Capturing CO2 from ambient air using a polyethyleneimine–silica adsorbent in fluidized beds
Capturing CO2 from ambient air using a polyethyleneimine–silica adsorbent in fluidized beds
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DOI：
10.1016/j.ces.2014.05.018
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发表时间：
2014-09
影响因子：
4.7
通讯作者：
Wen-Bo Zhang;Hao Liu;Cheng-gong Sun;T. Drage;C. Snape
中科院分区：
文献类型：
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作者：
Wen-Bo Zhang;Hao Liu;Cheng-gong Sun;T. Drage;C. Snape
碳捕集与封存（CCS）采用多种技术组合来捕获、运输和储存来自大型点源（如燃煤或天然气发电厂）的二氧化碳（CO2）排放。从环境空气中捕获二氧化碳一直被认为是一种碳负技术，可以减少空气中人为的二氧化碳排放。在实验室规模的鼓泡流化床（BFB）反应器中，研究了介孔二氧化硅负载的聚乙烯亚胺(PEI) -二氧化硅吸附剂对环境空气中co2的捕集性能。空气捕获试验持续了4至14天，在BFB反应器中使用1千克pei -二氧化硅吸附剂。尽管环境空气中的二氧化碳浓度较低，但在相对较短的7.5 s气固接触时间内，实现了接近100%的二氧化碳捕获效率。空气捕获的平衡co2吸附容量高达7.3%，这是迄今为止报道的最高值之一。完成了概念设计，以评估使用pei -二氧化硅吸附剂从环境空气中捕获二氧化碳的技术和经济可行性，每年捕获1 mt - co2。提出的新型“PEI-CFB空气捕集系统”主要由循环流化床（CFB）吸附器和BFB解吸器组成，co2捕集能力为40 t-CO2/d。驱动空气通过CFB吸附剂需要很大的压降，同时也需要在循环中悬浮和循环固体吸附剂，这导致比其他空气捕获系统更高的电力需求。然而，采用变温吸附（TSA）技术的再生策略，在单独的BFB解吸器导致了更小的热能需求。所需总能量为6.6 GJ/t- co2，与其他参考空气捕获系统相当。通过预测未来大型点能源的脱碳主要通过整合CCS技术来实现，该情景下的运营成本估计为108美元/吨二氧化碳捕获，152美元/吨二氧化碳避免率为0.71。对提议的40 t-CO2/天“PEI-CFB空气捕获系统”的进一步研究仍然需要，其中应该包括资本成本的评估和使用pei -二氧化硅吸附剂的实验室规模的CFB系统进行空气捕获的实验研究。
Carbon Capture and Storage (CCS) uses a combination of technologies to capture, transport and store carbon dioxide (CO2) emissions from large point sources such as coal or natural gas-fired power plants. Capturing CO2from ambient air has been considered as a carbon-negative technology to mitigate anthropogenic CO2emissions in the air. The performance of a mesoporous silica-supported polyethyleneimine (PEI)–silica adsorbent for CO2capture from ambient air has been evaluated in a laboratory-scale Bubbling Fluidized Bed (BFB) reactor. The air capture tests lasted for between 4 and 14 days using 1 kg of the PEI–silica adsorbent in the BFB reactor. Despite the low CO2concentration in ambient air, nearly 100% CO2capture efficiency has been achieved with a relatively short gas–solid contact time of 7.5 s. The equilibrium CO2adsorption capacity for air capture was found to be as high as 7.3 wt%, which is amongst the highest values reported to date. A conceptual design is completed to evaluate the technological and economic feasibility of using PEI–silica adsorbent to capture CO2from ambient air at a large scale of capturing 1 Mt-CO2per year. The proposed novel “PEI-CFB air capture system” mainly comprises a Circulating Fluidized Bed (CFB) adsorber and a BFB desorber with a CO2capture capacity of 40 t-CO2/day. Large pressure drop is required to drive the air through the CFB adsorber and also to suspend and circulate the solid adsorbents within the loop, resulting in higher electricity demand than other reported air capture systems. However, the Temperature Swing Adsorption (TSA) technology adopted for the regeneration strategy in the separate BFB desorber has resulted in much smaller thermal energy requirement. The total energy required is 6.6 GJ/t-CO2which is comparable to other reference air capture systems. By projecting a future scenario where decarbonization of large point energy sources has been largely implemented by integration of CCS technologies, the operating cost under this scenario is estimated to be $108/t-CO2captured and $152/t-CO2avoided with an avoided fraction of 0.71. Further research on the proposed 40 t-CO2/day ‘PEI-CFB Air Capture System’ is still needed which should include the evaluation of the capital costs and the experimental investigation of air capture using a laboratory-scale CFB system with the PEI–silica adsorbent.