The pump described in this paper is based on an unusual working principle which makes it suitable for handling difficult-to-pump dangerous liquids. It is driven by a two-phase alternating air flow and in its fluidic rectifier part that comes into contact with the liquid has no moving or deformed components. It is thus leak-proof, extremely reliable, and needs no maintenance. The rectifier may be described as a series-connected array of jet-pump units with annular Coanda-effect nozzles. Each odd one of the units is connected to one phase of the driving air flow - and each even unit to the other phase. The air acts periodically on the liquid in vertical displacement tubes on top of each unit. The outflow from these tubes generates in all even jet-pump units an annular synthetic jet, attaching by the Coanda effect to curved wall that diverts it downstream, towards the pump output. At the same time in the odd jet-pump units the orientation of the nozzles makes it easy for the liquid to enter into them from upstream. An important additional pumping effect is generated by travelling waves passing through the whole array. The pump rectifier is robust and may be made of materials withstanding high temperature, chemical aggressiveness of the liquid, or special conditions like exposure to radioactivity. (C) 2010 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.