What Are the Safety Standards for Pyrolysis Oil Refining Plants?

What Are the Safety Standards for Pyrolysis Oil Refining Plants?

The safety standards for pyrolysis oil refining plants cover four core sectors: process safety, equipment safety, personnel safety, and emergency management. These standards must comply with both national general industrial safety regulations and industry-specific requirements for solid waste pyrolysis. The details are as follows:

Process Safety Standards

Oxygen-free/Slight Negative Pressure Control: Pyrolysis reactions shall be conducted in an airtight, oxygen-free or slight negative pressure environment. Air ingress into the reactor must be strictly prohibited to prevent explosion caused by oil-gas mixture. The reaction temperature should be controlled within the range of 280–500℃. Automatic alarm and interlock shutdown systems for over-temperature (＞550℃) and over-pressure must be installed, with real-time uploading of temperature and pressure data to the monitoring platform.

Safe Utilization of Combustible Gas: The combustible gas generated during pyrolysis must be purified through desulfurization and dehydration before being recycled to the furnace for combustion support. The gas transmission pipeline shall be equipped with flame arresters and leakage detectors, which are interlocked with the furnace combustion system. In case of leakage, the gas supply must be cut off immediately and the ventilation system activated.

Raw Material Pretreatment Specifications: Raw materials such as waste tires and waste plastics shall be crushed to the specified particle size, with hard impurities like stones and metals removed to avoid damaging the reactor or causing local overheating. The proportion of chlorine-containing plastics (e.g., PVC) in feedstock must be strictly controlled or completely prohibited, to prevent the generation of toxic hydrogen chloride gas.

Equipment Safety Standards

Reactor Qualification Requirements: Pyrolysis reactors are classified as pressure vessels, which must comply with the Safety Technical Supervision Regulations for Pressure Vessels. They shall have pressure resistance, high temperature resistance and corrosion resistance performance. Third-party inspection reports must be provided before factory delivery. After commissioning, non-destructive testing (e.g., ultrasonic testing) and pressure tests shall be carried out regularly, with the inspection cycle not exceeding 3 years.

Environmental Protection and Auxiliary Equipment Standards: The condensation system must ensure high oil-gas condensation efficiency to prevent direct emission of uncondensed gas. The tail gas treatment system shall meet the Integrated Emission Standard of Air Pollutants, equipped with baghouse dust collectors, activated carbon adsorption devices and desulfurization units. The storage tank area must be installed with cofferdams and anti-seepage layers. Fuel oil and condensed water storage tanks shall be fitted with level gauges and anti-overflow devices.

Electrical Safety Standards: Electrical equipment in the plant area shall be explosion-proof type (with explosion-proof grade not lower than Ex d ⅡB T4), complying with the Code for Design of Electrical Installations in Explosive Atmospheres. The grounding resistance of the workshop shall be ≤4Ω to avoid static accumulation and subsequent explosion.

Personnel Safety Standards

Qualification and Training: Operators must receive professional safety training, pass the assessment and hold special equipment operation certificates (for pressure vessel operation). Regular HSE (Health, Safety, Environment) training shall be organized to ensure they master emergency response skills for high-temperature scalds, gas leakage, fire and other accidents.

Personal Protective Requirements: Workers shall wear high-temperature heat-insulating suits, gas masks against toxic gases, goggles and anti-smash safety shoes. When conducting maintenance inside the reactor, the Lockout/Tagout (LOTO) system must be implemented. Gas detection (oxygen content, toxic and harmful gas concentration) shall be performed, and monitoring personnel must be assigned on site.

Emergency Management Standards

Emergency Plans and Drills: Special emergency plans for fire, explosion and toxic gas leakage shall be formulated, defining the emergency organization structure, response procedures and material reserves. Emergency drills shall be conducted at least twice a year, with drill results documented and used to optimize the emergency plans.

Emergency Material Configuration: The plant area shall be equipped with dry powder fire extinguishers, carbon dioxide fire extinguishers, fire sand and fire water systems. Emergency eyewash stations and emergency shower facilities shall be installed at key locations such as reactors and storage tank areas. Emergency supplies including gas masks and first-aid kits shall be stocked and inspected for replacement regularly.

Accident Reporting Specifications: In the event of a safety or environmental accident, the emergency plan must be activated immediately, and the accident must be reported to the local emergency management and ecological environment departments in accordance with regulations. Concealment or false reporting of accidents is strictly prohibited.

In addition, there are specific standards in different countries and regions. For example, plants in the EU must comply with CE certification and the SEVESO Directive (major accident risk prevention and control), while plants in the U.S. must follow OSHA (Occupational Safety and Health Standards) and EPA (Environmental Protection Emission Standards).