Demag, Germany, will supply Green Steam Hürth GmbH, a subsidiary of E.ON, with three process cranes equipped with grabs for a heat and power plant project. The project comprises the build of a biomass power plant with an output of 20 MW of electricity and 87 MW of heat energy at the site of the UPM paper plant in Hürth near Cologne, Germany. This project be the first to make use of Demag Remote Operating Stations (ROS), which enable the remote control of crane systems.
Managing Director of Demag, South Africa, Emil Berning said “This is a Demag milestone, where our innovative ROS, which sees the first use of Demag remote control of crane systems, is to be utilised in a brand-new European power plant project. The ROS system is a new addition to our previous offering of two variants for the control of process cranes, and its brand new Demag technology that enables the operator to control the crane from any convenient working environment”.
The power plant, where E.ON is investing some EUR 110 million is due to go online in mid-2022 and will provide heat for the Hürth paper factory whilst at the same time, feed renewable energy into the grid. UPM produces more than 300,000 tonnes of high-quality newspaper made from recycled paper at the factory every year.
The paper production operation needs a lot of heat (in the form of steam) and the combined heat and power generation is particularly efficient. In this case, it is also particularly sustainable, since the power plant is fueled by wood residues, which E.ON procures in the region. According to E.ON, this will provide an efficient and reliable supply of virtually CO2-neutral energy to an industrial operation that requires a lot of energy.
Demag will deliver two process cranes for the automated continuous supply of wood to fire the boiler in the power plant. Some 45 tons of wood need to be fed around the clock every hour. The two double-girder cranes, which have a load capacity of 14 tonnes and a span of 20.6 meters, will travel on a crane runway measuring almost 100 meters in length. All of the crane travel drives feature variable speeds; energy recovery when braking and lowering loads enhances the energy efficiency of the cranes. Hydraulic multi-jaw grabs with a capacity of 12 m³ will be used as load handling attachments.
Cranes continuously feeding fuel
The crane systems will largely operate in automatic mode. The Demag Warehouse Management System (WMS) software will ensure, for example, that the bunkers are cleared, that the boiler is continuously fed with the required quantities of wood and that both cranes complete their coordinated tasks.
Not only the fuel, but also the ash as a residual material is handled by a Demag crane. The Demag engineers have specified a smaller double-girder process crane with a 5.4-tonne load capacity and a hydraulic grab for this task.
The three crane systems will operate under challenging conditions with high humidity (up to 100%) and high dust levels. They are ideally suited to meet these requirements, as Demag has already designed and delivered many cranes for refuse recycling installations and biomass power plants all over the world.
Demag ROS: crane control system with multiple views of the operating location
Since it is very difficult to view the entire very long fuel bunker from a conventional crane cab, the project engineers at E.ON decided in favour of a special Demag option. If the cranes need to be operated under classic manual control, this can be done via a ROS, which also serves as a monitoring station when the cranes are running in automatic mode.
ROS is a remote control station that includes all operating functions of a process crane with a crane operator seat – except that the operator does not view the crane and its operating environment direct, but via a widescreen monitor that shows images from several cameras in real time. The screen layout can be configured to meet process requirements, with information relevant to the process being automatically displayed.
A ROS station like this can be located very far from the crane and at the Hürth biomass power plant, it is installed in the control centre, so the operator can benefit from improved working conditions.
The many installed cameras ensure he has an even better view of the process than from a crane cab. This is because the cameras can also “look” where the normal field of vision would be restricted.
Berning commented that in simple terms, the ROS is a complete, location-independent operating station for cranes. The operator has access to all the control elements that are normally installed in a crane cab. “Just as in the cab, the control unit can be optimally adapted to meet the operator’s needs. With ROS, however, the owner can decide where the “virtual” cab is located, and that makes for greater flexibility while still offering all the standard safety checks. I see many applications in energy and industrial sectors in South Africa benefiting from this new Demag technology, making specialised crane activities easier to manage”.
“With the ROS system, all control elements are compactly and ergonomically integrated into a console panel, the height of which can be adjusted so that no matter where the crane is located, it can be operated from either a sitting or standing position. In addition to the usual joysticks with adjustable armrests, a touch panel or – or if the user chooses – a tablet can be used as a human-machine interface, via which the operator can call up additional information” said Berning, adding “This third ROS system makes cab training easier and also significantly reduces investment and operating costs because no cabs need to be installed on the cranes themselves and access to the cab is not needed” concluded Berning.
Demag, South Africa