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Part 1 of the Report on Coal-to-Oil Production: Overview of Centralized Control in Coal-to-Oil Processes. The control rooms for Shenhua’s coal-to-oil facilities are located in separate locations; the control systems operate in a decentralized manner, with each unit being controlled independently, and there is no data communication between them. In the scheduling system for the upper network layer, there is only one data server, which enables data monitoring of all workstations in the entire plant; the scheduling function is carried out through telephones. The original control approach for coal-to-oil production was the same as ours today: a centralized control system was used, with a central control room while the control cabinets were located at various sites. However, since interference between units is inevitable during testing, control rooms (13 in total) were arranged separately by work section, and the control room textile cabinets were designed to facilitate debugging and troubleshooting. Its data communication method is primarily MODEBUS, with hardwired connections available in two types: 24VDC and 220VAC. The plant’s control systems include DCS, ITCC, and PLC. DCS is Honeywell’s PKS system, ITCC is the TRICON system, and PLCs are provided by Siemens for complete equipment sets. The PLC system merely stores the control programs; although there is an operation station, it is only used for monitoring, while operations are carried out on the DCS (which results in the use of two systems for the process, representing some waste). PLC and DCS communication uses RS485. The ESD systems are also installed separately at individual units, with no interlocking between them. The ESD system uses TRICINEX, the most reliable product from TRICON. The control system configuration of the entire plant is as follows: Scheduling system, DCS system, ITCC system, TPS, RTU, PLC, ESD, and field equipment. Part II: Examination of the air separation unit control system. The coal-to-oil air separation units use the Linde process, with two units capable of producing 50,000 HM3/h of oxygen. The main control systems include two ITCC systems (CONSEN) and two DCS systems (PKS). The control station is configured with 4 DCS units for the air separation process, 2 ITCC monitoring control stations, and 2 circulating water control stations (DCS). The control room is also equipped with auxiliary control panels (for emergency shutdown and alarms), alarms, and other devices. The engineer station is equipped with two DCS engineer stations (servers that serve as backups to each other, allowing for seamless switching) and one ITCC operation station. The FLEX STATION is selected for the operation station; this means that the operation station must be connected to the control station via a server, in order to reduce the communication load on the main control card. The control content is as follows. The main control functions of the ITCC include: anti-surge control for air compressors, anti-surge control for the intermediate and final stages of boosters, anti-surge control for expanders, unit loading control, turbine speed regulation control, and the crankshaft turning system. Among them, the turbine overspeed protection is achieved through a two-out-of-three voting system using the on-site overspeed protectors. The unit’s detection and protection system does not utilize the 3500 system; instead, all sensors have their signals converted through BENTLY3500 gap amplifiers to enable unit protection. The main control aspects of DCS include: air cooling system, purification system, condensate system, main coolant level control, liquid oxygen pump control, etc. The communication between the ITCC and the DCS uses both RS485 and hardwired connections (RS485 for data monitoring, while hardwired connections are used for control interlock signals). RS485 communication also comes in two types (with different hardware configurations); one type uses a server to convert the two-wire system into TCP/IP protocol data, which is then transmitted to the main control card via a switch (this allows for configuration within the DCS framework and reduces the load on the I/O LINK) ； Another option is to directly feed two-wire data into the DCS cards (this ensures reliable data transmission). The unit uses MAN’s turbines and air compressors as well as boosters, while the expanders are from a French manufacturer. The configuration was completed by engineers in Germany; the protection system is reliable and the operation interface is excellent (photos have been taken), which can serve as a reference for us. Based on the configuration details and screen display, the control functions of ITCC are quite comprehensive. In particular, the allocation of control tasks between ITCC and DCS is reasonable, and the screens are clean and clear, facilitating operation and monitoring. There are 15 electrical and instrumentation maintenance personnel for air separation, and their process flow is basically the same as that provided by our Hangyang company. Images captured: Another area where its air separation system can serve as a model is the use of monitoring screens in the control room to oversee dangerous equipment and sections such as the oxygen supply valves and storage tanks on site. Part Three: Report on the simulation system. The coal-to-oil simulation system only includes its core unit – coal liquefaction – and it was used solely for training during trial operations; by the time we arrived, it had already been sealed, so we were not able to see the actual version of this simulation system. However, through communication with skilled process engineers and our connections with simulation system manufacturers, we have gained a very detailed understanding of the simulation systems. Furthermore, we have obtained from the manufacturer the software for the simulation system as well as simple configuration demonstration files, to help us gain a better understanding of it. 1. Concept of simulation systems: Simulation technology is closely related to computer technology. It is a multidisciplinary integrated technology that relies on theories such as similarity theory and model theory, system technology, information technology, as well as various specialized techniques from the field of simulation applications. It uses computer systems, devices that simulate physical effects related to specific applications, and simulators as tools, and employs model systems (actual or hypothetical) for research. Simulation systems are classified into different industries depending on the sectors they serve, such as aerospace, nuclear power generation, thermal power generation, petrochemicals, metallurgy, and light industry. The petrochemical simulation system was developed and applied abroad starting from the late 1960s, following aerospace and power plant simulation systems. It is a comprehensive practical technology based on disciplines such as chemical engineering, computer technology, control engineering, and systems engineering. A petrochemical simulation system is based on computer hardware and software technologies. By gaining a thorough understanding of various petrochemical processes, equipment, control systems, and their operational procedures, dynamic mathematical models of these processes and equipment are developed and turned into software. Additionally, various training functions that can be easily implemented on computers but are not possible in traditional teaching and practice are designed, creating a training environment that closely resembles actual production conditions. This allows personnel involved in petrochemical production processes to carry out operations and experiments using such simulation systems. The policy manufacturers I am in contact with at present include: Yokogawa of Japan, Beijing Huakangda, Beijing Dongfang, and Zhejiang University Zhongkong. Based on the product information provided by the manufacturer, the main overview and comparisons are as follows: 2. Hardware system configuration and scale: Foreign simulation systems typically use workstations/PCs as instructor stations and engineer stations, while the student operation stations consist of actual DCS stations (usually 3–6 operation stations); generally, they operate in a manner similar to that of a control room ； The simulation system developed domestically uses PCs as the teacher station and engineer station, as well as PC-based simulated DCS stations. Comparing the two: the hardware investment for simulation systems in China is significantly lower. More importantly, OTS systems in China place more emphasis on organizing teaching and training; as a result, they usually offer both a single-machine operation mode and a multi-machine training mode with free grouping, to facilitate the organization and management of teaching processes. 3. Functions implemented by the simulation system: In terms of the standard functions of chemical engineering simulation systems, the functions provided by domestic systems are now on par with those of advanced foreign systems. However, the “skill assessment function” of domestic simulation systems (which is not a simple scoring function) is a major feature of them, one that foreign simulation systems do not possess. The main reason is that the application scope of simulation systems abroad does not include the assessment of operators’ skills. 4. Development methods for simulation systems: The development approaches and methods used in petrochemical simulation systems both domestically and internationally are exactly the same. The difference is that advanced foreign simulation systems use graphical development tools to create the integration of process unit models, while in China, a combination of form filling and graphics is used for such integration. Relatively speaking, the development environments for simulation systems abroad are more in line with the prevailing trends in software development and are more convenient. 5. Investment in simulation systems: There is a significant difference between domestic and foreign companies in terms of investment in simulation systems. With the same hardware configuration, the investment required for simulation systems in China can be significantly reduced, making them particularly suitable for the investment capabilities of users in that country. Investments in software system development are much lower in domestic companies compared to those in foreign companies. The costs of installation, commissioning, and maintenance are also incomparable to those of foreign companies. After communicating with the simulation manufacturers, reports have been received from Dongfang and Yokogawa: Dongfang: Device name, User’s process, Patent handling capacity, DCS type. Gasification – Lunan Fertilizer Plant, four-nozzle type (Texaco improved), 200,000 tons of methanol; Zhejiang University Zhongkong, Yankuang Guotai, four-nozzle type (Texaco improved), 240,000 tons of methanol; CS3000, Xinjiang Guanghui Lurgi, 1.2 million tons of methanol; ABB 800f, purification – low-temperature methanol washing; Hubei Petrochemical, Linde, 300,000 tons of synthetic ammonia; CS3000, Xinjiang Guanghui Lurgi, 1.2 million tons of methanol; ABB 800f, Anqing Petrochemical, Linde, 300,000 tons of synthetic ammonia; TPS methanol synthesis, Lanzhou Lanxing Lurgi, 200,000 tons per year; CS3000, Xinjiang Guanghui Casali, 1.2 million tons per year; ABB 800f, Qilu Petrochemical Lurgi, 100,000 tons per year; CS3000, ethylene production, Lanzhou Petrochemical, KBR, 600,000 tons per year; Deltav, Daqing Petrochemical (old), SW, 350,000 tons per year; CS3000, Jilin Petrochemical, LINDE, 600,000 tons per year; TDC3000, Daqing Petrochemical (new), SW+B&R, 350,000 tons per year; CS3000, Zhenhai Refining & Chemical, LUMMUS, 1 million tons per year; PKS, polypropylene (PP), Shanghai Petrochemical, Sinopec (BEPC), 300,000 tons per year; TPS, Lanzhou Petrochemical, Basell, 300,000 tons per year; Deltav, Dalian Petrochemical, Basell, 200,000 tons per year; TPS, Dagang Oilfield, Basell, 100,000 tons per year; CS3000, Tianjin Petrochemical, Basell (gas/liquid), 450,000 tons per year; CS3000, Zhenhai Refining & Chemical, Sinopec (BEPS), 450,000 tons per year; PKS, polyethylene (PE), Dushanzi Petrochemical, BP (gas phase), 120,000 tons per year; TDC3000, Lanzhou Petrochemical, UCC UNIPOL, 300,000 tons per year; Deltav, Jilin Petrochemical, SD (reactor type), 300,000 tons per year; CS3000, Daqing Petrochemical, Basell (high pressure), 200,000 tons per year; TPS, Yangzi Petrochemical, UCC UNIPOL, 200,000 tons per year; TPS, Zhenhai Refining & Chemical, UCC UNIPOL, 300,000 tons per year; PKS. Yokogawa: Serial number, Province/Region, User’s name, Device name, Delivery date. 1. Hebei, Langfang, New Energy Group Co., Ltd., 600,000 tons of methanol, April 2008. 2. Shandong, Shandong Jiatai Petrochemical, 2,500 Nm3/h methanol cracking hydrogen production unit, November 2007. 3. Yunnan, Yunwei Group Co., Ltd., 200,000 tons per year of methanol to acetic acid, November 2007. 4. Shanxi, Shanxi Coking Co., Ltd., 200,000 tons per year of methanol, July 2007. 5. Xinjiang, Xinjiang Petroleum Administration Methanol Plant, expansion of methanol production capacity to 250,000 tons per year, July 2007. 6. Inner Mongolia, Qinghua Group Qinghua Coal Chemical Co., Ltd., 200,000 tons per year of methanol, June 2007. 7. Sichuan, Sichuan Jianzhong Xingyu Chemical Co., Ltd., 50,000 tons of methanol, October 2006. 8. Nanjing Huisheng, Nanjing Chemical Co., Ltd., methanol/CO2, September 2006. 9. Chongqing, Chongqing Jiantao Natural Gas Chemical Co., Ltd., 450,000 tons per year of methanol, September 2006. 10. Xinjiang, Xinjiang Petroleum Administration Methanol Department, 200,000 tons per year of methanol, August 2005. 11. Shaanxi, Yulin Natural Gas Chemical Co., Ltd., methanol storage tank area, April 2005. 12. Sichuan, Lutianhua Lvyuan Alcohol Co., Ltd., methanol/air separation, August 2004. 13. Shaanxi, Weihe Clean Energy Coal Chemical Co., Ltd., 28 KM3/H oxygen production, 150,000 tons per year of methanol, August 2004. 14. Shaanxi, Yulin Natural Gas Chemical Co., Ltd., 200,000 tons per year of methanol, August 2004. 15. Xinjiang, Xinjiang Petroleum Administration Dushanzi Petrochemical Complex, 30 Kt/d methanol production unit, May 2004. 16. Nanjing, Nanjing Chemical Company Nitrogen Fertilizer Plant, methanol modification, August 1996. 17. Shaanxi, Yulin Natural Gas Chemical Plant, 60,000 tons per year of methanol, June 1996. 18. Shanxi, Taiyuan Chemical Plant, methanol, June 1993. 1. Shanghai, Shenhua Group, Shanghai Coal Liquefaction Demonstration Unit, coal liquefaction demonstration unit, May 2004. 2. Shaanxi, Shaanxi Xinxing Coal Chemical Technology Development Co., Ltd., coal-to-olefins, July 2005. 3. Yunnan, Yunwei Group Dada Ammonia Production Co., Ltd., 500,000 tons per year of synthetic ammonia, December 2006. 4. Guizhou, Guizhou Xingsheng Coal Chemical Co., Ltd., coal-based gasification alternative fuel project, February 2009. 5. Guizhou, Guizhou Jinchi Chemical Co., Ltd., Tongzi coal chemical project, April 2009. Hardware structure of the simulation system: After understanding it, I feel that the utilization rate of the coal-to-oil simulation system is not high, which results in wasted functionality of the system. After comparing the performance of the four manufacturers, and considering that the methanation project is the one most likely to utilize a simulation system for our project, I found that only Huakangda had carried out simulation work on an alkylation system in Mexico in 2006. Part Four: Establishment of the Central Control Management System. Developing a scientific, rational, and strict central control system can provide a favorable environment for the safe operation of centralized control systems; it is a system that we must establish. The system for coal-to-oil conversion can be considered to be well-established, but the enforcement is insufficient; therefore, we should take this as a lesson.