Abstract

A comprehensive 2-D transient heat and mass transfer analysis is carried out to identify the best reactor configuration in terms of better charge and discharge characteristics for a CO₂-activated carbon (Maxsorb III)-based sorption systems. Reactors with different aspect ratios (AR) ranging from 0.35 to 7.8 are analysed for a wide range of convective heat transfer coefficient (h), constant pressure charging, and discharging cases. Effects of external cooling/heating fluid temperature, convective heat transfer coefficient (h), operating pressures are studied for both the charging (1–100 bar) and discharging (65–110 bar) cases. The adsorption cell with AR= 7.8 showed the best performance for CO₂ adsorption/desorption in a fixed charge/discharge time of 300 s. For charging at 100 bar pressure, the reactor with AR= 7.8 resulted in an increment of 23.34% in CO₂ uptake and reduction in maximum bed temperature by 27 K compared to that of the reactor with AR = 0.35. For h = 700 and 500 W/m² K, the reactor with AR = 7.8 adsorbs 1300 g and desorbs 832 g of CO₂/kg of adsorbent at 100 bar and 65 bar for external cooling and heating fluid temperature of 293 K and 800 K, respectively. The study concludes that better discharge performance can be attained by proper selection of AR even at a lower heating fluid temperature as the reactor with AR = 7.8 at 600 K can desorb 46 to 131 g of extra CO₂ w.r.t. all ARs at 800 K. The proposed reactor configurations are supposed to play a vital role in designing of adsorption-based green refrigeration and carbon capture systems.

Graphic abstract

中文翻译：

---

几何和传热参数对CO 2活性炭对吸附-解吸特性的影响

摘要

进行了全面的二维瞬态传热和传质分析，以根据基于CO ₂活性炭（Maxsorb III）的吸附系统更好的充放电特性，确定最佳的反应器配置。分析了宽高比（AR）在0.35到7.8之间的反应堆，以分析大范围的对流传热系数（h），恒压装料和卸料情况。研究了外部冷却/加热流体温度，对流传热系数（h），工作压力对充气（1-100 bar）和排气（65-110 bar）情况的影响。AR = 7.8的吸附池显示出最佳的CO ₂性能在300 s的固定充电/放电时间内进行吸附/解吸。对于在100 bar压力下的进料，与AR = 0.35的反应器相比，AR = 7.8的反应器导致CO ₂吸收增加23.34％，最大床温降低27K。对于h  = 700和500 W / m ² K，AR = 7.8的反应器在100 bar和65 bar下吸附1300 g并解吸832 g CO ₂ / kg吸附剂，以进行293 K和800的外部冷却和加热流体温度分别为K。该研究的结论是，更好的放电性能可通过AR的适当选择即使在较低的加热流体的温度为具有AR = 7.8反应器中，在600 K可脱附46131克额外CO，可实现₂ 所有AR都在800 K下运行。拟议的反应堆配置在设计基于吸附的绿色制冷和碳捕集系统中起着至关重要的作用。

图形摘要