Siemens management system cuts energy costs of electrostatic precipitators in steel mills

With Precon, Siemens Metals Technologies is offering steel works operators an energy management system for electrostatic precipitators in dedusting plants. The system includes components for data recording and processing, operator control and monitoring devices, and special software for controlling the precipitators.

This enables the operation of the electrostatic precipitators to be matched optimally to the actual operating state of the converter. Depending on the environment and the type of electrostatic precipitator used, the energy consumption can be reduced by between 30 and 50 percent. The first Precon systems are in operation in a European steel plant.

With the same dedusting performance, the precipitators there are saving more than 60 percent of their electrical energy consumption. The system typically pays back within one year, and can be retrofitted in existing plants without any additional shutdowns.

The electrostatic precipitator forms the heart of primary dedusting plants in steel works. It can remove around 99 percent of the dust from converter offgases. There is a direct voltage of up to 65 kilovolts between the discharge and collection electrodes. Depending on the size of the plant, the energy consumption varies between 1.4 and 2.1 kilowatt hours per metric ton of tapped steel. Therefore electrostatic precipitators are a major cost factor. The precipitators are usually operated so that dust concentration limits can be reliably maintained. However, as the dust emissions at the converter fluctuate widely in time, this operation practice is not in line with demand, and simply leads to higher operating costs.

Precon takes into account the various operating states of the converter throughout the complete cycle, and regulates the energy use of the precipitator to match current process conditions. This is achieved by precisely monitoring the power consumption of each individual precipitation field, and by a special software to evaluate all the relevant process data. On this basis, the high-voltage supplies to the precipitation fields can be controlled and optimized. The system includes pre-tested hardware, a Siemens Nanobox industrial PC, and an integrated programmable logic controller for communication with the high-voltage components of the precipitators. A touch panel facilitates user-friendly operation of Precon. If necessary, the system can be quickly switched from normal to optimized operation. There is no difficulty in retrofitting it in existing plants, and this can be done without any additional plant shutdown. A test system for determining the potential savings of a precipitation plant is also available.

For further information on solutions for steelworks, rolling mills and processing lines, please see www.siemens.com/metals

Siemens AG (Berlin and Munich) is a global technology powerhouse that has stood for engineering excellence, innovation, quality, reliability and internationality for more than 165 years. The company is active in more than 200 countries, focusing on the areas of electrification, automation and digitalization. One of the world's largest producers of energy-efficient, resource-saving technologies, Siemens is No. 1 in offshore wind turbine construction, a leading supplier of combined cycle turbines for power generation, a major provider of power transmission solutions and a pioneer in infrastructure solutions as well as automation, drive and software solutions for industry. The company is also a leading provider of medical imaging equipment – such as computed tomography and magnetic resonance imaging systems – and a leader in laboratory diagnostics as well as clinical IT. In fiscal 2014, which ended on September 30, 2014, Siemens generated revenue from continuing operations of €71.9 billion and net income of €5.5 billion. At the end of September 2014, the company had around 357,000 employees worldwide.

Further information is available on the Internet at www.siemens.com

Reference Number: PR2014120078PDEN

Contact
Mr. Rainer Schulze
Process Industries and Drives Division
Siemens AG

Turmstr. 44

4031 Linz

Austria

Tel: +49 (9131) 7-44544

rainer.schulze​@siemens.com