Electrolyte Dosing Rates in Low Liquor Jet Dyeing Heavy Cotton Duck
Progressive exponential electrolyte dosing prevents surface strike and core un-dyed voids when reactive dyeing heavy cotton duck in low liquor ratio jet machines.
Sodium Sulfate Solubility
Salt Concentration
Maximum concentration of sodium sulfate that can dissolve in a unit volume of water at a given temperature determines its effectiveness as a dye promoter. In wet processing, sodium sulfate solubility dictates how much electrolyte can be added to the dye bath without causing recrystallization. This solubility is highly temperature-dependent.
Dyehouse Management
Machine operators monitor this limit to prevent solid salt crystals from depositing on the dyed fabric or clogging the pump. When sodium sulfate solubility limits are exceeded, the undissolved salt creates spotty dyeings and rough fabric patches. It is a critical check in reactive dyeing recipes.
Dissolution Mechanism
Sodium sulfate is used to force reactive dye molecules out of the liquid bath and onto the cellulosic fibre. The solubility of this salt rises sharply as the water temperature increases from ten degrees to thirty-two degrees Celsius. To prepare a concentrated stock solution, the salt is mixed in heated tanks before being dosed into the machine.
If the solution cools down below twenty degrees during transfer, crystallization occurs, which can damage the dosing valves. Maintaining the stock tank above thirty-five degrees prevents this problem and ensures a fully dissolved, uniform electrolyte concentration.
Chemical Safety
Process reliability is enhanced by keeping the dosing concentration well below the saturation point at the lowest operating temperature. It avoids expensive downtime and fabric stripping caused by salt precipitation. Proper dilution of the salt is standard in automated dye kitchens.
Optimizing Dyeing Vessel Liquor Ratios for Fabric Quality
Optimizing liquor ratios requires balancing steam and salt savings against pump turnover rates to prevent severe shade unlevelness and mechanical creasing.