Development of CFBC concepts and problem solution with the aid of simulation programs

Transcription

1 Development of CFBC concepts and problem solution with the aid of simulation programs CFB Workshop , Jyväskylä Hannu Mikkonen, VTT Technical Research Centre of Finland

2 2 Why to invest for modelling? Support for boiler investment plans Increasing of plant efficiency Decreasing of operating costs Optimization of the boiler life time Education by using process simulator Where does the modelling is used for? An environment for process simulation models building. Evaluation of process phenomena and problems Optimize production Use as a training simulator Design and testing environment

3 3 Process simulation Design Engineers Simulation and process design integration Simulation Engineers Process design Automation design 3D design Common user interface environment Apros Process Simulation Other simulators: Balas, DEVS, sd, Fluent, Modelica, company specific Plant design systems: SmartPlant Foundation, Comos, Engineering Information Management Simantics Simulation Information Management

4 4 The automation can be included in the model... Control circuits Logic circuits Sequences Change-over automation Control system model Dynamic process simulation Set points Process model Integrated process level Process component level Measurements Or real/virtual automation application can be connected to the process model. Position Device controls Actuators Basic component level Elementary components branches, nodes, structures, sources Conservation equations for mass, momentum and energy

5 5 Apros modelling program The Apros provides easy on-line access for: o configuring and running the simulation models o solution algorithms and model libraries for full-scale modelling o dynamic simulation of processes, such as conventional power plants, nuclear power plants, and pulp and paper mills. The model libraries have been comprehensively validated against data from physical process experiments. Besides the process, also automation and electrical systems can be modelled in detail. The simulation environment aims at meeting the requirements for testing, design, analysis, and training simulator applications

6 LIME Q= Q= Q= Q= Q= Q= Hier arc hy W= S Q= Hierarch y W Hierarch y 02/10/ Aspen Plus - modelling program Aspen Plus and Dynamics are focused on process engineering and optimization. Optimize process designs for energy use, capital and operating costs, and product yield through the use of activated energy, economics, and equipment design during the modeling process. Due the different features of Apros and Aspen VTT uses both platforms to model large complex processes. BOILER HP-Intrex 4 HP-Intrex 3 Spraying 2 Superheater 2 Spraying 1 Reheating Superheater 1 H TURBINE Lime feed Fuel feed Cross over duct and Convection cage HP-turbine IP-turbine LP-turbine Total electric power Condensation tank Furnace O2 H Eco HP-Preheating Feedwater pump Feedwater tank LP-Preheating

7 7 An example of a modelled case: Coal plant evaporator analysis Target: 315 MW pulverized coal power plant of Fortum, located in Naantali, Finland. Origin in the 1970 s. Motivation: Suffered of evaporator tube damages. Recent change in control strategy. Does the new way increase risk for tube ruptures? Approach in modelling: detailed model of the evaporator tubes, minimum scope of the surrounding process, rough model of the combustion heat power Analysis of the temperatures of the individual tubes when different operational scenarios are practised Ref: Lappalainen, J., Blom, H, Juslin, K., Dynamic process simulation as an engineering tool A case of analysing a coal plant evaporator, VGB Powertech, 1/2 2012, pp

8 8 Combination of Apros and Aspen models APROS SIMULINK CFB boiler Turbine and water circulation ASPEN PLUS DYNAMICS Oxygen production plant CO2 pressurizing and separation

9 Simulation examples (Apros) Load change: oxygen 100% - 40% - 100% Mode change: air oxygen - air 80 Flue gas CO2 22 Flue gas H2O mol% mol% Time, s Time, s 6 Flue gas O2 80 Flue gas N mol% 3 mol% Time, s Time, s

10 10 Conclusion VTT has powerful modelling tools for researching, analysing, design, testing and education. Apros is capable to dynamic evaluation of large process areas. Aspen Plus is capable to steady state studies and is powerful tool for chemical process evaluations. At VTT there are made several years process modelling in different kind of projects Modelling projects on-going at VTT: - Apros furnace model development - Boiler and CCS-process heat integrations - Combined use of the solar field power and boiler - Controlling of the whole concept including process and control development

11 VTT 2014