Study On Key Device Of Supercritical Fluid Spray Dyeing And Wrap Dyeing Process

The status and characteristics of process, conditions and device of supercritical fluid dyeing (SFD) and supercritical fluid wrap dyeing technology are summarized and analyzed in this paper, and the problems of the traditional SFD process are pointed out. The principle of supercritical fluid spray dyeing technology is introduced, and it overcomes the shortcomings of current SFD, has the advantages of simple process, low equipment requirement, energy saving and environmental protection with broad prospect of application and research.On the basis the improvement of the current supercritical fluid wrap dyeing process and device of our group, an integral set of process on supercritical fluid spray dyeing is devised and the specific operation process is given.In order to solve the problem brought out in the process of current supercritical fluid wrap dyeing such as heat transfer, conveyer and drive device, we have done some innovative design, including a novel plate exchanger of multi-medium streams under high pressure, which is specially used for supercritical carbon dioxide generation unit, a circulation pump that can meet the demand of high temperature and high pressure processing condition and a shield electric machine for the drive of textile in dyeing unit. Specific structure and design idea are given, as well as the process and strength calculation.As for the spray process of single orifice, author put up the simulation and optimization of its flow field by supposing the fluid is the pure supercritical fluid, the internal surface of orifice is smooth and the flow status of the fluid is steady. Based on the establishment of the physical and geometrical model of the single orifice is, author use the real gas model based on the R-K equation to simulate. According to the single factor simulation experiment, several group simulation experiments are carried out. Based on the analysis of the simulation result, structure parameters of orifice are optimized.On the basis of the above optimization, we simplify the textile as a very thin layer of porous medium to simulate the flow field of spray dyeing process under the result of the optimization of nozzle structure.We establish the model of multi-orifice integrated nozzle, and simulate the flow field of spray dyeing process with multi-orifice and investigated the effects of interference between the adjacent orifices. According to the simulation result, the structure of the multi-orifice integrated nozzle is improved, and the parameter of orifice is optimized. And it shows that the improved nozzle structure can make the flow field distribution of the spray dyeing process more uniform than before.