Identification and Treating of Downhole Organic Deposits

Abstract

Cost-effective oil production of wells that are known to have a history of downhole organic scale deposition is possible when a program of identification, testing, and chemical application is correctly instituted. Stimulation of production can result if there is available crude and pressure in the formation being bottled up by organic scale deposits. Removal of these "roadblocks' will allow the migration of additional crude. It is much cheaper to remove the roadblock, instead of building new roads, i.e., fracturing. There are two different types of organic deposits or scale. One is composed primarily of paraffin and the other of asphaltenes. Both paraffin and asphaltenes are natural constituents of most crude oils and their presence is not necessarily a cause for alarm. Only if the well seems to have problems is an investigation warranted. With the different constituency of the deposits comes the requirement to treat them in a different manner.

Heavy Organic Deposition and Plugging of Wells (Analysis of Mexico's Experience)

“…As temperature drops, larger amounts of sediments are detected reaching to a maximum at 20-30"C. Below this temperature we notice a decrease in the amount of sediments. A possible explanation for this may be the fact that paraffin/wax at temperatures close to the 354 freezing point are soft [20]. Therefore, coalescence of particles is likely to occur resulting in an increase of the volume fraction of the paraffin deposit.…”