Design And Application Of LNG Integration Control System

With the rapid growth of energy demand, natural gas will be liquefied natural gas upstream and downstream integration system in the core component. LNG station with a large number of temperature, pressure, control valve, level control is be of structural complexity, and the system is running flexible way, because the inherent characteristics of liquefied natural gas and potential dangers of the LNG terminal control system has set higher Requirements. At present, security and stability control devices has become a safe and reliable operation of the essential means for liquefied natural gas. With computer technology in the industrial application of in-depth, comprehensive security and stability of liquefied natural gas control system of research and development has been rapid development and wide application.Based on the development of traditional integrated control, DCS system utilizing distributed system architecture distributes various tasks to each node and risk diversification along with higher reliability is achieved. Meanwhile, the response speed and the ability to handle complex issues of the system are greatly enhanced. DCS system in LNG station should possess higher reliability and system capability as strong as possible, including the function of data collection, security monitoring, adjustable control, auto-diagnosis capability, monitor alarming against the combustible leaking gas within the production zone etc. In order to ensure the reliability of the system, Station Control System should possess strong self-support ability to run while accepting monitoring from the dispatch center.Combined with actual project, the paper chooses the pre-process flow and the pretreatment according to the analysis of local condition temperature. The system utilizes the pressure difference and temperature difference control and responds quickly accordingly. Considering the characteristics of high pressure, low temperature, high risks and control delay for liquefied natural gas monitoring system, DCS system module control is utilized. Through operating directly by control interface, the monitoring and operation management of whole area of liquefied natural gas station can be accomplished. Reliability and security of system are laid more emphasis on the basis of analyzing the whole system's process security and production demand. Considering the product's best cost-effective factor, DCS system produced by HUA KONG, which adopts redundancy technique and provides high reliability, is chosen. Any component failure will not affect the whole system operation. As for the security of liquefied natural gas system, the DCS system also can advance several safety measures. Industry automatic monitoring software, which developed by SHI JI XING and provided clear and friendly human-machine interface, facilitates many aspects, such as security, advanced, reliability, redundancy, modular, expansibility, operability and maintainability can be reflected sufficiently in DING JIA liquefied natural gas station.Through long-term stable operation, DING JIA liquefied natural gas stationintegrated control system meets the requirements fully and posses safety, reliabilityand advanced characteristics.