Crystallization of Barium Sulfate (BaSO₄) in a Flowing System: Influence of malic acid on Induction Time and Crystal Phase Transformation

¹ Department of Mechanical Engineering, Faculty of Engineering, Diponegoro University, Tembalang Campus, Semarang 50275, Indonesia
² Department of Chemical Engineering, UNTAG University in Semarang

^* Corresponding author: wap_mesin@yahoo.co.id

Abstract

Barium sulfate scaling usually occurs in pipelines of offshore oil drilling wells, which has become a persistent problem. This scale can create technical problems, including the increased energy in consumption and unscheduled equipment shutdown. This paper presents the crystallization of barium sulfate and this experiment was focused on evaluating the effect of solution concentration and malic acid to the induction time and barium sulfate crystallization. In this research, the experiments on the growth of barium sulfate scale in the pipe test was conducted by reacting BaCl₂ and Na₂SO₄ at concentrations of 3500, 4000, 4500 and 5000 ppm Ba2+, flow rate (40 ml / min), temperature (50 °C), while malic acid (0, 5, 10 ppm) was added to the solution as a scale inhibitor. BaSO₄ scale formation was observed with the declining value of the conductivity of the solution. BaSO₄ crystal shape was observed from the results of morphological studies performed using SEM, further analysis of the micro-crystal composition using EDX and XRD analysis was used to prove the crystal produced. The SEM imaging shows that the morphology crystals have a star-like particle, while XRD analysis confirmed that the pure barite crystal (barite) was produced during the experiments. Obviously, the malic acid inhibited the crystal growth of barite.