- P-ISSN 1225-0163
- E-ISSN 2288-8985
천연가스는 산업의 발전으로 인하여 수요가 계속 증가하고 있어 도입물량 부족 현상이 일어나수급이 점차 불안정해질 것으로 예상된다. 액화천연가스 외에 파이프라인 천연가스 및 대체 천연가스등 다양한 형태의 가스 도입과 개발로 수요를 충당해야 할 필요성이 있다. 도입된 PNG의 성분과 농도를 정확하게 측정해야 한다. 이에 따른 천연가스 내에 있는 미량 성분인 탄화수소류(C6-C10)의 정확한 측정이요구되어 표준가스의 개발이 필수적이다. 이 연구에서 개발한 일차 표준물질에 대한 조성과 농도는 10- 30 μmol/mol의 헥산, 헵탄, 옥탄, 노난, 데칸이며 바탕가스는 메탄이다. 탄화수소류(C6-C10)의 표준가스 제조는 각 성분 원료가스에 대한 순도분석이 완료된 가스를 ISO 6142에 근거하여 소급성이 있는 중량법으로 알루미늄 실린더에 제조하였다. 제조된 표준가스는 분석기로 표준가스간의 제조일치성, 실린더의흡착성, 안정성 변화 및 불확도 평가를 하였다. 결과는 알루미늄 실린더에서 내부표면의 흡착 손실이 적고 장기 안정성이 매우 우수하다는 것을 알 수 있었고, 헥산, 헵탄, 옥탄, 노난, 데칸의 농도 10-30 μmol/ mol 수준에서 불확도 0.79-1.63%이내의 표준가스를 개발하였다.
As the demand for natural gas increases with industrial development, the supply of natural gas is expected to become unstable with a shortage of imported natural gas. It is hence necessary to meet this demand by introducing and developing various types of natural gas, such as pipeline natural gas (PNG) and substituted natural gas (SNG), in addition to liquefied natural gas (LNG). The components included in PNG as well as their concentrations must be measured accurately, and a standard gas should be developed to accurately measure hydrocarbons (C6-C10), which are trace components included in natural gas. The components in the primary standard gas mixtures (PSMs) developed in the present study were hexane, heptane, octane, nonane, and decane with concentrations of 10-30 μmol/ mol with methane as the balance gas. Standard hydrocarbon (C6-C10) gas mixtures were prepared in aluminum cylinders by a gravimetric method with traceability following ISO 6142 with raw material gases, for which the purity of each component was analyzed completely. The prepared standard gas mixtures were analyzed by to evaluate the preparation consistency between the standard gas mixtures, the adsorbability of the cylinders, the variation of the stability, and the uncertainty. The results showed that aluminum cylinders have little adsorptive loss on their internal surfaces with excellent long-term stability. The developed standard gas mixture, containing hexane, heptane, octane, nonane, and decane with concentrations of 10-30 μmol/mol, showed an uncertainty in a range of 0.79 % - 1.63 %.
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