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I. Preparation Work 1. Container Inspection Check the integrity of the container, including whether the container body, inlet and outlet pipes, valves, and other components are firmly connected without any leakage points. Ensure that there are no debris or standing water inside the container. 2. For equipment preparation, select an appropriate purge gas source, such as nitrogen or compressed air. If nitrogen is used, ensure an adequate supply of it and that its purity meets the requirements (typically, industrial nitrogen has a purity of over 99.9%). Connect the purge gas source to the inlet of the container, and install a suitable discharge device at the outlet of the container, such as a temporary pipe leading to a safe discharge area. Prepare the measuring instruments, such as a dew point meter (used to measure the moisture content in gases) and pressure gauges. II. Drying and purging operations 1. Initial purging: Open the inlet valve of the container and slowly introduce the purge gas, allowing it to flow inside the container and exit through the outlet. At the beginning, the purging speed should not be too high, to prevent impurities inside the container from being lifted by the fast airflow and causing blockages or damage to the equipment. Continue purging for a period of time, such as 15–30 minutes, to initially remove loose impurities and most of the air from the container (if nitrogen is used for purging). 2. Heating during purging (if necessary): For containers that require a high level of dryness, heating can be carried out during the purging process. The container is heated using external heating devices such as steam tracing or electric heating strips, typically raising the temperature inside the container to 40 – 80°C. Purging is continued during the heating process; as the temperature rises, the evaporation rate of moisture increases, which is more conducive to drying. 3. For dryness detection, a dew point meter is used to measure the dew point of the gas discharged from the container’s outlet. The lower the dew point, the less moisture is present in the gas. When the dew point reaches a specified value (such as below -40°C, depending on the process requirements), it can be considered that the container meets the drying requirements. During the purging process, it is necessary to regularly check the pressure inside the container to ensure that it remains within safe limits, generally not exceeding the container’s design pressure. III. Post-purging treatment 1. Close the valves: Once the container has been dried and purged to the required standard, first close the inlet valve, then slowly close the outlet valve, so as to maintain a certain positive pressure inside the container (usually 0.05 – 0.1 MPa), preventing external air from entering the container and causing it to become damp again. 2. Disconnect the connections: remove the piping that connects the purge gas source to the container, as well as the temporary discharge piping at the outlet. 3. Record and label the process of drying and purging, including information such as purging time, type of gas source, and results of dryness testing. Label the container to indicate that drying and purging have been completed, along with the relevant parameters.