The petrochemical industry encompasses core scenarios such as oil refineries, chemical plants, oil storage depots, oil pipelines and loading/unloading areas, involving flammable and explosive media such as crude oil, refined oil products, and chemical raw materials. Various equipment are installed in open-air or semi-enclosed conditions, and the production areas have special working conditions such as high temperatures, high pressures, and flammability and explosiveness. The risk of lightning strikes is much higher than in ordinary industries. Lightning strikes can damage production equipment, control systems, and instruments through direct strikes, induction, line conduction, and ground potential rebound, causing major safety accidents such as leakage, explosion, and fire of flammable media, resulting in casualties and huge economic losses. This solution is based on industry standards such as GB 50057-2010 "Building Lightning Protection Design Code" and SH/T 3081-2019 "Petrochemical Instrument Grounding Design Code", and combines the characteristics of the petrochemical industry and lightning protection pain points to build a comprehensive and differentiated lightning protection system, taking into account safety, practicality, and compliance, providing reliable protection for the safety of petrochemical production. 

I. External Direct Lightning Protection Measures. For open-air equipment and buildings in petrochemical plants, direct lightning risks are the primary concern. For tall equipment such as oil storage tanks, reaction vessels, and tower equipment, and for building structures in the equipment area, the metal shells should be utilized as natural lightning arresters (metal thickness ≥ 4mm and corrosion control meets standards). In areas without metal shells, φ12 hot-dip galvanized round steel lightning protection strips should be laid. The protection range is calculated using the ball-throwing method to ensure complete coverage of all equipment and devices. For open facilities such as oil pipelines and loading/unloading hatches, independent lightning rods should be installed. They are made of φ14 hot-dip galvanized round steel and the installation height ensures full coverage of the protection range. Down conductors should primarily utilize the metal brackets of equipment and the steel columns of buildings as natural down conductors. For non-metallic structures, φ10 hot-dip galvanized round steel artificial down conductors should be laid. Grounding clamps should be set at a height of 0.3 - 1.8m from the ground for easy inspection and maintenance. The grounding system adopts a combined grounding method. Horizontal grounding bodies use 25×4mm hot-dip galvanized flat steel (buried depth ≥ 0.8m), and vertical grounding electrodes use 50×50×5mm hot-dip galvanized angle steel (length ≥ 2.5m), with a spacing of 5 - 8m. The grounding resistance should be ≤ 4Ω. In flammable and explosive areas, the grounding resistance should be strictly controlled ≤ 1Ω to avoid sparks caused by lightning strikes and potential hazards. 

II. Internal Induction Lightning and Line Protection Measures. Focus on the production control systems and instrument circuits of petrochemical plants, and prevent induction lightning and line transmission risks. The power system implements graded protection: the main distribution room installs level I SPD (10/350μs, Imax ≥ 60kA), the distribution box in the equipment area installs level II SPD (8/20μs, In ≥ 40kA), and the terminals of precision instruments and control systems are equipped with level III fine protection SPD to prevent surge voltage from invading the core circuits of the equipment. In terms of signal line protection, instrument signal lines and control cables use shielded cables, which are laid in metal pipes or metal troughs and grounded at both ends. The strong and weak current lines are laid separately, with a spacing of ≥ 1m. In flammable and explosive areas, shielded cables for lines are used, and special explosion-proof SPD is installed to prevent induction lightning from causing line failures. 

III. Special Equipment and Regional Lightning Protection. For core equipment in the petrochemical industry and high-risk areas, differentiated protection measures are adopted. For oil storage depots and hazardous goods storage areas: the metal shells of storage tanks are reliably grounded, explosion-proof lightning arresters are installed on the tank tops, the tanks are reliably connected to the grounding system, and explosion-proof SPDs are installed at the loading and unloading areas to prevent lightning strikes from causing leaks and explosions during loading and unloading. For production equipment such as reaction vessels and distillation towers: the equipment shells, pipelines, and flanges are all reliably grounded, dedicated explosion-proof SPDs are installed at the power input terminals, and the control systems use shielded lines to prevent lightning strikes from causing equipment shutdown and medium leakage. For the central control room and instrument machine rooms: a Faraday cage shielding structure is adopted, and all equipment and cabinets in the machine rooms are uniformly connected to the main grounding busbar. Appropriate SPDs are installed on the power and signal lines to ensure the stable operation of the control system. For oil pipelines: a grounding electrode is set every 500 meters, and copper braided belts are used for cross-connection at the pipeline interfaces to prevent lightning strikes from generating potential differences and sparks. 

IV. Operation Management and Emergency Response. Establish a strict and regular operation management mechanism to ensure the long-term effectiveness of the lightning protection system. Lightning protection facilities in flammable and explosive areas should be inspected once every quarter, while those in ordinary areas should be inspected once every six months. Special attention should be paid to checking the corrosion of lightning arresters, the reliability of the down conductors' connections, the performance of SPDs, and the grounding resistance. Old or damaged components should be replaced promptly, and any issues such as damage or poor sealing of SPDs in explosion-proof areas should be strictly avoided. A complete operation log should be established to record the installation, inspection, and maintenance details, enabling full traceability throughout the process. Develop a lightning strike emergency plan, clearly defining the procedures for personnel evacuation, equipment shutdown, and leakage disposal after a lightning strike in flammable and explosive areas. Strengthen emergency duty during thunderstorm seasons. Regularly conduct professional training for operation personnel to enhance their capabilities in lightning detection, emergency response, and explosion prevention operations. 

This plan strictly adheres to the industry standards of the petrochemical sector, specifically addressing the lightning protection challenges of its flammable and explosive nature as well as the dense distribution of equipment. It simplifies redundant construction, takes into account both the protection effect and the explosion prevention requirements, and can be directly implemented. Through comprehensive lightning protection measures, it effectively intercepts direct lightning strikes, suppresses induced lightning, and prevents ground potential surges, significantly reducing the probability of safety accidents caused by lightning strikes, and effectively ensuring the safety of petrochemical production, personnel safety, and stable operation of equipment.