Prediction of density and viscosity of bitumen

Abstract

It is well known fact that temperature and pressure significantly affects density and viscosity of bitumen. The present work utilizes Gene Expression Programming (GEP) approach to develop models to predict density and viscosity of bitumen. To evaluate the accuracy of proposed GEP based models, results reported by various researchers were utilized. This includes test results regarding Athabasca, Cold Lake and Gas free bitumen. The developed GEP based models were compared with the conventional empirical regression equations. The statistical analysis indicates that GEP based models work better than other existing models for density and viscosity of bitumen.     

PSO-ANFIS modeling of viscosity for mixtures of Athabasca bitumen and a high-boiling n-alkane

The bitumen and heavy oil reservoirs are more in number than light crude oil reservoirs in the world. To increase the empty space between molecules and decrease viscosity, the bitumen was diluted with a liquid solvent such as tetradecane. Due to the sensitivity of enhanced oil recovery process, the accurate approximation for the viscosity of mentioned mixture is important. The purpose of this study was to develop an effective relation between the viscosity of Athabasca bitumen and heavy n-alkane mixtures based on pressure, temperature, and the weight percentage of n-tetradecane using the adaptive neuro-fuzzy inference system method. For this model, the value of MRE and R² was obtained as 0.34% and 1.00, respectively; so this model can be applied as an accurate approximation for any mixture of heavy oil with a liquid solvent.     

垦东12块油藏采油方式优选及工艺研究

新滩油田垦东12油藏为浅海油田，油井为水平井厦定向井，油稠。为研究和优化设计该区块油井机采方式及其工艺，根据油藏特点系统论证了各种采油方式对该油藏的适应性．优选出电潜泵生产是唯一可行的机采方式。针对稠油特点，通过实验研究得出泵下掺降粘剂是该油藏最经济、有效、易于实施的降粘工艺，实验选择降粘剂为SB-2。进而对该油藏各井电泵生产的工艺参数进行了设计。生产动态预测结果表明，该油藏油井采用电潜泵生产并辅助以降粘荆降粘、泵下掺液量12～17m^3／d的条件可满足油井配产要求。     

Investigation and quantifying effect of dispersion on oil recovery in the process of viscoelastic polymer flooding using numerical method

In this study an existent mathematical model was implemented to investigate the effect of dispersion on oil recovery of core-flood experiments in process of viscoelastic polymer flooding as a tertiary stage of enhanced oil recovery. Discretized forms of equations of pressure, saturation, and concentrations were obtained and solved by implicit in pressure and explicit in saturation and concentrations with considering effect of time step on solution. Furthermore, a new procedure was presented to solve polymer concentration equation by trial and error. The results showed that dispersion phenomenon reduces displacement efficiency of viscoelastic polymer flooding.