Method for measuring dryness of downhole steam in thermal recovery horizontal well

Abstract

The invention provides a method for measuring the dryness of downhole steam in a thermal recovery horizontal well, which comprises the steps of: forming a capacitor by a two-phase mixed fluid of steam and water in a horizontal section in a mineshaft of the thermal recovery horizontal well, a capacitance sensor and a capacitance probe, and measuring the dryness of the steam in the horizontal section in the mineshaft of the thermal recovery horizontal well. The water phase in the steam and water two-phase mixed fluid, the capacitance sensor and the capacitance probe form into a circular capacitor, the water phase is taken as the negative electrode of the circular capacitor, the capacitance sensor and the capacitance probe are taken as the positive electrode of the circular capacitor, the capacitance sensor is used for measuring the voltage and commutating the liquid level height of the water phase, and the relationship between the liquid level height of the water phase and the voltage is as shown in the following formula so as to be capable obtaining the dryness of the steam in the horizontal section in the mineshaft of the thermal recovery horizontal well. The method has the characteristics of being extremely high in sensitivity to the water quantity, capable of measuring the downhole water content of the thermal recovery horizontal well, extremely high in sensitivity, small indryness measuring mean deviation which is less than 7%, convenient in application and operation and the like, thereby being widely applicable to the measurement technology of the dryness of the downhole steam in the oil thermal well.

Description

1. Technical field [0001] The invention relates to a method for measuring the dryness of downhole steam in petroleum thermal recovery wells, in particular to a method for measuring the dryness of downhole steam in thermal recovery horizontal wells. 2. Background technology [0002] Horizontal well steam injection oil recovery is an important technology to develop oil and gas fields and enhance oil recovery, especially for heavy oil oil fields. Compared with conventional vertical wells, horizontal wells have longer perforation intervals and larger oil layer openings, so lower driving forces can be used to increase oil recovery. The traditional measurement of downhole steam dryness in heavy oil thermal recovery vertical wells is mainly by measuring the downhole steam pressure, temperature, and flow rate, and using the relevant two-phase flow model to calculate the dryness in the wellbore, which has made a contribution to heavy oil recovery. This method also has the following ...

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Problems solved by technology

[0003] The purpose of the present invention is to provide a method for measuring the dryness of steam in the downhole of a thermal recovery horizontal well, which adopts a circular capacitance method, which can accurately measure the height of different liquid levels in the horizontal section and solve the problem of steam dryness in the horizontal section of the horizontal section of the thermal recovery of heavy oil. Untestable Technical Difficulties

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