A method for preparing granular rubber by continuously extruding desulfurized rubber powder with three screws

Abstract

The invention discloses a method for continuously preparing granular rubber from desulfurized rubber powder by adopting a three-screw extruder, belonging to the field of waste rubber recycling. The desulfurized rubber powder that has been preliminarily and thoroughly cooled is fed into the three-screw extruder through the metering and feeding device. Using the powerful material conveying capacity, shearing, mixing capacity and high production capacity of the three-screw extruder, it can be processed under low temperature conditions. Apply high shear, tension and compression to the desulfurized rubber powder to further destroy the cross-linked network in the desulfurized rubber powder, and reduce the Mooney viscosity of the desulfurized rubber powder while ensuring that the mechanical properties do not decline, and prepare granular Rubber products, replacing the traditional refining machine. The invention uses a three-screw extruder to complete continuously under airtight, low temperature, and high shear conditions, which not only plays the role of traditional refiners in reducing the Mooney viscosity of desulfurized rubber powder, but also has an environmentally friendly, energy-saving, and continuous production process, and the obtained granular rubber products The mechanical properties and Mooney viscosity stability are better than those obtained by traditional refiners.

Description

Technical field: [0001] The invention relates to a new method for reducing the Mooney viscosity of desulfurized rubber powder, in particular to a method for preparing granular rubber by continuously extruding desulfurized rubber powder with three screws, and belongs to the field of waste rubber recycling. Background technique: [0002] With the development of my country's rubber industry, the demand for rubber resources is increasing, and a large amount of imports are required every year. In 2013, the self-sufficiency rate of natural rubber in my country was less than 25%, and the self-sufficiency rate of synthetic rubber was less than 60%. At the same time, waste But rubber is piling up more and more. In 2013, my country produced nearly 300 million waste tires with a weight of about 10.8 million tons. [0003] Scrap tires are industrial hazardous solid waste, insoluble or insoluble polymer materials, which will not disappear naturally for hundreds of years, and pollute soil ...

AI Technical Summary

Problems solved by technology

However, in the open high-speed shearing process of the refiner, it will bring a lot of smoke pollution, which can be said to be the most important source of air pollution in the whole process of desulfurization and regeneration of waste tires

Secondly, each equipment in the traditional refiner preparation process needs to be equipped with an operator. Not only the smoke pollution will endanger the health of the workers, but also the open high-speed refining opportunities will bring great safety hazards to the operators, and work-related injuries occur frequently.

The desulfurized rubber powder is forcibly cut by multiple refining machines and finally rolled out. The temperature of the film will rise above 100°C. Since rubber is a poor conductor of heat, there is not only the risk of spontaneous combustion during storage, but also the door Rebound of Ni viscosity and decline of product mechanical properties

In addition, the traditional method of multiple refining machines still has the disadvantages of high equipment investment cost, high energy consumption and low output

[0004] In order to reduce the environmental pollution caused by the refining machine, large-scale enterprises will use environmentally friendly ventilation and exhaust equipment, and even put the refining unit in a closed room to forcibly suck away the flue gas generated by high-temperature refining and shearing, but this type of environmental protection The effect of long-term use of dust removal equipment is not ideal

In addition, since each refining machine needs to be equipped with a worker, traditional treatment measures cannot solve the air pollution faced by front-line operators

In order to reduce manual participation, Huang Hanxiong et al. (CN201420326527.9) disclosed an automated production line for reclaimed rubber mixing process, using 4 open mills and 2 refiners connected in series, although the number of workers was reduced, the production was improved to a certain extent Efficacy, but the cost of equipment investment has been greatly increased, and the problems of air pollution and potential safety hazards have not been solved

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