Seeking assistance regarding deviations in the design and operation of amine-based desulfurization

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There is currently a natural gas purification plant that uses an amine-based purification process; there is a significant discrepancy between the design specifications and the actual operating parameters. I would be extremely grateful if Lord Haichuan could help analyze the reasons for this. Below is a comparison of the design parameters and the actual operating parameters: Design parameters for the absorption tower: Operating pressure: 4 MPa; Operating temperature: 40°C; Designed treatment capacity: 23,000 Nm3/h; Amine solution flow rate: 50 m3/h, with a concentration of 43%; Type of packing: BX500 structured packing; Packing height: 12 m (2 sections); Diameter of the absorption tower: 1.3 m. Design specifications for the purified gas: CO2 content not exceeding 3%, H2S content not exceeding 4 ppm. Components of the feed gas: Component | Molecular content Methane 0.8528 Ethane 0.0003 Propane 0.0001 n-Butane 0.0001 i-Butane 0.0001 n-Pentane 0.0001 i-Pentane 0.0001 n-Hexane 0.0000 n-Heptane 0.0000 n-Octane 0.0000 n-Nonane 0.0000 n-Decane 0.0000 H2O 0.0000 H2S 0.0108 CO2 0.0800 Nitrogen 0.0554 MDEAmine 0.0000 Oxygen 0.0001 Actual operating parameters: Operating pressure: 3 MPa Operating temperature: 30°C Processing capacity: 12,500 Nm3/h Amine solution circulation volume: 43 m3/h, with a concentration of 43% Outlet specifications for the purified gas: CO2 content of 0.5%, H2S content of 50 PPM Actual components of the feed gas: Component | Molecular fraction % Component | Molecular fraction % Hydrogen (H2) 0.0437 Methyl ethyl sulfide (CH3SC2H5) 2.74×10-6 Helium (He) 0.0345 Methyl mercaptan (CH3SH) 2.22×10-5 Nitrogen (N2) 1.09 Ethyl mercaptan (C2H5SH) 5.04×10-3 Carbon dioxide (CO2) 5.34 Dimethyl sulfide (CH3SCH3) 8.08×10-7 Methane (CH4) 93.08 Ethyl sulfide (C2H5SC2H5) Not detected Ethane (C2H6) 0.0328 Carbon disulfide (CS2) 1.61×10-5 Propane (C3H8)