Transporting of high paraffinic crude oil through pipelines is accompanied by the formation of a large amount of asphaltene-resin-paraffin deposits, corrosive destruction of bottom of the pipe, particularly at parts with its complex configuration and changing relief.
||Inhibitor properties||Hydrocarbon soluble||Water-soluble|
|1||Corrosion protection||Creates a strong and long-term protective film on the surface of the pipeline at any water cut||Creates a passivate film not over the whole surface of the pipeline. The film is very sensitive to changes in pH and the presence of corrosive components in bottom water|
|2||Removal of asphaltene-resin-paraffin deposits (ARPD)||Removes. It has high washing and detergent-dispersant properties||Do not remove. Do not possess washing and detergent-dispersant properties|
|3||ARPD inhibition||Possess. Reduces the amount of ARPD that precipitated in the pipeline||Does not possess. Can stimulate the formation of solid ARPD and its precipitation in the pipeline|
|4||Dispersant properties||Possess. Reduces the temperature of the onset of crystallization of solid paraffins||Does not possess|
|5||Removal of mineral salts||Possess. At a constant feed into the pipeline effectively washes off the mineral deposits||Does not possess. In the case of inorganic base of the inhibitor it increases the amount of mineral salts in the bottom water|
|6||Removal of clay-sand contaminants||Possess. At a constant supply into the pipeline for a long time keeps the clay-sand impurities in the fluid||Does not possess|
|7||Increasing the amount of transferring oil||Increase. Because of supplying of working solutions in the oil or kerosene and adding ARPD, that were washed away from the pipe walls, into counted crude oil||Does not contribute|
In the production of waxy oils, serious problem that causes complications at the oilfield equipment and pipelines is the formation of asphaltene-resin-paraffin deposits.
The reasons of the formation of asphaltene-resin-paraffin deposits in the oilfield equipment and pipelines are: violation of the hydrodynamic gas-liquid equilibrium of the system while reducing the pressure in the bottom hole; lowering the temperature in the reservoir and the wellbore; changing the velocity of the gas-liquid mixture and its individual components; intensive gas emission; changing the composition of hydrocarbon in the hydrocarbon phase produced fluids; changing in the volume ratio in the liquid phases (oil, water). These factors are changing continuously in the oilfield equipment and pipelines: in an oil well - from the bottom to the mouth, and oil pipelines - from the central area to the periphery. Therefore, the number and nature of the deposits in the oilfield equipment and pipelines are not permanent.
The practice of oil production at the oil fields shows that the main places of accumulation of asphaltene-resin-paraffin deposits in the oilfield equipment and pipelines are well pumps, tubing, flowlines (tail lines) oil pipelines from the wells to the manifold, equipment, pipelines and tanks of gathering and treatment of produced fluids. Formation of asphaltene-resin-paraffin deposits is enhanced in the pipelines flowlines when the ambient temperature
Formation of asphaltene deposits in the oilfield equipment and pipelines leads to a sharp decline in performance of oilfield equipment and pipelines and the efficiency of the pumping systems. The final result of the formation of asphaltene-resin-paraffin deposits in the oilfield equipment and pipelines are significant financial losses of oil companies related to the reduction in the number of crude oil, the cost of measures to clean up the oil-field equipment and pipelines and purchase for this purpose of expensive chemicals and solvents.
Struggle against asphaltene-resin-paraffin deposits in the oilfield equipment and pipelines is conducted on two fronts: prevention of scale formation and removal of already formed deposits. Compositions for removing asphaltene-resin-paraffin deposits of oil field equipment and pipelines, typically include active additives and solvent. Active additives (or, in other words - the chemicals in these formulations) should have higher absorption energy than asphaltene-resin-paraffin deposits formed in the oilfield equipment and pipelines. This is a necessary condition for, firstly, for preventing adsorption of asphaltene-resin-paraffin components forming in the oilfield equipment and pipelines, and, secondly, to prevent re-deposition of asphaltene-resin-paraffin deposits in the tubing and oil wells in the bottomhole formation zone.
As chemically active additive for the effective removal of asphaltene-resin-paraffin deposits of oil field equipment and pipelines, is efficient to apply hydrocarbon soluble corrosion inhibitors of DEFENDER series. The main advantage over similar products is a complex action. One reagent performs several functions, namely: inhibitor of asphaltene-resin-paraffin deposits on the surfaces of oilfield equipment and pipelines; reagent for removing asphaltene-resin-paraffin deposits of oil field equipment and pipelines; reagent for removing (rinsing) the mechanical mineral deposits of oil field equipment and pipelines; corrosion inhibitor of oil field metal equipment and pipelines. Application of reagents does not require for special stop wells needed in the application of other formulations of similar purpose.