Loading...

Improving the Remediation Process of Asphaltene Deposits in the Well Facility of Koupal-Bangestan Oil Reservoir

Bagherian, Mahmood | 2021

528 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 53753 (06)
  4. University: Sharif University of Technology
  5. Department: Chemical and Petroleum Engineering
  6. Advisor(s): Ayatollahi, Shahaboddin; Ghotbi, Cyrus
  7. Abstract:
  8. Crude oil production could cause the thermodynamic equilibrium of the crude oil to be disturbed in the well column which results in asphaltene precipitation and deposition. The thickness of the deposited material grows over time until it completely blocks the well column.Due to the hard and insoluble nature of deposited asphaltene, the two main chemical and mechanical methods are found to be more effective. It should be noted that the actual organic sediments in the piping are not pure and consist of three components: asphaltene, resin and paraffin. Therefore, it is very important to know the composition of the deposited material before selecting the appropriate chemical solvent.The samples received from Koupal Bangestan field are of asphaltene deposit type, therefore it is necessary to use an aromatic solvent to dissolve and disintegrate them. Experiments have shown that the asphaltene content of these samples is very dense and somewhat old that aliphatic solvents are not able to dissolve them totally. It appears that at the time of production, the flow of oil along the deposited materials in the production line washes the components of the sediment that could be dissolved into the aliphatic solvents, which causes these solvents to be less efficient during the remediation.Among aromatic solvents, xylene was selected because it has excellent solubility and less safety challenges than toluene and benzene. In addition, the presence of aromatic solvents does not have the problem of incompatibility with the crude oil itself. Afterall, attempts were made in this research to improve the efficiency of xylene using industrial polar additives. During this laboratory work, activities aimed at optimizing the chemical solvents to be used to remediate several asphaltene samples collected from the Koupal field (aged, dry, wet, and fresh). Among the polar additives, alcohols, cyclohexanone and dimethylformamide were investigated which indicates that dimethylformamide solvent had the best performance. By increasing or decreasing the percentage of this component along with xylene, an optimal solvent can be obtained depending on the type of deposited asphaltene. For example, a combination of 80% xylene and 20% dimethylformamide, had the best effect on the sample dispersion for the case of DADW49, and for synthetic sample tablets, FADW49, a combination of 70% xylene and 30% dimethylformamide, had the best effect on portioning of sediment particles
  9. Keywords:
  10. Asphaltene Deposition ; Solvents ; Xylene ; Clearance ; Advanced Solvent ; Aromatic Solvent ; Well Column

 Digital Object List

 Bookmark

No TOC