The mission

Dongjiakou Economic Zone spans approximately 284 km2 and consists of a port area, steel industry sector, chemical industry sector, commercial area, and residential area. The zone has very high standards for treated effluent, and businesses located there find duplicate investments into environmental treatment undesirable. The zone wishes to make environmental protection more affordable and facilitate the government and environmental supervision. Another goal is to contribute to the region’s circular economy.

Our solution

A SUEZ joint venture has led the investment, construction, and operation of the industrial WWTP at Dongjiakou that provides industrial wastewater treatment (20,000 m3/day) and municipal wastewater treatment (3,200 m3/day) services for industrial and commercial clients in the Dongjiakou Economic Zone.

The primary treatment line uses the anaerobic-aerobic (AO) process to treat organic wastewater and domestic wastewater generated by enterprises in the zone. The secondary line uses the “high-density clarifier + V-shaped filter tank” process to treat wastewater, primarily from Qingdao Iron and Steel Group.

Customized solution for Qingdao Iron and Steel Group to enable 100% wastewater reuse in production

The wastewater generated by Qingdao Iron and Steel Group, a large Chinese metallurgical corporation located in the economic development zone, enters the WWTP’s water treatment system and goes through several stages – including a buffer tank, a high-density clarifier, a V-shaped filter tank, and a backwash tank – to produce treated effluent that meets Qingdao Iron and Steel Group’s reuse parameters. Effluent that meets all required control parameters recirculates through the pipeline to the company, where it can further treat the water and use it for production. In this way, it realizes true circularity.

Serving the zone with a centralized treatment solution to reduce resource and energy consumption

Following the Dongjiakou Economic Zone’s designation as a provincial-level chemical industry park in 2018, businesses in the zone switched to a centralized industrial wastewater treatment model, where most wastewater generated can be directly discharged to the WWTP for centralized treatment. This eliminates duplicate investment in environmental facilities by businesses and reduces the cost of environmental treatment. It also facilitates government and environmental regulator supervision and promotes a regional circular economy.

The result

  • Reusing 100% of the treated wastewater for enterprise production to enable water recycling
  • Operating in a centralized industrial wastewater treatment mode to reduce environmental management costs, facilitate compliance with government policy and environmental regulation. Promoting a regional circular economy
total wastewater treatment capacity
industrial wastewater is reused in Qingdao Iron and Steel Group
of the WWTP’s total treatment volume is reused water