天然气生产企业碳排放核算与预测方法研究--以四川盆地天然气开发为例

Methods to calculate and predict carbon emission in natural-gas enterprises:An example from the development of natural gas in Sichuan Basin

碳中和已成全球共识,世界能源体系正加速向低碳化演变。中国能源发展进入新时代,“双碳”目标成为经济社会发展根本遵循,作为碳排放主要来源的能源行业正大力实施绿色低碳发展战略,但要实现“双碳”目标,需建立统一规范的碳排放统计核算体系,并对碳排放量进行科学预测。选取天然气生产企业的碳排放核算及预测方法作为研究对象,基于天然气生产企业作业链,系统性梳理出天然气勘探、开发、处理、输送各环节的碳排放特征,并归类为化石燃料燃烧排放、火炬系统燃烧排放、工艺放空排放、电力消耗隐含排放等四大碳排放源,建立起碳排放核算与预测方法。通过选取四川盆地典型的常规气、页岩气、高含硫气藏进行实例测算与分析,研究结果表明:①鉴于不同类型气藏生产的碳排放结构和强度存在较大差异,为保证核算和预测结果的可靠性,对于涉及到多种类型气藏开发的企业,在碳排放核算和预测时要分类进行,并加强基础数据的统计与监测;②在能耗双控向碳排放双控转变的大趋势下,为促进油气行业的高质量发展,在建立碳排放双控指标时,应以碳排放强度指标为核心,以碳排放总量指标为辅,针对不同类型的气藏、建立不同的碳排放强度动态标准;③天然气生产企业既是甲烷的主要生产供应者、也是甲烷排放者,应加强对甲烷减排控排措施的研究。结论认为,该研究成果可以为天然气行业建立更为科学合理的碳排放核算与预测方法体系提供参考和借鉴。

Carbon neutrality has now become global consensus and the world is accelerating its energy structure developing into low carbonization.China's energy evolution has gotten into a new era,and the"dual-carbon"goal is proved to be the fundamental compliance in economic and social growth.Energy industry,as the main carbon-emission source,strives to implement a green and low-carbon strategy.However,to attain this goal,it is essential to setup a uniform and standard system for emission calculation and scientific prediction.So,some calculation and prediction methods in natural-gas enterprises were taken as objectives.Based on entire production chain in these enterprises,carbon-emission characteristics from natural-gas exploration,development,treatment to transmission were fully made clear.Four major sources were categorized,including emission from fossil fuel combustion,flare combustion,process venting and hidden power consumption.Moreover,both calculation and prediction methods were created,which have been applied to conventional gas,shale gas,and high sulfur gas reservoirs in Sichuan Basin.Results show that(i)considering great difference between emission intensity and structure in various reservoir development,emission calculation and prediction should be classified,especially for those enterprises involving with multiple reservoir development,to ensure the reliability of calculation and prediction results.Meanwhile,basic data statistics and monitoring should be strengthen;(ii)under such dual-control transition from energy consumption to carbon emission,one indicator of emission intensity should be the core and supplemented by the other of emission when establishing emission dual-control indicators in order to promote petroleum industrial growth with high quality,and different standards on the intensity should be established for each type of gas reservoirs;and(iii)gas enterprises,as not only the main methane producers but emitters,should expand their researches on methane's emission reduction and make countermeasures.It is concluded that the results may provide references for the natural-gas industry to establish more scientific and reasonable carbon-emission calculation and prediction methods.