阅读说明：本技术 一种单氰胺二聚反应器及其工艺 (Dicyandiamide dimerization reactor and process thereof ) 是由 唐印 莫玉馨 孔德利 宋国天 冯安华 于 2021-08-06 设计创作，主要内容包括：本发明涉及氰胺生产技术领域,具体涉及一种单氰胺二聚反应器及其工艺,包括以下步骤：S1.将流化气通入反应器中,同时打开换热装置；S2.根据流化气的温度和流量调节换热装置温度来控制流化聚合区温度；S3.待反应器流化聚合区温度均衡稳定后通入单氰胺气体；S4.单氰胺气体进入流化聚合区,在催化剂作用下进行二聚反应生成含有双氰胺的混合气体,同时使用换热装置对流化聚合区进行降温；S5.对含有双氰胺的混合气体进行分离得到双氰胺胺。本申请中,换热装置提高了流化聚合区的温度均衡性,通过单独和或分组控制提高了反应器内温度的可控范围和效率。(The invention relates to the technical field of cyanamide production, in particular to a mono-cyanamide dimerization reactor and a process thereof, which comprises the following steps: s1, introducing fluidizing gas into a reactor, and simultaneously opening a heat exchange device; s2, controlling the temperature of the fluidized polymerization zone according to the temperature of the fluidized gas and the temperature of the flow regulating heat exchange device; s3, introducing cyanamide gas after the temperature of a fluidized polymerization zone of the reactor is balanced and stable; s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device; s5, separating the mixed gas containing dicyandiamide to obtain dicyandiamide. In the application, the heat exchange device improves the temperature balance of the fluidized polymerization zone, and improves the controllable range and efficiency of the temperature in the reactor through independent and/or grouped control.)

1. A process for dimerization of cyanamide, which is characterized by comprising the following steps: the method comprises the following steps:

s1, introducing fluidizing gas into a reactor, and simultaneously opening a heat exchange device;

s2, controlling the temperature of the fluidized polymerization zone according to the temperature of the fluidized gas and the temperature of the flow regulating heat exchange device;

s3, introducing cyanamide gas after the temperature of a fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

2. A process for dimerization of cyanamide according to claim 1, wherein: the fluidizing gas temperature in the step S1 is 200-300 ℃.

3. A process for dimerization of cyanamide according to claim 1, wherein: and in the step S1, the pressure in the reactor is controlled to be 0.1-1 MPa.

4. A process for dimerization of cyanamide according to claim 1, wherein: in the step S2, the temperature of the fluidized polymerization zone is controlled to be 130-200 ℃.

5. A process for dimerization of cyanamide according to claim 1, wherein: the temperature of the cyanamide gas introduced in the step S3 is 500-600 ℃.

6. A dicyandiamide dimerization reactor used in a dicyandiamide dimerization process according to any one of claims 1 to 5, comprising a reactor body (1), characterized in that: the reactor is characterized in that a dispersion accelerating device (2) and a heat exchange device (3) are arranged in the reactor body (1).

7. A dicyandiamide dimerization reactor as claimed in claim 6, wherein: the heat exchange device (3) in the reactor body (1) is a heat exchange tube.

8. A dicyandiamide dimerization reactor as claimed in claim 6, wherein: the reactor is characterized in that a process gas ring pipe (4) is arranged on the reactor body (1), and the process gas ring pipe (4) is connected with a plurality of evenly distributed process gas nozzles (5).

9. A dicyandiamide dimerization reactor as claimed in claim 8, wherein: and a circulation separator (6) is arranged in the reactor body (1).

10. A dicyandiamide dimerization reactor as claimed in claim 9, wherein: one end of the circulation separator (6) is connected with a polymerization gas outlet (7), and the polymerization gas outlet extends out of the reactor body (1) and is communicated with the outside.

Technical Field

The invention relates to the technical field of cyanamide production, in particular to a mono-cyanamide dimerization reactor and a process thereof.

Background

The dicyandiamide gas is dimerized under the catalysis to generate dicyandiamide polymer gas, the dicyandiamide gas must reach the dimerization temperature instantly when entering a polymerization reactor, a large amount of reaction heat is instantly generated during the dicyandiamide dimerization reaction, and the polymer gas enters the next working procedure after the dimerization reaction.

In the production process of dicyandiamide, the existing polymerization reaction process is completed in a reaction kettle in a liquid phase state. The heat exchange efficiency of the liquid in the reaction kettle is low, the heat distribution is not uniform, the temperature adjustment and control are slow, the product yield is low, and the automation is difficult to realize.

Disclosure of Invention

The invention aims to provide a dicyandiamide dimerization reactor and a process thereof, which solve the technical problems of low heat exchange efficiency of liquid in a reaction kettle, uneven heat distribution, slow temperature adjustment and control, low product yield and difficult realization of automation in the prior art.

The invention discloses a dicyandiamide dimerization process, which comprises the following steps:

s1, introducing fluidizing gas into a reactor, and simultaneously opening a heat exchange device;

s2, controlling the temperature of the fluidized polymerization zone according to the temperature of the fluidized gas and the temperature of the flow regulating heat exchange device;

s3, introducing cyanamide gas after the temperature of a fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

Further, the temperature of the fluidizing gas in the step S1 is 200-300 ℃.

Further, the pressure in the reactor in the step S1 is controlled to be 0.1-1 MPa.

Further, in the step S2, the temperature of the fluidized polymerization zone is controlled to be 130-200 ℃.

Further, the temperature of the cyanamide gas introduced in the step S3 is 500-600 ℃.

A dicyandiamide dimerization reactor comprises a reactor body, wherein a dispersion speed-increasing device and a heat exchange device are arranged in the reactor body.

Further, the heat exchange device in the reactor body is a heat exchange tube.

Furthermore, a process gas ring pipe is arranged on the reactor body and is connected with a plurality of evenly distributed process gas nozzles.

The process gas nozzle is arranged to guide the process gas and make the process gas form circulation.

Furthermore, a circulation separator is arranged in the reactor body.

Furthermore, one end of the circulation separator is connected with a polymerization gas outlet, and the polymerization gas outlet extends out of the reactor body and is communicated with the outside.

Furthermore, the other end of the circulation separator is connected with a return pipe, and the return pipe penetrates through the distribution plate and extends to the heat exchange device.

By arranging the return pipe, the gasified catalyst can return to the catalytic bed process, so that the catalyst can be conveniently collected.

Further, the number of the loop separators is at least two.

Further, adjacent loop separators are connected in series or in parallel.

By arranging the circulation separators in series or in parallel, the separation efficiency is improved to more than 99 percent.

Compared with the prior art, the invention has the beneficial effects that:

1. the process has high yield, short flow, easy control and high product purity, and can adjust and match with working condition fluctuation in time so as to achieve stable long-period production;

2. the device has the advantages of high heat exchange efficiency, uniform heat distribution, quick temperature adjustment and control, high product yield and high automation degree;

3. the dispersion speed-increasing device can realize fluidization of small gas amount, reduce the diameter of equipment, realize uniform and variable temperature of instantaneous diffusion of process gas by the speed-increasing pipe and the nozzle, and improve the polymerization efficiency and yield;

4. in the application, the heat exchange device improves the temperature balance of the fluidized polymerization zone, and improves the controllable range and efficiency of the temperature in the reactor through single or grouped control;

5. the catalyst circulation separator and the catalyst return pipe enable the catalyst to form a circulation state in the reactor, improve the gas production efficiency of the polymerization gas, improve the flow field distribution effect in the reactor and reduce the consumption of the catalyst.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic view of the reactor structure of the present invention.

In the above drawings, each symbol has the following meaning: 1-reactor body, 2-dispersing speed-raising device, 3-heat-exchanging device, 4-process gas loop, 5-process gas nozzle, 6-circulation separator, 7-polymerization gas outlet and 8-reflux pipe.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention.

A specific structure of a dicyandiamide dimerization reactor is shown in figure 1, and the reactor comprises a reactor body 1, wherein a dispersion speed-raising device 2 and a heat exchange device 3 are arranged in the reactor body 1, the heat exchange device 3 in the reactor body 1 is a heat exchange tube, a process gas loop 4 is arranged on the reactor body 1, the process gas loop 4 is connected with a plurality of uniformly distributed process gas nozzles 5, a loop separator is arranged in the reactor body 1, one end of the loop separator 6 is connected with a polymerization gas outlet 7, the polymerization gas outlet extends out of the reactor body 1 to be communicated with the outside, the other end of the loop separator 6 is connected with a return pipe 8, and the return pipe 8 penetrates through a distribution plate to extend to the heat exchange device 3.

Example 1

The dicyandiamide dimerization process of the device adopted in the embodiment comprises the following steps:

s1, introducing 280 ℃ fluidization gas into a reactor, controlling the pressure in the reactor to be 0.3MPa, and simultaneously opening a heat exchange device;

s2, controlling the temperature of a fluidized polymerization zone to be 130-200 ℃ according to the temperature of the fluidized gas and the temperature of the flow adjusting heat exchange device;

s3, introducing 500-600 ℃ cyanamide gas after the temperature of the fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

The dicyandiamide content in the product is more than 90%.

Example 2

In this embodiment, as a preferred embodiment of the present invention, a dicyandiamide dimerization process includes the following steps:

s1, introducing 250 ℃ fluidizing gas into a reactor, controlling the pressure in the reactor to be 0.3MPa, and simultaneously opening a heat exchange device;

s2, controlling the temperature of a fluidized polymerization zone to be 130-200 ℃ according to the temperature of the fluidized gas and the temperature of the flow adjusting heat exchange device;

s3, introducing 500-600 ℃ cyanamide gas after the temperature of the fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

The dicyandiamide content in the product is more than 90%.

Example 3

In this embodiment, as a preferred embodiment of the present invention, a dicyandiamide dimerization process includes the following steps:

s1, introducing 250 ℃ fluidizing gas into a reactor, controlling the pressure in the reactor to be 0.6MPa, and simultaneously opening a heat exchange device;

s2, controlling the temperature of a fluidized polymerization zone to be 130-200 ℃ according to the temperature of the fluidized gas and the temperature of the flow adjusting heat exchange device;

s3, introducing 500-600 ℃ cyanamide gas after the temperature of the fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

The dicyandiamide content in the product is more than 90%.

Example 4

In this embodiment, as a preferred embodiment of the present invention, a dicyandiamide dimerization process includes the following steps:

s1, introducing fluidizing gas at 200 ℃ into a reactor, controlling the pressure in the reactor to be 0.3MPa, and simultaneously opening a heat exchange device;

s2, controlling the temperature of a fluidized polymerization zone to be 130-200 ℃ according to the temperature of the fluidized gas and the temperature of the flow adjusting heat exchange device;

s3, introducing 500-600 ℃ cyanamide gas after the temperature of the fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

The dicyandiamide content in the product is more than 90%.

Example 5

In this embodiment, as a preferred embodiment of the present invention, a dicyandiamide dimerization process includes the following steps:

s1, introducing fluidizing gas at 200 ℃ into a reactor, controlling the pressure in the reactor to be 0.5MPa, and simultaneously opening a heat exchange device;

s2, controlling the temperature of a fluidized polymerization zone to be 130-200 ℃ according to the temperature of the fluidized gas and the temperature of the flow adjusting heat exchange device;

s3, introducing 500-600 ℃ cyanamide gas after the temperature of the fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

The dicyandiamide content in the product is more than 90%.

Example 6

In this embodiment, as a preferred embodiment of the present invention, a dicyandiamide dimerization process includes the following steps:

s1, introducing 300 ℃ fluidizing gas into a reactor, controlling the pressure in the reactor to be 0.1MPa, and simultaneously opening a heat exchange device;

s2, controlling the temperature of a fluidized polymerization zone to be 130-200 ℃ according to the temperature of the fluidized gas and the temperature of the flow adjusting heat exchange device;

s3, introducing 500-600 ℃ cyanamide gas after the temperature of the fluidized polymerization zone of the reactor is balanced and stable;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

The dicyandiamide content in the product is more than 90%.

Example 7

In this embodiment, as a preferred embodiment of the present invention, a dicyandiamide dimerization process includes the following steps:

s1, introducing 280 ℃ fluidization gas into a reactor, controlling the pressure in the reactor to be 0.3MPa, and simultaneously opening a heat exchange device;

s2, fully opening the heat exchange device when the temperature and the flow of the gas to be fluidized are stable;

s3, introducing 500-600 ℃ cyanamide gas after fluidization of the fluidization area is normal;

s4, allowing the cyanamide gas to enter a fluidized polymerization zone, carrying out dimerization reaction under the action of a catalyst to generate mixed gas containing dicyandiamide, and simultaneously cooling the fluidized polymerization zone by using a heat exchange device;

s5, separating the mixed gas containing the dicyandiamide to obtain the dicyandiamide.

The dicyandiamide content in the product is more than 70%.

The above embodiments are just exemplified in the present embodiment, but the present embodiment is not limited to the above alternative embodiments, and those skilled in the art can obtain other various embodiments by arbitrarily combining with each other according to the above embodiments, and any other various embodiments can be obtained by anyone in light of the present embodiment. The above detailed description should not be construed as limiting the scope of the present embodiments, which should be defined in the claims, and the description should be used for interpreting the claims.