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Development Of Infrared Absorption Methane Concentration Alarming Device

Posted on:2012-12-17Degree:MasterType:Thesis
Country:ChinaCandidate:Y L HuangFull Text:PDF
GTID:2218330368977681Subject:Measuring and Testing Technology and Instruments
Abstract/Summary:PDF Full Text Request
To ensure safety in coal mines has been the focus of the energy industry. As a typical representative of coal mine accidents, gas explosions which threaten the major coal mine production are a serious safety hazards. In order to take preventive measures to prevent the gas explosion accidents happed, domestic and foreign enterprises and research institutes developed a variety of alarming instruments on the basis of different monitoring methods and principle. However, due to relating technical reasons, In China the accuracy of coal mine gas alarming equipment for measurement is not high, and in poor stability at present.This paper studied methane concentration alarming device based on infrared absorption of a high precision and high stability for solved this problem. Methane is the main component of gas, which has the selective absorption characteristics of infrared radiation, whose absorb intensity of radiation form a specific function with the concentration of methane. It makes use of the infrared absorption detector sensor IR32BC of methane as a sensitive detection unit. Designed circuit diagram of IR light source modulation and sensor output signal disposal, It transforms intensity of the absorption of infrared radiation into a voltage signal, using TI's low power MCU MSP430F149 as the data processing unit, to realize the concentration calibration, collection signal, processing of digital filter, concentration calculations, digital display, frequency output function by microcontroller control. Infrared absorption methane concentration alarming device is comprised of microcontroller systems, light modulation module, signal conditioning module, digital display module, sound and light alarm module, remote control receiving module, standard output module interface circuit. Alarming device with microcontroller systems as the core, when methane concentration is 0~5%, the alarming device output 200~1000Hz frequency signal for monitoring system. When the concentration of methane in the environment is greater than or equal to the concentration limit set threshold, the alarming device will respond to sound and light alarm program, issued a harsh warning sound and a certain frequency of flashing light signals, to achieve early warning effect. Some compensation measures were made through hardware and software to the alarming device output signal nonlinear caused by environment disturbance, the zero drift and sensitivity drift caused by temperature to effectively improve the accuracy and reliability of the alarming device .A lot of measurement experiments of multiple points of gas concentration were carried out in the methane gas concentration alarming device , the analysis of experimental results showed that the infrared absorption alarming device meet the standard needs of methane concentration testing in industrial and coal mine with great practical application value.
Keywords/Search Tags:Methane, Infrared absorption principle, Gas concentration alarming
PDF Full Text Request
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