Introducing a Method for Backflow Detection in Lobe Blowers through Ultrasonic Technique

In sponge iron production plants utilizing the direct reduction method, it is very common to use lobe blowers to transfer process gas. The volumetric efficiency of lobe blowers depends on the clearance between their fixed and moving parts. An increase in this clearance can result in backflow, which means that the flow returns from the high-pressure outlet zone to the low-pressure inlet zone. This research aims to assess the feasibility of using ultrasonic techniques to detect backflow. The sample of this research includes four blowers manufactured by AERZEN company, located in the first and third modules of Khuzestan Steel Company. Data analysis results show that the ultrasonic technique can detect the presence of backflow. Furthermore, verification of the results is conducted through an experiment that includes blocking the blowers’ outlets and measuring the ampere consumption and the output pressure. The findings of verification confirm the results obtained via ultrasonic technique. Furthermore, this research proposes the crest factor ratio feature as a metric for detecting backflow.