evaporator, a liquid phase output pipe is arranged at the bottom of the graphite falling film condenser, and a gas phase output pipe is arranged at the bottom of one side of the graphite falling film condenser; the bottom of the thin film evaporator is connected to the inlet of a sulfuric acid receiving tank via a pipeline, and the bottom of the sulfuric acid receiving tank transports byproduct sulfuric acid to a sulfuric acid tank area via the sulfuric acid output pipe.

[0007] According to the above technical solution, as a further preferred technical solution of the above technical solution, a condensate outlet pipe is provided at the bottom of one side of the thin film evaporator.

[0008] According to the above technical solution, as a further preferred technical solution of the above technical solution, a rotating shaft is arranged inside the thin film evaporator, a scraper is connected to the top of the rotating shaft, the top of the rotating shaft is fixedly connected to the output end of the driving motor, and the driving motor is fixedly connected to the top of the thin film evaporator.

[0009] According to the above technical solution, as a further preferred technical solution of the above technical solution, a sulfuric acid delivery pump is connected to the sulfuric acid output pipe.

[0010] According to the above technical solution, as a further preferred technical solution of the above technical solution, a cooling water supply pipe is provided on the bottom side of the graphite falling film condenser; and a cooling water return pipe is provided on the top side of the graphite falling film condenser.

[0011] According to the above technical solution, as a further preferred technical solution of the above technical solution, the top of the sulfuric acid receiving tank is connected with a tail gas exhaust pipe.

[0012] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0013] The utility model provides a distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid. A thin film evaporator is installed in a sulfonation process, by-product sulfuric acid after extraction is continuously pumped into the thin film evaporator, the temperature is increased for desolvation, and after the by-product sulfuric acid is desolvated by the thin film evaporator, gaseous dichloromethane is recovered through a multi-stage condenser and adsorption; liquid sulfuric acid continuously enters a sulfuric acid receiving tank, and is then transported to a sulfuric acid tank area through a sulfuric acid delivery pump, and then sent to a sulfuric acid cracking device for treatment, thereby minimizing the corrosion of subsequent pipeline equipment of the sulfuric acid cracking device, and recovering part of the solvent dichloromethane, reducing the neutralization treatment cost of waste acid water, and reducing the amount of waste water discharged. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a process flow chart of the utility model. DETAILED DESCRIPTION

[0015] In order to enable those skilled in the art to better understand the technical solution of the utility model, the preferred implementation scheme of the utility model is described below in conjunction with specific embodiments. However, it should be understood that the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The positional relationship described in the drawings is only used for illustrative purposes and cannot be understood as a limitation on this patent.

[0016] A distillation system for removing low-boiling-point halogenated hydrocarbons from sulfuric acid comprises a thin film evaporator 1, wherein a material inlet pipe 2 for inputting sulfuric acid is arranged at the top of one side of the thin film evaporator 1, and the top of the other side of the thin film evaporator 1 is connected to the air inlets of two graphite falling film condensers 3 connected in series through a pipeline, a liquid phase output pipe 4 is arranged at the bottom of the graphite falling film condenser 3, and a gas phase output pipe 5 is arranged at the bottom of one side of the graphite falling film condenser 3; the bottom of the thin film evaporator 1 is connected to the inlet of a sulfuric acid receiving tank 6 through a pipeline, and the bottom of the sulfuric acid receiving tank 6 transports byproduct sulfuric acid to a sulfuric acid tank area 8 through a sulfuric acid output pipe 7.

[0017] The utility model installs a thin film evaporator 1 in the sulfonation process, continuously injects the by-product sulfuric acid after extraction into the thin film evaporator 1, heats up and desolventizes, and after the by-product sulfuric acid is desolventized by the thin film evaporator 1, the gas phase dichloromethane is recovered through a multi-stage condenser (that is, two graphite falling film condensers 3 connected in series) and adsorption (solvent drying system (not shown in the figure)); the liquid phase sulfuric acid continuously enters the sulfuric acid receiving tank, and then is transported to the sulfuric acid tank area through a sulfuric acid delivery pump, and then sent to the sulfuric acid cracking device for treatment, so that the corrosion of the subsequent sulfuric acid cracking device pipeline equipment is minimized, and part of the solvent dichloromethane is recovered, the neutralization treatment cost of the waste acid water is reduced, and the waste water discharge amount is reduced.

[0018] Furthermore, in another embodiment, a condensate outlet pipe 9 is provided at the bottom of one side of the thin film evaporator 1 .

[0019] Further, in another embodiment, a rotating shaft 10 is provided inside the thin film evaporator 1, a scraper 11 is connected to the top of the rotating shaft 10, the top of the rotating shaft 10 is fixedly connected to the output end of the driving motor 12, and the driving motor 12 is fixedly connected to the top of the thin film evaporator 1. The utility model drives the rotating shaft 10 to rotate at a certain speed in the thin film evaporator 1 through the driving motor 12, and the scraper 11 on the rotating shaft 10 forms a uniform thin film on the inner wall of the thin film evaporator 1, so that falling film evaporation can be performed at a certain temperature.

[0020] Furthermore, in another embodiment, the sulfuric acid output pipe 7 is connected to a sulfuric acid delivery pump 13 .

[0021] Furthermore, in another embodiment, a cooling water supply pipe 14 is provided on one side of the bottom of the graphite falling film condenser 3 ; and a cooling water return pipe 15 is provided on one side of the top of the graphite falling film condenser 3 .

[0022] Furthermore, in another embodiment, a tail gas exhaust pipe 16 is connected to the top of the sulfuric acid receiving tank 6 .

[0023] According to the description and drawings of the utility model, those skilled in the art can easily manufacture or use the distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid of the utility model, and can produce the positive effects recorded in the utility model.

[0024] Unless otherwise specified, in the present invention, the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicating orientation or positional relationships are based on the orientation or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the orientation or positional relationship in the present invention are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood in conjunction with the drawings and according to specific circumstances.

[0025] Unless otherwise specified and limited, in the present invention, the terms "disposed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid, characterized in that: The invention comprises a thin film evaporator (1), wherein a material inlet pipe (2) for inputting sulfuric acid is arranged at the top of one side of the thin film evaporator (1), two graphite falling film condensers (3) are connected in series via a pipeline at the top of the other side of the thin film evaporator (1), a liquid phase output pipe (4) is arranged at the bottom of the graphite falling film condenser (3), and a gas phase output pipe (5) is arranged at the bottom of one side of the graphite falling film condenser (3); the bottom of the thin film evaporator (1) is connected to the inlet of a sulfuric acid receiving tank (6) via a pipeline, and the bottom of the sulfuric acid receiving tank (6) transports by-product sulfuric acid to a sulfuric acid tank area (8) via a sulfuric acid output pipe (7).

2. The distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid according to claim 1, characterized in that: A condensate outlet pipe (9) is provided at the bottom of one side of the thin film evaporator (1).

3. The distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid according to claim 1, characterized in that: A rotating shaft (10) is arranged inside the thin film evaporator (1), a scraper (11) is connected to the top of the rotating shaft (10), the top of the rotating shaft (10) is fixedly connected to the output end of a driving motor (12), and the driving motor (12) is fixedly connected to the top of the thin film evaporator (1).

4. The distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid according to claim 1, characterized in that: The sulfuric acid output pipe (7) is connected to a sulfuric acid delivery pump (13).

5. The distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid according to claim 1, characterized in that: A cooling water supply pipe (14) is provided on one side of the bottom of the graphite falling film condenser (3); and a cooling water return pipe (15) is provided on one side of the top of the graphite falling film condenser (3).

6. The distillation system for removing low-boiling halogenated hydrocarbons from sulfuric acid according to claim 1, characterized in that: The top of the sulfuric acid receiving tank (6) is connected to a tail gas exhaust pipe (16).

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