A waste plastic molten salt pyrolysis device

Abstract

The invention discloses a waste plastic molten salt cracking device. The waste plastic molten salt cracking device comprises a cracking furnace, the first end of the cracking furnace is provided with a molten salt outlet, the second end of the cracking furnace is provided with a molten salt inlet, a rotor feeder with a sealing function is arranged on an upper wall of the cracking furnace, a distributor is arranged on the position, close to the feeder, of the cracking furnace, the distributor is connected with a molten salt pump through a salt conveying pipe, all branch pipes of the distributor penetrate through the cracking furnace, a molten salt spray pipe is installed at the lower end of each branch pipe, the cracking furnace is provided with a tapered molten salt settling pond, the highest position of the upper wall of the cracking furnace is provided with a cracking gas outlet, and the molten salt outlet is connected with a molten salt furnace through a pipeline; the molten salt furnace is connected with the molten salt pump, one part of molten salt is sent to the second end of the sealed cracking furnace by the molten salt pump through the salt conveying pipe, and the other part of the molten salt is sent into the distributor. Due to the fact that the distributor is arranged, the heat transfer surface area is increased, the structure of the waste plastic cracking device is simplified, and the cracking efficiency is improved.

Description

technical field [0001] The invention relates to a waste plastic molten salt pyrolysis device for rapidly pyrolyzing waste plastics by utilizing the heat of high-temperature molten salt and a waste plastic molten salt pyrolysis method using the device. Background technique [0002] With the development of society and the advancement of science and technology, various plastic products have entered various fields of social life and play a huge role. However, the amount of plastic waste is increasing day by day and is not easy to degrade, causing white pollution. [0003] At present, the main method of chemical recycling of waste plastics is cracking and oiling. Its cracking mechanism is similar to thermal cracking and catalytic cracking in petrochemical industry. Since they decompose macromolecular substances into small molecular substances either under the action of thermal energy or under the action of catalysts, the methods used are thermal cracking and catalytic cracking. ...

AI Technical Summary

Problems solved by technology

The fixed bed reactor is generally heated by salt bath or inert heat carrier, but it will bring problems such as uneven heating, insufficient reaction, etc., and low cracking efficiency

In the fluidized bed reactor, the heat carrier is directly mixed with the waste plastic, but it will cause problems such as catalyst sintering, clogging and inability to fully contact the raw material in the entire reactor, resulting in a large amount of residual oil due to coking

[0005] Aiming at the problems of coking, uneven heat transfer, and low pyrolysis efficiency in traditional waste plastic pyrolysis devices, CN102260515A discloses a waste plastic pyrolysis treatment method and device. Low density, heated by direct contact with molten salt when moving upward under the action of buoyancy

[0006] However, if the waste plastics are sent to the bottom of the molten salt pool by means of spiral mechanical mechanisms, then these mechanisms will work at high temperatures, and the reliability is not high, or they must be made of high-temperature alloy steel, and the cost is very high, especially when the plastic enters from the pusher. In the molten salt pool, it is a plastic mass with a small contact surface with the molten salt, which is not conducive to the heat transfer process. In order to complete the thermal cracking of the plastic, the depth of the molten salt pool must be increased; A lot of screw pushing mechanisms are placed in the salt pond, resulting in a complicated structure

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