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Steam System Designand Best PracticesRelated to Kiln DryingNew England Kiln Drying Association – Steam Design and Best Practices – HerLine Technologies

What is Steam? Like other substances water can exist in the formof a solid, a liquid or a gas. Gaseous form of water is called STEAMHOTIt’s PowerfulIt’s Easy It’s New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Why use Steam ? Made from water, which is relatively inexpensive andplentiful commodity available through out the world Carries relatively large amounts of energy in a small mass Temperature can be adjusted accurately by controlling itspressure using control valves Environmental friendly Relatively inexpensive to generate when firing with woodchipsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam - the best choiceWhy other systems fail to measure up to steam ?1. Gas fired direct heating Higher operating cost than wood fired boilerMore difficult to controlHigher MaintenanceRequires separate humidification systems2. Electric heating Very high cost to operateRequires separate humidification systems3. Hot water systems Carries less than 1/5th (20%) the heat (Btu’s) of SteamHigher system installation costHigher operating costsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Requirements for an Effective,Efficient and Safe Steam System Good initial system designHigh quality system equipment and componentsGood knowledge of system operational safetiesand periodic testing of safety devicesGood system operational knowledge and practicesRegular tuning and maintenanceReplacement of old or worn componentsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam System Sub-Systems Steam Generation Steam Distribution Steam Utilization Condensate RecoveryNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam GenerationNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam Generation – the Boiler House Steam Boiler – high or low pressureBoiler Feed Water Tank – minimumCondensate Surge Tank & DA Tank – idealWater Softeners for make-up waterChemical Treatment System for boiler waterSurface blow down (TDS) control system for boiler –recommendedFlash steam and blow down heat recovery systems optionalNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

STEAM GENERATIONNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Generating Quality SteamGood qualitysteam to plantFeed waterwithimpuritiesBuild up ofimpurities in theboiler – surfaceblow down todrain or heatrecoveryImpurities - bottom‘blow down’ to wasteNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Typical Simple Boiler Feed WaterTanksVent toAtmosphereCondensateReturnsVent toAtmosphereCondensateReturnORTo BoilerTo BoilerSURGE-1BF-1BF-1BF-2New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Typical Deareator TankDirect condensate returns,pumped returns & make-up waterLow pressure steamsupply to deareator0 LB/HTo BoilerDEA-1New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Surge and DA Tank CombinationSurge tank isvented to theatmosphereMake-up water isusually added hereand pre-heatedTypicalCondensatepumpCR-1DA tank ispressurizedwith steam0 LB/H5 PSIG? PSIGPRV-10 LB/HSURGE-1DEA-1New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Optional Heat Recovery SystemsTypical Blowdown HeatRecoverySystemNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Complex Flash Recovery SystemNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

The Steam DistributionSystemNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam Distribution System Proper layout design & pipe sizing of mainsPiping always pitched in the direction of flowUse of eccentric reducers to eliminate creation ofcondensate collection points (low spots) in pipingUse of separators to eliminate wet steamProper drip trap stations in all required locationsUse of air vents at all end-of-main locationsMake steam main branch take-offs from top of pipeUse of pressure reducing valves as needed or desiredPut strainers before control valves, traps and pumpsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam DistributionTypical Steam CircuitNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Typical Steam Distribution HeaderNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Pipe Sizing Greater Heat Loss Greater Cost Greater Volume of CondensateFormed Greater System Pressure Drops Not Enough Volume of Steam Water Hammer and ErosionNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam Volume1 - 12 oz Can of Soda2 - 4 Drawer Filing Cabinets 1 - 4 Drawer Filing Cabinets 1-Drawer of Filing Cabinet0.012 cu ft.20.10 cu ft @ 0 psig [1675:1]11.18 cu ft @ 15 psig [867:1]2.97 cu ft @ 100 psig [243:1]New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

SizingSteamLinesNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam MainRelaying to Higher LevelFall 1/250SteamRelayto highlevel150 - 300 ftDrain PointsSteam FlowNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam Line sateNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam SeparatorsHow Separators WorkWetSteamDry SteamS3 SeparatorNew England Kiln Drying Association – Steam CondensateDesign & Best Practices– HerLine TechnologiesOutlet

Proper Drip Trap StationSteam FlowCondensateCrossSectionCorrect9PocketSteam Trap SetSteam FlowCross SectionIncorrectSteam Trap Set8New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Typical Steam Main Drip StationDHSize of Main ‘D’Collection Leg Diameter1/2” to 6”Same dia. as main ‘D’6” & larger2 to 3 Pipe Sizes Smallerthan Main, But NeverSmaller than 6”Length of Collection Leg ‘H’Automatic Start up: ‘H’ to be 28” orMoreSupervised Start up: Length tobe1-1/2 times steam MainDiameter, but never shorter than18”New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam Traps ina Typical Steam CircuitNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Air VentingBalanced PressureAir VentSteam MainAirThermodynamicSteam Trap SetNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Branch ew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Supply LegMainShut OffValveTrap SetNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

StrainersStrainers should be installed ahead of pressure reducing valves,control valves, flow meters and steam traps. All these components aresusceptible to scale, dirt and debris. Screens of 60/100 mesh for valvesand flow meters, 20 mesh for traps.Control ValveStrainerNote:Turnsteam pipe line strainers 90 so the “Y”is parallel with the floor, not pointingdown at it. This will eliminate thecondensate pocket shown here.New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Pressure ReductionNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Why Reduce Pressure?PRO It’s better to run boilers at higher pressure for effective systemoperation and best system responseSteam should be used at lowest pressure to meet process systemtemperature requirements for highest efficiency and ease ofcontrolCON Adds additional system devices such as pressure reducing valvesand safety valves to be concerned withLower pressures increase the size of piping and systemcomponents which add costNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Pilot Operated PRV CutawayNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Pressure Reducing StationNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Typical Pressure Reducing StationsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Typical Pressure Reducing StationsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam Main Piping Use schedule 40 carbon steel pipeSize for proper velocity at operating pressureSize for current and future needsPitch in the direction of flowUse eccentric reducers to prevent condensate collection poolsInstall proper drainable drip legs with allowance for dirt legs andtrap stationsLocate trap stations at 150’ min and 300’ max on long linear runsLocate trap stations at all changes in elevation, at the bottom ofdrop lines and at the end of mainsAll branch take offs should be from the top of the main wheredry steam is availableAir vents are also recommended at the ends of the mainInsulate all steam pipingNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam UtilizationNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Steam Utilization Is the ultimate goal of any steam system and itincludes all the heat transfer systems andfunctions In the case of Kiln Drying, it would provide theheat for drying and the steam for humidificationNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Selection from Steam TablesGAUGE ABSOLUTE TEMP SENSIBLE LATENT TOTAL VOLUME LATENToPRESSURE PressureFHeatHeatHeatSteam 970946912881115011641180119026.813.96.683.95.4 : 14.4 : 13.4 : 12.9 : 1GAUGEPRESSUREVacuumins 0331000982972110311301143115033373382814.7 : 177 : 16.1 : 15.5 : 1New England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

PRESSURE & FLOWDifferential Pressure: Is the difference between the inlet pressure and the outlet pressureacting upon any steam component such as a trap, valve, etc.Elevation ChangesFlowNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

ControlValvesVacuumBreakersKiln TypicalSteam &Condensate SystemAir VentsDrip TrapsCoil TrapsCondensatePumpNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

MODULATING STEAM TEMPERATURE CONTROLTypical Kiln Air CoilSteam Control LayoutCONTROLVALVEVACUUMBREAKERAIR FLOWVACUUMBREAKERAIR VENTAIR VENTTRAPAIR FLOWGRAVITY DRAIN DOWN-NO LIFT-NO CHECK VALVESTRAPGRAVITY DRAIN DOWN-NO LIFT-NO CHECK VALVESNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Pre-Dryer Control Layout at AMF Bowling ProductsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Barriers to Heat TransferWhen steam comes into contact with a cooler surface, it gives up itslatent heat and condenses.DirtFilmWaterCondensate FilmAir FilmMetal Heating atureNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Effective Efficient Heat Transfer Good quality dry steam Remove air from steam and coils Use properly sized F&T traps on coils – not too small & don’t go too largeProvide for 12” minimum drop to trapMake sure traps are gravity draining without any lift in pipingInstall vacuum breakers on the inlet of each coil to break vacuum lock which impedesdrainageTrap each coil section independently, don’t group coils on a single trapKeep coil fin and tube area as clean as possible Use air vents on mains and particularly on coils before trapsRemove condensate completely Use separators if necessaryPower wash occasionally as necessaryUse only the highest quality control componentsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Use High Quality Industrial GradeValves Pneumatic Actuated–least expensiveand most reliable Use Positioners when possible–betteraccuracy and control Use high pressure air when possible–keeps cost of actuators down Hardened stainless steel trim-plug &seat Good live loaded packing stem sealsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Vacuum BreakersSimple ball check types are the best and most reliable typeNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Air VentsThermostatic Air VentsforSteam SystemsNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Float Trap with Thermostatic Air VentInWater Level Increases,the Float Rises andthe Valve OpensOutNew England Kiln Drying Association – Steam Design & Best Practices – HerLine Technologies

Proper System Design Makes aDifference.Accurate reliable control Air Venting Condensate Removal equ