Partial condensation for maleic anhydride recovery?

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The waste gas recovery system for the maleic anhydride storage tank utilizes a partial condensation process and capture devices; since maleic anhydride has a boiling point of 202°C at atmospheric pressure, it is not possible to cool the gas temperature too low, in order to avoid blockages in the pipes and equipment due to the crystallization of liquid maleic anhydride. Therefore, it was decided to cool the gas to 54 °C, which is slightly above the crystallization point of maleic anhydride at 52.8 °C. At 54 °C, the vapor pressures of water and maleic anhydride are 15.5 KPa and 0.36 KPa respectively; when the gas is cooled to 54 °C, the water remains uncooled, while the maleic anhydride gas condenses in part within the condenser. Why is it necessary for this gas to enter a maleic anhydride trap where it is absorbed by water before being recovered in the recovery tank?