Safety valve for polypropylene loop reactor

Abstract

The invention relates to the technical field of polypropylene reaction equipment, in particular to a safety valve for a polypropylene loop reactor. In the safety valve, the entrance of a valve seat is in an arc shape; a seal surface and a horizontal surface of the valve seat form an angle of 45 degrees; the entrance of a cavity is provided with a press ring; a valve clack is fixedly connected to the press ring; a press rod is arranged above the valve clack; by a structure, a medium in the loop reactor can smoothly pass through the valve seat of the safety valve and is prevented from being collected and crystallized at the entrance of the safety valve to block a pipeline; the safety valve is relieved and rapidly meets the requirement so as to ensure that the safety valve has enough relieving capability; the safety valve can still stably run in an environment of relatively high back pressure; a seal structure of the safety valve for the loop reactor is a soft seal structure, so the tightness of the safety valve is ensured under the conditions of the existence of solid particles in the medium and high pressure; and the seal structure is easy and convenient to disassemble and assemble, a failure seal ring can be simply and conveniently disassembled and replaced, and repair and maintenance are facilitated.

Description

technical field [0001] The invention belongs to the technical field of polypropylene device reaction, and in particular relates to a safety valve. Background technique [0002] The currently widely used polypropylene production technology is the liquid-phase bulk method, and most of this technology uses a loop reactor as the reaction equipment. However, the polypropylene reaction process requires a relatively coherent circulation process, and local accumulation and wall hanging must be avoided. The sealing pair of a conventional safety valve is a certain distance from the valve inlet. When installed on the equipment, it will be in the area between the inlet and the sealing pair. A medium "flow dead zone" is formed, causing the medium to stagnate in this area. If a safety valve with a conventional structure is installed on the loop reactor, due to the characteristics of the polypropylene medium, polypropylene particles will accumulate in the "flow dead zone", block the inlet...

AI Technical Summary

Problems solved by technology

However, the polypropylene reaction process requires a relatively coherent circulation process, and local accumulation and wall hanging must be avoided. The sealing pair of a conventional safety valve is a certain distance from the valve inlet. When installed on the equipment, it will be in the area between the inlet and the sealing pair. Form a medium "flow dead zone", causing the medium to stagnate in this area

If a safety valve with a conventional structure is installed on the loop reactor, due to the characteristics of the polypropylene medium, polypropylene particles will accumulate in the "flow dead zone", block the inlet, and affect the normal operation of the equipment

Moreover, after the safety valve is opened, the solid particles in the medium will impact the bellows, causing the bellows to work effectively and unable to balance the pressure.

Therefore, the inlet, flow channel structure and back pressure isolation structure of the conventional safety valve cannot meet the actual needs of the polypropylene loop reactor device.

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