Natural Gas Reinjection in a Heavy Oil Field Increases Foamy Oil Recovery

Author(s):  
X. Fei Sun ◽  
Y. Zhang ◽  
X. Duan ◽  
X. Li
2013 ◽  
Vol 318 ◽  
pp. 405-409 ◽  
Author(s):  
Ju Hua Li ◽  
Rong Bao ◽  
Bin Qin ◽  
Tao Jiang

The nature of injected gas dispersion in oil distinguishes foamy oil behavior from conventional heavy oil behavior. Unlike normal two-phase flow, it involves flow of dispersed gas bubbles with pseudo single phase. This paper presents the results of a numerical simulation study of the stability of foamy oil created by liberation of dissolved gas during natural gas huff and puff process. Through the history matching of labs test conducted by three series of various core tubes in numerical simulation, foamy oil impactions on recovery were discussed based on vertical heterogeneous model. The effects on the stability of foamy oil flow behavior were investigated by mobility ratio, viscous to gravity ratio, layer permeability contrast, vertical to horizontal permeability ratio and the transverse dispersion number in the paper. The results show that foamy oil stability increases with higher oil viscosity, higher injection gas density. The oil recovery decrease with the mobility ratio and the layer permeability contrast, while the oil recovery increase with the vertical to horizontal permeability ratio. This work demonstrates that the transverse dispersion number should be used to assess vertical or microscopic sweep efficiency. The study indicates that foamy oil in porous media during production is unstable, but it will be huge potentials to apply natural gas huff and puff for ultra-deep heavy oil reservoirs.


2021 ◽  
Author(s):  
Ali Reham Al-Jabri ◽  
Rouhollah Farajzadeh ◽  
Abdullah Alkindi ◽  
Rifaat Al-Mjeni ◽  
David Rousseau ◽  
...  

Abstract Heavy oil reservoirs remain challenging for surfactant-based EOR. In particular, selecting fine-tuned and cost effective chemical formulations requires extensive laboratory work and a solid methodology. This paper reports a laboratory feasibility study, aiming at designing a surfactant-polymer pilot for a heavy oil field with an oil viscosity of ~500cP in the South of Sultanate of Oman, where polymer flooding has already been successfully trialed. A major driver was to design a simple chemical EOR method, to minimize the risk of operational issues (e.g. scaling) and ensure smooth logistics on the field. To that end, a dedicated alkaline-free and solvent-free surfactant polymer (SP) formulation has been designed, with its sole three components, polymer, surfactant and co-surfactant, being readily available industrial chemicals. This part of the work has been reported in a previous paper. A comprehensive set of oil recovery coreflood tests has then been carried out with two objectives: validate the intrinsic performances of the SP formulation in terms of residual oil mobilization and establish an optimal injection strategy to maximize oil recovery with minimal surfactant dosage. The 10 coreflood tests performed involved: Bentheimer sandstone, for baseline assessments on large plugs with minimized experimental uncertainties; homogeneous artificial sand and clays granular packs built to have representative mineralogical composition, for tuning of the injection parameters; native reservoir rock plugs, unstacked in order to avoid any bias, to validate the injection strategy in fully representative conditions. All surfactant injections were performed after long polymer injections, to mimic the operational conditions in the field. Under injection of "infinite" slugs of the SP formulation, all tests have led to tertiary recoveries of more than 88% of the remaining oil after waterflood with final oil saturations of less than 5%. When short slugs of SP formulation were injected, tertiary recoveries were larger than 70% ROIP with final oil saturations less than 10%. The final optimized test on a reservoir rock plug, which was selected after an extensive review of the petrophysical and mineralogical properties of the available reservoir cores, led to a tertiary recovery of 90% ROIP with a final oil saturation of 2%, after injection of 0.35 PV of SP formulation at 6 g/L total surfactant concentration, with surfactant losses of 0.14 mg-surfactant/g(rock). Further optimization will allow accelerating oil bank arrival and reducing the large PV of chase polymer needed to mobilize the liberated oil. An additional part of the work consisted in generating the parameters needed for reservoir scale simulation. This required dedicated laboratory assays and history matching simulations of which the results are presented and discussed. These outcomes validate, at lab scale, the feasibility of a surfactant polymer process for the heavy oil field investigated. As there has been no published field test of SP injection in heavy oil, this work may also open the way to a new range of field applications.


2021 ◽  
Author(s):  
Jasmine Shivani Medina ◽  
Iomi Dhanielle Medina ◽  
Gao Zhang

Abstract The phenomenon of higher than expected production rates and recovery factors in heavy oil reservoirs captured the term "foamy oil," by researchers. This is mainly due to the bubble filled chocolate mousse appearance found at wellheads where this phenomenon occurs. Foamy oil flow is barely understood up to this day. Understanding why this unusual occurrence exists can aid in the transfer of principles to low recovery heavy oil reservoirs globally. This study focused mainly on how varying the viscosity and temperature via pressure depletion lab tests affected the performance of foamy oil production. Six different lab-scaled experiments were conducted, four with varying temperatures and two with varying viscosities. All experiments were conducted using lab-scaled sand pack pressure depletion tests with the same initial gas oil ratio (GOR). The first series of experiments with varying temperatures showed that the oil recovery was inversely proportional to elevated temperatures, however there was a directly proportional relationship between gas recovery and elevation in temperature. A unique observation was also made, during late-stage production, foamy oil recovery reappeared with temperatures in the 45-55°C range. With respect to the viscosities, a non-linear relationship existed, however there was an optimal region in which the live-oil viscosity and foamy oil production seem to be harmonious.


2015 ◽  
Vol 33 (7) ◽  
pp. 846-854
Author(s):  
X. Sun ◽  
Y. Zhang ◽  
C. Zhao ◽  
W. Li ◽  
X. Li

2012 ◽  
Vol 268-270 ◽  
pp. 547-550
Author(s):  
Qing Wang Liu ◽  
Xin Wang ◽  
Zhen Zhong Fan ◽  
Jiao Wang ◽  
Rui Gao ◽  
...  

Liaohe oil field block 58 for Huancai, the efficiency of production of thickened oil is low, and the efficiency of displacement is worse, likely to cause other issues. Researching and developing an type of Heavy Oil Viscosity Reducer for exploiting. The high viscosity of W/O emulsion changed into low viscosity O/W emulsion to facilitate recovery, enhanced oil recovery. Through the experiment determine the viscosity properties of Heavy Oil Viscosity Reducer. The oil/water interfacial tension is lower than 0.0031mN•m-1, salt-resisting is good. The efficiency of viscosity reduction is higher than 90%, and also good at 180°C.


2016 ◽  
Author(s):  
Ali Farog ◽  
Haytham A.Mustafa ◽  
Enas Mukhtar ◽  
Husham Elblaoula ◽  
Badreldin A. Yassin ◽  
...  

2014 ◽  
Vol 122 ◽  
pp. 94-107 ◽  
Author(s):  
Xiaofei Sun ◽  
Yanyu Zhang ◽  
Guoliang Cui ◽  
Xuewei Duan ◽  
Chunyan Zhao

2013 ◽  
Vol 734-737 ◽  
pp. 1434-1439 ◽  
Author(s):  
Gang Wu ◽  
Fu Ping Ren ◽  
Jing You ◽  
Ji Liang Yu ◽  
Ya Tuo Pei ◽  
...  

Based on the low-temperature and heavy oil reservoir of conventional injection well pattern separated two strains of oil degradation bacteria LC and JH which had satisfactory compatibleness with BaoLige oill field. In order to study the feasibility of enhancing oil recovery rate of the two strains, the experiment of huff and puff with 15 wells were carried out. The average concentration of bacteria increase from 4.7×102cells/ml to 8.1×106cells/ml. The average reduction of surface tension and viscosity is 33.1% and 31.9%. The accumulative total was 1163.2t. The ratio of input to output was 1:2.12. Microbial enhanced oil recovery can improve the low-temperature and heavy oil production status, which provide a effective method for the similar oil field.


Sign in / Sign up

Export Citation Format

Share Document