Hilbert-Huang transformation has been applied to extract eigenvectors from the pressure fluctuation signals in the spouted bed. According on these eigenvectors, the flow regimes in the spouted bed could be classified into 4 clusters including 'packed bed', 'stable spouting', 'bubbling fluidized bed' and 'slugging bed' by chaos optimized fuzzy c-means clustering algorithm. The Elman neural network was used to recognize these four flow regimes, and the parameters in the Elman neural network were optimized by adaptive fuzzy particle swarm optimization algorithm. The recognition accuracies of 'packed bed', 'stable spouting', 'bubbling fluidized bed' and 'slugging bed' can reach 85%, 90%, 85% and 80% respectively. (C) 2010 Elsevier B.V. All rights reserved.