Feeding liquids to mixer free from occluded air - by recirculating from mixer to just beneath level in tank

摘要

Homogeneous or foamed materials are produced from at least two liq. reagents fed to a mixer and released after mixing, at least one reagent being recirculated into its supply tank just below the level of liquid there but at a significant distance from the outlet. Polyol is stored in a tank (1) whose outlet (5) is in the base (4) from which it flows via a dosing pump (7) to the mixing head (8). Another pipe leads back from the mixer (8) to the tank (1). A flexible tube (12) is of length equal to the max. depth in the tank (1) and its top end (13) is fixed to a float(14). This float (14) moves on a vertical guide (15). The recirculated polyol reagent thus returns to its tank without contact with air and at max. distance from the outlet (5). System prevents occlusion of air into reagents.