Patent ID: 8901065

Claim:
A process for preparing a spray-dried detergent powder comprising: (i) detersive surfactant; and (ii) other detergent ingredients; wherein the process comprises the steps of: (a) forming an aqueous detergent slurry in a mixer; (b) transferring the aqueous detergent slurry from the mixer to a pipe leading through a first pump and then through a second pump to a spray nozzle; (c) contacting a liquid detergent ingredient having a viscosity of less than about 2 Pa·s to the aqueous detergent slurry in the pipe after the first pump and before the second pump to form a mixture; (d) spraying the mixture through the spray nozzle into a spray-drying tower; and (e) spray-drying the mixture to form a spray-dried powder, wherein a nitrogen-rich gas is introduced between the first and second pumps; wherein the nitrogen-rich gas is pumped into the liquid detergent ingredient at a pressure of between about 0.1 MPa and about 2 MPa; and wherein no nitrogen-rich gas is injected after the second pump and prior to the spray nozzle.