Cooling tower make-up water and wastewater discharge

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A certain enterprise is equipped with a circulating cooling water system. The designed circulating water volume Qr for the project’s cooling tower is 500 m3/h. The system is an open cooling system. Based on the calculations, the water consumption and discharge volumes for this project are as follows: In accordance with the \"Design Code for Industrial Circulating Cooling Water Treatment\" (GB 50050-2017), the formula for calculating the evaporation volume Qe of a cooling tower is as follows: Qe = k × Δt × Qr, where k is the temperature coefficient (1/°C), with a value of 0.0014 ； Δt —— Temperature difference between the inlet and outlet water of the cooling tower (°C); take 10℃ ； Qr——Circulating water volume (m3/h), take 500 m3/h ； Then Qe=0.0014×10×500=7 (m3/h). The wind-induced water loss Qw is taken as 0.1% of Qr, namely 0.5 m3/h. The total amount of water lost through evaporation and wind erosion, Qe+Qw, is 7+0.5=7.5 m3/h, which is equivalent to 180 m3/day and 59,400 m3/year. For the project, the concentration factor of the cooling tower is set at 3. The fresh water supply volume to the cooling tower is Qm = Qe × N / (N – 1) = 7 × 3 / (3 – 1) = 10.5 m3/h, which is equivalent to 252 m3/day and 83,160 m3/year. The wastewater discharge volume of the cooling tower is Qb = Qm – Qe – Qw = 10.5 – 7 – 0.5 = 3 m3/h, which is equivalent to 72 m3/day and 23,760 m3/year. The total water consumption of the cooling tower is 510.5 m3/h (12,252 m3/day), of which 10.5 m3/h (252 m3/day) is fresh water, and 500 m3/h (12,000 m3/day) is recycled water; the recycling rate of water is 97.94%. Through calculations, it was found that the largest amount of wastewater generated by the enterprise comes from the circulating cooling water system; the wastewater discharge volume from the cooling tower is Qb = 72 m3/day, or 23,760 m3 per year. The environmental protection authorities require that this water be treated at the plant’s wastewater treatment facility. Is this requirement reasonable? Additionally, the largest flow of wastewater in the entire plant comes from the subcooling system; is this indeed the case for this cooling system? I would appreciate it if some experts could help provide some advice and analysis. Please!