Foam Generation in Rotor-Stator Mixers

non-ideality, it will tend to reduce differences between calibraiion and predictior;. To do this of course is not always possible, particularly where the effect of changing dyebath conditions is under consideration, e.g. liquor ratio, electrolyte concentration, pH and dye concentration. To attempt calibration experiments to adequately cover the results of such changes would remove the need for prediction. If one of the changes in conditions anticipated is that of ternperature then obviously the calibration experiments would have to include a measure of the heats of dyeing of the dyes concerned, so that the affinities used would be correct or correctable to the temperatures involved. It may be considered that the treatment developed presents something of an 'over-kill', particularly in terms of the determination of the amounts of all the different ionic species in the system originating from a variety of sources. For many dyeing systems this is indeed true, i.e. in dyebaths of high liquor ratio and in the presence of moderate to high concentrations of added electrolyte, where the adventitious contribution of ions from other sources could be negligible. On the other hand there are other cases where such considerations would be warranted, e.g. when dyeing a fibre such as wool, which has a considerable potentiality t o contribute ions, at low liquor ratios with the minimum addition of electrolyte. Since the application of the treatment clearly calls for the use of a computer there should be no problems in covering all eventualities, apart from the increased complexity of the computer program. However, once written, the program can be used in the general sense if so desired or in a suitably modified way by using the appropriate data input. The equations produced are complex and if the only method of evaluation available was by manual calculation then the time required would be a serious obstacle to their usefulness in practical circumstances. However, the continuing development of computers has totally removed this difficulty, so much so that the practical use of these methods could well be an online procedure once the necessary computer programs are available.