Major SCADA application for Le Havre wastewater treatment plant

The new water pollution treatment station of the greater Le Havre (CODAH) has a capacity of 415,000 equivalents inhabitants. The plant’s biological treatment uses the CyclorTM process, a technology patented by DEGREMONT. This process ensures the biological treatment and clarification process phases in a same pool, offering a genuine alternative to typical extended aeration processes. It is particularly suited to rejections in sensitive zones, and meets European requirements on nitrogen and phosphor treatment.
 

A customised SCADA application with Topkapi  

To offer a highly competitive production cost in spite of a sophisticated process, DEGREMONT standardized the CyclorTM process, from basic equipment to automation and supervision.

The overall design of the control-command system also meets this optimization requirement:

• decentralized architecture of automation components simplifies the facility: the distributed Advantys input/output units, regulators (over 50), starters, motor protections and measurement units are located close to the equipment, and connected to redundant controllers (Premium, Schneider Electric) through a serial Modbus network or IP Modbus over Ethernet
• the use of self-healing loops and separation of the Ethernet networks for automation and supervision improve availability
• the use of two redundant Topkapi servers allows to control the facility from operating stations located anywhere in the facility. Therefore, the plant does not need many local control boxes.

About the latter point, the idea of having no local controls seemed impossible a few years ago, for safety purposes.
Thanks to the reliability offered by the controllers, networks and the TOPKAPI supervision system, it has become possible to control the plant safely from ‘all digital’ operating interfaces, and no longer from ‘wired’ systems. Thanks to the centralized application, all modifications are made in a single point, allowing to protect against their transfer in the different local control interfaces, an offering subsequent maintenance savings.

The operators can also run commands from any point in the plant, without 'ties’, with all controls and settings they are authorized to use at their finger tips, and those only. Operation traceability is hence perfectly ensured.

Topkapi: meeting the requirements of an integrated control system 

Optimization of the implementation time of the supervision application is related with several functions meeting the requirements of a modern integrated control-command system (ICCS).

The main items are:

• Use of single data sources to automate setting: for example, engineering data files or dynamic links with Unity Pro; the double approach of ‘descending’ data and transverse exchanges with controller programming allows to combine the automation objectives of application creation and capacity to ensure the application maintenance.
• The production of standard objects such as those associated with the CyclorTM process: a few dozen entries (or a file import) generate several thousands of monitoring variables specific to this part. Therefore, the test procedures are also considerably lightened and more reliable. Several dozens of CyclorTM installations have been implemented.
• The ‘structured objects’ approach for the database allows integrators to adapt their know-how to project specifics, without wasting time in repetitive operations.
• Thanks to the client/server architecture, a modification on the central application is replicated automatically on all 20 operating stations.
• The implementation of Topkapi redundancy is easy and fast, as confirmed by Pascal Gonzalez, from the company ALLEZ, who ensured the integration for DEGREMONT.

 
As a conclusion, this application illustrates perfectly the evolutions and progress of Topkapi system over the last few years:

• high quality supervision allowing perfect integration into a decentralized architecture and offering extensive process control from anywhere.
• improving process operating requires monitoring an increasing number of parameters. This growth does not always induce an increase in the cost of applications, considering permanent improvement in the productivity of the tools.