Experimental study and field application of surfactant-polymer flooding in offshore oilfield

Abstract

Restricted by the short life of the oil development platform and its high investment, offshore oilfield needs higher oil recovery rate in the early developmental stage so as to recover its investment fast. Therefore, polymer flooding method carried out in medium water cut period was proposed. The production performance improved through the use of polymer flooding in Bohai H oilfield, but became worse when the polymer flooding reached the end stage. The oil recovery increased by 10.5%. It is important to find a way to improve production performance other than polymer flooding. Therefore, this article optimizes surfactant-polymer flooding as the subsequent technology that enhances oil recovery. By using laboratory experiment to compare different experimental schemes, two important parameters including number of injection pore volume and injection timing were optimized. The research result was applied in field development of Bohai H oilfield. Based on the research results, this article concludes innovatively that surfactant-polymer flooding can enhance oil recovery significantly in offshore oilfield, and the number of injection pore volume and injection timing can affect the surfactant-polymer flooding obviously. It is reasonable when the number of injection pore volume is 0.3 PV for Bohai H oilfield; oil recovery can further increase if surfactant-polymer flooding is carried out in higher water cut period. The field application from 2013 to 2018 shows that the oil production performance of Bohai H oilfield can be improved significantly by using surfactant-polymer flooding; the daily oil production increased by about 1.25 times for average single well; and the oil recovery increment forecasted is 4.6% points. The research result can be used as an important reference for similar offshore oilfields to enhance oil recovery.

Experimental Study on Influencing Factors of Resistance Coefficient and Residual Resistance Coefficient in Oilfield Z

“…However, the short valid period of general measures does not meet the strategic needs of offshore oilfield development. Chemical flooding can solve the problem of water flooding to a great extent [1]- [6], in which polymer flooding can significantly improve water-oil mobility ratio and expand sweep volume of displacement phase; it can effectively block the channeling channel in high permeability layer and reduce the ineffective displacement of injected water. Therefore, polymer flooding has become an important way to enhance oil recovery in offshore oilfield development.…”

Remaining Oil Distribution Law and Potential Tapping Strategy of Horizontal Well Pattern in Narrow Oil Rim Reservoir with Gas Cap and Edge Water

“…Tapping the remaining oil is an important means to keep oil and water production stable during the development of reservoir [1]- [6]. However, the thin oil rim reservoir with gas cap and edge water is a special kind of reservoir and rarely seen at home and abroad [7] [8] [9].…”

Injection parameters optimization of crosslinked polymer flooding by genetic algorithm

“…Therefore, it is a key problem to select a reasonable injection concentration in the process of cross-linking polymer flooding Yin et al, 2013;El-Karsani et al, 2014). Genetic algorithm (GA) is one of the key technologies in modern intelligent computing and has been widely used in the field of reservoir development (Li et al, 2006;Liu et al, 2008;Li et al, 2012). Genetic algorithms operate directly on the structure of the object, and there is no derivation and limited function continuity.…”