An experimental and modeling study of barite deposition in one-dimensional tubes

Barium sulfate deposition on the inner surface of a tube is one of the most serious oil field problems affecting oil field water injection systems. The effects of tube length, liquid volume, deposition time, the profile of the Ba2+ concentration in the outlet and the pressure drop in the tubing were evaluated using a graphite furnace atomic absorption spectrometer (GFAAS) and pressure transducer methods. The deposition model of BaSO4 in the tube is presented using coupled mass balance and fluid flow equations. The deposition model contains two governing parameters, the kinetic coefficient and the deposition coefficient, which can be estimated from experimental data. The predictions from the simplified model for barium sulfate scale were in good agreement with experimental data and laboratory observations. In addition, it was proved that many factors are important for deposition kinetics, including the accumulated barium ion amount, the initial flow rate, the initial barium concentration and the deposition time. Scanning electron microscopy (SEM) images of the inlet and outlet of the tube reveal the deposition thickness and morphology.