Comparison of Development Effects for Two Different Combined Well Patterns with Horizontal Wells and Vertical Wells

DOI: 10.14800/IOGR.447

Abstract

In recent years, horizontal wells have been widely utilized in low permeability reservoirs of China. Normally horizontal wells are deployed combined with vertical wells, in which way effective injection-production well network system could be established. However, horizontal wells could be water injectors as well as oil producers and the same is true for vertical wells. The adoption of which kind of combined well pattern has been in dispute for a long time. In response to this issue, a novel physical simulation system is utilized to contrast the development effect of two well patterns with horizontal wells and vertical wells together. By comparing pressure gradient and flow velocity, the better scenario can be selected. If the horizontal well is not fractured, well pattern of horizontal wells as injectors with vertical wells as producers has a remarkable advantage. While the horizontal well is fractured, well pattern of horizontal wells as producers with vertical wells as injectors has a clear advantage. From another perspective to analyze the result, if an oilfield needs horizontal well to inject water for vertical wells, then the horizontal well is suggested not to be fractured. If an oilfield needs horizontal wells to produce much more oil with vertical injection wells, then horizontal wells with multiple hydraulic fractures could obtain better effect. As a rule of thumb, deployment of horizontal wells as oil producers is more common in oilfields.