Shihui Gao

Bio‐degumming optimization parameters of kenaf based on a neural network model

In order to decrease kenaf chemical residues and environmental pollution caused by conventional degumming methods, the present work used a biological enzyme degumming technique to degum kenaf, where the enzyme was the secretion from Aspergillus niger‐kenaf. A neural network model was established based on the experimental results, and the optimal processing parameters of degumming were determined finally with genetic algorithm through a fuzzy relationship between the processing parameters and degumming effects. The optimized parameters are: 34.11°C, pH value 8, bath ratio 1:37.61, time 60 h, and enzyme consumption 1.00 ml/10 g kenaf fiber. The residual gum content and weight‐loss ratio obtained from experimental results were consistent with those given by the model, and the average errors between them were 2.15% and 4.3%, respectively. This work shows that optimized degumming processes could be achieved using this model by avoiding time‐consuming and costly trial‐and‐error tests.

Automatic Control of Supercritical CO2 Fluid Dyeing

The home-made equipment and its working principle were introduced. Dyeing by this equipment makes the color fastness to rubbing, sunning and washing of modified cotton fabrics to reach level 4-5, as well as a good dyeing evenness. Design the automatic control system of Supercritical CO2 Fluid dyeing equipment, and research on practical applications of fuzzy controller is investigated. On analysis of the features of technique, in order to reach a good dyeing effect, controlling the temperature and pressure of dyeing equipment is the key technology development of control system. Those variables have the characters of non-linearity, time-variation, and inter-coordination, etc. Fuzzy control strategy can enhance the capacity of resisting disturbance of system in different states and external conditions, which can reach an excellent control effect. Therefore, the research utilizes fuzzy controller to control the equipment, which makes its process parameter realize the real-time monitor and accuracy control under the condition of close to the optimal condition. Also, human-machine interaction interface increases the programming quality, and makes the functions of monitor and control reasonably arranged.

Visualization Technology of Supercritical Fluid Dyeing

A visualization technology of supercritical CO2 dyeing and automatic control system was proposed, and 3D MAX software was developed to simulate kettle structure diagram for visualization in supercritical CO2 dyeing device. Meanwhile, the internal structure and function of the reactor were researched and supercritical CO2 fluid flow and the change process of the dye in the dyeing kettle and dye make-up kettle were analyzed. The staining mechanism of high temperature and pressure in the reactor was identified to provide a reference for visualization techniques of the supercritical CO2 dyeing.