Patent ID: 8435936

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 wherein the aqueous detergent slurry comprises from 25 wt % to 35 wt % water; (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 detergent ingredient 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 the drop in pressure between (i) the pressure in the pipe at the outlet of the first pump to (ii) the pressure in the pipe at the inlet to the second pump is less than about 8×10 5 Pa.