Sustainable Solutions for the Metal Recycling Industry
Digitization and Sustainability
Digitalization and sustainability are gradually picking up speed in our sector and, for us, both have strategic priority. We are transforming ourselves from an engineering company to a full service- and solution provider for our customers, investing even more in new and more efficient technologies, and increasingly devoting ourselves to environmental issues such as the reduction of emission values through the latest dedusting systems – 360° along the metal recycling value chain.
All LINDEMANN machines are equipped with quality and technology relevant to steel processing and compliant with the green steel cycle. With a look at the large shredder systems from LINDEMANN, it also quickly becomes clear that the company has long since assumed a leading role in terms of environmental protection. From material preparation of scrap, separation of fractions, and proven reduction of emissions to results analysis which evaluates the purity level of the processed material:
Variable Frequency Drive
The shredder rotor must cope with constantly changing performance demands due to discontinuous material feeding of the machine. If the shredder rotor is loaded with process material, the rotor speed decreases briefly. The motor then tries to accelerate the large inert mass of the rotor back to
nominal speed as quickly as possible. This constant change between acceleration and deceleration of the shredder rotor places high demands on thermal management and speed control of the motor.
The efficiency of shredder operation is thus largely determined by the quality of motor load monitoring and speed control. The aim is to return to nominal motor speed as quickly as possible.
Our solution: A robust and high-performance medium voltage variable frequency drive (VFD) that makes the shredder drive highly consistent.
Advantages compared to conventional drive systems:
Fast and accurate motor control over a wide speed range. Active deceleration and regenerative braking as possible options.
Energy efficient system with lower electrical energy losses (energy wasted as heat in conventional drive systems).
No gearbox and no hydrodynamic coupling required, thus effectively reducing the number of components that need periodic maintenance or can fail and cause production stops.
Intelligent material feeding due to interaction of the Shredder Drive Assistant (SDA) and the VFD, resulting in optimal motor utilization, damping of load peaks, and leveling of production, saving of energy, increased productivity, and potentially reduced wear of mechanical components.
Advantages compared to low voltage drive concepts:
Excellent performance in terms of network disturbances (voltage sags, flicker, harmonic emissions etc.) as caused by load peaks. The plant can be operated on full capacity even while connected to a relatively weak electrical network, and potential penalty costs for excess energy drain and network disturbances are greatly reduced.
High reliability, robustness, and efficiency of the VFD.
High input power factor with very low input harmonic distortion.
High starting torque without inrush currents and starting current peaks.
Lower motor and drive electrical energy losses during operation.
Low VFD maintenance requirements.
Shredder Drive Assistant
The Shredder Drive Assistant (SDA) ensures that the shredder is fed with material in such a way that it operates at optimal capacity without exceeding the breakdown torque, and that the shredder driver’s workload is reduced through efficient support. These measures enable a constantly high throughput rate in t/h while at the same time minimizing the number of standstills. In addition, the SDA enhances the shredder’s production output by increasing the limits of the driving pulley stop (material feed stop) within a reasonable range. The main motor current and the temperature values of the drive train components are captured and evaluated. The higher the shredder loading, the higher the main motor temperatures. The lower the loading, the lower the temperatures.
- Constant throughput at a high level
- Reduction of expensive current peaks
Supports the Shredder Operator:
- Technological optimization monitors and controls operating parameters
- Operator role shifts to a supervisory function, monitoring and interacting with critical material feeds
- Permanently filled shredder chamber
- Lower cost per ton due to reduced wear.
Operating and production data acquisition system
InDEx – INTELLIGENT DATA EXTRUCTION
All machine data can be visualized and analyzed in the InDEx web portal and app. The data can be transferred to programs and systems designed for controlling purposes, if required. Directly to the end device.
Perfect basis for evaluating the various key performance indicators (KPIs). InDEx enables the workflow and performance of one or several machines to be optimally monitored and evaluated. Free from unpleasant, expensive, or unproductive surprises. Whether on a business trip, via mobile app, or from the dashboard: One click is all it takes to immediately determine how high the current capacity utilization is, which material is currently being processed, how many operating hours the system has been running and the general condition of the machine.