Why a Dewaxing Tank Is Required for Waste Plastic Pyrolysis Oil Production

Wax removal tanks are essential equipment for waste plastic oil refining, mainly used to solve pipeline blockages, potential safety hazards, poor oil quality and frequent equipment maintenance caused by wax substances.

1. Source and Hazards of Wax

Waste plastics (especially PE and PP) will produce a large amount of long-chain alkanes with carbon numbers between C₂₀ and C₄₀ during pyrolysis. These substances exist in solid or semi-solid wax form at normal temperature. If not removed in advance, it will lead to the following problems:

1. Potential safety risks: Wax condenses and accumulates inside pipelines, narrowing or even blocking pipes. This causes pressure buildup in the reactor and brings major explosion risks.

2. Poor oil quality: The finished oil has a high pour point. It becomes viscous or solidifies at low temperatures, appears turbid and forms precipitates easily, and can only be sold as low-cost boiler fuel.

3. Frequent production shutdowns: Pipeline blockages require regular shutdowns for wax cleaning, resulting in high maintenance costs and low production efficiency.

   
   

2. Working Principle of Dewaxing Tank

The dewaxing tank is installed between the buffer tank and condenser. High-temperature oil and gas first flows into the dewaxing tank, where cooling water or heat conduction oil lowers the temperature below the wax solidification point. The wax components condense and adhere to the tank wall and are cleaned periodically. The dewaxed oil and gas then enters the condenser to produce clear finished oil with low solidification point.

3. Core Advantages of Equipping a Dewaxing Tank

1. Ensure production safety: It intercepts wax in advance to prevent pipe blockage and pressure rise, enabling continuous and stable operation of the production line.

2. Greatly improve oil quality: The pour point and solidification point of oil are reduced to below -10℃. The oil is clear, stable and free of precipitates, and can work normally in low-temperature environments.

3. Increase economic benefits: The refined oil can be sold at a much higher price and used as diesel blending component or high-grade industrial fuel. The separated wax can also be processed into industrial paraffin wax for additional revenue.

4. Cut maintenance costs: It effectively reduces wax cleaning frequency for pipelines and condensers, extends service life of equipment and avoids losses caused by frequent shutdowns.

   
   

Summary

The dewaxing tank is a standard and critical device for waste plastic pyrolysis oil production. Without it, the production line cannot operate safely and continuously, and the final oil product will lack market competitiveness. Equipping a dewaxing tank comprehensively optimizes production safety, product quality, economic benefit and operational stability.