Maximise returns on safety investments with integrated approach

Process plants worldwide and in India are scouting for technologies that ensure safety of their personnel and equipments, in addition to achieving improved productivity. Proper safety precautions are necessary to keep the plant in a safe mode. Integrated safety not only ensures continued production but also takes care of emergency situations.
 
Generally, process plants that handle toxic, flammable or explosive materials use Safety Instrumented System (SIS) to protect personnel, plant and environment. The chemical industry, which comprises of sectors such as oil and gas, HyCO or syngas, generally deals with such materials and, hence, forms an important market for SIS providers. In Indian chemical industries, while automation is widely used, it is the adoption level that varies depending on the level of complexity involved in the processes. Historically, a BPCS (Basic Process Control System) or DCS (Distributed Control System) was used for process applications and a separate SIS was used for the safety applications.
 
Let us understand how this system works. Separate controllers (Central Processing Units) or Automation Systems (AS) are used for DCS and SIS. Consequently, different communication buses have to be used for communication with DCS and SIS inputs & outputs.
 
Furthermore, DCS and SIS function on different engineering and operating environments, causing difficulties in integration of DCS and SIS. It is important to note that plant owners also need to impart two different sets of trainings: one for DCS and one for SIS.

ALSO READ: Optimising gas processing assets using process modeling tools
 
In today’s competitive marketplace, plant owners generally aim to achieve a reduced Total Cost of Ownership (TCO), faster time-to-market, reduced CAPEX (capital expenditure) & OPEX (operational expenditure). An effective method of contributing to the company’s bottom line is by reducing the investment on SIS, without compromising on safety and availability. The next generation of automation systems - Integrated Safety Systems - provide integrated solutions by using the same hardware and similar monitoring and operating environments, without compromising on plant safety and availability.
 
Benefits of integrated safety systems
With integrated safety systems, the investment is limited to a single common system and a unified communication bus. A single controller can handle process as well as safety related functions, (though the user may choose to go for a separate DCS and SIS). With integrated safety, DCS & SIS inputs-outputs can be connected to the same controller. The user has the freedom to place the input-outputs either in the same rack or in different racks.
 
The communication between the Common Automation Systems (DCS & SIS) and input-outputs happens over protocols such as Profi-Safe, which has mated safety with industrial communication. This has a huge saving potential towards CAPEX & OPEX. Integrated safety brings down cable, panel & floor space, training requirements - all of which reduces CAPEX. Integrated safety also increases the ease of maintenance and facilitates faster debugging thereby reducing OPEX and increasing the plant availability. Also, faster start-up and operation time reduces the time-to-market, a key differentiator in today’s connected world.
 
Most importantly, integrated safety systems are designed on a homogenous engineering and operating environments. This means that training costs are drastically reduced as plant operators need to be trained only once on the integrated safety systems. Furthermore, the easy integration of DCS & SIS at the Operator Station (OS) level means that operators get a clear and comprehensive view of both the process and safety areas of the plant. It goes without saying that better visualisation enables better control of the plant, further enhancing operational excellence.
 
Simple to integrate
Can companies using conventional safety procedure incorporate integrated safety concept? The answer is quite simple: A resounding yes! Profibus International, an industrial consortium of automation suppliers, has mated safety with industrial networking to create solutions for ‘built-in’ safety based on all available media, including Profibus DP and PA, Profinet, and wireless technology.
 
ALSO READ: Process equipment makers ready to ride investment cycle boom

End-users are now taking advantage of these solutions to unify their network architectures and eliminate the need for a second, parallel bus while achieving safety integrity levels up to SIL3. Furthermore, because process instrumentation customers have made substantial investments in existing Profibus PA-, HART- or Foundation Fieldbus H1compatible process field devices, the adoption of any new technology will be evolutionary, rather than revolutionary.
 
In a nutshell, by using integrated safety systems, plant operators can reduce inventory costs, reduce training costs, enjoy better diagnostics and visualisation, and reduce control room floor space without compromising on safety.
____________________________________________________________________________________________________
The Author is the Head of Vertical Sub Segments (Process Automation) at Siemens Ltd