FLSmidth, a world leader in Electrostatic Precipitator technology, develops advanced pollution control systems in order to comply with the stringent industrial standards. Particle removal efficiency is controlled in real time by sophisticated micro processor based voltage controls. FLSmidth decided to integrate HMS' communication system to inform their users of the status of the air pollution control equipment. Because they were able to implement this interface with a standard and an easily integrated solution, they selected HMS Industrial Networks.

An electrostatic precipitator (ESP) is a particulate collection device that removes particles from the gas stream using the force of an induced electrostatic charge. The electrical field collects the dust on collecting plates. Automatic plate-rapping systems and hopper-evacuation systems remove the collected particulate matter while on line, theoretically allowing ESPs to stay in operation for years at a time.

In the steel industry, where HMS equipment has been implemented air pollution control equipment must be able to collect a large variety of pollutants. Because ESPs can collect very fine, dry particles, abrasive and corrosive particles, it is often a preferred solution in this industry. ESPs have to cope with 2 phenomena that decrease the efficiency. First is the Spark effect: this is a short circuit between the plates inside the ESP. No dust collection is possible during this period. The second is the Back Corona effect: positive ions are produced in the dust layer and can be emitted back into the gas.

The ESP implemented by FLSmidth is a very high tech solution. It integrates the newest CoromaxTM pulse power supply system, which is the most advanced high voltage system on the market. CoromaxTM differs from traditional DC power systems by offering unique control on electrical particles, which are charged during 75 microsecond impulsions at 140 kV, while the mean voltage is 40 kV. Currents can also be controlled. By applying very short electrical pulses, CoromaxTM enables the reduction of sparks. Because there is no current, the back corona effect is also reduced.

Sophisticated, proprietary microprocessor high voltage controls respond quickly to process variations, or upset conditions. This control system enables fast response controls and it ensures outlet emissions remain low even under challenging process conditions. Electrostatic precipitator performance is capable of achieving less than 5 mg/Nm? emission.

By applying pulse systems, existing ESPs can be improved without physical enlargement while reducing the power consumption at the same time. New ESPs can be installed with smaller dimensions than ESPs with traditional DC power supplies.

Real-time monitoring system

"For such an advanced control system, it is critical to inform the final user. This is what HMS products do," explains Deepa Kirubakaran, for FLSmidth in India. HMS products enable the communication of all information concerning the equipment status and the real time emission control system.

Deepa Kirubakaran adds: "We have chosen HMS, because we found a standard product which is very simple to integrate and very compact. The key issue is that with only one module, you can handle all the signals." Products utilised were a Java version of Serial to Profibus Gateway and a Java version of Serial to Modbus RTU Gateway.

HMS Industrial Networks is distributed in India by UL Electrodevices Pvt, which is based in Pune. Umesh Sakle, who brought the technical support, explains: this gateway, Anybus? Communicator, can connect almost any automation device with a serial communication interface to Fieldbus and industrial Ethernet networks. The Communicator performs an intelligent conversion between the serial protocol of the automation device and the chosen industrial network. It is compatible with all leading PLC manufacturers and almost no programming is required! Another great feature with the Communicator is the Save/Load function. Once you have completed your serial configuration for one network, you can easily re-use the configuration for another Communicator supporting a different industrial network.

"This implementation is a success. We can use the HMS solutions for our future projects," concludes Deepa Kirubakaran.

FLSmidth is the world?s largest supplier of cement plants (with more than 3.3 billion euro turnover). Within the steel industry, FLSmidth has implemented more than 450 installations. Upgrading existing sinter bands with CoromaxTM pulse power supply system is one key market.

HMS Industrial Networks is the leading independent supplier of embedded network technology for automation devices. UL Group is the HMS Industrial Networks' representative for India. It distributes, manufactures and develops products and services to cover the whole automation, machinery, electrical and electronics businesses.

(UL Electrodevices Pvt Ltd, Pune. Tel: 020-26960040. Fax: 91-20-26962079. Email: anybus@ulepl.com)