A New Ultrasonic Reactor for CaCO3 Antiscaling in Pipelines and Equipment

Abstract

Summary Calcium carbonate (CaCO3) scaling is one of the main drawbacks in oil and gas production pipelines and equipment, contributing to the reduction or shutdown of production in petroleum extraction industries. This work shows a new device for the prevention of calcium carbonate scale in oil and gas production units. Three cells containing five ultrasonic transducers each (60 W×40 kHz) were used to reduce carbonate scaling in pipelines. Long-term tests were carried out in a semi-industrial hydraulic system that was properly instrumented to allow us to simulate CaCO3 production by injection of CaCl2·2H2O and NaHCO3. A proof valve was positioned downstream of the equipment. Pressure drop in the valve, scale mass on the pipe samples, and morphology of crystals were evaluated after 2 hours of testing. Well-marked reductions in pressure drop (up to 96%) on the proof-valve and scale thickness (up to 95%) in pipe samples were verified when compared with the system without any scale prevention device. Scanning electron microscopy (SEM) images showed alteration of the geometry and reduction of the particle size as the main reason for the reduction of scaling.