Wu, Yongbin (PetroChina Co. Ltd.) | Li, Xiuluan (Research Inst. Petr. Expl/Dev) | Liu, Shangqi (Research Inst. Petr. Expl/Dev) | Ma, Desheng (Expl & Dev Rsch Inst Liaohe Co.) | Jiang, Youwei (Research Inst. Petr. Expl/Dev)
Thermal recovery technology particularly cyclic steam stimulation (CSS) is always an effective means to develop the conventional heavy oil reservoirs, which can be validated from literature. While most of the heavy oil reservoirs developed by CSS are the thick, well-deposited, high quality reservoirs and there are no much reports of producing oil from mid-depth oil reservoirs with large acquifers.
In this paper, according to the petrophysical properties and geologic characteristics of the target block F in Greater Fuld oilfield in Sudan, based on the oil test results, detailed 3D geologic model is established and the type well model for CSS and SF is extracted, to study the real performance with the real geological properties.
The development zone, the perforation strategies, the cylic steam injection quantity, the steam injection rate, soak time, and cyclic period are optimized for CSS. Based on the production performance of CSS, the optimal cycles of CSS followed by SF is determined. And the wellpattern and well spacing, the parameters of SF such as unit steam injection rate, steam quality, effects of bottom acquifer on the SF are also simulated and optimized. The simulation results indicate that the thermal recovery technique especially 4 cycles of CSS followed by SF can acquire satisfied performance, which shows an effective and economic future in the development of the heavy oil deposits in Greater Fula Oilfield.
Wu, Shuhong (Research Inst Petr Expl/Dev) | Min, Han (Greatwall Drilling Company, CNPC) | Ma, Desheng (PetroChina ) | Wu, Yongbin (RIPED, PetroChina) | Yu, Qian (Daqing Oil Field, PetroChina Co. Ltd.) | Chunli, Yao (Daqing Oil Field, PetroChina Co. Ltd.) | Dehuang, Shen (PetroChina )
Steam flooding, one of commercial technologies widely used to develop heavy oil reservoir, has brought reservoir engineer's attention to improve performance of waterflooding, light oil reservoir and enhance its oil recovery. In Cy reservoir of Daqing
oil field, a steam flooding project is successfully going on to enhance the oil recovery after waterflooding. Cy reservoir is a typical low-permeability, light-oil reservoir with depth of 1000m, an average permeability around 8 md and a typical porosity
of 16%, oil viscosity of 16~95mpa.s.
Cy reservoir came into development in 1995 under waterflooding. However, waterflooding has suffered from low water injectivity, poor sweep, and poor injector-to-producer communication. Only 10% of oil in place has been produced during 10
years' waterflooding. In 2007, steam flooding was utilized to improve the performance and enhance the oil recovery. The steam flooding project shows promising results. The response to steam injection is prompt and significant. The injectivity is
doubled and productivity is almost tripled. The oil-steam-ratio is around 0.3. The incremental recovery is predicted to be over 10%.
The paper will firstly brief production history of waterlfooding. Secondly, the paper will detail steam injection and analyze its performance and influence factors.The paper will also discuss mechanisms, strategies as well as barriers and difficulties to
high recovery of steam flooding in such waterflooding, light oil, low permeable reservoir andl also detail reservoir engineering study, such as development manner, injection and production system, and its physical and numerical simulation. The steam flooding project shows us that steam injection has great potential in improving injection and production profiles, increasing productivity and enhancing oil recovery.