Design And Research On Pilot-scale Industrial Supercharged Boiler

Supercharged boilers burning air in the furnace which its pressure is 0.2~0.4 MPa,to enhance the combustion.Compared with normal industrial boilers,its pressure is higher,but with lighter weight,smaller size,higher reliability and better economic efficiency.It mainly used for power systems of large ships.However,when supercharged boilers start up,it need to promote the auxiliary steam turbine and drive compressor through the reducer,thus resulting in system to be more complex and expensive.Therefore,limited the industrial application of supercharged boiler.Under this background,this paper put forward researching and development of new industrial supercharged boiler,intends to adopt roots blower and small turbocharger widely used in vehicles,ships,engineering machinery.Combustion air supplied by roots blower,exhaust gas promote turbine to work,then drive compressor provides pressurized air and achieve the start-up of supercharged boiler at low load.This scheme reduce the cost of system,and once it is feasible,will greatly promote the application of industrial supercharged boiler.But the start-up of small turbocharger and its matching with roots blower or supercharged boiler are key issues whether the scheme can be implemented.There are few studies currently.In this paper intend to design a new type of pilot-scale industrial boiler based on the new principle.The pilot-scale boiler is mainly used for verify feasibility of roots blower start scheme,work matching and experimental study between turbocharger and pilot-scale boiler.The design of pilot-scale boiler is divided into two parts: mechanical equipment,measurement and control system.When design mechanical equipment,the flow between import and export has conform to flow conservation,also the boiler must meet the conservation of energy.First completed thermal calculation of entire pilot-scale boiler,then selected turbocharger,finished design and manufacturing of burner and furnace,as well as roots blower selection.When design measurement and control system,determined the control process in order to meet test requirements,designed basic structure of PLC programs andsystems of control.Then determined the components and equipment of the signal acquisition system.Finally,debugged the pilot-scale boiler,the experiment results show it works well,and turbocharger run smoothly with pilot-scale boiler.In this paper,a roots blower replace auxiliary turbine to start pilot-scale supercharged boiler,and verify the start-up.This scheme needn’t to arranged steam reservoir and complex steam pipeline,saving cost,and is suitable for complex conditions.A small turbocharger widely used in vehicle and engineering machinery was adopted and through the pilot-scale boiler demonstrated the turbocharger works well with the boiler,provide a reference for the research and development of new industrial supercharged boiler,lay the foundation for the promotion of the supercharged boiler,has certain innovation significance.