O2/H2O气氛下CH4燃烧特性与置换天然气水合物联产方案

对O2/N2, O2/CO2和O2/H2O三种气氛下CH4燃烧特性及主要污染物生成进行了数值模拟，将出口O2浓度作为污染物排放的协同考虑因素，提出了基于O2/H2O气氛燃烧置换天然气水合物的新技术方案，比较了3种燃烧气氛对甲烷燃烧温度、燃烧速率、污染物(NOx和碳黑)生成量及燃烧效率等的影响. 结果表明，相较于O2/N2和O2/CO2气氛，O2/H2O气氛下燃烧温度最低、燃烧速率最高、污染物生成量最少、燃烧效率最高、出口O2浓度最低. 确定了与传统燃烧温度分布特征曲线相匹配的浓度配比为32vol% O2/68vol% H2O. 基于模拟研究结果，提出了一套O2/H2O燃烧技术与开发天然气水合物联产的技术新思路.

Combustion characteristics of CH4 at O2/H2O atmosphere and gas hydrate co-production process

Based on the improvement of O2/CO2 combustion technology, O2/H2O (oxy?steam) combustion technology has been widely concerned by scholars at home and abroad. Because of its advantages of small system coupling, easy start-up and low concentration of pollutants, it may become the next generation potential oxygen-rich combustion technology. At present, most studies have studied the effect of N2, CO2, and H2O(g) as diluents on the combustion characteristics of methane in single or pairwise comparisons. However, the combustion characteristics of methane in O2/N2, O2/CO2 and O2/H2O atmospheres are rarely analyzed comprehensively. And there are few researches on related applications of O2/H2O combustion technology at home and abroad. In this paper, the combustion characteristics of CH4 and the generation of main pollutants under the three atmospheres of O2/N2, O2/CO2 and O2/H2O were studied. Based on this, a new technology case based on O2/H2O atmosphere combustion and replacement of natural gas hydrates was proposed. The effects of three combustion atmospheres on combustion temperature, combustion rate, generation of pollutants (NOx, Soot), and combustion efficiency of methane were compared and analyzed. Simultaneously, the size of the outlet O2 concentration was taken as a synergistic consideration for pollutant emissions. The results showed that compared with O2/N2 and O2/CO2 atmospheres, the combustion temperature was the lowest, the combustion rate was the highest, the generation of pollutants (NOx, Soot) was the least, the combustion efficiency was the highest, and the export O2 concentration was the lowest under the atmosphere of O2/H2O. Therefore, O2/H2O combustion technology stood out. On this basis, the concentration ratio of O2/H2O matching with the characteristic curve of traditional combustion temperature distribution was determined: 32%O2/68%H2O. Based on the results of the simulation study, a new set of O2/H2O combustion technology and the development of natural gas hydrates co-production process was proposed, which can provide theoretical and technical support for future industrial applications of advanced combustion technology.