final report on the multiport dryer - Argonne National Laboratory

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10TpSICAFMITemperaturePressureSight glassOver-temperature interlockTemperature controller (last heater element)AtomizerFlowmeterTemperature-controlled valveMultiTherm LoopFM-3T FM3Pressure reliefHeaterHeating elementT s4T minPump (P-3)Pressure reliefPressure reliefICEvaporatorSuperheaterAccumulatorPressure reliefAfter-condenser LoopFM-4After-condenserBuilding waterPump (P-4)Water outT FM4Pressure reliefT s2 T woutpRegulator AccumulatorAccumulatorHigh-pressureN 2 tankFM-1IPump (P-1)T s3Water/Steam LoopT moutTest Sectionp∆pT sinT soutCondensing channelSST FM1T winT s1Pressure reliefT coutCoolant channelT cinPressure reliefWater/Coolant LoopWater inCoolerAccumulatorpRegulatorAWater inHigh-pressureN 2 tankWater outIPump (P-2)FM-2T FM2Fig. 5. Schematic representation of multiport cylinder dryer heat transfer test apparatusMultiTherm is heated without boiling to 230°C (446°F) by an electrical resistance heater.The evaporator/superheater heat exchanger is of a shell-and-tube counter-flow design; it wasdesigned with relatively small flow passages for the MultiTherm liquid, to keep its flowturbulent. Inside the evaporator/superheater, the water exchanges heat with the MultiTherm loopfluid and changes from the liquid state into saturated or slightly superheated steam,corresponding to the system pressure. The water pressure, and thus its temperature at the testsection inlet, is controlled with the accumulator and high-pressure nitrogen tank shown in Fig. 5.
11Upon leaving the evaporator/superheater, the steam enters the 3-m-long (10-ft-long) testsection and is condensed into subcooled water (or lower-quality steam) in the condensingchannel by exchanging heat with the coolant water. The test section (shown schematically inFig. 6) consists of a rectangular condensing channel with a cross-sectional width of 18.90 mm(0.75 in.) and height of 3.14 mm (0.125 in.), and a rectangular coolant channel with the crosssectionalwidth of 18.90 mm (0.75 in.) and height of 6.13 mm (0.25 in.). The walls of both thecondensing and coolant channels are aluminum and were welded lengthwise to minimize thermalcontact resistance between the two channels. Three quartz windows were included in the testsection to observe and identify two-phase flow patterns and their transitions, including liquidhold-up and thickness of the condensate layer.The facility and test section were sized to be prototypical of a cylinder dryer with a1360 kg hr (617 lb hr ) steam flow rate. Some overcapacity was designed into it toaccommodate 130% condensing flow and to allow superheated inlet and subcooled water outletat full flow. In addition, the flow rate and test section temperatures of the water coolant weredesigned to produce the desired condensing rates as well as to maximize experimental accuracyin determining condensing heat transfer coefficients.Condensing steam flowInlet pressure/Pressure drop tapType K thermocouplesWindow (typ.)(3 x 25 mm)Pressure drop tapabcdefghiA B C D E F G H IJZType K thermocouplesSIDE VIEWWater/Coolant flowWater outWater inABCDEFGHIJTOP VIEWFig. 6. Detailed schematic representation of test section
Page 1: ARGONNE NATIONAL LABORATORY9700 Sou
Page 4 and 5: Figures1 Resistances to heat transf
Page 6 and 7: 21 INTRODUCTIONThe pulp and paper i
Page 8 and 9: 4A B C D EF G HA - Steam convection
Page 10 and 11: 6In some cases, spoiler bars have b
Page 12 and 13: 8The structure of the multiport cyl
Page 16 and 17: 12Nine Type-K thermocouples (T a,T
Page 18 and 19: 14D. After-condenser heat dump.The
Page 20 and 21: 165.2 ShutdownA. Turn off all Multi
Page 22 and 23: 18∆qh(z) =s(z)∆A s [ T s(z) −
Page 24 and 25: 2010080Heat Loss (W)60402000 20 40
Page 26 and 27: 22Average Condensing Heat Transfer
Page 28 and 29: 24x = 0.77160140∆ T = 5.6o Cx = 0
Page 30 and 31: 26to produce paper at a higher rate
Page 32 and 33: 28a steady-state market penetration
Page 34 and 35: 30• The condensing heat transfer
Page 36 and 37: 32[9] J. C. Y. Wang, L. J. Qiu, and
Page 38 and 39: 34more of the available energy from
Page 40 and 41: 36Market Penetration, Energy Saving
Page 42 and 43: 38Market Penetration, Energy Saving

final report on the multiport dryer - Argonne National Laboratory

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