Simulation-based optimization of cycle timing for CO2 capture and hydrogenation with dual function catalyst
Simulation-based optimization of cycle timing for CO2 capture and hydrogenation with dual function catalyst
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DOI：
10.1016/j.cattod.2021.08.023
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发表时间：
2022-06-07
期刊：
影响因子：
5.3
通讯作者：
Gonzalez-Velasco, Close Juan R.
中科院分区：
文献类型：
--
作者：
Bermejo-Lopez, Alejandro;Pereda-Ayo, Benat;Gonzalez-Velasco, Close Juan R.
CO2甲烷化在未来能源系统中将发挥重要作用。多余的可再生电能可以转化为可储存的甲烷，以在需要时平衡能源需求。此外，CO2甲烷化可以在CO2储存和还原的交替步骤中进行，避免了昂贵的CO2纯化步骤。在这项工作中，我们将使用先前开发和验证的模型，通过模拟优化CO2吸附和加氢循环时间（t（CO2）/t（H2））。催化剂的性能通过CO2转化率（X-CO2，%）、H-2转化率（X-H2，%）和CH 4产量（Y-CH 4，mmol g（-1）循环（-1））来量化。长的吸附和加氢时间导致每个循环的高CH 4产量，然而，低CO2和H-2转化率。因此，接近催化剂饱和的吸附时间（t（CO2）=60 s）和适度的氢化时间是优选的。为了更好地选择最佳加氢时间，设定了一个新的催化参数，即CH 4的平均生成速率（rCH（4），μ mol g（-1）s（-1））。最佳加氢时间为120 s。除了具有高的CH 4平均形成速率之外，t（CO2）/t（H2）= 60/120的循环定时将允许用三个相同的床并联工作，一个在吸附模式下，两个在再生模式下。在60/120的最佳循环时间下，CH 4的产生导致148 μ mol g（-1）循环（-1）（1.2 μ mol CH 4 g（-1）s（-1）），CO2和H-2转化率分别为25%和43%
CO2 methanation could play a significant role in the future energy system. The excess of renewable electric energy can be transformed into storable methane to balance the energy demand when required. Moreover, the CO2 methanation can be performed alternating steps of CO2 storage and reduction, avoiding expensive CO2 purification steps. In this work, we will use a previously developed and validated model to optimize by simulation the CO2 adsorption and hydrogenation cycles timing (t(CO2)/t(H2)). The performance of the catalyst is quantified by the CO2 conversion (X-CO2, %), H-2 conversion (X-H2, %) and CH4 production (Y-CH4, mmol g(-1) cycle(-1)). Long adsorption and hydrogenation times result in high CH4 productions per cycle, however, low CO2 and H-2 conversion. Therefore, adsorption times close to the catalyst saturation (t(CO2)=60 s) and moderate hydrogenation times are preferable. To better select the optimal hydrogenation time, a new catalytic parameter is set, the average formation rate of CH4 (rCH(4), mu mol g(-1) s(-1)). The optimal hydrogenation time is set at 120 s. In addition to having a high average formation rate of CH4, t(CO2)/t(H2)= 60/120 cycle timing would allow to work with three identical beds in parallel, one in adsorption mode and two in regenerating mode. With the optimum cycle timing of 60/120 the production of CH4 results in 148 mu mol g(-1) cycle(-1) (1.2 mu mol CH4 g(-1) s(-1)) and a CO2 and H-2 conversion of 25% and 43%, respectively