Online monitoring and analysis instrument for coal gangue flue gas

1、 Product Overview

The continuous online monitoring system for flue gas utilizes extraction condensation sampling, backscattering smoke concentration measurement, pitot tube flue gas flow velocity measurement, and computer network communication technology to achieve online continuous monitoring of pollutant emission concentration and total emissions from fixed pollution sources. At the same time, technical improvements have been made in response to the situation where domestic coal types are relatively diverse, coal quality changes greatly, pollutant emission concentrations are high, and flue gas humidity is high. and

Online monitoring and analysis instrument for coal gangue flue gas

The gas filter correlation method is to fill the measured gas in a gas filter cell, replacing the reference filter in the above method. This method can improve the absorption effect of the measured gas component on characteristic waves. This measurement system consists of five parts: the light source emits infrared light from a Nernst lamp; The measuring chamber has suction and filling holes, which provide a guarantee for the stability of the concentration of the gas components to be measured. The high-temperature tracing function can effectively prevent the condensation of water vapor and pollutants, which may interfere with the measurement results; The cutting wheel is mainly responsible for RF patterning of the beam signal; Gas filter cells and measurement filters for different gases are installed on the wheel. The rotation of the filter wheel and cutting wheel is powered by a brushless DC motor, and the measurement of each component is completed by the automatic control system sending control instructions; Install an amplifier in front of the photoelectric tube to improve the reliability of weak signal reception.

The positions of the tested gas filter cell and the measuring filter are controlled by the internal processor of the device. One measurement process can scan the tested gas multiple times to improve the signal-to-noise ratio of the signal and reduce measurement errors. The microprocessor can effectively handle various interferences; The method of subtracting the concentration of interfering components can effectively handle the spectral overlap of different tested components; The correction factor is used to handle the influence of interfering components on the absorption coefficient of the measured component.

1.3 Technical Analysis

①Smoke analysis.

The analysis technology used in the flue gas analyzer is a combination of single beam dual wavelength and gas filtering related technology. The gas filtering pool on the filtering wheel can achieve simultaneous measurement of different gases, and the interference parameter deduction technology is used to greatly improve the accuracy of the measurement results. It can also achieve high-precision continuous detection of eight gases, including carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, sulfur dioxide, methane, ammonia, and hydrogen chloride. The measurement range for carbon monoxide can reach 4000mg/m3, with an accuracy of 0.1%.

② Signal amplification circuit.

The signal amplification circuit is made using CMOS technology with a chopper stabilized zero combined multi-stage amplification mode. The main components include a multi way switch and an instrument amplifier. The signal amplification circuit has the advantages of high gain, fast response, and small input bias current, which can effectively reduce errors. It also has the function of automatic zeroing, increasing the accuracy and stability of measurement.

③ CEMS continuous emission monitoring system for flue gas.

Online monitoring and analysis instrument for coal gangue flue gas