Foreword

Li Zheng Lai Technology focuses on the digital transformation of sulfuric acid plants and is committed to promoting the full automation of sulfuric acid plants. In the sulfuric acid industry, automation has become a hot topic, but there is no unified standard for the function of sulfuric acid plant automation. When consulting and implementing sulfuric acid plant automation upgrades, we found that different users have different understanding of automation goals. In general, sulfuric acid plant automation is understood to achieve the three major goals of zero manual operation, autonomous operation and black screen operation. The core concept of these goals is to ensure that sulfuric acid plants are produced automatically without human intervention during the production process. However, the full life cycle of a sulphuric acid plant includes not only the production process, but also the automation of safety before start-up, the automation of start-up processes, the automation of operating processes, the automation of load adjustment, the automation of emergency response and the automation of plant health monitoring. Therefore, to achieve automation in these six aspects, the sulfuric acid industry needs to gradually promote technology research and development.

With the continuous progress of technology, the automation of sulfuric acid equipment is developing in the direction of intelligence and unmanned. Through the application of artificial intelligence and digital technologies, the health of the device and the production process will become more transparent, efficient and safe. Going forward, sulfuric acid plants will be able to adapt more rapidly to social, economic and technological changes. Based on the rapid development of current technology, Eli Lilly has divided the automation of sulfuric acid plants into four levels in technology research and development: Level L1 basic automation, level L2 conditional automation, level L3 advanced automation and level L4 digital automation.

One, L1 basic automation

A unit is operated by 4 to 5 production operators per shift, mainly through the DCS control system to monitor and control the production process. The control system can adapt to the disturbance of individual process parameters of the device and automatically adjust it. At the same time, it can perform basic remote manual switching control and parameter adjustment. Changes in process parameters during production trigger automatic alarms, but there are potential failures in the unit that require experienced engineers to detect. Load adjustment requires the operator to operate and adjust multiple process parameters of the device. When the process parameters of the device are disturbed by external disturbances, the operator needs to intervene in time to prevent accidents. In the process of opening and stopping the device, the operator needs to check each item and take DCS remote operation. However, the completion of the production task and safety inspection of the device depends on the commitment of the operator.

Second, L2 level conditional automation

A unit is usually operated by 3 to 4 production operators. Although the sulphuric acid plant is able to keep the load stable and automatically control the process parameters without operator intervention, it is also equipped with early warning systems such as safety interlocks and efficient alarms to ensure that operators are not on-site during start-up and shutdown, as well as during operation. However, before driving, the operator must conduct a safety check; In the process of driving, the operator needs to operate the whole process; When the load of the plant changes, the operator must step in and monitor the process control parameters to ensure that they are safe and controllable. After stopping, the operator needs to confirm the safety status of the device one by one. Operators also need to be ready to take over control throughout the production process and participate in production and safety inspections throughout the process.

Three, L3 advanced automation

A set of equipment is operated by 1 to 2 production operators per shift, and the auxiliary monitoring device realizes the automation of operation, covering the automation of safety before starting, the automation of driving process, the automation of running process and the automation of load adjustment. However, the operator still needs to intervene in the event of an unexpected situation or device fault diagnosis.

Four, L4 digital automation

The ultimate goal of automated production of sulfuric acid plants is to ensure the health of the plant and the transparency of the production process throughout the life cycle through the application of unified digital technology. When any production requirement arises, the unit should be able to perform the task completely autonomously, without operator intervention, even in the case of emergency or complex fault diagnosis. In theory, L4 digital automation represents the ideal level of automation for sulphuric acid plants, however, there are still technical and regulatory challenges to its practical application.

Five, the future development trend

With the growing demand for zero manual operation, autonomous operation and black screen operation technology proposed by the whole industry for sulfuric acid plant, combined with our awareness of the need for sulfuric acid plant automation in the implementation process, automatic control, virtual reality simulation, AI analysis and data analysis technology are adopted. It can realize safety automation before driving, automation of driving process, automation and optimization of production process. These technologies enable real-time adjustment of production parameters to ensure that the process is always close to design standards. Through virtual reality simulation and data analysis, we are able to predict and maintain the health status of the plant and equipment in a timely manner to ensure the long-term continuous production of the sulfuric acid plant. With the wide application of these technologies, we have achieved the technical ecology of level 4 digital automation. Level L4 digital automation does not mean complete unmanned, but changes the structure of the current production staffing of sulfuric acid plants. In the sulfuric acid production process, no direct operator intervention is required, but a small number of professionals are required to use digital sulfuric acid systems to monitor the health of the plant and to schedule production in the relevant industrial chain.