C12-14 tertiary amine preparation system

Abstract

The utility model relates to the field of chemical production, and provides a C12-14 tertiary amine preparation system. Comprising an amination kettle, a coil heat exchanger is installed in the amination kettle, a gas outlet is formed in the top of the amination kettle and connected with the bottom of a separation tower through a pipeline, a gas outlet in the top of the separation tower is connected with a condenser through a pipeline, and a gas outlet of the condenser is connected with a gas suction port of a gas compressor through a pipeline. And an exhaust port of the gas compressor is connected with a gas distribution pipe at the bottom in the amination kettle through a gas pipeline. Gas raw materials which are not completely reacted in the reaction process and uncondensed raw materials are compressed through a gas compressor and then are fed into the bottom of an amination kettle together with the gas raw material dimethylamine, uniform spraying is performed through a distribution pipe at the bottom of the amination kettle, and turning of the raw materials is formed in the amination kettle while spraying is performed; gas raw materials, solid catalysts and liquid raw materials are in full contact, and the reaction efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the field of chemical production, in particular to a C12-14 tertiary amine preparation system. Background Art

[0002] C12-14 tertiary amine is generally used to make quaternary ammonium salt cationic surfactants and zwitterionic surfactants. Its preparation process is to generate C12-14 tertiary amine products by heating under the catalytic action of solid catalyst particles with fatty alcohol, dimethylamine gas and a small amount of hydrogen. The C12-14 tertiary amine products are evaporated in the form of steam, and the steam contains evaporated raw materials, etc., which need to be separated by a separation tower. The raw materials at the separation can be returned to the amination kettle for further reaction to save the cost of raw materials.

[0003] Since the reaction process involves the reaction between liquid and gaseous raw materials and a solid catalyst, in order to improve the reaction efficiency, a stirring method is adopted in a conventional amination reactor to ensure sufficient mixing reaction between the three forms of raw materials. The stirring method can increase the uniformity of the contact between the liquid raw material and the catalyst, but cannot fully guarantee the contact time between the gaseous dimethylamine and the raw material. Summary of the invention

[0004] In order to ensure sufficient mixing of raw materials during the preparation of C12-14 tertiary amines, thereby improving the yield of finished products, the utility model aims to provide a C12-14 tertiary amine preparation system.

[0005] The technical solution adopted by the utility model is:

[0006] A C12-14 tertiary amine preparation system comprises an amination kettle, wherein a coil heat exchanger is installed in the amination kettle, a circulating heat exchange medium is passed through the coil heat exchanger, raw materials are added into the amination kettle, a gas outlet is arranged at the top of the amination kettle, the gas outlet is connected to the bottom of a separation tower through a pipeline, the gas outlet at the top of the separation tower is connected to a condenser through a pipeline, the gas outlet of the condenser is connected to the air intake of a gas compressor through a pipeline, the exhaust port of the gas compressor is connected to a gas distribution pipe at the bottom of the amination kettle through a gas pipeline, a raw material input branch is connected to the gas pipeline, the gas distribution pipe is located at the center of the bottom of the amination kettle and below the raw material liquid level; the gas distribution pipe comprises a guide pipe and a uniform distribution pipe, the uniform distribution pipe is an annular circular pipe, the uniform distribution pipe is horizontally arranged, a circle of uniformly distributed air holes is arranged on the top surface of the uniform distribution pipe, one side of the uniform distribution pipe is connected to the guide pipe through a joint, the guide pipe is vertically arranged and connected to the gas inlet at the top of the amination kettle, and the gas inlet is connected to the exhaust port of the gas compressor through the gas pipeline.

[0007] Furthermore, the condenser includes two stages of shell and tube heat exchangers arranged in series, circulating cooling water passes through the tube side of each shell and tube heat exchanger, the steam in the separation tower enters the shell side of the first-stage shell and tube heat exchanger, the condensate outlets of the two-stage shell and tube heat exchangers are respectively connected to the separators through pipelines, the gas outlet of the shell side of the first-stage shell and tube heat exchanger is connected to the shell side of the second-stage shell and tube heat exchanger through a pipeline, and the gas outlet of the second-stage shell and tube heat exchanger is connected to the gas compressor through a pipeline.

[0008] Furthermore, the bottom of the separator is connected to the water collection tank through a pipeline, and the top of the separator is connected to the top of the separation tower through an overflow pipeline.

[0009] Furthermore, the bottom of the separation tower is connected to the material inlet at the bottom of the amination kettle through a pipeline.

[0010] Furthermore, a distributor is installed in the amination kettle. The distributor is a tapered cylinder. The inner diameter of the upper opening of the distributor is larger than the inner diameter of the lower opening. A sieve plate is installed at the lower opening of the distributor. The sieve plate is provided with evenly distributed sieve holes.

[0011] Furthermore, a plurality of distributors arranged at equal intervals in the vertical direction are arranged in the amination kettle, the distributors are arranged coaxially with the amination kettle, and the distributors are fixedly connected to the inner wall of the amination kettle through ribs.

[0012] Furthermore, the heat exchange medium in the coil heat exchanger is hot oil, the bottom of the amination kettle is provided with an oil inlet connected to the coil heat exchanger, and the middle of the amination kettle is provided with an oil outlet connected to the coil heat exchanger.

[0013] Furthermore, the separation tower is equipped with multiple groups of packings.

[0014] After adopting the above technical scheme, the beneficial effects of the utility model are:

[0015] The gas raw materials that are not completely reacted and the raw materials that are not condensed during the reaction are compressed by a gas compressor and sent to the bottom of the amination kettle together with the gas raw material dimethylamine, and are uniformly sprayed through a distribution pipe at the bottom of the amination kettle. While spraying, the raw materials are tumbling in the amination kettle, and the gas raw materials, solid catalysts and liquid raw materials are fully contacted, thereby improving the reaction efficiency. The distribution device can delay the residence time of the gas in the amination kettle, and the bubbles formed by the gas are further dispersed and contacted with the raw materials during the rising process of the bubbles, which effectively increases the effective reaction time and improves the yield of the finished product; the unreacted raw materials are forced to circulate through the gas compressor and repeatedly enter the amination kettle for reaction, thereby improving the utilization rate of the raw materials and reducing the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is the reaction principle diagram of the utility model.

[0017] Figure 2 It is a schematic diagram of the structure of the amination reactor.

[0018] Figure 3 This is the AA view.

[0019] In the figure: an amination kettle 1, a separation tower 2, a condenser 3, a separator 4, an air compressor 5, a coil heat exchanger 6, a guide pipe 7, a uniform distribution pipe 8, a distributor 9, a sieve plate 10, and an overflow pipe 11. DETAILED DESCRIPTION

[0020] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings:

[0021] like Figure 1 As shown, a C12-14 tertiary amine preparation system is composed of an amination kettle 1, a separation tower 2, a condenser 3, a separator 4, an air compressor 5 and related pipelines and valves, and is used for the preparation of C12-14 tertiary amines.

[0022] The top of the amination kettle 1 is provided with a material inlet, a gas inlet, a gas outlet and a manhole, and the bottom of the amination kettle is provided with a sewage outlet. A coil heat exchanger 6 is installed in the amination kettle 1, and hot oil above 200°C is passed through the coil heat exchanger 6 to ensure the reaction temperature. The bottom of the amination kettle 1 is provided with an oil inlet connected to the coil heat exchanger, and the middle of the amination kettle is provided with an oil outlet connected to the coil heat exchanger.

[0023] A gas distribution pipe is installed in the amination kettle 1, and the gas distribution pipe includes a guide pipe 7 and a uniform distribution pipe 8. The uniform distribution pipe 8 is an annular circular pipe, and the uniform distribution pipe 8 is horizontally arranged at the center of the bottom of the amination kettle 1. A circle of uniformly distributed air holes is arranged on the top surface of the uniform distribution pipe 8. One side of the uniform distribution pipe 8 is connected to the guide pipe 7 through a joint. The guide pipe 7 is vertically arranged along the inner wall of the amination kettle 1, and the upper end of the guide pipe 7 is connected to the gas inlet at the top of the amination kettle 1.

[0024] Two distributors 9 are installed in the amination kettle 1, and the two distributors 9 are arranged vertically up and down. The distributor 9 is a cylindrical body with a taper, and the distributor 9 is coaxially arranged with the amination kettle 1, and the distributor 9 is fixedly connected to the inner wall of the amination kettle 1 through ribs. The inner diameter of the upper opening of the distributor 9 is larger than the inner diameter of the lower opening, and a sieve plate 10 is installed at the lower opening of the distributor 9, and the sieve plate is provided with evenly distributed sieve holes.

[0025] The raw material fatty alcohol is added into the amination kettle 1 from the material inlet, and the catalyst is deposited at the bottom of the amination kettle. The catalyst is a solid particle catalyst. The dimethylamine gas enters the amination kettle 1 from the gas inlet. Under the heating of the coil heat exchanger 6, the reaction generates C12-14 tertiary amines. The finished product and the raw material evaporate at high temperature to form steam, and the steam enters the separation tower 2 from the bottom of the separation tower 2 through the pipeline from the gas outlet. Multiple groups of packings are installed from bottom to top in the separation tower. At the same time, the separation tower 2 maintains a high temperature of about 200°C through heat exchange. Most of the C12-14 tertiary amine steam liquefies after contacting with the packing in the separation tower 2 and is collected at the bottom of the separation tower. The bottom of the separation tower 2 is connected to the material inlet at the top of the amination kettle 1 through a pipeline, and can be controlled by a valve to continue to circulate back to the amination kettle. Fatty alcohol, dimethylamine and generated water enter the condenser 3 from the top of the separation tower for condensation.

[0026] The condenser 3 is composed of two stages of shell and tube heat exchangers arranged in series. Circulating cooling water passes through the tube side of each shell and tube heat exchanger. The steam in the separation tower enters the shell side of the first-stage shell and tube heat exchanger. The gas outlet of the shell side of the first-stage shell and tube heat exchanger is connected to the shell side of the second-stage shell and tube heat exchanger through a pipeline. Most of the steam is condensed in the first-stage shell and tube heat exchanger, and a small amount of steam and non-condensable gas enters the second-stage shell and tube heat exchanger. The condensate outlets of the two-stage shell and tube heat exchangers are respectively connected to the separator 4 through pipelines, and the non-condensable gas outlet in the second-stage shell and tube heat exchanger enters the gas compressor 4 through a pipeline.

[0027] The separator 4 is used to receive the condensate, which includes water generated by the reaction, the finished product and the fatty alcohol raw material. The condensate is layered in the separator 4, and the oil layer at the top flows into the separation tower 2 from the overflow pipe 11 for circulation and separation, while the water phase at the bottom is discharged into the water collection tank through a pipe.

[0028] The non-condensable gas in the second-stage shell and tube heat exchanger is mainly diethylamine and a small amount of hydrogen. After entering from the air intake port of the gas compressor 5, it is compressed. The compressed gas is connected to the gas inlet of the amination kettle 1 through a gas pipeline and enters the distribution pipe at the bottom of the amination kettle to continue to react. At the same time, the diethylamine gas raw material is connected to the gas pipeline through a pipeline and enters the amination kettle 1 together with the compressed gas to react, thereby realizing the recovery cycle of the raw materials.

Claims

1. A system for preparing C12-14 tertiary amines, comprising an amination kettle, a coil heat exchanger is installed in the amination kettle, a circulating heat exchange medium is passed through the coil heat exchanger, and raw materials are added to the amination kettle, characterized in that: A gas outlet is provided on the top of the amination kettle, and the gas outlet is connected to the bottom of the separation tower through a pipeline. The gas outlet on the top of the separation tower is connected to a condenser through a pipeline. The gas outlet of the condenser is connected to the air intake of the gas compressor through a pipeline. The exhaust port of the gas compressor is connected to the gas distribution pipe at the bottom of the amination kettle through a gas pipeline. The gas pipeline is connected to a raw material input branch. The gas distribution pipe is located at the center of the bottom of the amination kettle and below the raw material liquid level; the gas distribution pipe includes a guide pipe and a uniformly distributed pipe. The uniformly distributed pipe is an annular circular pipe. The uniformly distributed pipe is horizontally arranged. A circle of uniformly distributed air holes is arranged on the top surface of the uniformly distributed pipe. One side of the uniformly distributed pipe is connected to the guide pipe through a joint. The guide pipe is vertically arranged and connected to the gas inlet at the top of the amination kettle. The gas inlet is connected to the exhaust port of the gas compressor through a gas pipeline.

2. A C12-14 tertiary amine preparation system according to claim 1, characterized in that: The condenser comprises two stages of shell and tube heat exchangers arranged in series, circulating cooling water passes through the tube side of each shell and tube heat exchanger, the steam in the separation tower enters the shell side of the first-stage shell and tube heat exchanger, the condensate outlets of the two-stage shell and tube heat exchangers are respectively connected to the separators through pipelines, the gas outlet of the shell side of the first-stage shell and tube heat exchanger is connected to the shell side of the second-stage shell and tube heat exchanger through a pipeline, and the gas outlet of the second-stage shell and tube heat exchanger is connected to the gas compressor through a pipeline.

3. A C12-14 tertiary amine preparation system according to claim 2, characterized in that: The bottom of the separator is connected to the water collection tank through a pipeline, and the top of the separator is connected to the top of the separation tower through an overflow pipeline.

4. A C12-14 tertiary amine preparation system according to claim 2, characterized in that: The bottom of the separation tower is connected to the material inlet at the bottom of the amination kettle through a pipeline.

5. A C12-14 tertiary amine preparation system according to claim 1, characterized in that: A distributor is installed in the amination kettle. The distributor is a cone-shaped cylinder. The inner diameter of the upper opening of the distributor is larger than the inner diameter of the lower opening. A sieve plate is installed at the lower opening of the distributor. The sieve plate is provided with evenly distributed sieve holes.

6. A C12-14 tertiary amine preparation system according to claim 5, characterized in that: A plurality of distributors arranged at equal intervals in the vertical direction are arranged in the amination kettle, the distributors are arranged coaxially with the amination kettle, and the distributors are fixedly connected to the inner wall of the amination kettle through ribs.

7. A C12-14 tertiary amine preparation system according to claim 1, characterized in that: The heat exchange medium in the coil heat exchanger is hot oil. The bottom of the amination kettle is provided with an oil inlet connected to the coil heat exchanger, and the middle of the amination kettle is provided with an oil outlet connected to the coil heat exchanger.

8. A C12-14 tertiary amine preparation system according to claim 1, characterized in that: The separation tower is equipped with multiple groups of packings.

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