Safety System Automates Burner Control System

Evonik Industries is a global leader in specialty chemicals, an expert in power generation from hard coal and renewable energies, and one of the largest private residential real estate companies in Germany. Evonik is active in over 100 countries around the world. With the product lines Carbon Black, Silica, Aerosil and Silane, the business division Inorganic Materials is one of the most important strategic activities of Evonik Degussa GmbH. Carbon Black remains the dominant reinforcing filler for the rubber industry, in particular for manufacturing tyres, but also with diverse uses in paint, printer colours, ink and synthetic materials. With 1.2 million tonnes, Degussa is the second largest producer of Carbon Black. The Evonik Degussa GmbH factory near Cologne, Germany, is the largest European producer of carbon black. During the production of carbon black, the residual gas is used for steam and electricity generation in the thermal afterburning plant. If a boiler stops functioning, however, a gas flare system starts operation to burn the residual gas. As part of renovation work, the boiler control and monitoring system for the gas flare was automated using the safety system HIMax. The solution included two HIMax-CPUs, two system bus modules, two digital output and three input modules, one analogue input module and one communications module for PROFIBUS-DP. The function of these components is to maintain overall correct operation, particularly in regard to the pre-ventilation period, flare monitoring and correct operating parameters. Lutz Dross, PLT planning and process engineer for the IM business division Evonik Degussa GmbH, values the possibility to conduct online tests with HIMax as well as the diverse programming possibilities. “The high level of flexibility guarantees low costs during the entire lifecycle of HIMax. Another advantage is that the safety system can be easily expanded without interrupting operations.” The new safety control system from HIMA guarantees the highest possible level of availability, Dross added. Whether during a hardware or software upgrade or routine maintenance work, HIMax doesn’t have to be turned off – the plant continues to operate. The safety system HIMax for large and medium- sized applications allows for uninterrupted operation of processing plant over its entire lifecycle. It is based on the Nonstop XMR technology that combines diagnostic- based SIL 3 safety integrity with a scalable fault-tolerant architecture that eliminates false trips and provides for unlimited changes, modifications, expansions, upgrades and regulatory proof testing without taking the plant off-line. The HIMax system is integrated into the Foxboro processing control system (DCS) via PROFIBUS-DP. Because of the open standards protocol, HIMax can be integrated with all leading DCS. In this way, controls can be combined with the best-suited DCS. The software tool SILworX proved to be another major benefit, said Lutz Dross, because of the fully integrated configuration, programme and diagnosis environment for HIMax. The modern user interface contributed to a reduction in mistakes and accelerated planning and implementation. “HIMax is exceptionally user-friendly. The software tool SILworX has a fully-graphic drop and drag programming function. That simplified engineering enormously,” said the management technology specialist from Evonik Degussa.