Production method of high-quality tire pyrolysis

The core of the tire pyrolysis oil process is to convert the high molecular polymers in waste tires into liquid hydrocarbon fuels through controllable thermal energy. In this process, the precise control of temperature and the balance of reaction kinetics directly determine the composition distribution and market value of the product.

Temperature is the first factor driving the pyrolysis reaction. When the temperature in the pyrolysis furnace is 300-450℃, the long-chain polymers in the tire rubber (such as natural rubber and synthetic rubber) gradually break into medium molecular weight hydrocarbon compounds. At this time, the liquid oil yield is the highest, but the oil is prone to residual undecomposed colloids and sulfides, resulting in high viscosity and possible generation of polluting gases after combustion. As the temperature rises to 450-600℃, the secondary cracking reaction dominates, and the macromolecular hydrocarbons are further decomposed into light oil (such as gasoline fraction) and combustible gas. The fluidity of the oil is enhanced but the total yield decreases. If the temperature exceeds 600℃, the pyrolysis reaction will completely turn to gasification, the liquid oil almost disappears, and a synthesis gas mainly composed of hydrogen and methane is generated. Therefore, when the target product is fuel oil, the temperature must be strictly controlled within the "liquid window" and the yield and quality must be balanced through a gradient heating strategy.

The impact of reaction kinetics cannot be ignored either. Slow heating (such as 50°C per hour) can extend the "transition period" of the pyrolysis process, allowing the rubber molecules to decompose in an orderly manner and reducing coke formation; while rapid heating (such as microwave pyrolysis technology) accelerates molecular breakage through instantaneous energy input, but may cause uneven product composition due to local overheating. In addition, the insulation time in the pyrolysis furnace needs to be designed in coordination with the temperature - too long a residence time in the high temperature section will aggravate the secondary cracking of the oil phase product, while shortening it may result in incomplete reaction of the raw materials. This dynamic game between temperature and time constitutes the underlying logic of pyrolysis oil process optimization.