In a continuous scouring operation, a desized fabric (with 40% wet expression) is dipped into a saturator (alkali bath) before it enters a J-box for scouring. After saturation in the alkali bath, the wet expression increases to 100%. The required alkali concentration (w/v) of the liquor present in the fabric exiting the saturator is 6%. Considering no liquor interchange in the saturator, the alkali concentration (w/v) in percentage in the saturator (in integer) is _______.