High-Frequency Sonication as an Unconventional Solution to Control Fluid Loss in Water-Based Drilling Muds

TL;DR

This study shows that using high-frequency sound waves on drilling mud can reduce fluid loss without adding chemicals, but the effect depends on the size of the pores in the formation.

Contribution

The novel use of ultrasonication on base drilling mud alone to reduce fluid loss without additives is explored.

Findings

Ultrasonication reduced filtrate loss by 16–45% in disks with pore sizes of 5–20 μm.

Sonicated mud formed thinner and less permeable filter cakes compared to unsonicated mud.

Fluid loss increased at 35 μm pore size, indicating limitations in larger pores.

Abstract

Conventional methods of mitigating fluid loss in drilling
operations
rely heavily on chemical additives and nanoparticles, which may alter
mud properties and introduce environmental and cost challenges. While
the technique of ultrasonication is widely used in the oil and gas
industry, especially for mixing these additives and nanoparticles
into mud samples, the direct impact of ultrasonication of the base
drilling mud sample alone on fluid loss behavior has been largely
overlooked. This study investigates the effectiveness of ultrasonication
in modifying the filtrate loss characteristics of water-based mud
without any fluid loss additives. Drilling mud samples were subjected
to ultrasonic treatment and compared with unsonicated samples through
a series of high-pressure high-temperature (HPHT) filtration tests
using ceramic disks with average pore throat sizes of 5–35
μm. The results demonstrate that sonicated mud significantly
reduces filtrate loss, particularly in disks with smaller pore sizes,
compared with unsonicated mud. Reductions in filtrate loss of approximately
16–45% were achieved with the 5, 10, and 20 μm pore size
disks when sonicated mud was tested. These improvements were associated
with the thinner and less permeable (0.2–0.4 mm) filter cakes
compared to those of unsonicated mud, contributing to improved fluid
retention. However, at a pore throat size of 35 μm, a significant
increase in fluid loss was observed, suggesting that the benefits
of ultrasonication are limited when the pore sizes exceed the effective
range of the modified particle size distribution in the mud. Particle
size distribution and scanning electron microscopy (SEM) data confirmed
that ultrasonication fragmented and dispersed larger particles/aggregations,
leading to a more stable suspension in the mud and denser mud cakes.
The findings from this study demonstrate that ultrasonication of the
base drilling mud alone is sufficient to improve its filtrate loss
properties in most cases without the need for loss additives while
being environmentally friendly and cost-effective. However, the study
also implies the importance of adapting mud systems to formation properties,
highlighting the critical role of the interaction between the particle
size and pore dimensions in influencing fluid loss behavior and mud
cake properties.

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