A gas flow metering device and method based on a screw expander

Abstract

The invention provides a gas flow metering device and method based on a screw type expander. The flow metering device comprises a gas treating system, a flow transformation communication system and a monitoring end, wherein the gas treating system is used for reducing pressure of incoming gas flow in an upstream high-pressure pipe network, recycling pressure energy and then feeding the pressure energy to a downstream low-pressure pipe network; the flow transformation communication system is used for acquiring a gas flow parameter and a working state parameter in the process of reducing the pressure of the incoming gas flow and recycling the pressure energy of the gas treating system and on the basis of a running parameter of the gas treating system; the monitoring end is used for receiving data transmitted by the flow transformation communication system and is used for transmitting a data reading request to the flow transformation communication system. The gas flow metering device can measure the incoming gas flow at high precision.

Description

technical field [0001] The invention relates to the fields of gas flow metering and pressure energy recycling, in particular to a gas flow metering device and method based on a screw expander. Background technique [0002] With the further popularization of natural gas in urban and rural life and various industrial fields, the consumption of natural gas in my country has shown an obvious trend of increasing year by year. In 2016, the total consumption of natural gas in my country has exceeded 200 billion m 3 . Before the natural gas in the high-pressure pipeline network enters the user terminal (residential user or industrial user), it needs to be transported from the long-distance pipeline to the urban pipeline network (low-pressure pipeline network). During the transmission of natural gas from the high-pressure pipeline network to the user terminal, between the natural gas production plant and the long-distance pipeline, between the long-distance pipeline and the long-dis...

AI Technical Summary

Problems solved by technology

If the measurement error of the gas flow metering device used for gas delivery measurement is large, it will cause economic losses to gas sellers or users

[0003] The current gas flow metering devices are divided according to their working principles, mainly including ultrasonic type, turbine type, differential pressure type, Coriolis type, volumetric type, and vortex street type, etc., for fields that require highly precise control or measurement of gas flow ( Such as the sales of commercial gas (such as gas), because the traditional flow metering devices generally have the defects of many factors affecting the measurement accuracy and large measurement errors. Specifically, for example: when the ultrasonic flowmeter is measuring, the sensor Whether the contact with the pipe wall is good, the flow rate is too high / low, the uniformity of the measured fluid and other factors will have a great impact on the measurement accuracy; the turbine flowmeter is greatly affected by the fluid viscosity and other factors; the differential pressure flowmeter It is greatly affected by factors such as the medium (density, viscosity) and the straight pipe section (length, temperature, installation position); the Coriolis flowmeter is mainly suitable for low-density media (such as low-pressure gas), and In the measurement process, it is greatly affected by the interference of external vibration; the existing positive displacement flowmeter is greatly affected by temperature and viscosity, and its general volume is relatively bulky; , temperature fluctuations, etc. are greatly affected; etc.

Larger measurement errors, that is, inaccurate volume (flow) measurement will not only reduce the quality of products, but also cause economic losses to sellers or users.

In addition, the traditional flow metering device also has the defect of complex structure

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