Production performance analysis of heavy oil recovery by cyclic superheated steam stimulation

In this paper, a novel model is proposed for heated radius calculation and production performance analysis of cyclic superheated steam stimulation (CSHSS) wells. Firstly, the heated area after superheated steam (SHS) injection is distributed into three sub-areas whose heated radius are derived respectively. Next, a semi-analytical model for production performance analysis is proposed by using time discretization technique. After validation of the proposed model, production performance of CSHSS wells is analyzed in detail. The results indicate that the positive effect of residual heat on cyclic productivity improvement is offset by pressure drop and oil saturation drop. The constant pressure production (CPP) is found to be only a special case of the constant oil production (COP). Both of the cumulative oil production and thermal efficiency increase with the increase of constant oil production rate (COPR). The higher the COPR, the steeper the average pressure curve at its early stage. This paper presents basic reference for engineers in heated radius evaluations after SHS injection as well as performance estimations of CSHSS wells. (C) 2017 Elsevier Ltd. All rights reserved.