Comprehensive Analysis Of Coke Oven Flue Gas And The Interference In SO₂ And NO_x Measurement

In this paper,a method based on GC-MS for comprehensive composition analysis of coke oven flue gas was proposed to measure the actual sample from a coke oven of J Corp in S province.Several factors were found in affecting the SO₂ and NO analysis by non-dispersive spectroscopic infrared method(NDIR),electrochemical method(EC),absorption method(IT)according to the existing waste gas emission standard.Considering the defects of existing standards,a new SO₂ concentration analysis method by ion chromatography was carried out in comparison with existing analytical methods.In this paper,a field investigation was implemented to collect the actual coke oven thermal parameters and coke oven flue gas samples from the reversing valve orifice plate boxes at the bottom of the coke oven,the coke/pushing side minor flues and the main flues using the new sampling tube to capture the liquid/solid phase contents in flue gas.The samples were tested by GC-MS after processed by Soxhlet extraction.Compared with liquid chromatography method,the GC-MS method has better resolution,and can much more easily and quantitatively analyze Benzopyrene in a broad sense.The coke oven flue gas was simulated by a gas fusion system in gradient distribution,and the differences were respectively compared by EC,NDIR and absorption methods.The experiment showed that the relative standard deviation(RSD)of the EC method,NDIR method and absorption method for SO₂ were 2.31%,1.17%,2.68%.When testing NO,EC method,NDIR method RSD were 2.07%,0.81%,NDIR method is better than EC method than absorption method;when using IR method,SO₂ sensor can respond to CH₄ input,CO sensor can respond to NO input,CO₂ sensor had a weak response to CO input.When the EC sensors were used,the NO sensor response to CO input,the SO₂ sensor responds to CO input,the SO₂ sensor responds to NO input.Under steam input conditions,the results of the NDIR and EC analysis are abnormal,but the absorption method and IC method can still obtain effective results.A new SO₂ analysis method based on ion chromatography which utilizes triethanolamine and hydrogen peroxide mixture as the absorption agent is proposed.Compared with the existing absorption method“Determination of Sulphur dioxide from exhausted gas of stationary source Iodine titration method”,experiments showed that the IC method is superior to the IT method in absorption performance,post-absorption stability,analytical repeatability and the RSDs were significantly lower than NDIR method,EC method and IT method.A multifunctional coke oven flue gas sampling device using a novel sampling tube was proposed.The device can accurately collect the solid and liquid components in the flue gas of the coke oven and at the same time SO₂ can also be accurately collected and oxidized to SO₄^2-ion for stable storage without the influence of condensation water.