First, drain the remaining fuel from the tank to ensure no residual liquid remains. Then, inspect the interior of the tank for rust, impurities, or sediment, and identify the cleaning priorities. Prepare appropriate cleaning tools and cleaning agents, ensuring they are compatible with the fuel type to avoid chemical reactions. Operators must wear protective equipment, such as gloves and goggles, for their own safety.

Depending on the degree of contamination and internal conditions of the tank, manual or mechanical cleaning can be used. Manual cleaning is suitable for tanks with minimal impurities and simple structures, requiring manual wiping and cleaning with tools. Mechanical cleaning utilizes specialized equipment, such as a high-pressure washer, to flush the interior of the tank with high-pressure water, improving cleaning efficiency and particularly suitable for heavily contaminated areas.

First, rinse the inside of the tank with clean water to remove surface dust and loose debris. Then, evenly spray or apply the prepared cleaning agent to the inside of the tank. Let it sit for a while to allow the agent to fully work and dissolve oil and stubborn deposits. Rinse repeatedly with clean water until the rinse solution is clear and no residual cleaning agent remains. Particularly clean corners and valve connections, areas prone to accumulation of debris, to avoid missing any areas.

Carefully inspect the inside of the tank for cleanliness and residual dirt, debris, or traces of cleaning agent. Inspect the surface of the tank for damage, such as scratches or corrosion. Address any issues promptly. Also, check the seals of all connections and valves to ensure that cleaning does not affect the tank's normal operation and prevent leaks.

Keep the cleaning area away from sources of fire, heat, and open flames. Smoking and using equipment that could produce sparks are prohibited nearby to prevent safety hazards. Maintain good ventilation during the cleaning process to prevent the accumulation of gases generated by the volatilization of cleaning agents. After cleaning, properly dispose of the cleaning waste liquid to avoid arbitrary discharge and environmental pollution, and dispose of it in accordance with relevant environmental protection regulations.