煤基合成气制甲烷工艺与催化剂研究进展

煤制天然气是煤炭高效清洁利用的重要途径,甲烷化是煤制天然气的关键反应,具有强放热、可逆和体积缩小的特点。针对甲烷化反应特点,工艺上主要采用多段绝热循环稀释CO含量、合成气变换与净化等策略实现高甲烷收率。对现有的传统甲烷化工艺进行归纳总结,并分析各自甲烷化工艺的特点。在此基础上,对甲烷化工艺路线进行比较,提出开发煤制天然气耐硫甲烷化新工艺,并对该工艺进行探讨。常规钼基耐硫甲烷化催化剂由于原料空速和转化率低,水热稳定性也有待提高,因而开发粗煤气多段耐硫甲烷化制天然气节能工艺及高效耐硫甲烷化催化剂是今后的研究方向。

Advance in methanation processes and catalysts for synthetic natural gas from coal

The production of synthetic natural gas (SNG) is an important route of the highly efficient and clean utilization of coal.The key reaction of coal to SNG is methanation,which is strong exothermic, reversible and reduced volume after the reaction.In order to get high methane yield,the measures of multistage adiabatic cycle to dilute CO and shift/purification of syngas was adopted.The existing traditional process of methanation and their characteristics were summarized.On this basis,the methanation processes were compared,and the development of novel sulfur tolerant methanation for coal to SNG was proposed.The advance in Ni based and Mo based catalysts for methanation were reviewed. the existing problems of the process and catalysts of methanation was analyzed,Due to low space velocity and low conversion of conventional Mo based sulfur tolerant methanation catalyst, which hydrothermal stability needs to be improved,the future research trend of coal to SNG is the development of multistage sulfur tolerant methanation processes and the corresponding high performance catalysts.