Water pollution characteristics and whole process control technologies in preserved fruit industry

In terms of specific water pollution problem derived from the processing of preserved fruit in southern China, the origin and characteristics of the wastewater were analyzed, and a systematic study on the technical route, approaches and processes of water saving, waste utilization and wastewater treatment in the industry performed. From a perspective of cleaner production and based on a whole processing control technical route, i.e. “source water saving, intermediate pollutant control, end treatment”, a water saving technology using ultrasonic wave and water recycling was proposed for cleaning fruits and vegetables and desalination and rinse of fruit billet. From a perspective of circular economy, a comprehensive utilization technology by curing-liquid vacuum concentration and ion exchange was proposed for low-salt drink production and crystalloid salt recycling; the waste sugar solution as well as by-product waste were recycled through filtration, clarification and decoloration by this technology. From a perspective of emission reduction, a combined biological and desalination technology was proposed for the treatment of wastewater aiming at its high salt and COD and highly variable water quality. Moreover, cleaner transformation and intensive development suggestions which could help to save water resources, reduce wastewater discharges and promote cleaner production level were proposed to promote the sustainable development of the preserved fruit industry.