ISO 21741:2020 固定源排放 用金汞齐陷阱对烟气中汞化合物的取样和测定
标准编号：ISO 21741:2020
中文名称：固定源排放 用金汞齐陷阱对烟气中汞化合物的取样和测定
英文名称：Stationary source emissions — Sampling and determination of mercury compounds in flue gas using gold amalgamation trap
发布日期：2020-11
标准范围
本文件描述了一种对固定源烟道气流中气相和固相汞进行采样和测量的方法。汞通常以元素（Hg0）和氧化（Hg2+）形式存在于烟气中的气相和固相中。在用过滤器去除固相（颗粒）汞之后，用金汞齐化捕集器等速或非等速捕获气相（气态）汞。由于金汞齐捕集器仅捕获气态元素汞，因此气相中的氧化汞(Hg2+)在金汞齐捕集器之前转化为元素汞(Hg0)。通过加热金汞齐化捕集器释放汞后，使用原子吸收光谱法(AAS)或原子荧光光谱法(AFS)测定气态汞的浓度。另外，在过滤器上等速收集颗粒汞，并在将颗粒汞溶解到溶液中后使用冷蒸汽AAS或冷蒸汽AFS测定浓度。烟气中汞的总浓度表示为气态和颗粒状汞浓度的总和。金汞齐法旨在短期（定期）测量0.01 μ g/m3至100 μ g/m3的气态汞，采样体积为0,005 m3至0.1 m3，采样气体流速为0.2 L/min至1 l/min。颗粒汞的测量范围通常为0.01 μ g/m3至100 μ g/m3，采样体积为0.05 m3至1 m3。
This document describes a method for the sampling and measurement of mercury of both vapour and solid phases on stationary source flue gas streams. Mercury generally exists as elemental (Hg0) and oxidized (Hg2+) forms, both in the vapour and solid phases in flue gases. The vapour-phase (gaseous) mercury is captured either isokinetically or non-isokinetically with a gold amalgamation trap after removing solid-phase (particulate) mercury with a filter. Because gold amalgamation trap captures only gaseous elemental mercury, the oxidized mercury (Hg2+) in the vapour phase is converted to elemental mercury (Hg0) prior to the gold amalgamation trap. The concentration of gaseous mercury is determined using atomic absorption spectrometry (AAS) or atomic fluorescence spectrometry (AFS) after releasing mercury by heating the gold amalgamation trap. Separately, particulate mercury is collected isokinetically on a filter and the concentration is determined using cold vapour AAS or cold vapour AFS after dissolving the particulate mercury into solution.The total concentration of mercury in flue gas is expressed as the sum of both gaseous and particulate mercury concentrations.The gold amalgamation method is intended for short-term (periodic) measurements of gaseous mercury ranging from 0,01 μg/m3 to 100 μg/m3 with sampling volumes from 0,005 m3 to 0,1 m3 and sample gas flow rate between 0,2 l/min to 1 l/min. The measurement range of particulate mercury is typically from 0,01 μg/m3 to 100 μg/m3 with sampling volume from 0,05 m3 to 1 m3.
标准预览图
