Abstract As demand for natural gas increases, it is important to understand its life cycle emission intensity. A framework is developed for performing bottom-up greenhouse gas (GHG) life cycle assessment of natural gas transmission pipelines to assist project environmental assessments. Three large-scale pipelines in Canada were examined: Alliance mainline (50 million m3/d, 3000 km), Prince Rupert phase 1 (PR1, 57 million m3/d, 878 km), and Prince Rupert phase 2 (PR2, 102 million m3/d, 878 km). Fundamental engineering principles are used for calculation accuracy, with a sensitivity analysis to identify key parameters. The model boundary includes pipeline construction, operation, and decommissioning. The resulting transportation GHG emission intensities are 1.49, 0.77, and 1.78 gCO2eq/GJ.km for the Alliance, PR1, and PR2 projects, respectively. The operating phase represents 78%–95% of the overall emissions. Operating at higher pressures could reduce emission intensity by up to 49% by increasing flow efficiency. The research provides a user-friendly open-source template that can be used to examine alternative scenarios.

中文翻译：

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为天然气输送管道制定温室气体生命周期评估框架

摘要 随着对天然气需求的增加，了解其生命周期排放强度非常重要。开发了一个框架，用于对天然气输送管道进行自下而上的温室气体 (GHG) 生命周期评估，以协助项目环境评估。考察了加拿大的三条大型管道：Alliance 干线（5000 万立方米/天，3000 公里）、鲁珀特王子港一期（PR1，5700 万立方米/天，878 公里）和鲁珀特王子港二期（PR2，1.02 亿公里）立方米/天，878 公里）。基本工程原理用于计算精度，并通过敏感性分析来确定关键参数。模型边界包括管道建设、运行和退役。对于 Alliance、PR1 和 PR2 项目，由此产生的交通温室气体排放强度分别为 1.49、0.77 和 1.78 gCO2eq/GJ.km。运行阶段占总排放量的 78%–95%。通过提高流动效率，在更高压力下运行可以将排放强度降低多达 49%。该研究提供了一个用户友好的开源模板，可用于检查替代方案。