3MW Oxyfuel Combustion Pilot System Control Strategies Study

At present the large-scale use of fossil energy, results in that the global CO₂emissions and its concentration in air has been increasing year by year. Since the scaleof CO₂is very big, its greenhouse effect is the strongest among the GHGs（Greenhouse gas）. Many developed and developing countries, according to theirrespective national conditions, formulate the effective control measures policies andgoals to reduce CO₂emissions to slow down the greenhouse effect intensifying.China actively promotes fossil energy clean development, protects the ecologicalenvironment, copes with the climate change, achieves energy conservation andemission reduction, supports the development of carbon capture and storage bytechnology application demonstration projects, etc.3MW Oxyfuel combustion pilotsystem is a large-scale early industrial demonstration technological verificationplatform, which is used to test and verify the key technologies of oxyfuel combustionfor carrying out system integration and process optimization.Based on3MW oxyfuel combustion pilot plant and according to the controlperformance requirements of the system and test, put forward the correspondingcontrol strategy for the implementation of system normal and stable operation and testthe special requirements.The paper first introduces the differences of the heat transfer between aircombustion and oxyfuel combustion, and then, according to the characteristics ofoxyfuel combustion and the need to introduce the control strategy, puts forward theconcept of the total oxygen concentration. Through qualitative analysis of the oxyfuelcombustion test data, understand the dynamic characteristics of the object, whichwould provide the reference for the control strategy.Then, according to the system and test requirements, puts forward part of thecontrol strategy, which includes （1） double closed loop variable proportional controlsystem for the flow control of hybrid wind and ASU oxygen;（2） ASU oxygen flow cascade control system for the furnace outlet oxygen concentration control;（3） aircombustion and oxyfuel combustion mutual switch control strategy;（4）dry and wetmixing cycle control system, etc.