Aside from heavy oil, there are many viscous fluids encountered in oil production and processing. Many of these will show up in production streams and affect Facilities Sand Management. The viscosity of each stream will affect sand removal and management.

From Wellbore…

Gel fracturing fluids

• Linear or crosslink gel polymers – guar, HPG, CMHPG, HEC, borate, etc.
• Linear gel: 10-30 cP
• Crosslinked gel: 100-1000 cP

Viscosity enhanced water

• Water frac w/ additives: 2-3 cP
• Viscoelastic surfactant based polymer free fluid: 50-200 cP

Foam

• Usually CO₂ or N₂ based
• Apparent viscosity: 5-30 cP

In Facilities…

Ethylene Glycol

• MEG injected into (subsea) pipeline/tie-backs as hydrate inhibitor
• Pure: 5-20 cP / Aqueous solutions: 1-20 cP

Emulsions

• Viscosity is all over the place
• Water-in-oil or oil-in-water: complicated and stabilized by solids
• Can go to >1000 cP very easily

Slop/Backwash Streams

• Flotation skimming
• Nut shell filter backwash
• Tend to be emulsions
• Low flow, low P & T, high viscosity

From EOR Operations…

Ex: Xanthan gum (XG) and Hydrolyzed Polyacrylamide (HPAM)

• In reservoir: 100-1000 cP, at facilities 2-10 cP

Other…

Various refined products:

• Kerosene: 1-2 cP
• Asphalt: 500-2000 cP
• Lube oil: 10-20 cP
• #2 Fuel oil: 4-8 cP
• #2 Diesel: 2-3 cP

Other:

• Methanol: 0.5-0.8 cP
• Seawater: 1.08 cP
• NaCl solutions: 0.4-1.8 cP

References:

1. Rawlins, C.H. 2019. “Enhanced Production Through Surface Facilities Sand Management.” SPE Distinguished Lecturer presentation. Link here

Next week I will discuss options for reducing oil viscosity for FSM.