Reaction device and method for correcting concentration of biomass combustion indicator in snow ice

Abstract

The invention relates to a reaction device and method for correcting the concentration of a biomass combustion indicator in snow ice. The device comprises two compressed N2 input ports and an O2 input port, each compression N2 pipeline is provided with a flowmeter, a reagent bottle containing 30% of H2O2 (weight) aqueous solution, a low-pressure mercury lamp ultraviolet light source, an OH free radical generator, a flow reaction cavity, a Mega-Ray simulation solar light source, a sample disc, a thermometer and a salicylic acid sampling head. The device and the method are used for researching the stability difference of various combustion emission indicators under different OH free radical concentrations, reaction time and reaction temperatures, and calculating a secondary reaction constant of the combustion emission indicators, calculating the initial settlement concentration of the biomass combustion indicator in the snow ice sample, and eliminating the influence of the biomass combustion indicator in the snow due to the oxidation of OH free radicals as much as possible.

Description

technical field [0001] The invention relates to a reaction device and method for correcting the concentration of biomass combustion indicators in snow and ice, belonging to the field of snow and ice chemistry. Background technique [0002] As a good carrier of climate and environmental information, snow and ice have been widely recognized. Snow and ice not only record natural change information, but also record the impact of human activities on the climate environment. A large number of studies have shown that greenhouse gases emitted by biomass burning and carbonaceous aerosols such as black carbon and brown carbon can significantly change the chemical composition of the atmosphere, thereby disturbing the atmospheric circulation pattern and affecting global climate change. After the carbonaceous aerosol settles on the surface of snow and ice, it can significantly reduce the albedo of snow and accelerate the melting of snow and ice. At the same time, due to the unique low-...

AI Technical Summary

Problems solved by technology

However, recent studies have shown that some organic tracers commonly used in source apportionment react to a certain extent in the presence of atmospheric oxidants (OH radicals, etc.), leading to changes in their concentrations during atmospheric transport, deposition and storage. In addition, studies have pointed out that levoglucosan is semi-volatile when it exceeds 20°C, and gas-phase oxidation will greatly shorten its residence time, especially under certain conditions such as high temperature in summer, its atmospheric life may even only 1-2 days

Therefore, using levoglucosan as an indicator for source apportionment research may underestimate the contribution of biomass combustion emissions to a certain extent, which will have a greater impact on the photochemical reaction rate and accuracy of quantitative source apportionment results.

[0004] So far, the research on the stability of combustion indicators such as levoglucosan in snow and ice medium is still blank.

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