Does the zero discharge of heavy metal wastewater need to control the discharge concentration?

Generally, the last process of zero wastewater discharge is evaporation. The evaporation process can be divided into single effect, second effect, third effect, fourth effect, fifth effect, MVR and so on. Their investment costs are rising. Although the latter recovers energy, the high price of steam leads to the amazing operating cost of the evaporator. Since evaporation is a necessary process of zero emission, is there any way to reduce the amount of water entering the evaporator? If the water inflow is less, the investment and operation costs will of course be lower. Of course there is! DTRO membrane is used to further concentrate the waste water that needs evaporation, so as to reduce the amount of waste water, thus achieving the purpose of reducing investment costs and operating costs. Zheng Jin environmental protection has many successful cases in reducing wastewater before zero-emission evaporation. The total investment cost of zero emission has dropped a lot.