Automatic measuring instrument and measuring method for unconventional natural gas content

Patent metadata

Field	Value
Publication number	US-9709474-B2
Application number	US-201314766453-A
Country	US
Kind code	B2
Filing date	Oct 16, 2013
Priority date	Feb 7, 2013
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

An automatic measuring instrument for an unconventional natural gas content includes a parsing tank, a thermostatic water bath box, a gas collection measuring cylinder, a balance measuring cylinder, a liquid storage tank, a data acquisition and control system, an upper computer, and a lifting device for driving the gas collection measuring cylinder and the balance measuring cylinder to move relative to the liquid storage tank, wherein both the lower ports of the gas collection measuring cylinder and the balance measuring cylinder are placed below the liquid level of the liquid storage tank. The parsing tank is placed in the thermostatic water bath box. A gas guide tube A is connected to the parsing tank and the gas collection measuring cylinder. A gas guide tube B is connected to the balance measuring cylinder and the outside atmosphere is fed therein. By the adoption of the measuring instrument, the constant-pressure isasteric automatic continuous measurement of the content of natural gas contained in an unconventional natural gas reservoir sample is achieved. Moreover, the measuring instrument is simple in structure, reliable in measurement and analysis results, convenient in operation and high in measurement accuracy.

First claim

What is claimed is:

1. An automatic measuring instrument for an unconventional natural gas content, comprising:
a parsing tank, a thermostatic water bath box, a gas collection measuring cylinder, a balance measuring cylinder, a liquid storage tank, a data acquisition and control system and an upper computer, wherein the lower end of the gas collection measuring cylinder is open and the upper end thereof is sealed by a first sealing cover, wherein a first floating sheet is arranged in the gas collection measuring cylinder, wherein the lower end of the balance measuring cylinder is open and the upper end thereof is sealed by a second sealing cover, wherein a second floating sheet is arranged in the gas collection measuring cylinder, wherein both the lower ports of the gas collection measuring cylinder and the balance measuring cylinder are placed below the liquid level of the liquid storage tank, wherein the parsing tank is placed in the thermostatic water bath box and includes a tank body and a third sealing cover, wherein a temperature transmitter is arranged on the third sealing cover, wherein a first photoelectric liquid level sensor is arranged on the first sealing cover, wherein a second photoelectric liquid level sensor is arranged on the second sealing cover, wherein a first gas guide tube is connected to the internal space of the parsing tank and the internal space of the gas collection measuring cylinder, wherein a second gas guide tube is connected to the internal space of the balance measuring cylinder and external atmosphere, wherein a normally-opened electromagnetic valve is arranged on the first gas guide tube, wherein the first gas guide tube is also connected with an evacuation branch gas tube which is equipped with a normally-closed electromagnetic valve, wherein the temperature transmitter, the first photoelectric liquid level sensor, the second photoelectric liquid level sensor, the normally-opened electromagnetic valve, a normally-closed electromagnetic valve, and a driving device of a lifting device are electrically connected with the data acquisition and control system respectively, wherein the data acquisition and control system is electrically connected with the upper computer; and
a lifting device driving the gas collection measuring cylinder and the balance measuring cylinder to move up and down relative to the liquid storage tank.

2. The automatic measuring instrument for the unconventional natural gas content according to claim 1 , wherein the upper computer is an industrial touch screen or a computer provided with an embedded system.

3. The automatic measuring instrument for the unconventional natural gas content according to claim 1 , wherein a protecting cap is also arranged at the lower end of the gas collection measuring cylinder and the lower end of the balance measuring cylinder respectively, and an axial through hole is formed in the middle of each protecting cap, wherein the hole diameter of each of the through holes is smaller than the outer diameter of the first floating sheet and the outer diameter of the second floating sheet.

4. The automatic measuring instrument for the unconventional natural gas content according to claim 1 , wherein the lifting device comprises a driving device, a worm wheel and worm mechanism, a screw rod and a support, wherein the worm wheel and worm mechanism comprises a worm wheel and a worm which are meshed to each other; the driving device is a motor which is horizontally arranged, wherein an output shaft of the motor is connected with the worm through a transmission device; the screw rod is vertically arranged; the worm wheel is sheathed on the screw rod and is fixedly connected with the screw rod; the support is fixed on the liquid storage tank, and the support and the screw rod are assembled into a whole through threads; and the motor is electrically connected with the data acquisition and control system.

5. The automatic measuring instrument for the unconventional natural gas content according to claim 1 , wherein the lifting device comprises a driving device, a worm wheel and worm mechanism, a screw rod and a support, wherein the worm wheel and worm mechanism comprises a worm wheel and a worm which are meshed to each other; the driving device is a motor which is horizontally arranged, wherein an output shaft of the motor is connected with the worm through a transmission device; the screw rod is vertically arranged; the worm wheel is sheathed on the screw rod and is fixedly connected with the screw rod; the gas collection measuring cylinder and the balance measuring cylinder are fixed on the support, and the support and the screw rod are assembled into a whole through threads; and the motor is electrically connected with the data acquisition and control system.

6. The automatic measuring instrument for the unconventional natural gas content according to claim 4 or 5 , wherein the motor is a stepping motor or a linear motor.

7. The automatic measuring instrument for the unconventional natural gas content according to claim 1 , wherein a water drain valve is arranged at the bottom of the water storage tank.

8. A measuring method adopting the automatic measuring instrument for the unconventional natural gas content according to claim 1 , comprising the steps of:
(S1) configuring equipment before measurement, the upper computer controlling the normally-closed electromagnetic valve to be opened and the normally-opened electromagnetic valve to be closed through the data acquisition and control system, controlling the driving device of the lifting device to drive the liquid storage tank to ascend or drive the gas collection measuring cylinder and the balance measuring cylinder to descend, so that the liquid level in the gas collection measuring cylinder and the liquid level in the balance measuring cylinder raise, the first photoelectric liquid level sensor and the second photoelectric liquid level sensor transmitting liquid level parameters to the data acquisition and control system in real time, the data acquisition and control system transmitting the acquired parameters to the upper computer, when the liquid level in the gas collection measuring cylinder and the liquid level in the balance measuring cylinder reach a set upper limit value, the upper computer controlling the driving device of the lifting device to stop working, the normally-closed electromagnetic valve to be closed and the normally-opened electromagnetic valve to be opened;
(S2) placing the unconventional natural gas reservoir sample in the parsing tank and putting the parsing tank into the thermostatic water bath box, the temperature in the thermostatic water bath box being measured by the temperature transmitter, the temperature transmitter transmitting temperature parameters to the data acquisition and control system, and the data acquisition and control system transmitting the acquired parameters to the upper computer;
(S3) measuring the gas content, the natural gas being continuously separated out from the reservoir sample under a simulated downhole temperature environment and then entering the gas collection measuring cylinder through the first gas guide tube and the normally-opened electromagnetic valve, so that the liquid level in the gas collection measuring cylinder drops, and meanwhile, the liquid level in the balance measuring cylinder and the liquid level in the liquid storage tank raise thereupon, both the floating sheets in the gas collection measuring cylinder and the balance measuring cylinder moving along with the liquid level change, the first photoelectric liquid level sensor and the second photoelectric liquid level sensor transmitting the liquid level parameters to the data acquisition and control system in real time, the data

Assignees

• Petro China Co Ltd Southwest Oil And Gas Field Explor And Dev Res Inst
• Univ Southwest Petroleum
• Sichuan Kelite Oil And Gas Tech Co Ltd
• Petro China Co Ltd Southwest Oil And Gas Field Explor And Dev Res Inst

Inventors

• Du Jian

Classifications

• G01F23/292

  Light {, e.g. infrared or ultraviolet} · CPC title

• G01N7/14 Primary

  by allowing the material to emit a gas or vapour, e.g. water vapour, and measuring a pressure or volume difference {(determining urea G01N33/48742)} · CPC title

• G01N33/0016

  by regulating a physical variable, e.g. pressure or temperature · CPC title

• G01N7/16 Primary

  by heating the material · CPC title

• G01N33/241

  for hydrocarbon content · CPC title