Performance of Gel Treatments in Reservoirs with Multiscale Heterogeneity

Abstract

Spatially correlated permeability fields are usually generated by single-scale correlation. To overcome the limitations of single-scale permeability fields in describing real situation, permeability fields should be generated by multiscale correlation. Multiscale heterogeneity results in the existence of various permeability magnitudes and spatial distributions of permeability. Gel treatment is applied on the heterogeneous permeability fields realized by multiscale correlation. Performance of gel treatment has been shown to depend on permeability distribution and permeability values, which are determined by correlation length, variance, and number of scales. Generally, spatially-correlated permeability fields generated with longer correlation length, higher variance, and multiscale lead to higher improvement in the performance of gel treatment. In addition, longer application of preflush as waterflooding results in larger reduction of water-oil ratio when the gel treatment is applied to heterogeneous permeability fields after preflush.

Experimental evaluation and tomographic characterization of polymer gel conformance treatment

“…For managing produced water, it is desirable to avoid production of water onto the surface in the first place. Among a variety of techniques, polymer-gel technology has been used for the problem of water production Bai et al, 2015b;Bailey et al, 2000;Bryant et al, 1996;El-Karsani et al, 2014;Hasankhani et al, 2019;Jia et al, 2012;Karimi et al, 2014;Lee and Lee, 2013;Nguyen et al, 2012;Reddy et al, 2003;Seright, 1992Seright, , 1995Seright and Martin, 1993;Zitha et al, 2002). In this method, the polymer-gel solution is injected into the oil/gas wells to selectively block the water's path to the wellbore, and consequently to improve the conformance while minimizing the adverse effects of reservoir heterogeneity during waterflooding operations.…”

“…Most hydrocarbon reservoirs show complex geological heterogeneity due to the presence of rocks with a wide range of pore and grain sizes, different physical properties including permeability in particular, and the presence of natural features such as fractures. Reservoir heterogeneity, e.g., spatial variations in permeability, has been known as one of the reasons for low recovery of oil and early water production (Amir et al, 2019;Hasankhani et al, 2018;Heidari et al, 2018;Lee and Lee, 2013). As heterogeneity in permeability increases, flow paths become more complicated.…”

Study of heterogeneity loss in upscaling of geological maps by introducing a cluster-based heterogeneity number

“…This parameter has been studied for dispersion in porous media [6], recovery of oil reservoirs [7][8][9] and CO 2 storage in aquifers [10]. Other static measures included Lorenz coefficient [11], heterogeneity factor [12], sand index [13], coefficient of variation [14], standard deviation and correlation length [15,16].…”

Production Decline Analysis for Two-Phase Flow in Multifractured Horizontal Well in Shale Gas Reservoirs

“…Cho et al [19] presented the results of an experimental study of pressuredependent natural-fracture permeability in SGR and found that the effect of pressure-dependent natural-fracture permeability on shale gas well production was a function of the permeability of the matrix system. J. H. Lee and K. S. Lee [20] studied the multiscale heterogeneity in the existence of various permeability magnitudes and spatial distributions of permeability. Du et al [21] presented a new experimental method explaining the flooding tests in the low-permeability reservoirs.…”