Cooling via air-water circuit

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We have a 6500 air separation unit in Shantou; no process design was carried out when the unit was installed, and the process from a 7500 unit in Tangshan at that time was used instead. The equipment configuration is based on the 7500 model, and the environmental temperature conditions are set according to those in Tangshan. The air separation equipment has been operating stably. The problem now is that since the onset of summer, the temperature of the water supply has been rising steadily. In the past, after being cooled by the cooling tower, the temperature of the water supply remained between 22 and 25 degrees; currently, it ranges from 29.5 to 35 degrees. The entire system is currently running at too high a temperature; the air compressor operates unstably, and the exhaust temperatures of the second and third stages of the oxygen and nitrogen compressors are between 170–175 degrees, with pressures of 89–94 – which is quite problematic. Additionally, no space was reserved for a second cooling tower during the design phase, so adding another cooling tower is not practical. It was also tried to draw pipes from under the plate heat exchanger to directly introduce the contaminated nitrogen gas into the water inlet tank, but the result was unsatisfactory. The options being considered now are: 1. Purchase ice and add it to the tank to lower the temperature (this is already being done); if no ice is added now, the temperature will continue to rise (it seems this situation can’t go on forever). 2. Install an ice maker in the water circuit to reduce the temperature of the water entering the tank. (Budget parking requires 3 days.) I hope experts can come up with a better solution that ensures the equipment doesn’t have to stop operating, or that the downtime is no more than 24 hours.