Sanding: A Rigorous Examination of the Interplay Between Drawdown, Depletion, Start-Up Frequency and Water Cut

Abstract

Factors and mechanisms leading to sanding are described within an integrated-rock and soil-mechanics framework. While the conventional sanding models generally consider a single mechanism for sanding, namely the critical depletion resulting in rock disaggregation, the proposed approach considers the interplay of several mechanisms that can lead to the rock breakup and sand transport. One important difference is that rock disaggregation is not seen to represent the onset of sanding, because the sand mass can offer significant resistance from frictional properties, interlocking of sand grains, and arching. The approach presented here can be used to explain why sanding in the field tends to be episodic, and how depletion, which is a major factor in rock breakup, can be highly effective in holding broken-up sand grains together and, in fact, become a sand-stabilizing agent.The proposed approach is used in discussing sanding at several wells in two different fields. These wells have been in production for several years and show that sanding cannot be linked to just one unique mechanism (e.g., depletion). However, once all mechanisms for sanding are incorporated, a more consistent analysis can be used by completion and production engineers to make more objective and pragmatic decisions in managing sanding while maximizing production over the life of the well.

Scientific and Methodological Support of Sand Management During Operation of Horizontal Wells

“…Sand production depends on the water/oil/gas distribution in the total flow of the fluid (9,10). Some researchers argue that this is solely a problem of arch stability (11), whilst others argue that this is an issue of wetting and chemical reactions (12) or strain softening due to water incorporating into the rock matrix (13).…”

Critical drawdown pressure prediction for sanding production of underground gas storage in a depleted reservoir in China

“…Willson et al 20 proposed a prediction method for sand production rate by introducing load factor (intensity‐normalized near‐well formation pressure) and Reynolds number (a function of permeability, viscosity, density and flow rate), and derived the empirical relationship among these parameters. However, only single sanding mechanism was considered in these studies, while the interaction of influencing factors such as perforation size, frequency, and direction, particle size, and shape, depth, pressure, permeability and fluid type, was neglected 21 …”

“…However, only single sanding mechanism was considered in these studies, while the interaction of influencing factors such as perforation size, frequency, and direction, particle size, and shape, depth, pressure, permeability and fluid type, was neglected. 21 Many scholars have also conducted experiments on sanding production in the lab. Tronvoll 22 conducted large scale simulation experiments on sand production in the lab and found that fluid flow had little effect on cavity failure.…”

Evaluation of the behaviour of the lateral boreholes in the Gorm chalk field

“…Moreover, test data on chalk show that with plastic deformation, the tensile strength reduces [15] . Several authors have reported the importance of the permissible well drawdown scheme for mitigating the solid production, thus the bean-up process is one of the effective means of controlling the solids production [16][17][18][19] . Beaning-up refers to the process of increasing the choke size to open up a well for production and it is a frequent event following a well shutdown.…”

“…Beaning-up refers to the process of increasing the choke size to open up a well for production and it is a frequent event following a well shutdown. For weakly cemented formations, initial stages of bean-up after the rapid shut-down may affect the extent of elastic rebound of the grains, which is impacted directly by the magnitude of drawdown [17] . If bean-up (also shut-down) rate is aggressive, as a consequence, the potential for damaging the well increases, where generated transient gradients of pressure may mobilize fines.…”