RU2046328C1 - Device for determining the degree of humid steam flow dryness - Google Patents

Abstract

FIELD: measurement technology; thermodynamic experiments. SUBSTANCE: device has steam pipe provided with pressure transducers and sampling unit. The device also has the reservoir covered with insulating layer provided with temperature pickups and two tubes. One tube is connected with sampling unit and the other communicates with measuring glass through a valve. EFFECT: enhanced reliability of the method. 1 dwg

Description

 The invention relates to the field of measuring the thermodynamic parameters of a wet steam stream, namely, the degree of dryness.

A device for determining the degree of dryness of a stream of wet steam, containing a portion of the steam pipe with sensors of static pressure, dynamic pressure and dynamic vacuum [1]
A disadvantage of the known device is the lack of mobility; the device is rigidly installed in the steam line and practically cannot be moved to another control point. The noted drawback significantly complicates the task of ensuring the accuracy of determining the parameters of wet steam by a known device (the device cannot be removed for verification) and the task of covering a site with several control points by one device.

 A device is also known for determining the degree of dryness of wet steam in a steam pipe of a once-through steam generator, comprising a sampler in the feed water channel and a sampler of the steam separator in the steam pipe. This known device implements a "salt" method for determining the degree of dryness of wet steam in relation to the salt content of the source feed water and the liquid phase of the stream of wet steam [2] By technical essence, this device is closest to the proposed one and is taken as a prototype.

 The disadvantage of the prototype is the limited object of its application. Thus, the known device is applicable only in the steam line of the steam generator to branch flow. It is not applicable in the steam line "on stream".

 The essence of the invention lies in the fact that the device comprising a steam line with a pressure sensor and a sampling unit, further comprises a vessel covered by a thermally insulating layer, equipped with a temperature sensor and two tubes, one of which is connected to a sampling unit, a valve on the second tube and a measuring cup, connected to the second tube.

 The drawing shows a schematic of the proposed device.

 The device comprises a pressure sensor 2 installed in the steam line 1, a sampler 3, a vessel 4, a tube 5 connecting the vessel with a sampler in the steam line, a measuring cup 6, a tube 7 with a valve 8, connecting the vessel to the measuring glass. The vessel is covered by a thermally insulating protective layer 9. A temperature sensor 10 is placed in the vessel body. The valve 11 provides the ability to disconnect the device from the steam line. The vessel and tubes are filled with steam condensate (water).

 The device operates as follows.

 To determine the degree of dryness, it is necessary to perform the following operations: measure the pressure in the steam line and the initial temperature of the water in the vessel, install a measuring cup 6 under the open end of the tube 7, open the valve 8 (liquid should be flowing from the cavity of the vessel 4 into the measuring cup 6, the speed of filling the measuring cup adjust the degree of opening of the valve 8 estimated time of filling the glass 60-70 s). The displacement of liquid into the measuring cup is ensured by vapor pressure. Steam enters vessel 4 from the steam line and the process is accompanied by an increase in the temperature of the liquid in the vessel. When approaching the filling level of the measuring cup to a predetermined mark, it is necessary to close valve 8 and measure the weight (volume) of the liquid (water) taken into the glass 6 from the vessel. After the time required for thermostating the water in the vessel (10-15 minutes), its final temperature is measured.

где П калориметрическая постоянная устройства;
t_кон конечная температура воды в сосуде;
t_нач начальная температура воды в сосуде;
С теплоемкость жидкой фазы пара (функция статического давления);
t_н температура насыщенных паров (функция статического давления);
G вес пробы;
r теплота парообразования (функция статического давления).The degree of dryness is calculated by the formula
χ

where P is the calorimetric constant of the device;
t _con final water temperature in the vessel;
t _nach initial temperature of the water in the vessel;
C the heat capacity of the liquid vapor phase (static pressure function);
t _n saturated vapor temperature (static pressure function);
G sample weight;
r heat of vaporization (static pressure function).

 The technical and economic efficiency of the developed device in the oil industry consists in the possibility of controlling the degree of dryness of wet steam in the steam pipelines of the steam and thermal exposure systems on the oil reservoir, which allows to increase oil recovery and reduce the energy consumption of the implementation of the steam and thermal exposure. The device was tested at the Karazhanbas oil field, design documentation for the manufacture of prototypes was developed.

An example of the implementation of measuring the degree of dryness of the proposed device is shown using experimental material: P 11.21; t _con 61.3 ^about C; t _beg 25.6 ^about With; G '1.0286 kcal / kg ^{° C} (pressure equal to 28 kg / cm ^2); t _n 231.06 ^about C; G 1 kg; r430.24 kcal / kg ^about C. As a result of the calculation according to the above formula, the calculated value of the degree of dryness χ 0.524 is obtained.

Claims (1)

 A device for determining the degree of dryness of a humid steam flow, comprising a steam line with a pressure sensor and a sampling unit, characterized in that the device further comprises a vessel covered by a heat-insulating layer, equipped with a temperature sensor and two tubes, one of which is connected to the sampling unit, and the other through valve with a measuring cup.

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