A large scale process pilot plant designed to support the next stage of gas-to-liquid (GTL) technology development is benefitting from a number of operational efficiencies as a result of utilising Siemens’ SIMATIC PCS 7 process control system.
The benefits seen at the site include accurate and timely process data logging for in-depth analysis, integrated safety features to contain potentially hazardous gas combinations and scalable and wide-ranging control system architecture to support future developments.
The GTL process developed by Aberdeen-based, Gas2 Limited – a gas reforming technology company – aims to convert natural gas to liquid hydrocarbon more economically and cleanly.
While proven at a laboratory level, the process required further robust examination within an up-scaled pilot plant environment to test and confirm its anticipated operational and capital investment benefits when compared to existing GTL technologies.
Siemens solution partner, Cordell Group Ltd worked alongside Siemens to install the pilot plant solution and support the next stage of development for Gas2.
The novel process takes place by separately pre-heating methane and oxygen under high pressure and injecting these into the reactor train. The raw materials are then reacted through the first stage to produce an exothermic process which raises the flow to a very high temperature. A second stage process then pre-heats the previously cooled syngas output under high pressure and injects these into multiple twin core reactors.
The syngas is then reacted to result in a variable process requiring rapid response within a temperature control system to maintain the flow in an isothermal, high temperature state.
Scaling-up from a laboratory level to pilot plant meant careful consideration had to be given to the safe handling of potentially hazardous gas combinations at high temperature and pressure. For this reason, Safety Integrated built into the SIMATIC PCS 7 control system using the Safety Matrix tool was specified and has provided a safe operating environment within which to develop the pilot plant.
As important has been the ability to extract, log and access the vast amounts of data generated by the process. Retrieving the operating process data is a critical element in the pilot plant’s operation as it enables Gas2 personnel to interrogate the findings and assess the progress of the technology without delay. As part of this process, the Siemens Process Historian acts as an essential tool, providing long-term data logging and archiving solutions.
Steve Leech, Business Manager - Process Control Systems at Siemens UK & Ireland, says: “As well as the safety driven benefits and the data handling capabilities, the SIMATIC PCS 7 control system allows for true scalability to match the requirements of Gas2. Its modular integrated strategic approach simplifies this and has helped in many areas, for example, providing the ability to collate process data from plant instrumentation often located some distance away via remote I/O stations.”
Dr Barry Mckenzie, Senior Operations Engineer at Gas2 adds: “The development of any new technology and the need to commercially and operationally prove the viability of the new approach is often a challenge when striving to drive innovation. So we’re pleased the benefits of scalable process system control, data intelligence access and safe operation offered by SIMATIC PCS 7 within the pilot plant, are now supporting us as we take the next step towards the commercial and technical success of our unique next generation gas to liquid technology.”