Polymerizing kettle for preventing self-polymerization of PVC (Polyvinyl Chloride) resin at blasting opening

Abstract

The utility model discloses a polymerization kettle capable of preventing PVC (polyvinyl chloride) resin from self-aggregation at a blasting opening, belongs to the technical field of chemical production, and solves the problems that an anti-sticking agent cannot be sprayed at the blasting opening of the existing polymerization kettle, the PVC resin can be self-aggregated at the blasting opening during reaction, the blasting opening is blocked, and safety accidents are caused. The device comprises a nitrogen pipeline, the nitrogen pipeline is arranged between an inlet valve of a blasting pipe and a blasting piece, and a control valve is arranged on the nitrogen pipeline. The device is stable in operation, effectively reduces the self-aggregation phenomenon of the blasting pipeline of the polymeric kettle, reduces the cleaning frequency of the blasting pipeline, reduces the manual labor force, reduces the production cost, and has very high popularization value.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical production, and particularly relates to a polymerization kettle capable of preventing PVC resin from self-polymerizing at a blasting hole. Background Art

[0002] In the production of polyvinyl chloride (PVC) using the calcium carbide process, most polymerization units utilize suspension polymerization. Using vinyl chloride as the raw material and desalted water as the suspension medium, initiators, dispersants, and other additives are added. Polyvinyl chloride resin is produced under stirring at a specific pressure, temperature, and speed. During the polymerization process, PVC resin adheres to the inner walls of the polymerization kettle and the surfaces of the kettle components. If not promptly removed, it will gradually accumulate, causing the PVC resin to continuously fill gaps and form tight bonds. This, coupled with slight plasticization during the heating process, forms a sticky residue, which reduces the heat transfer coefficient and the kettle's heat transfer capacity, hindering the removal of reaction heat.

[0003] At present, spraying an anti-sticking agent on its surface is a common method. The anti-sticking agent forms a polymer under the atomization action of high-temperature steam, condenses on the wall of the polymerization kettle and the cooling baffle, and forms an oleophobic and hydrophilic film. Vinyl chloride oil droplets are used to separate them from the kettle wall during the polymerization reaction. However, the blasting nozzle of the polymerization kettle cannot be sprayed, resulting in the gradual accumulation of self-polymers at the blasting nozzle during the reaction of the polymerization kettle, forming large pieces of self-polymers that block the blasting pipe of the polymerization kettle. In the case of out-of-control pressure in the polymerization kettle, the pressure in the polymerization kettle cannot be released from the blasting disc in time, posing a major safety hazard. Manual cleaning is required after the polymerization kettle has been running for 50 cycles, resulting in a large amount of manual labor, affecting the continuous production of the polymerization kettle and reducing the production efficiency of the polymerization kettle. Utility Model Content

[0004] The utility model provides a polymerization kettle capable of preventing PVC resin from self-aggregating at a blasting hole, so as to solve the problem that the blasting pipe of the existing polymerization kettle cannot be sprayed with an anti-sticking kettle agent, and the PVC resin self-aggregates at the blasting hole during the reaction, thereby blocking the blasting hole and causing safety accidents.

[0005] The technical solution of the utility model is: a polymerization kettle for preventing PVC resin from self-polymerizing at a bursting hole, comprising a polymerization kettle, a bursting pipe being provided on the top of the polymerization kettle, a bursting pipe inlet valve, a bursting disc and a bursting pipe outlet valve being provided on the bursting pipe, and a nitrogen pipe being installed between the bursting pipe inlet valve and the bursting disc, and a control valve being provided on the nitrogen pipe.

[0006] As a further improvement of the present invention, a pipeline pressure gauge is further provided on the nitrogen pipeline, and the pipeline pressure gauge and the control valve are connected via a signal.

[0007] The beneficial effects of this utility model are as follows: by installing a nitrogen pipeline in the polymerization kettle blasting pipeline, nitrogen is introduced through the pipeline into the bottom of the bursting disc and the blasting pipeline. This inert nitrogen gas flow suppresses the self-aggregation of PVC resin in the blasting pipeline, while also increasing the frequency of cleaning the self-aggregates at the blasting opening from 50 kettles to 500 kettles. The utility model has stable operation, effectively reduces the self-aggregation phenomenon in the polymerization kettle blasting pipeline, reduces labor and production costs, and has strong promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic structural diagram of the utility model.

[0009] In the figure: 1-polymerization kettle, 2-agitator, 3-auxiliary agent pipeline valve, 4-desalted water / vinyl chloride monomer pipeline valve, 5-anti-adhesion agent spray pipeline valve, 6-polymerization kettle discharge pipeline valve, 7-polymerization kettle recovery pipeline regulating valve, 8-blasting pipeline, 9-blasting pipe inlet valve, 10-blasting disc, 11-blasting pipe outlet valve; 12-nitrogen pipeline; 13-control valve, 14-pressure gauge. DETAILED DESCRIPTION

[0010] The present invention will be described in further detail below with reference to the accompanying drawings and specific implementations.

[0011] like Figure 1 As shown, a polymerization kettle for preventing PVC resin from self-polymerizing at a bursting hole comprises a polymerization kettle 1. A bursting pipe 8 is provided on the top of the polymerization kettle 1. The bursting pipe 8 is provided with a bursting pipe inlet valve 9, a fragment 10 and a bursting pipe outlet valve 11.

[0012] A polymerization kettle for preventing PVC resin from self-polymerizing at a bursting hole also includes a nitrogen pipeline 12 installed between a bursting tube inlet valve 9 and a bursting disc 10, and a control valve 13 is provided on the nitrogen pipeline 12.

[0013] A pipeline pressure gauge 14 is also provided on the nitrogen pipeline 12 , and the pipeline pressure gauge 14 is connected to the control valve 13 via a signal.

[0014] When in use, first close the polymerizer recovery pipeline regulating valve 7, the polymer discharge pipeline valve 6 and the bursting tube inlet valve 9, start the agitator 2, and after the agitator 2 runs stably, open the anti-adhesion agent spraying pipeline valve 5 to spray the inner wall of the polymerizer 1. After spraying for 5 minutes, close the anti-adhesion agent spraying pipeline valve 5, open the desalted water / vinyl chloride monomer pipeline valve 4, and add the pre-proportioned vinyl chloride monomer and desalted water to the polymerizer 1. The amount added each time is automatically set by the program of the desalted water / vinyl chloride monomer pipeline valve 4. Open the auxiliary agent pipeline valve 3, add a small amount of auxiliary agent to the polymerizer 1 to start the reaction of the materials in the polymerizer 1, and at the same time open the bursting tube inlet. Open the outlet valve 9 and the bursting pipe outlet valve 11. After the reaction in the polymerization kettle 1 starts to stabilize, close the agent pipeline valve 3, the desalted water / vinyl chloride monomer pipeline valve 4 and the anti-adhesion agent spray pipeline valve 5, open the polymerization kettle discharge pipeline valve 6 and the control valve 13, and allow nitrogen to be continuously introduced into the bottom of the bursting disc and the bursting pipeline 8. Nitrogen is introduced into the bottom of the bursting disc 10 and the bursting pipeline 8 through the nitrogen pipeline 8, so that the flow of inert gas nitrogen suppresses the self-polymerization of the PVC resin in the bursting pipeline 8. By adjusting the control valve 13, the nitrogen pipeline pressure gauge 14 stably displays 10kPa, and the polymerization kettle recovery pipeline regulating valve 7 is opened to ensure that the pressure in the polymerization kettle 1 is stable and operates normally.

Claims

1. A polymerization kettle for preventing PVC resin from self-polymerizing at a bursting hole, comprising a polymerization kettle (1), a bursting pipe (8) provided on the top of the polymerization kettle (1), a bursting pipe inlet valve (9), a fragment (10) and a bursting pipe outlet valve (11), characterized in that: It also includes a nitrogen pipeline (12), which is installed between the bursting tube inlet valve (9) and the bursting disc (10), and a control valve (13) is provided on the nitrogen pipeline (12).

2. A polymerization kettle for preventing PVC resin from self-polymerizing at a blasting opening according to claim 1, characterized in that: The nitrogen pipeline (12) is also provided with a pipeline pressure gauge (14), and the pipeline pressure gauge (14) and the control valve (13) are connected via a signal.

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