BRAZIL / ETHANOL:The biggest Ethanol plant in the world has been successfully commissioned using a Smar PROFIBUS Automation System. The plant, at Jatai, Goias state, belongs to the COSAN Group. It is equipped with two turbines generating 65 MW, and it mills 21,000 tons of sugar cane per day, producing 2,249 m3 of ethanol. According to Fernando Liboni, the project manager from Smar, this is a modern plant using PROFIBUS with System302 Smar Automation System. There are 800 Smar PROFIBUS PA devices, including pressure and temperature transmitters, and valve positioners in different areas of the plant, including Utilities, Juice Preparation, Fermentation, Syrup Treatment, Distillation, Power Generation, Water Feeding & Treatment, Steam Boiler and Diffuser. There are 14 redundant operation stations arranged in a modern control room, everything integrated and operated by a System302 from Smar. According to Mr Armando Viotti, Cosan Group Operational General Director, the plant shows “auspicious and positive results.” He highlights the importance of the PROFIBUS automation system from Smar in delivering the results and benefits. Watch video here.

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BELGIUM / CANAL MANAGEMENT: Waterwegen en Zeekanaal's responsibilities include the Leuven-Dijle canal (comprising 15 structures such as bridges and locks over a distance of 30 km) and the Bruxelles-Escaut Maritime Canal (with 16 structures over 30 km). Traditionally, (and sometimes still today), locks and bridges were controlled by a keeper. Often, keepers were in charge of two or three structures if they were located within easy reach by bicycle or moped. Today, an effort is underway to centralize the control of all these structures. The Kampenhout central control station will be in charge of four locks and ten bridges on the Leuven-Dijle canal.

Local automation retained
A single lock, located at Zennegat, near the confluence of the Dijle and the Senne rivers, maintains local control due to the volume of work and because it is a tidal lock (and therefore busy from 6:00 a.m. to midnight). Each engineering structure has retained its existing automation system based on a local PLC. These support automatic execution of the main functions, i.e. stopping traffic, opening the bridge, closing the bridge, and the reverse maneuver in case of trouble.

A complete “operator console” has been preserved at the local level, with former pushbuttons replaced by a touch screen PC. Local control is the same as control at the centralized control station; however, to allow for maintenance, it can also support local operation of the different steps in sequential order.

Centralized control
Kampenhout will comprise three dual workstations (two of which are already in service). Willebroek will have seven to control the Maritime Canal, plus one for diagnostics and remote monitoring. Each workstation is equipped with four to six video screens, three pushbuttons (coupling, emergency shutdown and reverse) and one touch screen (displaying a real-time image of the bridge or lock control). This allows the operator to control two structures at the same time. The workstations are linked to the servers via KVM (keyboard/video/mouse) modules and a multi-cable. These are the servers that are connected via Ethernet fiber optics to the local PLC control of each structure. A PROFIsafe network is planned via a separate fiber-optic connection.
Alongside of and in support of the “control,” voice and video communication is supported via Ethernet. The voice communication consists of a one-way audio channel from the control center to loudspeakers located around the structure, plus a two-way radio connection via marine telephone, also using fiber optics.

Emergency shutdown
By pressing the “coupling” button at a workstation, an operator can request authorization to control the structure from that control console. This initiates a connection procedure via a fiber-optic Ethernet connection. If the connection is OK the emergency situation is lifted at the engineering structure via a procedure on the safety PLC through the fiber-optic PROFIBUS connection (via PROFIsafe).Only then can the actual control begin.

A requirement was that the signal from the emergency switch should always be transferred within 100 ms to the local back-up circuit. Given the large distances the choice was made for fiber-optic PROFIBUS, OLM Hirschmann (electronic/optic converters) and ET200S safety I/O.
The activation of the entire PROFIBUS safety network is monitored via PROFIsafe, whereas the safety I/O control the safety connections locally. At the slightest interruption of this network, operation of the engineering structure switches automatically to the emergency shutdown procedure.

A t the time of the public tendering in 2001, the availability of PROFINET, long-distance switches from Siemens and PROFIsafe on PROFINET made it possible to eliminate a large number of switches/amplifiers and to reduce response times. The result is a response time of 50 ms, half the time required in the project specification. The safety PLC also ensures that the operator sees images of the selected structure, rather than images of another structure.

Three engineering structures on the Leuven-Dijle canal have been operated by remote-control since September 2006. The next four are under conversion now. The PROFINET connection between the Kampenhout and Willebroek control centers has been fully implemented and tested.