On-Line Monitoring System for Hydrogenation Equipment in Petrochemical Plants

A life monitoring and assessment system of pressure vessels and piping in petrochemical plants has been developed based on the structural integrity theory and web technology. Two industrial cases of the monitoring system are given in this paper for hydrogen processing reactor, hydrogen pipeline and furnace tube of hydrogen reformer. The monitoring system is established to predict hydrogen embrittlement for the wall materials of hydrogenation reactor and pipeline in petrochemical plants. A critical description of hydrogen induced cracking is introduced to set up a criterion for the embrittlement. The electrochemistry hydrogen sensor is designed for its feasibility of real-time monitoring and assessment of hydrogen embrittlement for the equipment. It is pursued by the research to make a more impersonal judgment of safety of the hydrogenation reactor with real time tracing of operation. A remote inspection system is created based on computer network technology to monitor the plant subjected to hydrogen attack. The on-line system is also founded to monitor the operation of the furnace tube of hydrogen reformer and predict its residual life. The system executes in the remote server to assess the life of the tube and issue the information through the internet. Therefore remote users can monitor and manage the tubes on real-time. A non-contacting temperature monitoring technique is introduced into the system using CCD camera. An assessment method is introduced in this paper to create a correspondent relationship between remaining life and damage accumulation. It is significant for the method to describe the tube damage or materials degradation under unstable operations including varied pressure, varied temperature, over-heat or thermal fatigue, etc. A life fraction model related to damage accumulation is adapted into a real time monitoring system to calculate the residual life for a selected tube and work out an optimum preventive maintenance project.