CO2 capture from lime kiln using AMP-DA2MP amine solvent blend: A pilot plant study

Abstract

This experimental study covered pilot plant analysis of novel AMP and 1,5–diamino–2–methylpentane (DA2MP) amine solvent blend for CO2 capture from a lime kiln. The gas flow rate (F(GAS)), amine solution flow rate (F(amine)), CO2 concentration and reboiler temperature (T(REB)) were kept at 14 SLPM, 50 mL/min, 30 vol.% CO2 (N2 balance) and 120 °C respectively. The AMP concentration was kept at 2 kmol/m3 while DA2MP was varied from 1.5 kmol/m3 to 2 kmol/m3. The MEA and AMP-DA2MP comparative analysis was based on rich amine loading (αrich, mol CO2/mol amine), lean amine loading (αlean, mol CO2/mol amine), cyclic loading (CL, mol CO2/mol amine), cyclic capacity (CC, mol CO2/L–amine soln.), CO2 absorption rate (rabs, g–CO2/hr), CO2 absorption efficiency (%), regeneration energy (Qreg, GJ/tonne CO2), absorber overall average volumetric mass transfer coefficient (KGav(ave), kmol/kPa.hr. m3), desorber mass transfer coefficient (KLav, hr–1), initial amine solution utilized (Aminesoln._utilized, g-amine soln./g-CO2) and initial amine solution cost (US$/g-CO2). The influence of sensible energy (Qsen, GJ/tonne CO2), vaporization energy (Qvap, GJ/tonne CO2), and desorption heat (ΔHdes, GJ/tonne CO2) towards regeneration energy (Qreg) was also examined. Results showed that the AMP-DA2MP blend possesses higher CO2 absorption efficiency (up to 36.17%), higher KGav(ave) (up to 65.85%), higher KLav (up to 28.29%) and lower Qreg (up to 32.54%) compared to the single solvent MEA. Also, MEA possessed higher initial amine solution utilized (28.86%) and lower initial amine solution cost (28.5%) compared to the AMP-DA2MP blend. This is an initial revelation that AMP-DA2MP can provide cost-effective CO2 capture from a lime kiln.