Bottom-blowing mixing process was studied by fabricating the hydraulics model. Experimental image data was obtained using fluid visualization and digital imaging technologies. A novel chaos detection technique 0?1 test was employed to investigating the effect of nozzles arrangement, including the number and angle, on chaotic characteristic of mixing process. The results showed that the gas hold-up content could be estimated approximately by means of color indicator and digital image processing technology. The evolution of gas hold-up has good agreement with the real experiment running state. In addition, the time series of gas hold-up were tested by 0?1 method, respectively. It was demonstrated that the values of asymptotic growth rate Kc median have basically reflected the intensity of chaotic characteristics of different experimental conditions to some extent.