A tetrabromoethane production device

Abstract

The utility model discloses a tetrabromoethane production device, and relates to the technical field of tetrabromoethane production. A packing layer is arranged in an absorption tower, an acetylene gas inlet is arranged at the lower part of the absorption tower, and a bromine inlet is arranged at the upper part of the absorption tower; the absorption tower is provided with a tetrabromoethane crude product outlet at the upper part of the acetylene gas inlet, and the gas phase outlet at the top of the absorption tower is connected with a first condenser through a pipeline. Acetylene gas will be broken into tiny bubbles when passing through the packing layer, which increases the gas-liquid contact area, enhances the absorption effect, and improves the yield of the product. At the same time, the bottom air intake increases the synthesis pressure of the absorption tower, which is conducive to accelerating the reaction and improving the reaction efficiency. At the same time, the raw materials react thoroughly, and it is not easy to form explosive gas at the top of the absorption tower, and the safety factor is higher. At the same time, the first condenser can greatly reduce the possibility of bromine overflowing into the air, avoid damage to the environment, and also reduce the waste of raw materials.

Description

Technical Field

[0001] The utility model relates to the technical field of tetrabromoethane production, in particular to a tetrabromoethane production device. Background Art

[0002] 1,1,2,2-Tetrabromoethane is a colorless or light yellow, highly refractive liquid with an iodoform odor. It is miscible with ethanol, ether, chloroform, aniline, and glacial acetic acid, but insoluble in water. Boiling point 243.5℃ (7.2kPa), 114℃ (0.267kPa). Relative density 2.9656 (20 / 4℃), refractive index 1.638. It can decompose when exposed to light and heat, and the color turns yellow. When the temperature is higher than 190℃, the decomposition product is highly toxic carbonyl bromide vapor. Tetrabromoethane is an important chemical additive. In the production process of polyester, the raw material for polyester, it is used as a catalyst for the oxidation of xylene to terephthalic acid; it is used as a flame retardant in artificial fibers, plastic products and expandable polystyrene foam; it is used as a catalyst in the production of trimellitic acid; it is also used as a flotation liquid for separating gravel, a dye intermediate, and a solvent for oils and waxes; it is used for the determination of the specific gravity and refractive index of ores; it is used in the synthesis of pesticides, microscope instrument cleaning agents, etc.

[0003] At present, tetrabromoethane is generally obtained by bromination with acetylene as raw material. The production process is as follows: raw material → synthesis → neutralization → distillation → product. Acetylene gas is generated by calcium carbide in an acetylene generator. After purification and drying, it enters the reactor to react with bromine to obtain crude tetrabromoethane; the crude tetrabromoethane is washed with alkali and water to remove acidic substances and water-soluble substances, and then refined by distillation to obtain tetrabromoethane products. At present, the reaction of acetylene and bromine is mostly carried out intermittently in a reactor. The heat generated by the reaction is controlled by cooling through a jacket using circulating water at normal temperature, but this process has the following problems:

[0004] 1. When acetylene is introduced into the reactor, the reaction between acetylene and bromine generates a large amount of heat, causing the temperature in the reactor to rise. The excessively high temperature causes part of the bromine in the reactor to volatilize and turn into bromine vapor, resulting in a waste of bromine in the synthesis process. The bromine vapor needs to be condensed and refluxed for reuse, resulting in a waste of energy.

[0005] 2. The volatile bromine vapor can easily form explosive gas with the acetylene gas that has not been completely absorbed. There is a large gas phase space in the reactor, which can easily cause safety accidents.

[0006] 3. After acetylene is introduced into the reactor, the large amount of heat generated by the reaction cannot be removed in time, so the acetylene gas flow rate introduced into the reactor can only be reduced to extend the reaction time. Therefore, this process has problems such as long reaction time, low production efficiency, many safety hazards, and unsatisfactory results. Summary of the invention

[0007] The technical problem to be solved by the utility model is: in view of the deficiencies in the prior art, a tetrabromoethane production device is provided, which has a high safety factor, can realize continuous production and has high production efficiency.

[0008] In order to solve the above technical problems, the technical solution of the utility model is:

[0009] A tetrabromoethane production device comprises an absorption tower, wherein a packing layer is arranged in the absorption tower, an acetylene gas inlet is arranged at the lower part of the absorption tower, and a bromine inlet is arranged at the upper part of the absorption tower;

[0010] The absorption tower is provided with a tetrabromoethane crude product outlet above the acetylene gas inlet, and the gas phase outlet at the top of the absorption tower is connected to the first condenser through a pipeline.

[0011] As an improved technical solution, a circulation pump is provided at the bottom of the absorption tower, the outlet of the circulation pump is connected to a second condenser through a pipeline, and the outlet of the second condenser is connected to an upper liquid return port of the absorption tower through a pipeline.

[0012] As an improved technical solution, the absorption tower is a multi-stage absorption tower, which includes a primary absorption tower, a secondary absorption tower and a tertiary absorption tower connected in sequence.

[0013] As an improved technical solution, the top gas phase outlets of the primary absorption tower and the secondary absorption tower are respectively connected to the lower gas phase inlets of the secondary absorption tower and the tertiary absorption tower through pipelines, and the bottom liquid phase outlets of the tertiary absorption tower and the secondary absorption tower are respectively connected to the upper liquid phase inlets of the secondary absorption tower and the primary absorption tower through pipelines;

[0014] The acetylene gas inlet and the tetrabromoethane crude product outlet are both arranged at the lower part of the primary absorption tower, the bromine inlet is arranged at the upper part of the tertiary absorption tower, the inlet of the first condenser is connected to the gas phase outlet of the tertiary absorption tower, and the outlet of the second condenser is connected to the upper liquid return port of the tertiary absorption tower through a pipeline.

[0015] As an improved technical solution, the packing layer is a packing layer composed of a plurality of glass balls.

[0016] As an improved technical solution, the diameter of the glass balls in the packing layer is 8-12 mm.

[0017] As a preferred technical solution, the ratio of the height of the packing layer to the inner diameter of the absorption tower is 30-50:7.

[0018] Due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0019] The utility model discloses a tetrabromoethane production device, comprising an absorption tower, wherein a packing layer is provided in the absorption tower, an acetylene gas inlet is provided at the lower part of the absorption tower, and a bromine inlet is provided at the upper part of the absorption tower; the absorption tower is provided with a tetrabromoethane crude product outlet at the upper part of the acetylene gas inlet, and the gas phase outlet at the top of the absorption tower is connected to a first condenser through a pipeline. After the acetylene gas enters the absorption tower, it contacts the bromine from top to bottom after entering the absorption tower. When the acetylene gas passes through the packing layer, it will be broken into tiny bubbles, thus increasing the gas-liquid contact area, enhancing the absorption effect, making the reaction of the raw materials more thorough, and improving the yield of the product. At the same time, the bottom air intake increases the synthesis pressure of the absorption tower, and the chemical reaction with the participation of gas increases the reaction pressure, which is conducive to accelerating the reaction and improving the reaction efficiency. At the same time, the raw materials react thoroughly, and it is not easy to form explosive gas at the top of the absorption tower, and the safety factor is higher. At the same time, the first condenser can greatly reduce the possibility of bromine overflowing into the air, avoid damage to the environment, and also reduce the waste of raw materials.

[0020] A circulating pump is provided at the bottom of the absorption tower, and the outlet of the circulating pump is connected to the second condenser through a pipeline, and the outlet of the second condenser is connected to the upper liquid return port of the absorption tower through a pipeline. The materials in the absorption tower are transferred to the second condenser for cooling by the circulating pump, and then sent to the absorption tower for circulation reaction. The mixing and cooling effects of the materials in the absorption tower are good, the reaction is more thorough, and the possibility of bromine evaporation waste due to excessively high material temperature is reduced.

[0021] The absorption tower is a multi-stage absorption tower, which includes a primary absorption tower, a secondary absorption tower and a tertiary absorption tower connected in sequence. Through multi-stage absorption, bromine and acetylene have a long contact time, a large release area, a more thorough reaction, and an improved reaction yield.

[0022] The top gas phase outlets of the primary absorption tower and the secondary absorption tower are respectively connected to the lower gas phase inlets of the secondary absorption tower and the tertiary absorption tower through pipelines, and the bottom liquid phase outlets of the tertiary absorption tower and the secondary absorption tower are respectively connected to the upper liquid phase inlets of the secondary absorption tower and the primary absorption tower through pipelines; the acetylene gas inlet and the tetrabromoethane crude product outlet are both arranged at the lower part of the primary absorption tower, the bromine inlet is arranged at the upper part of the tertiary absorption tower, the inlet of the first condenser is connected to the gas phase outlet of the tertiary absorption tower, and the outlet of the second condenser is connected to the upper liquid return port of the tertiary absorption tower through a pipeline. Acetylene gas gradually moves from the primary absorption tower to the tertiary absorption tower, while bromine moves from the tertiary absorption tower to the primary absorption tower. The two come into contact and react in multiple absorption towers, and the reaction volume is larger. The material in the primary absorption tower can be continuously transported to the second condenser through a circulation pump for cooling, and then enter the tertiary absorption tower again and move to the primary absorption tower with the newly added bromine. Finally, the product is collected from the crude tetrabromoethane outlet of the primary absorption tower. The small amount of bromine vapor generated in the reaction can be cooled and recovered through the first condenser and fall into the tertiary absorption tower to continue the reaction, avoiding the waste of raw materials. Through continuous circulation and feeding, continuous production is achieved.

[0023] The packing layer is composed of a plurality of glass balls. When acetylene gas passes through the packing layer, it will be broken into tiny bubbles by the glass balls, thus increasing the gas-liquid contact area, enhancing the absorption effect, and increasing the reaction yield.

[0024] The diameter of the glass balls in the packing layer is 8-12 mm, and the ratio of the height of the packing layer to the inner diameter of the absorption tower is 30-50:7. The large height-to-diameter ratio design increases the contact time of gas and liquid materials, makes the reaction more thorough, and improves the yield of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0026] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model;

[0027] Among them: 1. Absorption tower; 2. Packing layer; 3. Acetylene gas inlet; 4. Bromine inlet; 5. Tetrabromoethane crude product outlet; 6. First condenser; 7. Circulation pump; 8. Second condenser; 9. Primary absorption tower; 10. Secondary absorption tower; 11. Tertiary absorption tower. DETAILED DESCRIPTION

[0028] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0029] like Figure 1As shown, a tetrabromoethane production device comprises an absorption tower 1, wherein a packing layer 2 is provided in the absorption tower 1, an acetylene gas inlet 3 is provided at the lower part of the absorption tower 1, and a bromine inlet 4 is provided at the upper part of the absorption tower 1; the absorption tower 1 is provided with a tetrabromoethane crude product outlet 5 at the upper part of the acetylene gas inlet 3, and the gas phase outlet at the top of the absorption tower 1 is connected to a first condenser 6 through a pipeline. After the acetylene gas enters the absorption tower 1 from bottom to top, it contacts with the bromine from top to bottom after entering the absorption tower 1. When the acetylene gas passes through the packing layer 2, it will be broken into tiny bubbles, thereby increasing the gas-liquid contact area, enhancing the absorption effect, making the reaction of the raw materials more thorough, and improving the yield of the product. At the same time, the bottom air intake increases the synthesis pressure of the absorption tower 1, and the chemical reaction with the participation of gas increases the reaction pressure, which is conducive to accelerating the reaction and improving the reaction efficiency. At the same time, the raw materials react thoroughly, and it is not easy to form explosive gas at the top of the absorption tower 1, and the safety factor is higher. At the same time, the first condenser 6 can greatly reduce the possibility of bromine overflowing into the air, avoid damage to the environment, and also reduce the waste of raw materials.

[0030] A circulating pump 7 is provided at the bottom of the absorption tower 1, and the outlet of the circulating pump 7 is connected to the second condenser 8 through a pipeline, and the outlet of the second condenser 8 is connected to the upper liquid return port of the absorption tower 1 through a pipeline. The material in the absorption tower 1 is transferred to the second condenser 8 through the circulating pump 7 for cooling, and then sent to the absorption tower 1 for circulation reaction, the mixing and cooling effect of the material in the absorption tower 1 is good, the reaction is more thorough, and the possibility of bromine evaporation waste due to excessively high material temperature is reduced.

[0031] The absorption tower 1 is a multi-stage absorption tower, which includes a primary absorption tower 9, a secondary absorption tower 10 and a tertiary absorption tower 11 connected in sequence. Through multi-stage absorption, bromine and acetylene have a long contact time, a large release area, a more thorough reaction, and an improved reaction yield.

[0032] The top gas phase outlets of the primary absorption tower 9 and the secondary absorption tower 10 are respectively connected to the lower gas phase inlets of the secondary absorption tower 10 and the tertiary absorption tower 11 through pipelines, and the bottom liquid phase outlets of the tertiary absorption tower 11 and the secondary absorption tower 10 are respectively connected to the upper liquid phase inlets of the secondary absorption tower 10 and the primary absorption tower 9 through pipelines; the acetylene gas inlet 3 and the tetrabromoethane crude product outlet 5 are both arranged at the lower part of the primary absorption tower 9, the bromine inlet 4 is arranged at the upper part of the tertiary absorption tower 11, the inlet of the first condenser 6 is connected to the gas phase outlet of the tertiary absorption tower 11, and the outlet of the second condenser 8 is connected to the upper liquid return port of the tertiary absorption tower 11 through a pipeline. Acetylene gas gradually moves from the primary absorption tower 9 to the tertiary absorption tower 11, while bromine moves from the tertiary absorption tower 11 to the primary absorption tower 9. The two come into contact and react in multiple absorption towers 1, and the reaction volume is larger. The material in the primary absorption tower 9 can be continuously transported to the second condenser 8 through the circulation pump 7 for cooling, and then enter the tertiary absorption tower 11 again and then move to the primary absorption tower 9 together with the newly added bromine, and finally collect the product from the tetrabromoethane crude product outlet 5 of the primary absorption tower 9. The small amount of bromine vapor generated in the reaction can be cooled and recovered by the first condenser 6 and fall into the tertiary absorption tower 11 to continue the reaction, avoiding the waste of raw materials. Through continuous circulation and feeding, continuous production is achieved.

[0033] The packing layer 2 is composed of a plurality of glass balls. When the acetylene gas passes through the packing layer 2, it will be broken into tiny bubbles by the glass balls, thus increasing the gas-liquid contact area, enhancing the absorption effect, and increasing the reaction yield.

[0034] The diameter of the glass balls in the packing layer 2 is 8-12 mm, and the ratio of the height of the packing layer 2 to the inner diameter of the absorption tower 1 is 30-50:7. The large height-to-diameter ratio design increases the contact time of the gas-liquid material, makes the reaction more thorough, and improves the yield of the product.

[0035] It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A tetrabromoethane production device, characterized in that: The invention comprises an absorption tower, wherein a packing layer is arranged in the absorption tower, an acetylene gas inlet is arranged at the lower part of the absorption tower, and a bromine inlet is arranged at the upper part of the absorption tower; The absorption tower is provided with a tetrabromoethane crude product outlet above the acetylene gas inlet, and the gas phase outlet at the top of the absorption tower is connected to the first condenser through a pipeline.

2. A tetrabromoethane production device as claimed in claim 1, characterized in that: A circulation pump is provided at the bottom of the absorption tower, the outlet of the circulation pump is connected to a second condenser through a pipeline, and the outlet of the second condenser is connected to an upper liquid return port of the absorption tower through a pipeline.

3. A tetrabromoethane production device as claimed in claim 2, characterized in that: The absorption tower is a multi-stage absorption tower, which includes a primary absorption tower, a secondary absorption tower and a tertiary absorption tower which are connected in sequence.

4. A tetrabromoethane production device as claimed in claim 3, characterized in that: The top gas phase outlets of the primary absorption tower and the secondary absorption tower are respectively connected to the lower gas phase inlets of the secondary absorption tower and the tertiary absorption tower through pipelines, and the bottom liquid phase outlets of the tertiary absorption tower and the secondary absorption tower are respectively connected to the upper liquid phase inlets of the secondary absorption tower and the primary absorption tower through pipelines; The acetylene gas inlet and the tetrabromoethane crude product outlet are both arranged at the lower part of the primary absorption tower, the bromine inlet is arranged at the upper part of the tertiary absorption tower, the inlet of the first condenser is connected to the gas phase outlet of the tertiary absorption tower, and the outlet of the second condenser is connected to the upper liquid return port of the tertiary absorption tower through a pipeline.

5. A tetrabromoethane production device as claimed in claim 1, characterized in that: The packing layer is a packing layer composed of a plurality of glass balls.

6. A tetrabromoethane production device as claimed in claim 5, characterized in that: The diameter of the glass balls in the packing layer is 8-12 mm.

7. A tetrabromoethane production device as claimed in claim 1, characterized in that: The ratio of the height of the packing layer to the inner diameter of the absorption tower is 30-50:7.

Images