基于能量分析的天然气新型利用方式研究

Research on New Utilization of Natural Gas based on Energy Analysis

针对天然气燃烧产生温室气体,能源利用率不高等问题,提出了天然气的新型利用方式,即将超临界水氧化技术引入到天然气能量利用中,可以大幅提高燃烧效率。此外,从能量释放层面比较了间接氧化与直接氧化反应内部火用损失,揭示了超临界水间接氧化的反应机理。最后比较了天然气超临界水氧化反应器和实际燃气锅炉的热效率、火用效率。结果表明,间接氧化这新型燃烧方式可以将天然气的化学能品位从1降为0.80,实现了能量的梯级释放。与直接氧化相比,间接氧化的火用损失减少约4.6%。根据能量分析和火用分析,该新型燃烧方式的热效率,火用效率相比传统燃气锅炉分别提高13%和19.5%。

In view of the problems of greenhouse gases produced by natural gas combustion and low energy utilization efficiency,a new utilization of natural gas is put forward.Supercritical water oxidation technology is applied into energy utilization of natural gas,it can greatly improve combustion efficiency.In addition,the internal exergy loss of indirect oxidation was compared with that of direct oxidation at the level of energy release,and the reaction mechanism of indirect oxidation in supercritical water was revealed.Finally,thermal and exergy efficiency of natural gas supercritical water oxidation reactor and actual gas-boiler are compared.The results show that indirect oxidation can reduce chemical energy grade of natural gas from 1 to 0.80,and realize cascade energy release.Compared with direct oxidation,exergy loss of indirect oxidation is reduced by about 4.6%.According to energy and exergy analysis,thermal and exergy efficiency of this new combustion are increased by 13%and 19.5%respectively compared with the traditional gas fired boilers.