There will always be paper. Despite the digital or so-called paperless age, the paper industry is still booming in Germany. This means that bleached long-fibre cellulose, which is used to produce fine and printing paper as well as high-quality sanitary paper, also remains very much in demand. The high demand induced Mercer International, an American-Canadian pulp and paper manufacturing company, to set up a new cellulose plant in the north of the German state of Saxony-Anhalt.
Naturally, the good infrastructure and the favourable location in Central Europe were also important prerequisites to warrant an investment of a total of one billion euros. In addition, some 580 new jobs were created, making the modern plant, which started its production in the summer of 2004, the largest employer in the region.
On business premises close to 200 acres in size, Zellstoff Stendal GmbH processes about two million solid cubic meters of log wood and one million solid cubic meters of wood chips to obtain 570 000 tons of cellulose each year. The logwood is debarked in the direction of the fibre, chopped up and cooked using heat and chemicals in a pulping process. The resulting pulp is then washed, sorted, bleached, drained, dried and shaped. In the so-called leaching line, the chemicals used are recovered and returned back into the production process.
Sustainable and environmentally friendly
The entire production process is sustainable and environmentally friendly. In Germany, for example, more wood grows than is harvested. The extraction liquid and the sludge that are produced during the CO2-neutral burning of the scrap wood, cover not only the plant’s relatively high-energy consumption (55 MW), but they also feed another 35 MW into the public power network.
To reliably monitor the cellulose production process, Zellstoff Stendal GmbH uses a total of 58 Mobotix cameras.
“Many areas in the production plant are too loud, too warm or too dangerous for our employees. But production in these areas still has to be carefully monitored,” said Kay Heppner, system manager at Zellstoff Stendal, explaining the reason for the relatively large number of surveillance cameras in operation.
That is why the Magdeburg branch of Siemens AG was already commissioned to prepare a comprehensive communications concept for a data network during the project planning phase. The concept was to be designed not only to accommodate data and telephony services, but also for the transmission of images, which would then be directly displayed in the production control rooms.
Analogue too complicated?
“We need these images live and in good quality to guarantee optimum monitoring,” continued Heppner. “After all, without a properly functioning camera system, we would not be able to run the production lines. A camera malfunction would automatically mean production downtime at our plant.”
Providing good-quality images live used to be a task that was generally performed by analogue video technology. “But that would have meant an awful lot of complicated wiring,” said graduate engineer Axel Borchers. As the network expert at Siemens, Borchers was in charge of preparing the communications concept and supervising the project.
“For the digital data and voice services, we had planned to use a fibreglass/copper network to connect all 25 buildings on the extensive premises. To provide analogue video technology, we would have also had the complicated task of laying another cable along with installing the cross bars required and the corresponding monitors.”
This was enough reason to start thinking about whether or not there was an IP camera that had a frame rate able to do the job and that could easily be hooked up to the already-planned digital network. “In the past, we had already had very good experience with the network cameras from Mobotix. The tests we then performed indicated that these cameras offered the image quality we needed, thus meeting all the necessary requirements. That is why we recommended this technology in our communications concept,” commented Borchers.
“Of course, at the same time, we looked at a number of different systems and discovered that, in terms of quality and expansion options, Mobotix offered the best system overall,” added Heppner. “The camera does not have any mechanical parts and it is extremely robust. In addition, it has no problems with fluctuations in temperature and is able to deal easily with different degrees of brightness as well as backlight. In short, many of the details and features it is equipped with are also things that we urgently needed to monitor our production processes.”
At every location
The system manager is also enthusiastic about the camera’s flexibility: “I can connect the camera to any point in the network and make the image it records available to any other point with a normal PC or notebook. In the control room, the camera images can be easily switched to another monitor. Servicing and maintenance are also hardly needed. Besides, I can even log on at home to alter the configuration of a camera or change other settings.”
Although a total of three services at Zellstoff Stendal is now routed via a data line, there have been no adverse effects on system performance. Measurements have shown that the network load of the communications network is exceptionally low even when video images are being transmitted, something which can surely be attributed to the amply dimensioned 100 MB (copper) or 1 GB (fibreglass) lines as well as to the fact, that despite its high performance, Mobotix technology requires only an extremely low data rate
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