ANALYSIS AND CHARACTERIZATION OF NIGERIAN WAXY CRUDE
IGWILO KEVIN *
Federal University of Technology, Owerri, Nigeria
ONWEGBUCHULEM CHIBUNMA
Madona University, Okija, Nigeria
OHIA PRINCEWILL
Federal University of Technology, Owerri, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Wax deposition is the major flow assurance challenge in production facilities in the Niger delta. This is because Nigerian crude oils are waxy. It has been the focus of research to profer effective predictive and preventive solutions to a problem that has been tackled with curative methods for decades. This work investigated paraffinic wax deposition using laboratory tests, field simulation with PipeSim: A pipeline simulator, and equilibrium correlations from Won, Chung, and Coutinho’s works. The tests gave wax content results of 3.73% and 3.45% for samples I and III while field simulation gave results of 3.71% and 3.49% for samples I and III, producing a good match when compared against the test results with a difference of less than ±0.05%. Calculations with Won, Chung and Coutinho correlations in a MathLab programe gave results of 0.996, 0.974, and 0.809 respectively for the sample I and results of 0.776, 0.587 and 0.751 respectively for sample III. This indicates that the Won model over estimates wax deposition compared with the more recent Chung and coutinho models.
This paper therefore recommends the use of PipeSim simulation package for wax deposition determination and prediction especially in the absence of laboratory data in addition to properly scheduled pigging and solvent injections to check wax deposition in facilities handling waxy crude oil.
Keywords: Flow assurance, wax deposition, laboratory test, PipeSim, simulation, waxy crude oil, Niger Delta and equilibrium correlation