System and method for improving injection capacity of polymer injection well on basis of electromagnetic wireless monitoring

Abstract

The invention relates to a system and a method for improving the injection capacity of a polymer injection well on the basis of electromagnetic wireless monitoring. The system is characterized by comprising a downhole system and a ground system; the downhole system is arranged under the polymer injection well, and the ground system is arranged outside a wellhead of the polymer injection well. Themethod includes monitoring bottom hole pressure data of the polymer injection well by the downhole system, and transmitting electromagnetic signals to the ground system according to the bottom hole pressure data; receiving the electromagnetic signals to obtain actual bottom hole pressure data by the ground system, and adjusting wellhead injection rates of the polymer injection well according to the bottom hole pressure data. The system and the method have the advantages that bottom hole pressures of the polymer injection well can be monitored in real time, the wellhead injection rates of polymer solution can be reasonably adjusted in real time under the condition that bottom hole pressure conditions can be mastered in real time on the premise that the bottom hole pressures are guaranteed against being higher than formation fracture pressures, and accordingly the injection capacity of the polymer injection well can be effectively improved.

Description

technical field [0001] The invention belongs to the field of oil field development and production, and in particular relates to a system and method for improving the injection capacity of a polymer injection well based on electromagnetic wave wireless monitoring. Background technique [0002] As an important development method, polymer flooding has been widely used in oilfield development and achieved good results. The injection capacity of polymer injection wells is an important indicator for rational allocation of production and injection to ensure the effect of polymer flooding. How to improve the injection capacity of polymer injection wells has always been an important issue that researchers have been concerned about. The injection capacity is closely related to the injection pressure. In the normal injection process, the bottom hole pressure is required not to be higher than the formation fracture pressure to eliminate the risk of the formation being fractured. Therefo...

AI Technical Summary

Problems solved by technology

However, in the actual mine field, due to the complexity of the wellbore string of the polymer injection well, it is difficult to maintain the conventional pressure gauge that relies on the cable transmission signal for a long time at the bottom of the well, and the bottom hole pressure monitoring data is scarce. The maximum wellhead pressure converted along the wellbore is used to control the injection rate

The problem of controlling the injection process by this method is obvious. The injection rate of the polymer injection well cannot reach the distribution due to the high wellhead pressure, but the actual bottomhole pressure is unknown. Due to the pressure loss along the wellbore Extensive and complex, the bottom hole pressure may be far from the level close to the fracture pressure of the formation, which may objectively cause the loss of injection capacity

As a result, formation energy cannot be replenished effectively in a timely manner, and the effect of polymer flooding is bound to be affected.

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