Why can’t the temperature of the off-gas outlet device on the wastewater stripping side line be reduced?

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We employ a single-tower pressurized side-stream extraction process. The side-stream gas is extracted from the outlet on the main stripping tower, and after undergoing three stages of condensation (the first stage involves cooling through heat exchange with raw water, the second stage uses circulating water for cooling, and the third stage also employs circulating water for cooling), as well as three stages of fractional distillation, it is sent to the sulfur treatment unit and incinerated in an incinerator. The first, second, and third stage separation liquids exchange heat with the feed water in the separation liquid cooler, are cooled by circulating water, and finally return to the feed water tank. Problems that occurred during this startup: 1. After the startup, there was no liquid level in the primary condenser (where there used to be one), and there was also no liquid level in the secondary and tertiary coolers (as there hadn’t been any previously), which resulted in the crude ammonia gas containing liquid. 2. The temperature drop in the side line passing through the first, second, and third fractionators does not decrease; it remains above 150 degrees. 3. Circulating water was introduced into the secondary and tertiary fractionation coolers (it was not used before; it is now added due to the high temperatures). The temperature at the inlet of the secondary fractionation cooler can be raised to 90 degrees, while the temperature at the outlet rises to 130 degrees. The inlet temperature of the third-stage separator is 130 degrees, while the outlet temperature is 140 degrees. Circulating water is used in the third-stage separator coolant to reduce the temperature to 100 degrees. The liquid level in the third-stage separator does not decrease; what can be done is to open a few valves on the secondary to tertiary bypass lines in order to increase the pressure and thus lower the liquid level, but this causes the temperature to rise again. 4. When circulating water is introduced into the secondary and tertiary fractional condensate coolers, salt deposition tends to occur in the shell side, leading to blockages in the equipment pipelines. Everyone discussed how to control the device temperature, pressures at various stages, and the issue of salt deposition and blockages in the pipelines. Please, experts, give me some advice!