What are the best ways to prevent sand production in your well?

1 Sand control objectives

The main objectives of sand control are to stabilize the formation, retain the sand in place, and ensure the flow of fluids without excessive pressure drop or erosion. To achieve these objectives, you need to consider several factors, such as the sand size distribution, the formation strength, the stress regime, the fluid properties, the flow rate, and the well geometry. Depending on these factors, you can choose among different sand control techniques, such as mechanical, chemical, or hydraulic methods.

2 Mechanical methods

Mechanical methods involve the use of physical barriers or devices to prevent or limit the movement of sand particles into the wellbore. Gravel packing is one of the most widely used and effective sand control methods, especially for high-rate and long-term wells. This involves placing a layer of gravel or sand between the formation and the perforated casing or screen, acting as a filter that prevents formation sand from entering the wellbore. Screens are also used, which have openings or slots that are smaller than the formation sand size, thus blocking it from entering. These can be wire-wrapped, pre-packed, slotted liner, or expandable screens. Frac and pack is another method, combining hydraulic fracturing and gravel packing; this is often used for low-permeability or tight formations. All of these mechanical methods can provide effective sand control, but they differ in cost and complexity.

3 Chemical methods

Chemical methods involve using chemical agents or additives to modify the properties of the formation or fluids, in order to reduce or prevent sand production. Consolidation is a common method used, where a resin or polymer is injected into the formation, binding the sand grains together and forming a solid matrix. This increases the strength and stability of the formation and prevents sand from flowing into the wellbore. Inhibition is another method used, which involves injecting a chemical inhibitor into the formation, reducing the tendency of the sand grains to move or migrate under stress or flow conditions. Inhibition can act by coating the sand grains, altering their surface charge, or creating a gel-like structure. Both consolidation and inhibition are usually applied when mechanical methods may not be feasible or reliable.

4 Hydraulic methods

Hydraulic methods involve the use of fluid flow or pressure to control or prevent sand production. Rate control, for example, involves adjusting the flow rate or drawdown of the well to avoid exceeding the critical rate or pressure that can cause sand production - which depends on the formation characteristics, such as the sand size, the porosity, the permeability, and the stress state. This method is usually applied as a preventive or remedial measure when other methods are not available or effective. Additionally, water injection can be used to maintain or increase reservoir pressure and reduce the effective stress on the formation, preventing or delaying sand production. This method is usually applied as a secondary or tertiary recovery method to enhance oil recovery and extend well life. These are some of the best ways to prevent sand production in your well, depending on your specific reservoir and well conditions. By applying the appropriate sand control methods, you can improve the performance and safety of your well, while optimizing your production and recovery.

5 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?