Upcycling Steelmaking Slag as a Sustainable Deep-Well Drilling Weighting Agent: Performance, Mechanisms, and Environmental Impacts

This research explores the innovative use of Heavy Agent Steel Production By-product (HASPB) as a distinct steelmaking by-product applied as a densifying and bridging material in water-based drilling fluids for deep and high-pressure high-temperature (HPHT) well applications. HASPB offers a sustainable and efficient alternative to traditional weighting materials like barite and hematite. Comprehensive characterization of HASPB, including particle size distribution (PSD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM), confirmed its suitability for use in drilling fluids. Six fluid systems were formulated using barite, hematite, and HASPB at two dosages (85 g and 190 g) to systematically compare their density, rheological behavior, viscoelastic performance, and HPHT filtration properties. The results demonstrate that HASPB-based fluids achieved comparable density with the same concentration to the barite and hematite. Additionally, it enhanced yield point and showed lower plastic viscosity. In term of filtration and filter cake thickness, it showed the lowest fluid loss and filter cake permeability relative to conventional systems. These findings position HASPB as a technically viable and environmentally responsible weighting material for modern drilling fluid design.