The exhaust pressure of a refrigeration unit is high in summer; how can secondary condensation be used to reduce energy consumption?

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Currently, a 60P screw chiller is in use, operating with R507 as the refrigerant. The cooling water uses a closed-loop cooling system; during summer, the temperature of this water is around 32–35°C, while the exhaust pressure is 17–19 bar. Due to this high exhaust pressure, energy consumption is also high. There is low-temperature carbon dioxide available on site, which can exist in gaseous form, liquid form, or as a mixture of both, at temperatures ranging from -10°C to -20°C. This carbon dioxide is not supplied continuously, and its amount is not always sufficient to meet the cooling needs of the chiller. Now, it is planned to use the circulating water to condense the gas once first, and then utilize that energy to carry out a second stage of condensation in order to reduce the exhaust pressure. The temperature of carbon dioxide is too low and the pressure is too high, so it cannot be cooled directly by circulating water; the heat exchanger was damaged by freezing in the past. Please give me some advice