2017_EJRNL_PP_MEHDI_MADHI_1.pdf
Terbatas  Suharsiyah
» Gedung UPT Perpustakaan
Terbatas  Suharsiyah
» Gedung UPT Perpustakaan
One of the most severe problems during production from heavy crude oil reservoirs is the formation of asphaltene precipitation and as a result deposition in the tubing, surface facilities and
near wellbore region which causes oil production and permeability reduction in addition to rock
wettability alteration in the reservoir. So one of the economical ways to prevent such incidents is
using the chemicals which are called asphaltene inhibitor.
In this study, the influence of three commercial inhibitors, namely; Cetyl Terimethyl Ammonium
Bromide (CTAB), Sodium Dodecyl Sulfate (SDS), Triton X-100 and four non-commercial (Benzene,
Benzoic Acid, Salicylic Acid, Naphthalene) inhibitors on two Iranian crude oils were investigated.
This study extends previous works and contributes toward the better understanding of interactions
between asphaltene and inhibitor. Effect of functional groups and structure of inhibitors on
asphaltene precipitation were studied and it seems clear that the nature and polarity of asphaltene
(structure and amount of impurities presented) has a significant impact on the selection of inhibitors. asphaltene dispersant tests and Core flood tests were designed for evaluation of inhibitors
in static and dynamic conditions. The results revealed distinguished mechanisms for asphaltene
solubilization/dispersion (such as hydrogen bonding, pep interaction and acid-base interaction)
and influence of additional side group (OH) on inhibition power of inhibitor.
During the experiments, it was found that increasing inhibitor concentration may lead to the
self-assembly of inhibitor and declining of asphaltene stabilization. So, finding optimum concentration of inhibitor with high efficiency and available at a reasonable price is very important. The
results suggest that 600 ppm of CTAB and 300 ppm of SDS were approximately optimum concentrations for the studied crude oils. One of the most important findings that differ from previous
studies is the revelation of the mechanism behind the SDS/asphaltene behavior in various concentrations of inhibitor. Effect of chosen inhibitors on asphaltene precipitation and consequently
deposition in porous media was studied, and then experimental data were modeled for evaluation
of permeability impairment mechanisms. Permeability revived after inhibitor squeezing and cake
formation mechanism played an important role in permeability reduction before and after treatment in porous media. The findings can also be applied to prediction of future behavior of reservoirs in oil field scale and evaluation of formation damage in the different period of production if
needed any treatment process.