Tubing pickling

Crude oil displacement/organic deposit removal 10-75gfo tt 

All possible steps (i.e., maximum-step acid treatment design) are discussed in the following sections. 

Crude oil displacement/organjc deposit removal (optional) 

This stage is applicable in oil wells in which the crude may not be compatible with acid mixtures used or in which organic deposition is believed to be present. It is also applicable where additives to ensure oil/ acid compatibility cannot be determined with confidence. Sometimes this stage may also be beneficial in gas/condensate producers. However, one should generally avoid pumping a hydrocarbon solvent into a gas-bearing formation. 

If condensate is appreciable or if it is known to accumulate near the wellbore, then a solvent stage is acceptable. An aromatic solvent, such as xylene, is used. Typically, 10-75 gallons per foot (gal/ft) are adequate, but a preferable volume is 25-50 gal/ft. Alternatively, another aromatic solvent, or a terpene solvent maybe combined with acid and surfactants. It is preferable to keep them separate, if possible. The purpose is either to displace oil away from the acid stages, to prevent sludge or emulsion, or to remove paraffin/ asphaltene wellbore deposits. 

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A. Self-supporting Tube Pickling Tank (Figure 1)... 

B. Insert for Existing Carbon Steel Tube Pickling Tank... 

Figure I. Self-supporting-tube pickling tank.

Figure 2. Insert for carbon-steel-tube pickling tank.

Tubing pickling 5% FICI pickling solution As needed... 

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