Carl Vance Combustion Air Pre-heater Design Review Presentation ME 486 3/13/03

Carl Vance

Combustion Air Pre-heater Design Review Presentation

ME 486

3/13/03

Carl VanceCarl Vance

Purina Boiler Efficiency TeamPurina Boiler Efficiency Team

Members and RolesMembers and Roles Ryan CookRyan Cook

Documenter and SecretaryDocumenter and Secretary

Kofi CobbinahKofi CobbinahTeam Leader and Website Team Leader and Website ManagerManager

Carl VanceCarl VanceCommunicator and HistorianCommunicator and Historian

Matt BishopMatt BishopFinancial Officer and MediatorFinancial Officer and Mediator


SummarySummary

Client IntroductionClient Introduction

Project DescriptionProject Description

Our DesignOur Design

Mathematical ModelMathematical Model

ScheduleSchedule

BudgetBudget

ConclusionConclusion


Our Client – NestléOur Client – Nestlé Purina Purina

Client contact is John CainClient contact is John Cain

Manager of Engineering at the Flagstaff Manager of Engineering at the Flagstaff Plant.Plant.

Purina as a company:Purina as a company:Flagstaff Plant opened in 1975Flagstaff Plant opened in 1975

Employs 180 peopleEmploys 180 people

Purina is now a division of Nestlé FoodsPurina is now a division of Nestlé Foods


Purina Steam SystemPurina Steam System

The boiler produces approximately 500,000 The boiler produces approximately 500,000 lbm of steam per day. lbm of steam per day.

40%: cooking products.40%: cooking products.

50%: drying products.50%: drying products.

10%: miscellaneous areas: air and water 10%: miscellaneous areas: air and water heating systems.heating systems.

Steam production is 2/3 of the plant's total Steam production is 2/3 of the plant's total energy use.energy use.



Problem DefinitionProblem Definition NestlNestlé Purina has requested a proposal for a é Purina has requested a proposal for a

combustion air pre-heater. The goal of the combustion air pre-heater. The goal of the project is to provide savings for the plant by project is to provide savings for the plant by reducing energy costs and improving reducing energy costs and improving efficiency in the steam system.efficiency in the steam system.

Justification for the project is cost reduction Justification for the project is cost reduction and fuel conservation through higher and fuel conservation through higher efficiency.efficiency.



Client’s Needs Statement:Client’s Needs Statement:

Design of a combustion air preheater must Design of a combustion air preheater must be:be:

Efficient Efficient

Economically FeasibleEconomically Feasible

Minimize Modifications to Existing Minimize Modifications to Existing SystemsSystems


Our Design PhilosophyOur Design Philosophy

Finish Design and Construction Under Finish Design and Construction Under Budget.Budget.

Satisfy the Client’s Requirements.Satisfy the Client’s Requirements.

Design for Safety.Design for Safety.

Act with Integrity.Act with Integrity.


What is a Combustion Air What is a Combustion Air PreheaterPreheater

Device or system that heats the boiler Device or system that heats the boiler intake air.intake air.

Uses recaptured waste heat to that would Uses recaptured waste heat to that would normally leave the boiler to the normally leave the boiler to the atmosphere.atmosphere.

Ryan CookRyan Cook

Design ChoiceDesign Choice

Final Design Choice: Final Design Choice: Concentric Duct DesignConcentric Duct Design

Air enters into a duct that surrounds the Air enters into a duct that surrounds the stack.stack.

The stack transfers heat to the air by The stack transfers heat to the air by convection and radiation.convection and radiation.

The air enters into the boiler at a higher The air enters into the boiler at a higher temperature.temperature.

Ryan CookRyan Cook

Preheater Design BasicsPreheater Design Basics

Ryan CookRyan Cook

Design BenefitsDesign Benefits

Concentric Duct Design Will Provide:Concentric Duct Design Will Provide: Relatively Low Installation CostRelatively Low Installation Cost Low Material CostsLow Material Costs Low Impact on Existing SystemsLow Impact on Existing Systems High Payback on InvestmentHigh Payback on Investment Low Maintenance CostsLow Maintenance Costs

Ryan CookRyan Cook

Specifications to dateSpecifications to date

The stack height is 4.3 meters, which fixes The stack height is 4.3 meters, which fixes our duct height and will provide our our duct height and will provide our surface area for heat transfer.surface area for heat transfer.

Duct diameter will be 1.15 meters to Duct diameter will be 1.15 meters to optimize forced convection.optimize forced convection.

Ryan CookRyan Cook

Proposed DesignProposed Design

Matt BishopMatt Bishop

Forced Convection ModelForced Convection Model

Vol Flow rate (cms)2.837 k = .0263 W/(m*K) kinematic visc. = 2E-05 T(K) surface= 399.7

T(K) air = 299.7

variableO.D. (D2) I.D. (D1) hydraulic diameter X section area (m^2) airspeed (m/s) Re Pr Nu h (W/(m^2 K)) Ts - Ta (K) q" stack S.A (m^2) Energy transfer (W)

1 0.9144 0.086 0.13 22.04 59334.82 0.707 131.87 40.52 100 4051.59 12.26 49672.471.05 0.136 0.21 13.56 57824.57 129.18 25.05 2505.43 30716.521.1 0.186 0.29 9.66 56389.29 126.61 17.94 1794.03 21994.86

1.15 0.236 0.38 7.43 55023.53 124.15 13.86 1385.85 16990.471.2 0.286 0.47 5.98 53722.37 121.79 11.22 1121.55 13750.16

1.25 0.336 0.57 4.97 52481.33 119.54 9.37 936.77 11484.811.3 0.386 0.67 4.23 51296.33 117.37 8.01 800.54 9814.63

1.35 0.436 0.77 3.66 50163.66 115.29 6.96 696.11 8534.251.4 0.486 0.88 3.21 49079.93 113.30 6.14 613.61 7522.92

1.45 0.536 0.99 2.85 48042.03 111.38 5.47 546.90 6704.991.5 0.586 1.11 2.55 47047.13 109.53 4.92 491.90 6030.69

Heat Exchanger ModelHeat Exchanger Model

Cp,c (J/kg*K) Cp,h (J/kg*K)1007 1030

Hot side data

hot air density (kg/m^3) stack cross section area (m^2) vhot (m/s) Re hot Pr NuD k (W/m*K) hi (W/m^2*K) ho (W/m^2*K)

0.6964 0.6566 9.8900 233140.0000 0.6840 388.9052 0.0407 17.3102 124.1500

variable result check

Th,o (K) Th,I (K) mdot h (kg/s) mdot c (kg/s) q (Watts) Tc,I (K) Tc,o (K) Delta Tlm (K) U (W/m^2*K) Area (heat transfer)

501.20 509.10 4.52 4.52 36779.24 305.40 313.48 195.71 15.19 12.37017571501.21 36732.68 313.47 195.72 12.35387882501.22 36686.13 313.46 195.73 12.3375836501.23 36639.57 313.45 195.74 12.32129008501.24 36593.02 313.44 195.75 12.30499823501.25 36546.46 313.43 195.76 12.28870807501.26 36499.90 313.42 195.77 12.2724196501.27 36453.35 313.41 195.78 12.2561328501.28 36406.79 313.40 195.79 12.23984769

Radiation ModelRadiation Model

variableD2 D1 ε1 ε2 σ (W/(m2*K4)) stack surface area (m^2) T1 T2 q (W)1 0.9144 0.87 0.15 5.67E-08 12.26 399.7 322 1622.06

1.05 1687.841.1 1752.44

1.15 1815.911.2 1878.26

1.25 1939.541.3 1999.75

1.35 2058.941.4 2117.13

Project Monetary SavingsProject Monetary Savings

Gallons per year saved Yearly monetary savings 5- year savings

5120.473467 2355.417795 11777.088975113.991855 2352.436253 11762.181275107.510243 2349.454712 11747.273565101.028631 2346.47317 11732.365855094.547019 2343.491629 11717.458145088.065407 2340.510087 11702.550445081.583795 2337.528546 11687.642735075.102183 2334.547004 11672.735025068.620571 2331.565463 11657.82731

Gallons per year saved Yearly monetary savings 5- year savings225.83 103.88 519.40234.98 108.09 540.46243.98 112.23 561.15252.81 116.29 581.47261.50 120.29 601.44270.03 124.21 621.06278.41 128.07 640.34286.65 131.86 659.29

Convection SavingsRadiationForced Convection

Kofi CobbinahKofi Cobbinah

Accomplishments to DateAccomplishments to Date

Proposal Document has been accepted by Proposal Document has been accepted by clientclient

Mathematical Analysis of the design has been Mathematical Analysis of the design has been accepted by the client.accepted by the client.


Problems EncounteredProblems Encountered

CAD model is taking more time than CAD model is taking more time than estimated. estimated.


Future Design TasksFuture Design Tasks

Final Design will include:Final Design will include: Finalizing Mathematical ModelsFinalizing Mathematical Models Finishing CAD Models Finishing CAD Models Design ResultsDesign Results Bill of MaterialsBill of Materials Construction MethodsConstruction Methods


Project ScheduleProject Schedule

CAD Models ------------- March 24, 2003CAD Models ------------- March 24, 2003Final Design-------------- April 20, 2003Final Design-------------- April 20, 2003Capstone Presentation- April 25, 2003Capstone Presentation- April 25, 2003Final Report ------------- May 2, 2003Final Report ------------- May 2, 2003


BudgetBudget

Printing CostPrinting Cost Proposal Document ----------------- $15Proposal Document ----------------- $15 Mathematical Models Document - $15Mathematical Models Document - $15 Total--------------------------------------- $30Total--------------------------------------- $30


Team Time LogTeam Time Log

Team Time (Hours)

100

6

117.6

Team Meetings

Client Contact

Individual Work


ConclusionConclusion

We are on schedule to finish all We are on schedule to finish all deliverables and have a completed design deliverables and have a completed design as planned.as planned.

We will provide the client with a design We will provide the client with a design that is both efficient and feasible to that is both efficient and feasible to implement.implement.


Questions?Questions?

Documents

Carl Vance Combustion Air Pre-heater Design Review Presentation ME 486 3/13/03