A chelating agent system for the removal of barium sulfate scale

Zhifeng Luo,Lin Wu,Chunlei Wang,Hongyu Ji,Nanlin Zhang,Pingli Liu,Liqiang Zhao

doi:10.1007/s13202-020-00886-5

Abstract

This study aimed to prepare a chelating agent SA-20 using diethylenetriaminepentaacetic acid (DTPA) and low molecular weight sodium polyacrylate raw material for the removal of barium sulfate (BaSO4) scale. The morphology of the resulting chelating agent was characterized by scanning electron microscopy. The BaSO4 scale removal ability of SA-20 was comprehensively evaluated by the dissolving ability, particle size analysis, corrosion performance, and fracture conductivity before and after the scale removal. The results showed that the SA-20 has a good BaSO4 scale removal ability due to the chelation, lattice distortion, and dispersion of DTPA and low molecular weight sodium polyacrylate.

Highlights

With the development of the global oil and gas industry, higher requirements are put forward for drilling and stimulation (Luo et al 2019)
Barite, whose main constituent was barium sulfate (BaSO4), was usually added into a drilling fluid as a weighting material to increase the fluid density of a drilling fluid (Elshreef and Lashin 2016; Fang et al 2018; Nguyen et al 2011; Srungavarapu et al 2018)
The micromorphology of the product formed by the chelating agent system SA-20 and Ba2+ was characterized by SEM

Summary

Introduction

With the development of the global oil and gas industry, higher requirements are put forward for drilling and stimulation (Luo et al 2019). Barite, whose main constituent was barium sulfate (BaSO4), was usually added into a drilling fluid as a weighting material to increase the fluid density of a drilling fluid (Elshreef and Lashin 2016; Fang et al 2018; Nguyen et al 2011; Srungavarapu et al 2018). Most drilling fluid was lost and entered the reservoir, and solid particles, such as BaSO4, were deposited in the reservoir, resulting in the damage of the reservoir (Al-Yami et al 2010; Bozau et al 2015; Liu et al 2017; Mozaffari et al 2015, 2017b; Shahbazi et al 2006). It is important to develop a chelating system for the removal of the BaSO4 scale. The development of the chelating agent mainly focused on a slightly soluble sulfate scale–dissolving agent (Egermann et al 2002).

Objectives

Methods

Results