CISDI creates a splash at Baosteel Zhanjiang  - world’s first intelligent water system with zero waste

Baowu Group Zhanjiang is seen as a benchmark for green steel development, and a leading force in China’s bid to ensure industry can co-exist in harmony with the environment.

An eco-partner in the city of Zhanjiang, it has now created the world’s first intelligent water centralised control centre at its steelworks.

Dozens of isolated water sub-systems and 160,000 points of data have been integrated onto a big data platform, which behaves as the smart brain for a zero liquid discharge system.

“Zhanjiang’s water system is symbolic of the eco-friendly advancement of the entire steelworks,” commented a company spokesperson at Baowu Group’s Green Development Convention, which was staged in Zhanjiang City on October 28.

“The scheme fulfills our master-plan targets for a plant-wide water system. It has three water sources – the Jianjiang River, desalinated sea water and collected rain water.

“It generates zero liquid discharge and has intelligent centralised control. We are China’s first ZLD and first intelligent water plant.”

CISDI, Baowu Group’s most crucial planner, designer and package-supplier, has been serving the Baowu Group’s steels division for six decades.

To meet the Group’s aim of becoming both a global leader in green steel methods and the world’s most efficient producer of prime-quality carbon steel, CISDI provided total solutions to the plant-wide water system in addition to the other sections of the Zhanjiang plant.

To achieve zero liquid discharge, most of the plant’s used water is recycled by internal users on-site and the rest will be multi-stage concentrated into industrial salts for external users.

Innovative water solutions

Baosteel’s quest for green developments has guided CISDI since the very beginning of its plans for the plant.

CISDI’s tailor-made water total solutions have now implemented that guiding principle and are resulting in reliable, advanced indicators.

Traditionally, steel plants have used huge amounts of water and the waste water discharged at the end of the process has caused serious water contamination.

When Zhanjiang Steel chose the East Sea Island as its site in 2005, the biggest available source of fresh water was the island’s Hongxing reservoir. But it is also the living water source for local people, which meant there was a limited supply for a 10-million-tonne steel plant.

Aware of the abundant sea and rain resources also available, CISDI figured out an innovative solution which utilised three natural water supplies:

1) The first source:

A dam was built on the Jianjiang River to the northeast of East Sea Island. Two supply channels were built, passing through a 40-kilometre section along the South Sanhe River and Kwangchowan to supply water to the plant. This method supplies 34 per cent of the water needed.

2) The second source:

A water reservoir capable of holding 1.20 million cubic metres of rainwater was built. Rain is collected from the plant and the 30km² region on its doorstep.

The reservoir collects 11 to 16 million cubic metres of rain a year, which equals the water volume of China’s West Lake in Hangzhou City in the Zhejiang Province. It can supply 40 per cent of the steel plant’s water demand. Cost savings on water are at $4.28 million.

3) The third source:

Dead steam from the power plant is used to power a low-temperature, multi-stage desalination process which turns seawater into pure water. This supplies 26 per cent of the plant’s water requirements.

The three sources solution has reduced the plant’s water consumption from 5.17m³ to 3.19m³ per tonne of liquid steel.

Waste water and sewage from the plant’s production units are all treated by the central water treatment plant and are recycled.

To prevent the discharge of waste water into the sea, CISDI studied production data and process verification and assisted Zhanjiang Steel in defining the ZLD solution of ‘recycle consumption plus concentration for salt extraction’.

By the end of September 2019, the entire ZLD project had been started up successfully, with all discharged concentrated brine being successfully extracted as salts by MVR (mechanical vapor recompression).

Creating the smart brain for ZLD

The world’s first intelligent water centralised control centre has been performing well at Zhanjiang Steel.

Data is being integrated with high efficiency and the full process is being real-time monitored. Workforce productivity has been improved and the centre is reducing water consumption, making production cost savings and preventing waste water discharge.

Achieving zero liquid discharge had been a difficult factor in Zhanjiang’s high-efficiency management and control.

Because the water system spreads across the entire plant and water quality and flow rate are closely related to production processes, any abnormal fluctuation in working conditions would affect the water supply and return, causing it to become too excessive or too deficient.

Operators and schedule planners were based across 15 operation rooms and could not interlink efficiently. In spite of telecommunication interfaces, data in information systems across the plant was stored in isolation, which meant they were unable to support water volume dynamic matches.

To solve these substantial problems, CISDI proposed a concept which would break through the original system’s framework and organisation boundaries and enable it to match production process flows and make the information couple with water volumes.

This was achieved by employing the CISDigital industrial internet platform to collect into the water big data centre 160,000 points of data from dozens of isolated systems and over 100 cameras.

CISDI’s Q-Touch system generates a plant-wide water balance sheet and outputs a production monitor drawing.

Sigma AI algorithm, an intelligent dosing system and CISDI’s Nudge-plus platform are all used to empower the integrated links and centralised control on remote operations.

Since the start-up of the intelligent water centralised control centre at Zhanjiang Steel on October 1^st, a highly-fused CPS (cyber-physical system) has been formed. The integration of the technological process, management and data has enabled a new water operation, control and management mode.

The centre is the smart brain of Zhanjiang Steel’s water system.

It is achieving long-distance, mass centralised control, interconnected information flow from raw water supply and preparation to user delivery, recirculation and the centralised treatment of waste water for recycling.

The wide interlinks are demonstrated between employees on different duty levels, between machines in different closed-loop systems and between man and machine across procedures.

This deep system and duty integration has upgraded and optimised comprehensively Zhanjiang’s production control.

The intelligent water centralised control centre also manages Zhanjiang Steel’s Phase I hot mill circulating water, cold mill water treatment, steelmaking and continuous casting circulating water and blast furnace circulating water systems.

Phase II of construction will introduce more water systems but their data will be managed by the centre, therefore additional operation rooms will not be required.

By upgrading safety, efficiency, energy conservation and environmental protection, Zhanjiang Steel’s intelligent water system is another success story in Baowu Group’s bid to build a green steel community.

An aerial view of Phase 1 in operation at Baowu Group’s Zhanjiang Steel

Zhanjiang Steel’s water reservoir has a volume of 1.20 million cubic metres, the largest in China’s steel industry. It collects around 12 million cubic metres of rainwater a year, providing Zhanjiang Phase I with approximately 30 per cent of its fresh water requirements.

The CISDI-built intelligent water centralised control centre at Zhanjiang Steel