标准摘要
[中文适用范围]： ISO 6978 的这一部分规定了一种测定天然气中总汞含量的方法，采用在高达 40 MPa 的压力下通过碘浸渍硅胶化学吸附的取样方法。 该取样方法适用于测定天然气中0.1μg/m至5000μg/m范围内的汞含量。 本方法适用于取样条件下硫化氢（绝对含量）小于20mg且液态烃凝析物总量小于10g/m3的取样气体体积。 通过测量汞蒸气在 253.7 nm 处的吸光度或荧光来确定收集到的汞。 注：ISO 6978-2 给出了一种适用于测定管道天然气汞含量的取样方法，该方法是在大气压下在金/铂合金线上混汞，汞含量范围为 0.01 μg/m 至 100 μg/m以及用于在 0.001 μg/m 至 1 μg/m 的高压（高达 8 MPa）下采样。 [外文原描述]： ISO 6978-1:2003 specifies a method for the determination of total mercury content in natural gas using a sampling method at pressures up to 40 MPa by chemisorption on iodine impregnated silica gel. This sampling method is suitable for the determination of mercury contents within the range of 0,1 microgram/m 3 to 5 000 micrograms/m 3 in natural gas. This method is applicable to sampled gas volumes containing less than 20 mg hydrogen sulfide and less than a total liquid hydrocarbon condensate of 10 g/m 3 under the sampling conditions. The collected mercury is determined by measuring the absorbance or fluorescence of mercury vapour at 253,7 nm.
英文名称Natural gas — Determination of mercury — Part 1: Sampling of mercury by chemisorption on iodine