直接空气捕集内热源式反应器的动态仿真研究

Dynamic simulation study of direct air capture reactor with internal heat source

《巴黎协定》的签订和"双碳"目标的制定对中国的碳排放提出更严格的要求,CO_(2)直接空气捕集技术(DAC)是一种很有潜力的碳负排放技术。对吸附式DAC技术的核心部件做出改进,类比吸附制冷领域的除湿换热器结构,提出设置内热源的反应器,并对其进行模型研究。通过计算获得温度和吸附量参数的时间和空间分布,在环境温度为25℃、冷热源温度分别为15℃和80℃时,第7个循环进入稳定阶段。随着循环的进行,温度跟随换热流体温度快速响应,呈现交替的高低值,吸附量表现为锯齿状的上升趋势;空间分布上,吸附和解吸结束时反应器内各位置的温度差不超过10℃,单层内最大温差在1℃左右,吸附量差值小于0.01 mmol/g(第4层),反应器内吸附剂均匀发挥作用。总体表现出均匀高效的传热传质性能,可以根据需要结合不同吸附剂和流体介质应用于各类DAC场景。

The signing of the Paris Agreement and the establishment of Carbon Peaking and Carbon Neutrality goals have put forward stricter requirements for China's carbon emissions.CO_(2)direct air capture technology(DAC)is a promising carbon negative emission technology.Analogous to the dehumidification heat exchanger structure in the field of adsorption refrigeration,improvements have been made to the core components of adsorption DAC technology.Propose a reactor with an internal heat source and conduct model research on it.Obtain the time and spatial distribution of temperature and adsorption parameters through calculation.When the ambient temperature is 25℃and the temperature of the cold and heat sources is 15℃and 80℃respectively,the seventh cycle enters the stable stage.As the cycle progresses,the temperature rapidly responds to the temperature of the heat transfer fluid,exhibiting alternating high and low values.The adsorption capacity shows a serrated upward trend.In terms of spatial distribution,the temperature difference at each position inside the reactor at the end of adsorption and desorption shall not exceed 10℃.The maximum temperature difference within a single layer is around 1℃(4th layer).The difference in adsorption was less than 0.01 mmol/g(4th layer),the adsorbent functioned uniformly in the reactor.Overall,it exhibits uniform and efficient heat and mass transfer performance,which can be combined with different adsorbents and fluid media as needed for various DAC scenarios.