It took 9 months, half a month ahead of contractual schedule, to complete construction, and attained the set capacity one month ahead of schedule, after such milestones as signing contract in last July, starting construction on last September 1 and entering test run on this June 2. All the output indicators were shown superior to the guaranteed figures.

 

This project was designed for collecting and treating the plant-wide waste water from Hebei Jingye Steel in capacity of 36,000t/d and for realizing zero discharge. It’s CISDI’s another typical key project of applying self-developed technology after the services for Xinjiang Bayi Steel. Through serious studies on client’s needs and surveys on the production drainage water and quality, CISDI proposed the pretreatment process of highly-efficient settling tank + V-shaped filter tank, which could enable to feed the required water for deep processing, and adopted dual-membrane process of ultra-filtration + reverse osmosis to further treatment of waste water, which could get it to desalted water quality and be recovered to the demineralized water stations and desalted water stations in the whole plant. During those processes, there was some highly-salted concentrate generated from the system, which would be RO-treated again for reduction of discharge; the small quantity of the concentrate water could be fully used for blast furnace slag granulation and converter slag at the hot closed pot. In this way, the zero liquid discharge (ZLD) has been actualized in real sense.

 

Thanks to the most advanced technology for maximizing the water resources utilization and minimizing the waste discharge, Jingye Steel whole plant can have 36,000t waste water treated per day and 31,000t desalted water recovered from the ultra-filtration and RO process system, equivalent to half of the fresh water demanded by all the users of the plant. And the 2-stage RO processes can treat the system generated concentrates and send the final output to ironmaking and steelmaking for use up. Such a ZLD project is creating observable benefits in environmental and economic aspects, not only saving water but exerting no pollution to downstream environment, reducing COD discharge by 657t/a and suspended matter discharge by 1,051t/a.