Air separation technology

In the commissioning process of argon production system of new air separation plant, due to unstable gas demand and other reasons, the working condition of argon production system is easy to be fluctuated. The following is the analysis and treatment of common faults. 1. The nitrogen content in argon fraction increased Due to the small extraction amount of nitrogen products and crude nitrogen products, part of nitrogen enters into the argon production system along with argon fraction, resulting in the increase of nitrogen content in argon fraction. As a result, the temperature difference between oxygen enriched liquid air and crude argon in crude argon condenser is reduced, and normal heat exchange cannot be conducted. Finally, the crude argon cannot be condensed and the oxygen enriched liquid air cannot be evaporated. During the adjustment, the extraction amount of crude nitrogen and nitrogen is provided to reduce the outlet pressure of crude nitrogen to maintain normal operation c

The most likely leakage of switching heat exchanger is the welding line, especially the joint of the head and the pipeline. Most of the causes of leakage are the quality problems of manufacture and installation, which are also related to maintenance. The working condition of switching heat exchanger is poor. It is not only impacted by alternating airflow, but also changes greatly in airflow temperature. In long-term operation, the weak parts are easy to leak. Therefore, the welding quality should be strictly guaranteed during manufacture and installation. After installation, strict leak detection and pressure test must be carried out before driving, and problems should be dealt with timely to avoid passivity after driving. There are three methods to check whether the switching heat exchanger leaks in operation: 1) flow method. When a large amount of leakage occurs between the channel of product oxygen or product nitrogen and air channel, the output of oxygen or nitrogen increases ob...