IN EMERGENCY SITUATIONS HYBRID TECHNOLOGIES CAN EXTEND THE LIFE OF EOR PROJECTS
. During the implementation and development of steam injection projects, it is common to face problems such as channeling, overriding, and production of acid gases. The presence and intensity of these problems are associated with the following three factors:
- Drastic variation of permeabilities.
- The difference in densities between the reservoir fluids and the injected fluids.
- The occurrence of chemical reactions between hydrocarbons and steam.
Even so, the joint injection of additives with steam has consolidated the concept of hybrid technologies with the purpose of counteracting the effect of these obstacles or giving them a new perspective. Generally speaking, hybrid technologies in emergency situations make it possible to extend the useful life of EOR projects.
THE USE OF DEVELOPED TECHNOLOGIES: IMPACTS AND CHALLENGES
To begin with, it is important to highlight that part of the previously mentioned problems can be mitigated by improving the efficiency of steam sweeping and propagation. Based on this, according to studies, the injection of additives such as foams and polymeric gels generates effects such as blocking zones with preferential permeability, reducing vapor mobility, increasing sweep, and reducing heat losses.
Moreover, such a chemical agent can be injected in a preformed form or its formation can occur in situ.
On the other hand, the main challenges with respect to this type of technology are associated with the thermal and chemical degradation that the blocking agent may face during the process. The development of materials resistant to typical operating conditions is a major focus of research.
Failing that, the generation of steam by conventional equipment produces a considerable amount of combustion gases. But, in order to decrease such emissions to the atmosphere while simultaneously exploiting their benefits at the reservoir level, the injection of nitrogen and carbon dioxide along with saturated steam represents a possible advantage of using hybrid processes.
BENEFITS OF RESERVOIR GASES
The presence of gases in the porous medium provides an additional source of pressurization, thus generating greater expansion of the steam chamber, increased and accelerated hydrocarbon production, and decreased water cut.
Likewise, the major challenges in the field of hybrid technologies are focused on the optimization of the injection scheme, the gas injection rates and the surface facilities necessary for the storage and treatment of the gases at the generator outlet.
If, on the other hand, we delve into their ability to modify the properties of the crude oil, the injection of solvents and catalysts produces an in situ enhancement of the hydrocarbons present in the porous medium. This is because they are diluted in the oleic phase, improving their mobility by reducing viscosity and decreasing the vapor volume required for recovery.
In contrast, catalysts alter the effects of aquathermolysis reactions, inhibiting the production of hydrogen sulfide and carbon dioxide, and promoting the formation of lower molecular weight hydrocarbons. In this way, this process allows not only to generate an increase in production, but also to produce crude oil with a higher commercial value.
Finally, the aforementioned technologies make it possible to extend the life of thermal recovery projects, giving added value to waste such as greenhouse gases and encouraging the current concept of circular economy models
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