Analysis of Pyrolysis Oil Refining Equipment Configurations and Components

Pyrolysis oil refining equipment is a critical system used to purify and upgrade the crude oil generated from the pyrolysis of waste materials such as tires and plastics. Depending on processing scale, feedstock characteristics, and target product specifications, these systems employ diverse technical approaches regarding their physical configuration and system architecture.

Classification of Equipment Configurations

Structurally, pyrolysis oil refining equipment falls into two main categories: skid-mounted units and complete production lines.

Skid-mounted units feature a modular design that integrates core components—such as reaction vessels, condensers, and buffer tanks—onto a single frame, offering a compact footprint and ease of transport and installation. Typically handling between 100 kg and 500 kg per batch, these units are ideal for small-scale projects or experimental validation phases. Their primary advantage lies in being pre-assembled and pre-commissioned at the factory, allowing for rapid on-site deployment; this makes them particularly suitable for scenarios involving decentralized feedstock supplies or projects requiring quick verification of process feasibility during the initial stages.

Complete production lines are designed for industrial-scale applications, with processing capacities ranging from 1 to 50 tons per day. Based on operational modes, these systems are further categorized into batch, semi-continuous, and fully continuous types. Batch systems operate on a single-reactor, batch-by-batch basis; they offer high feedstock tolerance, making them suitable for processing mixed waste with complex compositions. Semi-continuous systems utilize screw conveyor mechanisms to achieve partial automation, resulting in higher production efficiency compared to batch systems. Fully continuous systems employ a two-stage reactor configuration with screw scrapers, enabling 24-hour uninterrupted operation with a single startup cycle lasting up to 40–50 days.

Core System Components

A complete pyrolysis oil refining system comprises multiple functional units working in concert.

The distillation and separation system constitutes the core of the refining process. Packed distillation columns are widely used in pyrolysis oil rectification due to their high separation efficiency, low pressure drop, and operational flexibility. Meanwhile, thin-film evaporators utilize jacketed heating to separate solvents from pyrolysis oil at temperatures below the oil's boiling point, making them well-suited for continuous operation scenarios. Distillation columns are typically equipped with 10 to 30 trays, with the reflux ratio maintained between 2:1 and 10:1.

The heating and temperature control systems provide a stable heat source for the distillation process. Reboiler temperatures are generally controlled within the 190°C to 270°C range to ensure the effective recovery of light components, such as benzene-series compounds. The temperature control precision of the heat exchangers directly impacts separation efficiency and product quality.

Condensation and vacuum systems are responsible for condensing and collecting the vaporized oil and gas components. Operating under vacuum conditions allows for lower distillation temperatures, thereby minimizing decomposition losses of heat-sensitive substances. The matching design of condensers and vacuum pumps must be optimized based on processing capacity and the boiling points of the target fractions.

Adsorption and refining systems are employed to remove pigments, odors, and polar compounds from the oil. Adsorbents such as activated attapulgite effectively capture impurities in the pyrolysis oil, improving both product appearance and stability.

Environmental protection and safety configurations include spray-based dust removal, activated carbon adsorption, UV-photocatalytic deodorization, and desulfurization towers. Sealed feeding and nitrogen purging systems ensure operational safety and minimize the escape of harmful gases.

Technological Trends

Current pyrolysis oil refining equipment is evolving toward continuous, automated, and clean operations. PLC control systems enable fully automated process management, requiring only one or two operators per production line. In terms of process technology, the combined application of membrane distillation systems and catalytic cracking techniques has further enhanced the yield and quality of diesel fractions.

From an engineering perspective, equipment selection requires a comprehensive assessment of factors such as feedstock characteristics, target product specifications, investment budgets, and environmental regulations. Skid-mounted units are suitable for process validation and small-scale production, whereas continuous production lines are better suited for industrial projects aiming for economies of scale. As the rectification technology for waste tire pyrolysis oil advances from laboratory scale to industrial demonstration scale, the standardization and modularity of the equipment will continue to improve.