Scale deposition in producing wellbores is a serious problem in the industry. The problem gets worse, when the scale is caused due to barium and strontium salts. These salts are difficult to clean as they are not easily soluble in any kinds of solution or chelating agents. In case of offshore operation, the scaling phenomenon is inevitable, as sea water injection is done.

Formation of scales changes the surface roughness of the production tubing, thereby increasing the frictional pressure drop leading to a decreased production rate. Further deposition clogs the production tubing, creating hindrances for lowering tools into lower sections of the production string. In worst cases tubing replacement needs to be done, which is a capital intensive activity.

Creating a super hydrophobic surface with multi-scale nano structures on the inside of the production tubing can greatly reduce the chances of scale deposition. This surface is created on epoxy paint surfaces using a feasible dip coating process. Microstructures are created on this surface using sandblast. Then nano structures are introduced on to the micro surface by anchoring 50–100 micro-meter SiO2 particles and finally completed by dip coating with nano SiO2/epoxy adhesive solution. The hydrophobicity is further enhanced by another dip coating of a low surface energy polymer, aminopropyl. The super hydrophobic surface shows a contact angle of 167.8 degrees (Cui, Yin, Wang et al. 2009) for water, and has high stability in basic and common organic solvents.

The ions are carried in the water present in the crude. By increasing the contact angle for water, the chances of deposition of the ions that pose scaling can be reduced. This method may provide a long term solution for scale deposition especially in offshore fields where scaling incurs huge losses.

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