Measuring method and device for MWD (measurement-while-drilling) spectrometer used for measuring oil gas components

Abstract

The invention relates to a measuring method and device for an MWD (measurement-while-drilling) spectrometer used for measuring oil gas components. The MWD spectrometer device comprises a parabolic mirror used for collimating a luminous point of a light source, and is characterized in that a sampling air chamber, a reference air chamber and a detector with four channels and four independent thermopiles are arranged at the back of the mirror, each channel is equipped with a filter plate and a transmission window, and the detector is installed on a semiconductor chilling plate. The MWD spectrometer device is advantaged in that the analysis speed is fast, the analysis cost is low, and the reappearance of the test results is good; the device can carry out on-line analysis by means of a current mature downhole signal transmission technology; the size is small, especially the cross section is small, and the device can be integrated into an MWD device conveniently; the power dissipation is low, the driving current of a novel infrared radiation light source is approximately 100mA, taking regard of pulse width modulation the duty ratio of which is 20-50%, the actual power is lower.

Description

(1) Technical field [0001] The invention relates to an optical system, in particular to a measuring method and device of a spectrometer while drilling for measuring oil and gas components. (2) Background technology [0002] Measurement while drilling is the most important means to efficiently develop complex oil and gas reservoirs, which is in line with the future development trend of the industry. The measurement-while-drilling of oil and gas composition based on spectral technology can effectively solve the real-time online measurement of oil and gas composition in the process of oil and gas drilling, and provide a reliable basis for drilling decisions. Compared with many traditional technologies, spectroscopic technology has technical advantages such as simultaneous detection of multiple components, fast analysis speed, and selective reaction. This patent designs a high-temperature dedicated infrared spectrometer system for the high-temperature and high-pressure closed m...

AI Technical Summary

Problems solved by technology

Both require grating dispersion and space separation, many peripheral supporting equipment, and large cross-section

There are defects in the technical implementation of the quantum cascade laser scheme: quantum cascade lasers are expensive and costly; the driving current is above 500mA, and the power consumption is large; the long-term stability performance test as a new device is not systematic; It is a far-infrared light source with a wavelength above 5um, and the Raman scattering generated is a far-infrared signal with a longer wavelength, which is extremely challenging for the optical system and detection system

[0010] Laser-based modulated absorption spectroscopy technology has extremely high sensitivity, and is now developed by some international large companies such as GE, E+H, NeoMonitor, etc. and developed in the petrochemical field for online analyzers of trace gases in ppm or even ppb levels , but the maximum operating temperature of laser diodes and detectors used in the near-infrared and mid-infrared bands is 60-80°C. Even with the addition of a temperature adjustment module, the operating temperature can be increased by up to 30°C, which still cannot meet the requirements

Images