Problems encountered with the exhaust gas absorption tower on the tank top

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The methanol tanks in the tank farm are designed to absorb methanol from exhaled breath. Due to the extreme instability of the exhaled air, the flow rate is 0 most of the time, but it can reach over 1,000 cubic meters per hour at its highest levels. When there is discharge, the flow rate is generally much lower than the maximum flow rate. During design, it is of course necessary to design for the maximum gas volume. According to Aspen calculations, at the maximum gas flow rate, the minimum required liquid flow rate is less than 1000 kg/h. If a packed tower is used for absorption, then to maintain a minimum spraying density, about 10 tons of water per hour are needed. To reduce the water volume, part of the liquid phase at the bottom of the tower is recycled to the top of the tower; however, the methanol concentration in the gas exiting from the top of the tower **increases**, failing to meet the emission requirements. With a plate tower, the pressure drop in the tower fails to meet the requirements for operating at atmospheric pressure. Moreover, due to unstable exhaled breath, leakage occurs most of the time. Do any of you have any good suggestions? Thank you!