Computational Fluid Dynamics (CFD) Application & Benefits for Cement Plant

Transcription

1 Computational Fluid Dynamics (CFD) Application & Benefits for Cement Plant Theme: Best Practices in Energy Efficiency in Cement Sector, A KEP initiative 7th-8th July, 2016 at My Home Industry Ltd., Mellachuruvu, Nalgonda Presented By: Akshay Shah

2 Content Introduction to Mechwell Introduction to Computation Fluid Dynamics How CFD works? CFD applications in Cement Plants Pros & Cons of CFD Benefits of CFD

3 Introduction Established in 1983, Mechwell is a multi-discipline applied R&D oriented engineering firm. Mechwell was established to provide solutions for Cement, Power & Allied industries for flow, emissions & energy consumption problems. Business: - Turnkey Solutions to Cement, Power & Allied Industries including custom engineering, specialty systems design (EFIP), manufacturing and implementation, and support to industry in emissions control to achieve SPM<30mg, heat and mass transfer, and applied energy systems. - Design, Manufacture & Supply of Expansion Joints, Dampers & Gates and EFIP s - CFD & FEA Consultancy Services. Domains : Research & Development, Testing, Manufacturing & Supply, Air Pollution Control

4 R&D CENTER FOR INNOVATION What is CFD? Fluid dynamics is the science of fluid motion. Fluid flow is commonly studied in one of three ways: Experimental fluid dynamics. Theoretical fluid dynamics. Numerically: Computational Fluid Dynamics (CFD). CFD analysis complements testing and experimentation. Reduces the total effort required in the laboratory.

5 Computational Fluid Dynamics (CFD) is the science of predicting fluid flow, heat transfer, mass transfer, chemical reactions, and related phenomena by solving the mathematical equations which govern these processes using a numerical process. The result of CFD analyses is relevant engineering data used in: Conceptual studies of new designs. Detailed product development. Troubleshooting. Redesign.

6 CFD - how it works 1. Analysis begins with a 3D model of a physical problem. 2. Fluid properties are modeled empirically. 3. Conservation of matter, momentum, and energy must be satisfied throughout the region of interest. 4. Domain is discretized into a finite set of control volumes or cells. The discretized domain is called the grid or the mesh. 5. Simplifying assumptions are made in order to make the problem tractable (e.g., steady-state, incompressible, in viscid, two-dimensional).

7 CFD - how it works 6. Provide appropriate initial and boundary conditions for the problem. 7. CFD applies numerical methods (called discretization) to develop approximations of the governing equations of fluid mechanics in the fluid region of interest. Governing differential equations: algebraic. The set of algebraic equations are solved numerically (on a computer) for the flow field variables at each node or cell. System of equations are solved simultaneously to provide solution. 8. The solution is post-processed to extract quantities of interest (e.g. lift, drag, torque, heat transfer, separation, pressure loss, etc.).

8 We use CFD analysis to carry out studies pertaining to Single Phase/Multi Phase Flow Analysis Heat transfer Combustion Analysis Material/Particle behavior As part of our FEA service, we carry out studies pertaining to Thermal studies Vibration Analysis Stress Analysis (static, dynamic, non-linear, impact) Fatigue Analysis

9 Energy Efficiency Improvement Opportunities Existing plants Use of technology for up gradation & Retrofitting of energy efficient equipment New plants Identification and selection of state-of-the-art technologies Fuel quality Blended cement Blending with imported coal for improving average quality Use of pet-coke & other combustible wastes Greater use of industrial wastes like flyash and slag for making blended cements Power supply Improving quality of power through captive generation. Performance monitoring Inter-firm comparison and benchmarking Target setting and monitoring

10 Where CFD plays major role? Cyclone Ducts Electrostatic Precipitators (ESP) Baghouse Raw Mill/ Coal Mill Kiln/ Calciner Gas Conditioning Tower

11 Thermal Efficiency Improvement in PH System Recommended Exit Temperature is 310 Deg.C Normally it is observed that PH exit Temperature is 337 Deg.C, which is on higher side, Thus Using CFD Analysis Heat transfer can be improved

12 Thermal Efficiency Improvement in PH System Reasons for High PH Exit Temperature Improper material distribution Improper flow distribution High velocity Heat Transfer Analysis in Riser Duct for Flue gas with Particles elaborates the Temperature

13 Thermal Efficiency Improvement in PH System By CFD analysis, the Exit Temperature Can Reduce & Reduction in Heat consumption about 5-20 kcal / kg clinker is possible. By means of Modification in Riser Duct Modification in Spreader Box & Feed Pipe Modification in Cyclone Modification in Riser Duct to improve Heat transfer

14 Thermal Efficiency Improvement in PH System Modification in Spreader box & Feed Pipe for Heat transfer Improvements So by CFD Modification, PH Exit Temperature can be reduced from 5 Deg C to 25 Deg C

15 Thermal Efficiency Improvement in PH System Modification in Spreader box & Feed Pipe for Heat transfer Improvements So by CFD Modification, PH Exit Temperature can be reduced from 5 Deg C to 25 Deg C

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17 Thermal Efficiency Improvement in PH System Cyclone performance analysis using CFD allows: Investigation of the flow situation Identification of the bottlenecks Optimization of the flow pattern Reduction of pressure loss Improvement of the separation efficiency Cyclone flow with high dust load: The interaction amongst particles is considered The interaction between particles and gas is considered Different sizes and particle size-distributions are considered Modification in Cyclones for efficiency Improvements

18 Thermal Efficiency Improvement in Calciner CFD analysis in the Calciner Distributions of Velocities, Temperature Concentrations of the reactant products and trajectories of coal particles Particle interaction with the gases can be predicted Particle residence time Nox,Sox & After burn fuel emission determination All the above factors are assessed for CFD analysis in a Calciner

19 Thermal Efficiency Improvement in Calciner Benefits by CFD analysis in the Calciner, Improvement in flow Distribution of Velocities which improves the combustion Improvement in coal particle distribution Reduces the high concentration of Temperature near the wall. Improvement in residual time of the Particle Overall improvement in calcinations

20 Thermal Efficiency Improvement in Kiln Hood & Kiln By CFD Analysis in the Kiln Hood & Kiln, Secondary/Tertiary air Splits Distributions of Velocities, Temperatures Flow through the Hood Size & shape of the flame in the kiln Erosion pattern in the kiln Hood Schematic of kiln with kiln Hood

21 Thermal Efficiency Improvement in Kiln Hood & Kiln Benefits by CFD analysis in the Kiln, Cold CFD Simulation: to predict the flow pattern & Improvement in flow for combustion CFD simulations in combustion: To predict the Flame length propagation Reduction in Kiln hood Erosion Temperature profile in Kiln

22 Thermal Efficiency Improvement in Waste Heat Recovery System Benefits of CFD in WHRS Improvement in Flow distribution inside the WHRS, which enhance the Thermal efficiency of the boiler Proper distribution of particles to avoid erosion of the tubes. Optimization in the pressure drop in WHRS

23 Cyclone Performance Analysis Maihar Cements Pre-modified duct

24 Cyclone Performance Analysis Maihar Cements Pre-modified Cyclone analysis with duct Modified Cyclone analysis with duct

25 Cyclone Performance Analysis Maihar Cements Reduced pressure drop by 60 mm WC(10% reduction in Fan Power). Energy savings 50 KW/h. Payback period less than 4 months.

26 CFD Model of PH System J.K. Cements OUTLET OUTLET Cyclone III Stage Riser Duct Cyclone IV Stage Elevation INLET INLET Side View

27 CFD Model of PH System J.K. Cements Project Completed and analysis report shows pressure drop up to 20mm WC Streamlines plot at the inlet duct of III stage cyclone

28 CFD Model of PH System J.K. Cements Project Completed and analysis report shows pressure drop up to 25mm WC

29 Cyclone with PH down Comer Duct Analysis Dalmia Cements Velocity profile on plane (Premodified Duct) Velocity profile on plane (Premodified Duct)

30 Cyclone & Duct Analysis Reduced pressure drop by 37mm WC. Energy savings 64 KW/h. Payback period less than 4 months.

31 Cyclone & Duct Analysis Maihar Cements Cyclone Premodified design PH Fan Inlet Modified design

32 Cyclone & Duct Analysis Maihar Cements Minimum pressure drop reduction of 12 mmwc Payback period less than 5 months

33 Cyclone & Duct Analysis India Cements Cyclone Minimum pressure drop reduction of 12 mmwc Payback period less than 5 months PH Fan inlet

34 PH system CFD results Sagar Cements Streamlines illustrate Velocity magnitude for air preheater Cyclone 6, 5, 4, 3 system

35 Raw Mill Circuit Analysis Sagar Cement To RABH Inlet PH Fan Outlet To VRM Inlet

36 Grid for Raw Mill Circuit Sagar Cements

37 CFD Results of Existing Raw Mill Circuit - Sagar Cement Stream lines and planes show the flow distribution across cyclones for pre-modified case. Power Saving by 100KW HR

38 Performance Certificate - Sagar Cements VRM CA Fan Savings-110 KW-Hr Pay Back Less than 10 months

39 Air & Flue Gas Ducts The flue gases in ducts carry coarse ash/ material particles, which under certain operating conditions hit the duct walls and other physical surfaces present within the ducts causing erosion on wall ducts. Turbulence is another problem that results in increase in pressure drop, noise, vibration etc. Flow separation occurs when a bend or expansion is too severe to allow the flow to follow the contour of the duct. This causes a wake to form, resulting in an effective reduction in the ducts cross sectional area This area reduction results in a pressure loss that can be significant.

40 Air & Flue Gas Ducts The main objective while carrying out CFD analysis of ducts is: To design turning vanes for ducts in order to reduce pressure drop, reduce turbulence and minimize erosion of duct walls, caused due to high velocity of flow. Reducing erosion of duct walls results in reduction of leakages in the ducting. Both these factors mainly, reduced turbulence and reduced erosion, result in reduction in pressure drop across the duct which in turn results in saving of power consumption.

41 Baghouse Analysis Good flow distribution inside the baghouse is very essential to increase the bag life, improved collection efficiency & minimize pressure drop. Adhering to ICAC standards & desired performace, Mechwell can improve baghouse flows by: Ensuring a uniform flow distribution of the gas to each baghouse compartment. Ensuring that flows entering each baghouse compartment are evenly distributed and that all bags are utilized within a given compartment. Preventing gas velocities that are high enough to damage a bag. Minimizing pressure losses throughout the baghouse.

42 Bag House Analysis Clair Engineers Pvt Ltd (Premodified Baghouse) (Modified Baghouse)

43 Bag House Analysis Clair Engineers Pvt Ltd (Premodified Baghouse) (Modified Baghouse)

44 Bag House Analysis ACC ltd Inlet Computational Model of Bag house Out let

45 Bag House Analysis ACC ltd Inlet 1 (GCT outlet) Inlet 2 (FLASH DRYER) Out let Fan Inlet

46 Combustion Analysis Combustion analysis using CFD allows: to improve the combustion air flow pattern to the burners in order to smooth the combustion. to compare the influence of different burner designs on flame shape. to understand the influence of several inlet parameters concerning either the fuel used, or the kiln geometrical dimensions, the position of the burner in the kiln, the various velocities.

47 Aero Acoustic Solutions Prediction & Testing of noise generated due to fan. Study of existing problem Suggestion for noise control Design, Analysis & Manufacture of Silencer.

48 Aero Acoustic Solution Jaypee Rewa, CPP

49 Conclusion Computational Fluid Dynamics (CFD) technology is very much help full for analysis for single phase & multiphase flow, combustion, heat transfer, prediction of erosion patterns. Mechwell has applied CFD technology successfully in Cement industry for process / efficiency improvement in following areas. Thermal Efficiency Improvement in Pre-Heaters Material Deposition study in PH System CFD analysis of Cyclones CFD analysis of Kiln Castables CFD analysis of Separators/ Particle Tracking CFD analysis of Raw Mills Combustion Analysis

50 Credentials Major Projects carried out by Mechwell Industries Limited Sl No. Name of the Company Projects carried out. 1 Sagar Cements Limited CFD Analysis 2 Ramco Cements Ltd CFD Analysis for Raw Mill (2) fan inlet, Cement Mill (1) fan inlet and outlet, Cement Mill (2) fan outlet 3 Dalmia Cements Ltd CFD Analysis of PH Cyclone in KHD & FLS 4 Sanghi Cements CFD Analysis of Raw Mill Cyclone with Ducting 5 J.K.Cements CFD Analysis of PH Cyclone System 6 Sanghi Cements CFD Analysis of Alkali Bypass system (As Is Condition) 7 Saurashtra Cements CFD Analysis for the Cooler ESP Inlet Duct 8 Sagar Cements Limited CFD Analysis of Calciner with Pre-heater 9 Century Cements CFD Analysis of Economiser 10 Saurashtra Cements CFD Analysis of Sepex Filter Outlet Duct to Sepex Fan Inlet Duct CFD Analysis To Resolve The Wear Out Problem in Rawmill Outlet 11 Saurashtra Cements Duct 12 Dalmia Cements Ltd CFD Analysis for Raw Mill Circuit 13 NLC Industries Limited PH Cyclone System 3D Model 14 Zuari Cements CFD For PH Cyclone 15 India Cements ltd-dalavoi CFD analysis for GCT bypass duct 16 Zuari Cements CFD Analysis of Duct of The C-line Bag House Outlet Duct 17 Shree Cements Ltd. CFD Analysis in AQC-9 and AQC-5 Boiler 18 India CementsLtd-Tirunelveli CFD Analysis of PH Cyclones 19 Orient Cements CFD Analysis of PH Down Comer Duct 20 GEA Process Engineering (India) Pvt. Ltd. CFD Analysis Service of Bag Filter forcement Mill 21 GEA Process Engineering (India) Pvt. Ltd. CFD Analysis Service of Waste Gas ESP 22 Ambuja Cement Ltd. CFD Analysis of cooler ESP Inlet Duct 23 Dalmia Cements Ltd-Ariyalur CFD Analysis of Cements mill & Raw mill ducting 24 J.K.Lakshmi Cements. CFD Analysis of Duct 25 Century Cements-Raipur CFD Analysis of Economizer Region 26 Shree Digvijay Cement Co Ltd. CFD Analysis of cooler ESP& Inlet Duct 27 Dalmia Cements Ltd-Dalmiapuram CFD Analysis in FLS PH system in Line-2 PH 28 Dalmia Bharat Enterprises Ltd-Ariyalur. CFD Analysis of Flue gas Ducting

51 These Customers Trusts US: Cement Plants Thermal Power Stations Others JAPAN MECHWELL INDUSTRIES LTD. Driven By Innovation

52 THANK YOU Contact us at: Mr. Akshay Shah Engineer Marketing , MECHWELL INDUSTRIES LTD. Driven By Innovation 14

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