Modeling Solids Dryers and Granulators with Aspen Plus V8

Transcription

1 Modeling Solids Dryers and Granulators with Aspen Plus V8 Ajay Lakshmanan and Claus Reimers Product Management, AspenTech Hosted by: Julie Levine and Ron Beck, Product Marketing, AspenTech Solids Process Modeling Webinar April 16, Aspen Aspen Technology, Inc. Inc. All All rights rights reserved 1

2 Ongoing Series of Technical Webinars Engineering webinars for education and best practices RECENT WEBINARS: Model Solids Processes Easily with Aspen Plus (Technical) Case Study: Maximizing Energy Efficiency with Maturus Optimi UPCOMING WEBINARS OF INTEREST: Compressor Modeling using Aspen HYSYS Dynamics (Technical) April 23 rd Utilizing Property Data with Aspen Properties in Aspen Plus (Technical) May 15 th ALSO UPCOMING: OPTIMIZE 2013 Global Conference May 6 th -8 th 2013 Aspen Technology, Inc. All rights reserved 2

3 aspenone Engineering Best-in-class engineering solutions in an integrated workflow Common Models & Data Support Manufacturing & Supply Chain Aspen Simulation Workbook & Aspen Online Deployment Aspen Petroleum Downstream & HYSYS Upstream Conceptual Engineering Aspen Plus Dynamics, ACM & Flare System & Energy Analyzer Aspen Plus Aspen HYSYS Aspen Process Economic Analyzer (APEA) Basic Engineering Aspen Equipment Design & Rating Aspen Basic Engineering Aspen Capital Cost Estimator (ACCE) Detailed Engineering Detailed Engineering aspenone Integration 2013 Aspen Technology, Inc. All rights reserved 3

4 Agenda Introduction Convective Drying Demonstration 1 Belt and Fluidized Bed Drying Granulation Demonstration 2 Granulation and Agglomeration Questions & Discussion 2013 Aspen Technology, Inc. All rights reserved 4

5 Why is Solids Modeling Important? Specialty & Agricultural Chemical Process Fertilizers, ChlorAlkali, pta, Silicones Fluid Raw Material Reactions (liquid/gas) Separation (liquid/gas) Crystallization (liquid/solid) Drying (solids/gas) Solid Product Fluids Solids + Fluids Extractive Industry Process Coal, Oil Sands, Cement, Phosphates, Alumina Mineral Raw Material Grinding (solids) Classifying (fluid/solid) Reactions (fluid/solid) Separation (solids/liquid /gas) Fluid Products Solids + Fluids Solids + Fluids 2013 Aspen Technology, Inc. All rights reserved 5

6 Modeling Processes with Solids Traditional Approach Aspen Plus Urea Synthesis Model SolidSim Urea Granulation Model Two Models Manual Data Transfer Inconsistent Properties Local Optimization 2013 Aspen Technology, Inc. All rights reserved 6

7 AspenTech and SolidSim Bringing Our Strengths Together Physical Properties Reactions & Electrolytes Fluid Unit Operations Integrated Workflows Worldwide Support University Program Solids Process Modeling Solids Characterization Solids Unit Operations Deep Expertise Relationship with universities researching solids technology 2013 Aspen Technology, Inc. All rights reserved 7

8 Aspen Plus V8.0 Optimizing Processes with Solids Made Easy Sample Templates Online Training Visualize PSD Optimize Entire Process 10 Unit Operations 2013 Aspen Technology, Inc. All rights reserved 8

9 Agenda Introduction Convective Drying Demonstration 1 Belt and Fluidized Bed Drying Granulation Demonstration 2 Granulation and Agglomeration Questions & Discussion 2013 Aspen Technology, Inc. All rights reserved 9

10 Why is Convective Drying Important? Problem: High Energy Consumption Benefit: Optimizing design and operation reduces energy use by 25-30% 2013 Aspen Technology, Inc. All rights reserved 10

11 Convective Drying Drying Curves 11 Drying periods Initial period Heat the wet solids Constant rate period 1 st Drying period Dry moisture on surface Moisture content above critical moisture content Falling rate period 2 nd Drying period Dry moisture inside particles Moisture content below critical moisture content and above equilibrium moisture content Ends at equilibrium moisture content 2013 Aspen Technology, Inc. All rights reserved 11

12 Convective Drying Model Description Flow patterns Co-current Counter-current Cross-current Solids in plug flow in axial, ideally mixed in lateral direction, gas in plug flow Solids ideally mixed, gas in plug flow Drying model Based on drying kinetics Normalized drying curve describes falling rate drying Mass transfer coefficient between particles and gas: Sherwood number Mass transfer coefficient Product of mass transfer coefficient and surface area Number of Transfer Units Heat Transfer Coefficient user defined or calculated 2013 Aspen Technology, Inc. All rights reserved 12

13 Normalized Drying Curve Normalized drying curve describes the falling rate period Normalized drying rate Normalized moisture content current dryingrate v( ) st drying rate1 drying period X X cr X X eq eq X: Current moisture content X cr : Critical moisture content X eq : Equilibrium moisture content Normalization 2013 Aspen Technology, Inc. All rights reserved 13

14 How is the Normalized Drying Curve Determined from Measured Data? The normalized drying curve is typically derived from experiment data 2013 Aspen Technology, Inc. All rights reserved 14

15 How is the Normalized Drying Curve Determined from Measured Data? Step 1: Determine critical moisture content, equilibrium moisture content Current case Critical moisture content: X crit = 0.1 kg/kg Equilibrium moisture content: X equi = kg/kg 2013 Aspen Technology, Inc. All rights reserved 15

16 How is the Normalized Drying Curve Determined from Measured Data? Step 2: Calculate the drying rate and determine the drying rate at the 1 st drying period Current case Constant drying rate: M I = 1.65 g/(kg*s) 2013 Aspen Technology, Inc. All rights reserved 16

17 How is the Normalized Drying Curve Determined from Measured Data? Step 3: Calculate normalized drying rate and normalized moisture content current dryingrate v( ) st drying rate1 drying period X X cr X X eq eq Critical moisture content: X crit = 0.1 kg/kg Equilibrium moisture content: X equi = kg/kg 2013 Aspen Technology, Inc. All rights reserved 17

18 Convective Dryer Forms Drying Curve Tab Define normalized drying curve via tabular data or use of a function 18 Define critical and equilibrium moisture content Normalized moisture content Normalized drying rate 2013 Aspen Technology, Inc. All rights reserved 18

19 Agenda Introduction Convective Drying Demonstration 1 Belt and Fluidized Bed Drying Granulation Demonstration 2 Granulation and Agglomeration Questions & Discussion 2013 Aspen Technology, Inc. All rights reserved 19

20 Convective Drying Fluidized Bed Dryer The following example will demonstrate how a multi-chamber fluidized bed dryer could be modeled with Aspen Plus Live Demo 2013 Aspen Technology, Inc. All rights reserved 20

21 Convective Drying Fluidized Bed Dryer Summary Aspen Plus can be used to model fluidized bed dryers with multiple drying chambers Beside the drying of the material also entrainment and gas-solid separation can be considered in an Aspen Plus model Model shows the behavior of the overall drying process Temperatures Moistures Flow rates Particle size distributions Model gives information's about the internal streams in the dryer that normally could not be measured 2013 Aspen Technology, Inc. All rights reserved 21

22 Convective Drying Belt Dryer The following example will demonstrate how a Belt Dryer could be modeled and optimized with Aspen Plus Modeling of a complex apparatus Several drying zones with profiles of air recirculation and temperature along the dryer Cooling zone with heat recovery preheated make-up air Humid exhaust air ambient air zone 1 zone 2 zone zone zone cooling zone 2013 Aspen Technology, Inc. All rights reserved 22

23 Convective Drying Belt Dryer Drying of Solids Solids are dried from ~261 g/kg dry to less than 11 g/kg dry by use of a 4 chamber belt dryer with internal air recirculation In the current setup the dryer has an energy consumption of 561 KW-Hr/ton product approx. 93% of that heating energy is provided by the primary heater Objective: Reduce the energy demand of the dryer by at least 10% Constraints: Throughput should be unchanged (~ 2 t/h) Solids Temperature profile along the dryer should be mostly unchanged Product moisture should be less than 11 g/kg dry 2013 Aspen Technology, Inc. All rights reserved 23

24 Belt Dryer Demonstration Live Demo 2013 Aspen Technology, Inc. All rights reserved 24

25 Convective Drying Belt Dryer Summary Aspen Plus can be used to model Belt Dryers with multiple drying and cooling chambers Temperature and moisture profiles along the dryer can be calculated Model can be used to optimize the energy demand of an industrial Belt Dryer by Investigate the impact of cooling stages Determining optimal flow rates and temperature 2013 Aspen Technology, Inc. All rights reserved 25

26 Agenda Introduction Convective Drying Demonstration 1 Belt and Fluidized Bed Drying Granulation Demonstration 2 Granulation and Agglomeration Questions & Discussion 2013 Aspen Technology, Inc. All rights reserved 26

27 Why is Granulation Important? Problem: Product quality and process stability variability Benefit: Improve coating and product purity Increase throughput 2013 Aspen Technology, Inc. All rights reserved 27

28 Granulation Growth of particles due to deposition of solid material on primary particles (seeds) Granulation: Seed and deposited solids are the same material Coating: Seed and deposited solids are different materials 2013 Aspen Technology, Inc. All rights reserved 28

29 Agglomeration Agglomeration: Aggregation of two or more primary particles Agglomeration by use of a binder Binder could be water, a suspension, solution or melt Particles are glued together Agglomeration by use of mechanical forces No binder is added Particles are pressed together 2013 Aspen Technology, Inc. All rights reserved 29

30 Modeling Agglomeration and Granulation The Aspen Plus Granulator can be used for: Granulation and Coating Drum Fluidized Bed Plate Agglomeration using binder Drum Fluidized bed Plate using mechanical forces Compacting Press Roller Agglomerator 2013 Aspen Technology, Inc. All rights reserved 30

31 Granulation Model Particle Growth Population balance Mixed Ideal mixing in radial and axial direction Growth rate proportional to Surface, Volume or Diameter Plug flow Ideal mixing in radial direction No mixing in axial direction Drying of particles Define solids moisture content at the outlet Entrainment in Fluidized Beds Upstream gas velocity Terminal velocity of the particles 2013 Aspen Technology, Inc. All rights reserved 31

32 Agglomeration Model Particle Growth Population balance Growth rate described by kernels Time-dependent part b 0 (t) Parameterize using experimental data Flux number approach used for fluidized bed Size-dependent part b(u,v) Several models implemented Ideal mixing for radial and axial direction Pure binary agglomeration is assumed Drying of particles Define solids moisture content at outlet Entrainment in Fluidized Beds Upstream gas velocity Terminal velocity of the particles 2013 Aspen Technology, Inc. All rights reserved 32

33 Agenda Introduction Convective Drying Demonstration 1 Belt and Fluidized Bed Drying Granulation Demonstration 2 Granulation and Agglomeration Questions & Discussion 2013 Aspen Technology, Inc. All rights reserved 33

34 Agglomeration Example The following example will demonstrate how a fluidized bed agglomerator could be modeled with Aspen Plus Flux number approach is used to obtain the time part of the agglomeration kernel Live Demo 2013 Aspen Technology, Inc. All rights reserved 34

35 Agglomeration Summary Aspen Plus can be used to model fluidized bed agglomerators The use of the Flux number approach allows calculating the time-dependent part of the agglomeration kernel based on operating conditions Binder flow rate and superficial gas velocity have a direct influence on the product particle size distribution 2013 Aspen Technology, Inc. All rights reserved 35

36 Granulation Example The following example will demonstrate how a industrial granulation process can be simulated and optimized with Aspen Plus Simulation of a granulation process with external classification/grinding circuit and product cooling Optimization study to increase throughput Live Demo 2013 Aspen Technology, Inc. All rights reserved 36

37 Granulation Summary Aspen Plus can be used to model industrial granulation processes with external classification and grinding circuit Multi-chamber granulators can be described by use of a hierarchy block Information about internal streams can be obtained Model can be used to optimize the process with regard to Throughput Product quality 2013 Aspen Technology, Inc. All rights reserved 37

38 Agenda Introduction Convective Drying Demonstration 1 Belt and Fluidized Bed Drying Granulation Demonstration 2 Granulation and Agglomeration Questions & Discussion 2013 Aspen Technology, Inc. All rights reserved 38

39 Registration Discount for Webinar Attendees! $1,700 a savings of 15% off the standard conference fee! For more information, visit and use the promotional code APWEB2013 to receive the discount. Offer Expires April 22! OPTIMIZE May 2013 The Westin Waterfront Hotel Boston, MA USA 2013 Aspen Technology, Inc. All rights reserved 39

40 Optimize 2013 Global Conference May 6-8, 2013 Cansolv (Shell) Modeling of CO2 Capture with unique amine solvents Hitachi Zosen Ethanol distillation membrane separation model with Aspen Custom Modeler and Aspen Plus Evonik Industries Renmatix Dynamic simulation for safety analysis of columns Scale-up of biochemical cellulosic conversion processes See these and over 50 additional presentations and training sessions 2013 Aspen Technology, Inc. All rights reserved 40

41 What Next? Get more information now Call your AspenTech account manager or Call Aspen Telesales Direct: USA: EUROPE & MIDDLE EAST: ASIA/PACIFIC and INDIA: Or us at Presentations, videos, and getting started resources available at: Videos also available at: Contact info for today s presenter and hosts Ajay Lakshmanan ajay.lakshmanan@aspentech.com Claus Reimers claus.reimers@aspentech.com Ron Beck ron.beck@aspentech.com Julie Levine julie.levine@aspentech.com 2013 Aspen Technology, Inc. All rights reserved 41

42 Questions 2013 Aspen Technology, Inc. All rights reserved 42