The data of chemical processes often contains dynamic timing characteristics, and traditional fault detection has low usage of dynamic information, which limits the fault diagnosis performance. To address this problem,a new method of chemical process fault diagnosis based on an attention?enhanced encoder?decoder network model (AEN) was proposed. The coding part uses the LSTM to extract the feature information of the process data and combine it with the attention mechanism to utilize the dynamic information among the process data more effectively； the decoding part uses the LSTM and combines the context vector provided by the attention mechanism to provide more accurate state information for the softmax regression, and finally, the softmax regression is used to obtain the probability value of the fault category for each sample data. The introduction of the attention mechanism improves the efficiency of the model in using process dynamic information in the time domain. The proposed method is experimented with using Tennessee Eastman process data and compared with the results of standard PCA?SVM, DBN and ResNet, and the results show that the proposed method is more effective in diagnosing faults.

The failure mechanism of pipeline cracking area of ground flare burner was studied. Through the combination of low?power macro analysis, material analysis, microscopic metallographic analysis, scanning electron microscope (SEM) micro morphology and energy spectrum analysis (EDS) and experiment, the causes of pipeline failure and cracking were found out. The sensitive environment (medium), the influence of sensitive materials and stress conditions on pipeline cracking failure were further analyzed. The results show that at a certain temperature, an acidic corrosion environment of H₂S+CO₂+H₂O is formed in the pipeline, and the stainless steel material of the flare burner pipeline is seriously sensitized and has serious intergranular corrosion; Intergranular corrosion causes grain spalling on the surface of pipe wall, resulting in pitting pits, which become the crack source of stress corrosion cracks; The flare burner pipeline will produce a certain degree of stress concentration in the process of manufacturing, processing and device operation. Under the condition of corrosive medium, sensitive material and stress concentration, the flare burner pipeline will fail due to intergranular stress corrosion cracking.