物理化學模型方面，本研究以雙膜理論（two-film theory）計算氣液相間之質量傳遞，以亨利定律描述界面相平衡並納入溫度修正。統御方程式上，將液滴群視為具代表性之集總系統（lumped system），以單一代表性液滴搭配液滴數目密度場，於一維軸向逆流假設下推導質量、動量與能量守恆方程式，並以四階 Runge–Kutta 法數值積分；復以現場量測之風量與進出口 CO₂ 濃度資料作為驗證基準，進而系統性分析設備設計與操作參數對吸收效能之影響。
透過適當調整代表液滴之粒徑 686 μm，模型預測之 CO₂ 質量吸收率與實測值 2.64 × 10⁻³ kg/s 相符；基於驗證後之模型，本研究針對液滴直徑、塔內氣速、液滴初始速度、塔高、進口 CO₂ 莫爾分率等五項參數進行分析。
結果顯示：質量吸收率與吸收效率對參數之響應方向未必一致，須併同檢視落下時間、單滴質量增量、質量吸收率與吸收效率四項指標，方能完整評估操作條件之優劣。液滴直徑於單滴尺度呈 U 形（最不利粒徑約 800 μm），惟系統級因數密度 nd∝ 1/d³ 主導，使 η 隨 d 由近 1.0 單調降至 0.006；塔內氣速增大使 ṁCO₂ 微升 9% 而 η 驟降 88%，呈產能與效率之背離；液滴初始速度與塔高則透過接觸時間直接主導，η 分別衰減 7.7 倍 (Vd(0) 增至 40 m/s）與遞增逾百倍（z₀ 增至 30 m）；進口 CO₂ 莫爾分率提高使 ṁCO₂ 躍升逾十倍而 η 持平（0.056 → 0.065）。

With respect to the physicochemical model, this study employs two-film theory to compute interphase gas–liquid mass transfer, and describes interfacial phase equilibrium via Henry's law with a temperature correction incorporated. For the governing equations, the droplet population is treated as a representative lumped system, in which a single representative droplet is coupled with a droplet number-density field; under a one-dimensional, axial, counter-current assumption, the conservation equations of mass, momentum, and energy are derived and integrated numerically using a fourth-order Runge–Kutta method. Field-measured air flow rates together with inlet and outlet CO₂ concentrations serve as the validation benchmark, upon which the influence of equipment design and operating parameters on absorption performance is systematically analyzed.
By appropriately tuning the representative droplet diameter to 686 μm, the model-predicted CO₂ mass absorption rate agrees with the measured value of 2.64 × 10⁻³ kg/s. Based on the validated model, five parameters are examined: droplet diameter, in-tower gas velocity, droplet initial velocity, tower height, and inlet CO₂ mole fraction.
The results show that the mass absorption rate and the absorption efficiency do not necessarily respond in the same direction to a given parameter; a complete assessment of the merits of an operating condition therefore requires the four indicators—fall time, per-droplet mass increment, mass absorption rate, and absorption efficiency—to be examined jointly. At the single-droplet scale, droplet diameter exhibits a U-shaped response (with the least favorable diameter at approximately 800 μm); however, at the system level the number density (∝ 1/d³) dominates, causing η to decrease monotonically from nearly 1.0 to 0.006 as d increases. Increasing the in-tower gas velocity raises ṁ by 9% while η drops sharply by 88%, reflecting a divergence between throughput and efficiency. The droplet initial velocity and the tower height govern performance directly through contact time, with η decreasing by a factor of 7.7 (as the initial velocity increases to 40 m/s) and increasing by more than a hundredfold (as z₀ increases to 30 m), respectively. Raising the inlet CO₂ mole fraction causes ṁCO₂to increase by more than tenfold while η remains essentially flat (0.056 → 0.065).

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