Previous work has been done in depleted carbonated heavy oil fields located in north of Mexico to address the problem of lack or low oil production due to high crude oil viscosity using downhole chemical treatment. In order to make these mature wells economically attractive, this previously acquired experience was combined with venturi technology, resulting in a downhole hybrid system designed as an alternative method to conventional gas lift.
This paper describes an in-depth analysis and the benefits of applying a hybrid artificial lifting system based on the principle of venturi and downhole chemical treatment for improving production in mature heavy crude oil fields. This study also presents various aspects; such as, design, calculations, working principle, and sensitivity analysis. A brief description of the individual components of the system is included as well, showing that this can be modified according to the particular conditions and constrains of a well. A variation of this hybrid system was tested in a pilot project in a shallow well with promising results.
The innovations and technical contributions of this work consist of the following. Firstly, a hybrid lift system such as the one described here is beneficial for depleted reservoirs containing heavy crude oil since it allows for both: reduction of bottom hole pressure and reduction of oil viscosity at down hole conditions. Secondly, since this hybrid system is simple, deploying it into a well using a reduced diameter pipe such as coiled tubing avoids the use of a workover rig, which is crucial form the economical point of view.