ML16120A326
| ML16120A326 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 04/18/2016 |
| From: | Entergy Nuclear Operations |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML16120A302 | List:
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| References | |
| PNP 2016-015 | |
| Download: ML16120A326 (89) | |
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FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-1 of 1.2-11 1.2GENERAL PLANT DESCRIPTION 1.2.1PLANT SITEThe site for the Palisades Plant consists of approximately 432 acres on theeastern shore of Lake Michigan, in Covert Township, approximately four andone-half miles south of South Haven, Michigan. The area adjacent to the siteis sparsely populated and is primarily farmland. The population along thelake increases during the summer months. See Subsection 2.1.2 for detailson demography and Figure 2-2 for site layouts.The exclusion area for Palisades is defined as the property boundary shownon Figure 2-2. The minimum exclusion distance for the site is approximately2,300 feet (667 meters) and the nearest population center area of more than24,000 residents is constituted by the cities of Benton Harbor and St Josephwhich are approximately 16 miles south of the site.
1.2.2PLANT ARRANGEMENTFigure 1-1, Plant Site Plan and Plant Area Plan, displays the primary powerblock structures arrangement. The turbine building for the Palisades Plant isoriented parallel and adjacent to the shoreline of Lake Michigan, with thereactor containment building located on the east, or landward, side of theturbine building. The office and auxiliary facilities are situated east of thenorth end of the turbine building so that the entire complex is L-shaped. Thereactor containment structure is located inside the corner of this "L."Equipment layouts are shown in Figures 1-2 through 1-18.The containment building houses the NSSS, consisting of the reactor, steamgenerators, primary coolant pumps, pressurizer and some of the reactorauxiliaries which do not require access during power operation. Thecontainment building is served by a circular bridge crane.The turbine building houses the turbine generator, condenser, feedwaterheaters, condensate and feed pumps, turbine auxiliaries and certain of theswitchgear assemblies. The north end of the turbine building providesadditional shop, laboratory and office space.The auxiliary building and auxiliary building addition (radioactive wastebuilding) houses the waste treatment facilities, engineered safeguardscomponents, heating and ventilating system components, the emergencydiesel generators, switchgear, laboratories, offices and the control room. Thespent fuel pool and the new fuel storage facilities are located in a separatesection of the auxiliary building (Chapter 9) which is under controlledventilation whenever spent fuel is being moved or stored in that section. Fueltransfer to and from containment is through a fuel transfer tube.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-2 of 1.2-11The condensate and makeup demineralizer building (feedwater puritybuilding) was constructed during the feedwater purity modification. It housesthe raw water filtration system, the reverse osmosis pretreatment system, themakeup demineralizer system, various components of the condensatedemineralizer system, regeneration chemicals handling system, feedwaterpurity service and instrument air, chemical storage and a boiler room.Because of continuing concern with resin leakage and sodium release, thecondensate demineralizer system has been rendered inoperable and retiredin place.The intake structure houses the service water and fire protection pumps.Prior to converting the Plant from once-through cooling to closed-cyclecooling, this building contained the circulating water pumps.The cooling tower pump house contains two vertical pumps with sufficienthead capacity to circulate the tube side condenser cooling water up to thecooling tower inlet near the tower top. The cooling tower basins are elevatedsome 20 feet above the Plant.The circulating water cooling towers are cross-flow mechanical draft, locatedapproximately 500 and 1,000 feet from the Plant.
Onetower contains 18 cellsand is designed for a 30
°F range and the other tower contains 16 cells and isdesigned for a 32
°F range.1.2.3CONTAINMENTThe containment building uses a prestressed concrete design. The buildingis a vertical right cylindrical structure with a dome and a flat base. Thebuilding interior is lined with carbon steel plate for leak tightness. Inside thestructure, the reactor and other NSSS components are shielded withconcrete. An unlined steel ventilation stack is attached to the outside of thecontainment building and extends to an elevation equal to the top of thecontainment dome. Access to portions of the containment building duringpower operation is permissible.The containment building, in conjunction with engineered safeguards, isdesigned to withstand the internal pressure and coincident temperatureresulting from the energy released in the event of a DBA. The originalstructure design conditions are an internal pressure of 55 psig, a coincidenttemperature of 283
°F and a leak rate of 0.1% per day by weight at designtemperature and pressure. Actual containment conditions calculated to occurfollowing accidents are discussed in Chapter 14.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-3 of 1.2-11The containment is equipped with two independent, full-capacity systems forcooling by air recirculation or building sprays after the postulated DBA. Therecirculation system is designed to provide maximum containmentatmosphere mixing, however, fan operation is not credited in the analysis formixing. The cooling coils and fans are sized to provide adequate containmentcooling following a DBA with three of the four units in service on emergencypower. The building sprays supply borated water to cool and simultaneouslyremove some of the released fission products from the containmentatmosphere. The spray system is sized to provide adequate cooling with twoof the three containment spray pumps in service and the two shutdown heatexchangers in operation. Actual system capabilities and operatingrequirements for fans, coolers and sprays are discussed in Chapters 6 and 14.The pumps initially take suction from the safety injection and refueling waterstorage tank. When this supply is depleted, the suction is transferredautomatically to the containment sump. By the onset of this recirculationphase, sodium tetraborate is dissolved in the sump solution to neutralize theboric acid.
1.2.4NUCLEAR STEAM SUPPLY SYSTEM (NSSS)The NSSS consists of a pressurized water reactor with two closed loops. Theprincipal components and supporting systems of the NSSS are the reactorvessel, internals, control rods, control rod drives, slightly enriched fuel, two"U" tube steam generators, four primary coolant pumps, primary systempiping, pressurizer, quench tank, Chemical and Volume Control System,Safety Injection System, nuclear and process instrumentation, and theReactor Protective System.The NSSS uses chemical shim and control rods for reactivity control andsupplies steam to a four-flow, tandem-compound, hydrogen-cooled turbinegenerator.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-4 of 1.2-11The NSSS is expected to have adequate margin to obtain an ultimate outputof 2,650 MWt. The steam and power conversion equipment is designed for amaximum expected gross capability of 865 MWe. See Table 1-2 forequipment design. The Primary Coolant System operates at a nominalpressure of 2,060 psia. The primary coolant enters the upper section of thereactor vessel, flows downward between the reactor vessel shell and the corebarrel, and passes through the flow skirt and into the lower plenum where theflow distribution is equalized. The coolant then flows upward through the coreremoving heat from the fuel rods, exits from the reactor vessel, and passesthrough the tube side of the two vertical "U" tube steam generators whereheat is transferred to the secondary system. Two primary coolant pumps persteam generator return the primary coolant to the reactor vessel.
1.Reactor Vessel and InternalsThe reactor vessel and its removable hemispherical closure head arefabricated from carbon steel and are lined with 308/309 stainless steel.In the areas of internal attachments, the interior is clad with Ni-Cr-Fealloy. A fixed hemispherical head is attached to the lower end of theshell. The reactor vessel is supported on three pads welded to theunderside of the coolant nozzles.The reactor core is supported from the reactor vessel flange and isfueled with uranium in the form of slightly enriched UO 2 pellets.Zircaloy-4or M-5 tubing is used for the fuel cladding. The corecontains 204 fuel bundles and 45 control rods.A three-to-four batch, mixed central zone fuel management plan isemployed and a further reduction in nuclear peaking is obtained bylocal enrichment zoning within the bundles. Boric acid dissolved in thecoolant is used as the neutron absorber to provide long-term reactivitycontrol. In order to reduce the boric acid concentration required at thebeginning of the fuel cycle, and thus to make the moderator coefficientof reactivity more negative, mechanically fixed, burnable poison rodsare utilized.
2.Steam GeneratorsThe two steam generators are vertical shell and "U" tube units (seeTable 4-4).The steam generated in the shell side of the steam generator flowsupward through moisture separators which reduce its moisture content.All surfaces in contact with the primary coolant are either stainlesssteel or Inconel in order to maintain primary coolant purity.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-5 of 1.2-11 3.Primary Coolant PumpsThe coolant in the primary loop is circulated by four primary coolantpumps of the single suction centrifugal type. The pump shafts aresealed by mechanical seals. The seal performance is monitored bypressure and temperature sensing devices in the seal water circulationsystem.4.Primary System PipingEach of the two loops which make up the Primary Coolant Systemconsists of one 42-inch ID pipe and two 30-inch ID pipes. The largerpipe carries the water from the reactor to the steam generator. Theflow from the steam generators is pumped to the reactor through the30-inch ID pipes.
5.Pressure Control SystemThe pressure in the Primary Coolant System is controlled by regulatingthe temperature of the coolant in the pressurizer, where steam andwater are held in thermal equilibrium. Steam is formed by thepressurizer heaters or condensed by the pressurizer spray to reducepressure variations caused by expansion and contraction of theprimary coolant due to primary system temperature changes.Overpressure protection is provided by spring-loaded safety valvesconnected to the pressurizer. The discharge from the pressurizersafety valves is released under water in the pressurizer quench tank,where it is condensed and cooled. In the event that the dischargedvolume of steam exceeds the capacity of the quench tank, the tankrelieves via a rupture disc to containment.
6.Reactor ControlThe reactor is controlled by a combination of 45 control rods anddissolved boric acid in the primary coolant. Forty-one of the controlrods are full length, and four partial-length rods are also provided. Thepart-length rods are maintained in the fully withdrawn position duringreactor operation and do not insert following a reactor trip.Boric acid addition or removal is used for reactivity changes associatedwith major changes in water temperature during start-up andshutdown, fuel burnup and xenon variations. Additions of boric acidalso provide an increased shutdown margin during initial fuel loading,refuelings and approaches to cold shutdown condition. The boric acidsolution is prepared in a boric acid batching tank, stored in two storagetanks, and maintained at a temperature sufficient to preventprecipitation. The tanks are connected to the charging pumps throughlocked open manual and automatic valving.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-6 of 1.2-11Control rod movement provides changes in reactivity required forpower changes or for shutdown to a hot condition. The control rodsare made of a silver-indium-cadmium alloy clad with stainless steelwelded into a cruciform configuration. They are actuated by controlrod drive mechanisms mounted on the head of the reactor vessel. Thecontrol rod drive mechanisms, which are rack-and-pinion units, aredesigned to permit rapid insertion of the control rods into the reactorcore by gravity.
7.Chemical and Volume Control SystemThe purity of primary coolant is controlled by continuous purification ofa portion, "letdown," of the total primary coolant volume. Coolant isremoved from the primary system and is initially cooled in theregenerative heat exchanger. The coolant letdown is then reduced inpressure by orifices and letdown back pressure valves and again intemperature as it passes through the letdown heat exchanger. Theletdown then flows through one of three demineralizers wherecorrosion and fission products are removed through a filter which trapsparticulate matter in the effluent from the demineralizer. It is thensprayed into the volume control tank.The volume control system automatically controls the rate and amountof coolant returned to the Primary Coolant System to maintain thepressurizer level within a control band and thereby compensates forchanges in volume due to primary coolant temperature changes. Thevolume control tank is sized to accommodate primary coolant inventorychanges resulting from load changes from hot standby to full power.This mode of operation, using the volume control tank as a surge tank,decreases the quantity of liquid and gaseous waste which otherwisewould be generated.8.Chemical TreatmentPrimary system makeup water is taken from the demineralized waterstorage system and from the concentrated boric acid tanks. Themakeup water is pumped through the regenerative heat exchanger intothe primary loop by the charging pumps.Bleed from the primary system during a boron concentration reductionis routed to the radwaste liquid receiver tanks for processing throughthe Radwaste System before reuse in the Plant or disposal to the lake.Chemical injection equipment is provided for the addition of corrosioncontrol chemicals to the primary loop water. Hydrogen is added toprimary coolant for oxygen scavenging through the volume control tank.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-7 of 1.2-11Depleted zinc ions are added to primary coolant through the ZincAddition System for the removal of radioactive cobalt ions from PCSpiping (inner walls). Removal of the radioactive cobalt ions reducesdose to personnel from PCS piping.
9.Nuclear Control and Instrumentation a.Nuclear Plant ControlThe reactor control system provides for start-up and shutdownof the reactor and for adjustment of the reactor power inresponse to turbine load demand. The NSSS is capable offollowing a ramp change from 15% to 100% power at a rate of5% per minute and at greater rates over smaller load changeincrements up to a step change of 10%. This control isaccomplished by manual rod motion. A temperature computingstation calculates the reactor average temperature and areference temperature value corresponding to turbine power.The reactor average coolant temperature and the referencetemperature values are displayed to operators who manuallyadjust coolant temperature by moving control rods. Regulationof the primary temperature in accordance with this programmaintains the secondary steam pressure and matches reactorpower to load demand.b.Reactor Neutron MonitoringThe nuclear instrumentation consists of excore and incore fluxmonitoring chambers. Eight channels of excore instrumentationmonitor the neutron flux and six of the eight channels providereactor protection signals during start-up and power operation.Two of the channels follow the neutron flux through the start-up range.The incore monitors consist of rhodium neutron detectors and athermocouple. This system provides information on neutron fluxand temperatures in the core.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-8 of 1.2-11 c.Reactor Protective SystemThe reactor parameters are maintained within acceptable limitsby the inherent characteristics of the reactor, by the control rodsystem, by boron control and by the operating procedures.Departures from these limits are indicated audibly and visuallyin the control room. A Reactor Protective System initiatesreactor shutdown if selected values of parameters areexceeded. The protective system is divided into four channels.Each channel receives trip signals from sensors when therelevant parameter values are exceeded and a two-of-fourcoincident logic system sends a "deenergize" signal to thecontrol rod drive mechanism clutch power supplies.The control rods are released and the reactor is shut downwhen the clutch power supplies are deenergized. Redundantsensors are provided for the reactor shutdown functions so thatfailure of any one sensor does not prevent a reactor trip.
d.Other Safety-Related Protection and Control SystemsWhile the Reactor Protective System protects the reactor coreand the engineered safeguards controls protect against a Lossof Coolant Accident (LOCA), other safety-related Class 1Econtrol and instrumentation systems are provided to allow asafe shutdown of the Plant, assure decay heat removal andprotection of fluid systems boundaries. Such systems arereactor shutdown controls, primary coolant and other liquidboundaries overpressure protection, automatic auxiliaryfeedwater initiation and containment hydrogen control.
e.Process InstrumentsCritical primary system parameters are monitored by redundantchannels. Additional temperature, pressure, flow and liquidlevel monitoring is provided as required to keep the operatingpersonnel informed of Plant conditions and to provideinformation from which Plant processes can be evaluated orregulated. The plant gaseous and liquid effluents are monitoredfor radioactivity. The levels are displayed and recorded andhigh values are annunciated.Area monitoring stations are provided to monitor radioactivity atselected locations around the Plant. High-pressure or high-radiation conditions within the containment building initiatecontrol action to isolate the containment.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-9 of 1.2-1110. Safety Injection SystemFour safety injection tanks are provided, each connected to one of thefour reactor inlet lines. Each tank has a volume of approximately2,000 cubic feet containing approximately 1,000 cubic feet of boratedwater at a concentration of 1,720-2,500 ppm and pressurized byapproximately 1,000 cubic feet of nitrogen at approximately 200 psia.In the event of a large Loss of Coolant Accident, the borated water isforced into the Primary Coolant System by the expansion of thenitrogen. The water in three tanks will adequately refill and reflood theentire core. In addition, borated water will be injected into the reactorvessel to cool the core via the same nozzles used by the SI tanks bytwo low-pressure and two high-pressure injection pumps taking suctionfrom the 285,000-gallon safety injection and refueling water storagetank (SIRW). For maximum reliability, the designed capacity from thecombined operation of one high-pressure and one low-pressure pumpprovides adequate injection flow for any Loss of Coolant Accident.Upon depletion of the storage tank supply, the high-pressure pumpsuction automatically transfers to the containment sump and thelow-pressure pumps are shut down. One high-pressure pump hassufficient capacity to maintain the core water level at the start ofrecirculation. In the event of a DBA, at least one high-pressure andone low-pressure pump would receive power from the emergencypower sources. Both high- and low-pressure injection pumps arelocated outside the containment building to permit access for periodictesting during normal operation. The pumps discharge into separateheaders which lead to the containment. Test lines are provided topermit running the pumps for test purposes during Plant operation.11. Shutdown Cooling SystemThe Shutdown Cooling System consists of a forced circulation heatremoval loop which includes the low-pressure safety injection pumpsand the shutdown heat exchangers. The system is designed totransfer heat from the Primary Coolant System to a closed loop coolingsystem during normal shutdown, refueling and maintenanceoperations.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-10 of 1.2-11Emergency shutdown cooling during a loss of normal and standbyelectrical power is accomplished by allowing natural circulation of theprimary coolant to transfer heat from the core to the steam generators.The steam that is generated is released to the atmosphere as required.One of two auxiliary electric-driven feedwater pumps operating fromeither emergency diesel generator, or an auxiliary turbine-drivenfeedwater pump, supplies feedwater to the steam generators duringthis period. A 100,000-gallon supply of demineralized water availableto these pumps is sufficient for eight hours of decay heat removal. Inaddition, the Plant has the capacity for long-term cooling incorporatingthe ability to flush the reactor core and prevent post-LOCA boric acidprecipitation.12. ShieldingShielding is provided so that radiation exposure of personnel will notexceed the recommended limits of 10 CFR, Part 20. The design ofradiation shielding is dependent both on the extent of access requiredto a particular location and on the sources of radiation adjacent to thatlocation.The control room is shielded to permit continuous occupancy followingany accidental release of radioactivity in the containment.
1.2.5TURBINE GENERATORThe turbine is an 1,800 r/min tandem-compound unit with external moistureseparation and live steam reheating. The double-flow high-pressure elementexhausts to two double-flow low-pressure elements through moistureseparators and reheaters. The low-pressure elements discharge to the maincondenser and the condensate is returned to the steam generators throughsix stages of feedwater heating. Steam is extracted for feedwater heatingand for two auxiliary turbines which drive the two half-sized steam generatorfeed pumps.The feedwater cycle is of the closed type with deaeration effected in thecondenser. Feedwater heaters are arranged in two parallel trains, each withone high-pressure and five low-pressure heaters. Separate feedwaterregulating valves control the flow to each of the two steam generators.The 1,800 r/min, hydrogen inner-cooled generator is rated at 955,000 kVA at75 psig hydrogen pressure, 0.85 power factor and 0.
62 short circuit ratio.Field excitation is provided by a brushless exciter directly coupled to the generator shaft.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-11 of 1.2-11The turbine generator has a guaranteed capability of 811,776 kWe gross at1.8 inches Hg absolute back pressure and 0.25% makeup with inlet steamconditions of 735 psia and 509°F. The maximum calculated capacity of theturbine generator is 865 MWe gross.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 21SECTION 1.7Page 1.7-1 of 1.7-2 1.7RESEARCH AND DEVELOPMENT REQUIREMENTSThe design of the Palisades Plant is based upon concepts which have beensuccessfully incorporated in pressurized water reactor systems. However,certain Palisades specific Combustion Engineering development tests havebeen performed and are listed below. These tests were completed prior toinitial Plant start-up.
1.7.1FLOW MIXING AND FLOW DISTRIBUTIONTests have been run to measure the flow mixing factor. Dye dispersion ratewas measured in a series of full-scale and larger than full-scale mock-ups ofvarious fuel bundle flow channel configurations. These tests were run in acold-water test loop.A larger than full-scale model of the Palisades bundle inlet region has beentested in a cold-water flow loop to determine the effect of minor flowmaldistributions due to inlet structure nonuniformities, and to verify theeffectiveness of certain steps taken to improve inlet flow.
1.7.2CONTROL ROD TESTSA series of tests were run to demonstrate the adequacy of the control rod andits guidance system. Cold-water flow testing of a slightly underscale model offour bundles and a cruciform control rod was performed. These tests wereconducted with mechanical misalignments exceeding design values.In addition to the cold-water tests, a test program has been performed using afull-scale model, including a prototype mechanism under reactor conditions offlow, temperature and pressure in the CE Utility Reactor Components TestFacility at Windsor. The purpose of this program was to assess the effects ofmechanical misalignments, of thermal distortions which have been measuredon model fuel bundles and on a prototype control rod, of cross flow and ofupper limit conditions of axial flow and system pressure.A series of mechanical tests have been run on structural components of theAg-In-Cd control rod blade.
1.7.3CONTROL ROD DRIVE MECHANISMSAn extensive development program has been completed on the control roddrive mechanisms. This program has included up to 130,000 feet of travel onvarious components and 350 full-height drops. The production mechanismdesign incorporates improvements derived from experience gained on thisprogram.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 21SECTION 1.7Page 1.7-2 of 1.7-2 1.7.4FUEL BUNDLE DESIGNCombustion DesignCold-water flow-induced vibration tests on fuel rods and subassemblies andmechanically induced vibration tests in air on model bundles have beencompleted. An extensive hot flow test program, including the effects of forcedcross flow, has been completed using essentially full-length, though not fullcross-section, bundles. Total time at reactor conditions (or conditionsbelieved to be more severe) exceeded 13,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />. These tests have beensupplemented by a basic program on the mechanism of grid to fuel rod wearconducted in a static autoclave with mechanically induced relative motion.These tests substantiate the adequacy of the fuel bundle design for itsexpected service.In addition to this program, four full-scale model fuel bundles were tested byCombustion Engineering at reactor conditions (or more severe conditions) inthe Utility Reactor Components Test Facility. Beginning with the second fuelcycle, Combustion Engineering fuel has not been used.Current Fuel DesignComparable developmental testings, as described previously, have also beenperformed by the current fuel vendor. Refer to Subsection 3.3.4.3 for details.
1.7.5REACTOR VESSEL FLOW TESTSA one-fifth scale model of the reactor vessel and its internals has beenconstructed and subjected to airflow testing at the Battelle Memorial InstituteLaboratories at Columbus, Ohio. These tests have investigated flowdistribution, pressure drop and the tracing of flow paths within the vessel forall four pumps running and various part-loop configurations.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-1 of 1.2-11 1.2GENERAL PLANT DESCRIPTION 1.2.1PLANT SITEThe site for the Palisades Plant consists of approximately 432 acres on theeastern shore of Lake Michigan, in Covert Township, approximately four andone-half miles south of South Haven, Michigan. The area adjacent to the siteis sparsely populated and is primarily farmland. The population along thelake increases during the summer months. See Subsection 2.1.2 for detailson demography and Figure 2-2 for site layouts.The exclusion area for Palisades is defined as the property boundary shownon Figure 2-2. The minimum exclusion distance for the site is approximately2,300 feet (667 meters) and the nearest population center area of more than24,000 residents is constituted by the cities of Benton Harbor and St Josephwhich are approximately 16 miles south of the site.
1.2.2PLANT ARRANGEMENTFigure 1-1, Plant Site Plan and Plant Area Plan, displays the primary powerblock structures arrangement. The turbine building for the Palisades Plant isoriented parallel and adjacent to the shoreline of Lake Michigan, with thereactor containment building located on the east, or landward, side of theturbine building. The office and auxiliary facilities are situated east of thenorth end of the turbine building so that the entire complex is L-shaped. Thereactor containment structure is located inside the corner of this "L."Equipment layouts are shown in Figures 1-2 through 1-18.The containment building houses the NSSS, consisting of the reactor, steamgenerators, primary coolant pumps, pressurizer and some of the reactorauxiliaries which do not require access during power operation. Thecontainment building is served by a circular bridge crane.The turbine building houses the turbine generator, condenser, feedwaterheaters, condensate and feed pumps, turbine auxiliaries and certain of theswitchgear assemblies. The north end of the turbine building providesadditional shop, laboratory and office space.The auxiliary building and auxiliary building addition (radioactive wastebuilding) houses the waste treatment facilities, engineered safeguardscomponents, heating and ventilating system components, the emergencydiesel generators, switchgear, laboratories, offices and the control room. Thespent fuel pool and the new fuel storage facilities are located in a separatesection of the auxiliary building (Chapter 9) which is under controlledventilation whenever spent fuel is being moved or stored in that section. Fueltransfer to and from containment is through a fuel transfer tube.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-2 of 1.2-11The condensate and makeup demineralizer building (feedwater puritybuilding) was constructed during the feedwater purity modification. It housesthe raw water filtration system, the reverse osmosis pretreatment system, themakeup demineralizer system, various components of the condensatedemineralizer system, regeneration chemicals handling system, feedwaterpurity service and instrument air, chemical storage and a boiler room.Because of continuing concern with resin leakage and sodium release, thecondensate demineralizer system has been rendered inoperable and retiredin place.The intake structure houses the service water and fire protection pumps.Prior to converting the Plant from once-through cooling to closed-cyclecooling, this building contained the circulating water pumps.The cooling tower pump house contains two vertical pumps with sufficienthead capacity to circulate the tube side condenser cooling water up to thecooling tower inlet near the tower top. The cooling tower basins are elevatedsome 20 feet above the Plant.The circulating water cooling towers are cross-flow mechanical draft, locatedapproximately 500 and 1,000 feet from the Plant.
Onetower contains 18 cellsand is designed for a 30
°F range and the other tower contains 16 cells and isdesigned for a 32
°F range.1.2.3CONTAINMENTThe containment building uses a prestressed concrete design. The buildingis a vertical right cylindrical structure with a dome and a flat base. Thebuilding interior is lined with carbon steel plate for leak tightness. Inside thestructure, the reactor and other NSSS components are shielded withconcrete. An unlined steel ventilation stack is attached to the outside of thecontainment building and extends to an elevation equal to the top of thecontainment dome. Access to portions of the containment building duringpower operation is permissible.The containment building, in conjunction with engineered safeguards, isdesigned to withstand the internal pressure and coincident temperatureresulting from the energy released in the event of a DBA. The originalstructure design conditions are an internal pressure of 55 psig, a coincidenttemperature of 283
°F and a leak rate of 0.1% per day by weight at designtemperature and pressure. Actual containment conditions calculated to occurfollowing accidents are discussed in Chapter 14.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-3 of 1.2-11The containment is equipped with two independent, full-capacity systems forcooling by air recirculation or building sprays after the postulated DBA. Therecirculation system is designed to provide maximum containmentatmosphere mixing, however, fan operation is not credited in the analysis formixing. The cooling coils and fans are sized to provide adequate containmentcooling following a DBA with three of the four units in service on emergencypower. The building sprays supply borated water to cool and simultaneouslyremove some of the released fission products from the containmentatmosphere. The spray system is sized to provide adequate cooling with twoof the three containment spray pumps in service and the two shutdown heatexchangers in operation. Actual system capabilities and operatingrequirements for fans, coolers and sprays are discussed in Chapters 6 and 14.The pumps initially take suction from the safety injection and refueling waterstorage tank. When this supply is depleted, the suction is transferredautomatically to the containment sump. By the onset of this recirculationphase, sodium tetraborate is dissolved in the sump solution to neutralize theboric acid.
1.2.4NUCLEAR STEAM SUPPLY SYSTEM (NSSS)The NSSS consists of a pressurized water reactor with two closed loops. Theprincipal components and supporting systems of the NSSS are the reactorvessel, internals, control rods, control rod drives, slightly enriched fuel, two"U" tube steam generators, four primary coolant pumps, primary systempiping, pressurizer, quench tank, Chemical and Volume Control System,Safety Injection System, nuclear and process instrumentation, and theReactor Protective System.The NSSS uses chemical shim and control rods for reactivity control andsupplies steam to a four-flow, tandem-compound, hydrogen-cooled turbinegenerator.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-4 of 1.2-11The NSSS is expected to have adequate margin to obtain an ultimate outputof 2,650 MWt. The steam and power conversion equipment is designed for amaximum expected gross capability of 865 MWe. See Table 1-2 forequipment design. The Primary Coolant System operates at a nominalpressure of 2,060 psia. The primary coolant enters the upper section of thereactor vessel, flows downward between the reactor vessel shell and the corebarrel, and passes through the flow skirt and into the lower plenum where theflow distribution is equalized. The coolant then flows upward through the coreremoving heat from the fuel rods, exits from the reactor vessel, and passesthrough the tube side of the two vertical "U" tube steam generators whereheat is transferred to the secondary system. Two primary coolant pumps persteam generator return the primary coolant to the reactor vessel.
1.Reactor Vessel and InternalsThe reactor vessel and its removable hemispherical closure head arefabricated from carbon steel and are lined with 308/309 stainless steel.In the areas of internal attachments, the interior is clad with Ni-Cr-Fealloy. A fixed hemispherical head is attached to the lower end of theshell. The reactor vessel is supported on three pads welded to theunderside of the coolant nozzles.The reactor core is supported from the reactor vessel flange and isfueled with uranium in the form of slightly enriched UO 2 pellets.Zircaloy-4or M-5 tubing is used for the fuel cladding. The corecontains 204 fuel bundles and 45 control rods.A three-to-four batch, mixed central zone fuel management plan isemployed and a further reduction in nuclear peaking is obtained bylocal enrichment zoning within the bundles. Boric acid dissolved in thecoolant is used as the neutron absorber to provide long-term reactivitycontrol. In order to reduce the boric acid concentration required at thebeginning of the fuel cycle, and thus to make the moderator coefficientof reactivity more negative, mechanically fixed, burnable poison rodsare utilized.
2.Steam GeneratorsThe two steam generators are vertical shell and "U" tube units (seeTable 4-4).The steam generated in the shell side of the steam generator flowsupward through moisture separators which reduce its moisture content.All surfaces in contact with the primary coolant are either stainlesssteel or Inconel in order to maintain primary coolant purity.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-5 of 1.2-11 3.Primary Coolant PumpsThe coolant in the primary loop is circulated by four primary coolantpumps of the single suction centrifugal type. The pump shafts aresealed by mechanical seals. The seal performance is monitored bypressure and temperature sensing devices in the seal water circulationsystem.4.Primary System PipingEach of the two loops which make up the Primary Coolant Systemconsists of one 42-inch ID pipe and two 30-inch ID pipes. The largerpipe carries the water from the reactor to the steam generator. Theflow from the steam generators is pumped to the reactor through the30-inch ID pipes.
5.Pressure Control SystemThe pressure in the Primary Coolant System is controlled by regulatingthe temperature of the coolant in the pressurizer, where steam andwater are held in thermal equilibrium. Steam is formed by thepressurizer heaters or condensed by the pressurizer spray to reducepressure variations caused by expansion and contraction of theprimary coolant due to primary system temperature changes.Overpressure protection is provided by spring-loaded safety valvesconnected to the pressurizer. The discharge from the pressurizersafety valves is released under water in the pressurizer quench tank,where it is condensed and cooled. In the event that the dischargedvolume of steam exceeds the capacity of the quench tank, the tankrelieves via a rupture disc to containment.
6.Reactor ControlThe reactor is controlled by a combination of 45 control rods anddissolved boric acid in the primary coolant. Forty-one of the controlrods are full length, and four partial-length rods are also provided. Thepart-length rods are maintained in the fully withdrawn position duringreactor operation and do not insert following a reactor trip.Boric acid addition or removal is used for reactivity changes associatedwith major changes in water temperature during start-up andshutdown, fuel burnup and xenon variations. Additions of boric acidalso provide an increased shutdown margin during initial fuel loading,refuelings and approaches to cold shutdown condition. The boric acidsolution is prepared in a boric acid batching tank, stored in two storagetanks, and maintained at a temperature sufficient to preventprecipitation. The tanks are connected to the charging pumps throughlocked open manual and automatic valving.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-6 of 1.2-11Control rod movement provides changes in reactivity required forpower changes or for shutdown to a hot condition. The control rodsare made of a silver-indium-cadmium alloy clad with stainless steelwelded into a cruciform configuration. They are actuated by controlrod drive mechanisms mounted on the head of the reactor vessel. Thecontrol rod drive mechanisms, which are rack-and-pinion units, aredesigned to permit rapid insertion of the control rods into the reactorcore by gravity.
7.Chemical and Volume Control SystemThe purity of primary coolant is controlled by continuous purification ofa portion, "letdown," of the total primary coolant volume. Coolant isremoved from the primary system and is initially cooled in theregenerative heat exchanger. The coolant letdown is then reduced inpressure by orifices and letdown back pressure valves and again intemperature as it passes through the letdown heat exchanger. Theletdown then flows through one of three demineralizers wherecorrosion and fission products are removed through a filter which trapsparticulate matter in the effluent from the demineralizer. It is thensprayed into the volume control tank.The volume control system automatically controls the rate and amountof coolant returned to the Primary Coolant System to maintain thepressurizer level within a control band and thereby compensates forchanges in volume due to primary coolant temperature changes. Thevolume control tank is sized to accommodate primary coolant inventorychanges resulting from load changes from hot standby to full power.This mode of operation, using the volume control tank as a surge tank,decreases the quantity of liquid and gaseous waste which otherwisewould be generated.8.Chemical TreatmentPrimary system makeup water is taken from the demineralized waterstorage system and from the concentrated boric acid tanks. Themakeup water is pumped through the regenerative heat exchanger intothe primary loop by the charging pumps.Bleed from the primary system during a boron concentration reductionis routed to the radwaste liquid receiver tanks for processing throughthe Radwaste System before reuse in the Plant or disposal to the lake.Chemical injection equipment is provided for the addition of corrosioncontrol chemicals to the primary loop water. Hydrogen is added toprimary coolant for oxygen scavenging through the volume control tank.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-7 of 1.2-11Depleted zinc ions are added to primary coolant through the ZincAddition System for the removal of radioactive cobalt ions from PCSpiping (inner walls). Removal of the radioactive cobalt ions reducesdose to personnel from PCS piping.
9.Nuclear Control and Instrumentation a.Nuclear Plant ControlThe reactor control system provides for start-up and shutdownof the reactor and for adjustment of the reactor power inresponse to turbine load demand. The NSSS is capable offollowing a ramp change from 15% to 100% power at a rate of5% per minute and at greater rates over smaller load changeincrements up to a step change of 10%. This control isaccomplished by manual rod motion. A temperature computingstation calculates the reactor average temperature and areference temperature value corresponding to turbine power.The reactor average coolant temperature and the referencetemperature values are displayed to operators who manuallyadjust coolant temperature by moving control rods. Regulationof the primary temperature in accordance with this programmaintains the secondary steam pressure and matches reactorpower to load demand.b.Reactor Neutron MonitoringThe nuclear instrumentation consists of excore and incore fluxmonitoring chambers. Eight channels of excore instrumentationmonitor the neutron flux and six of the eight channels providereactor protection signals during start-up and power operation.Two of the channels follow the neutron flux through the start-up range.The incore monitors consist of rhodium neutron detectors and athermocouple. This system provides information on neutron fluxand temperatures in the core.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-8 of 1.2-11 c.Reactor Protective SystemThe reactor parameters are maintained within acceptable limitsby the inherent characteristics of the reactor, by the control rodsystem, by boron control and by the operating procedures.Departures from these limits are indicated audibly and visuallyin the control room. A Reactor Protective System initiatesreactor shutdown if selected values of parameters areexceeded. The protective system is divided into four channels.Each channel receives trip signals from sensors when therelevant parameter values are exceeded and a two-of-fourcoincident logic system sends a "deenergize" signal to thecontrol rod drive mechanism clutch power supplies.The control rods are released and the reactor is shut downwhen the clutch power supplies are deenergized. Redundantsensors are provided for the reactor shutdown functions so thatfailure of any one sensor does not prevent a reactor trip.
d.Other Safety-Related Protection and Control SystemsWhile the Reactor Protective System protects the reactor coreand the engineered safeguards controls protect against a Lossof Coolant Accident (LOCA), other safety-related Class 1Econtrol and instrumentation systems are provided to allow asafe shutdown of the Plant, assure decay heat removal andprotection of fluid systems boundaries. Such systems arereactor shutdown controls, primary coolant and other liquidboundaries overpressure protection, automatic auxiliaryfeedwater initiation and containment hydrogen control.
e.Process InstrumentsCritical primary system parameters are monitored by redundantchannels. Additional temperature, pressure, flow and liquidlevel monitoring is provided as required to keep the operatingpersonnel informed of Plant conditions and to provideinformation from which Plant processes can be evaluated orregulated. The plant gaseous and liquid effluents are monitoredfor radioactivity. The levels are displayed and recorded andhigh values are annunciated.Area monitoring stations are provided to monitor radioactivity atselected locations around the Plant. High-pressure or high-radiation conditions within the containment building initiatecontrol action to isolate the containment.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-9 of 1.2-1110. Safety Injection SystemFour safety injection tanks are provided, each connected to one of thefour reactor inlet lines. Each tank has a volume of approximately2,000 cubic feet containing approximately 1,000 cubic feet of boratedwater at a concentration of 1,720-2,500 ppm and pressurized byapproximately 1,000 cubic feet of nitrogen at approximately 200 psia.In the event of a large Loss of Coolant Accident, the borated water isforced into the Primary Coolant System by the expansion of thenitrogen. The water in three tanks will adequately refill and reflood theentire core. In addition, borated water will be injected into the reactorvessel to cool the core via the same nozzles used by the SI tanks bytwo low-pressure and two high-pressure injection pumps taking suctionfrom the 285,000-gallon safety injection and refueling water storagetank (SIRW). For maximum reliability, the designed capacity from thecombined operation of one high-pressure and one low-pressure pumpprovides adequate injection flow for any Loss of Coolant Accident.Upon depletion of the storage tank supply, the high-pressure pumpsuction automatically transfers to the containment sump and thelow-pressure pumps are shut down. One high-pressure pump hassufficient capacity to maintain the core water level at the start ofrecirculation. In the event of a DBA, at least one high-pressure andone low-pressure pump would receive power from the emergencypower sources. Both high- and low-pressure injection pumps arelocated outside the containment building to permit access for periodictesting during normal operation. The pumps discharge into separateheaders which lead to the containment. Test lines are provided topermit running the pumps for test purposes during Plant operation.11. Shutdown Cooling SystemThe Shutdown Cooling System consists of a forced circulation heatremoval loop which includes the low-pressure safety injection pumpsand the shutdown heat exchangers. The system is designed totransfer heat from the Primary Coolant System to a closed loop coolingsystem during normal shutdown, refueling and maintenanceoperations.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-10 of 1.2-11Emergency shutdown cooling during a loss of normal and standbyelectrical power is accomplished by allowing natural circulation of theprimary coolant to transfer heat from the core to the steam generators.The steam that is generated is released to the atmosphere as required.One of two auxiliary electric-driven feedwater pumps operating fromeither emergency diesel generator, or an auxiliary turbine-drivenfeedwater pump, supplies feedwater to the steam generators duringthis period. A 100,000-gallon supply of demineralized water availableto these pumps is sufficient for eight hours of decay heat removal. Inaddition, the Plant has the capacity for long-term cooling incorporatingthe ability to flush the reactor core and prevent post-LOCA boric acidprecipitation.12. ShieldingShielding is provided so that radiation exposure of personnel will notexceed the recommended limits of 10 CFR, Part 20. The design ofradiation shielding is dependent both on the extent of access requiredto a particular location and on the sources of radiation adjacent to thatlocation.The control room is shielded to permit continuous occupancy followingany accidental release of radioactivity in the containment.
1.2.5TURBINE GENERATORThe turbine is an 1,800 r/min tandem-compound unit with external moistureseparation and live steam reheating. The double-flow high-pressure elementexhausts to two double-flow low-pressure elements through moistureseparators and reheaters. The low-pressure elements discharge to the maincondenser and the condensate is returned to the steam generators throughsix stages of feedwater heating. Steam is extracted for feedwater heatingand for two auxiliary turbines which drive the two half-sized steam generatorfeed pumps.The feedwater cycle is of the closed type with deaeration effected in thecondenser. Feedwater heaters are arranged in two parallel trains, each withone high-pressure and five low-pressure heaters. Separate feedwaterregulating valves control the flow to each of the two steam generators.The 1,800 r/min, hydrogen inner-cooled generator is rated at 955,000 kVA at75 psig hydrogen pressure, 0.85 power factor and 0.
62 short circuit ratio.Field excitation is provided by a brushless exciter directly coupled to the generator shaft.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 30SECTION 1.2Page 1.2-11 of 1.2-11The turbine generator has a guaranteed capability of 811,776 kWe gross at1.8 inches Hg absolute back pressure and 0.25% makeup with inlet steamconditions of 735 psia and 509°F. The maximum calculated capacity of theturbine generator is 865 MWe gross.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 21SECTION 1.7Page 1.7-1 of 1.7-2 1.7RESEARCH AND DEVELOPMENT REQUIREMENTSThe design of the Palisades Plant is based upon concepts which have beensuccessfully incorporated in pressurized water reactor systems. However,certain Palisades specific Combustion Engineering development tests havebeen performed and are listed below. These tests were completed prior toinitial Plant start-up.
1.7.1FLOW MIXING AND FLOW DISTRIBUTIONTests have been run to measure the flow mixing factor. Dye dispersion ratewas measured in a series of full-scale and larger than full-scale mock-ups ofvarious fuel bundle flow channel configurations. These tests were run in acold-water test loop.A larger than full-scale model of the Palisades bundle inlet region has beentested in a cold-water flow loop to determine the effect of minor flowmaldistributions due to inlet structure nonuniformities, and to verify theeffectiveness of certain steps taken to improve inlet flow.
1.7.2CONTROL ROD TESTSA series of tests were run to demonstrate the adequacy of the control rod andits guidance system. Cold-water flow testing of a slightly underscale model offour bundles and a cruciform control rod was performed. These tests wereconducted with mechanical misalignments exceeding design values.In addition to the cold-water tests, a test program has been performed using afull-scale model, including a prototype mechanism under reactor conditions offlow, temperature and pressure in the CE Utility Reactor Components TestFacility at Windsor. The purpose of this program was to assess the effects ofmechanical misalignments, of thermal distortions which have been measuredon model fuel bundles and on a prototype control rod, of cross flow and ofupper limit conditions of axial flow and system pressure.A series of mechanical tests have been run on structural components of theAg-In-Cd control rod blade.
1.7.3CONTROL ROD DRIVE MECHANISMSAn extensive development program has been completed on the control roddrive mechanisms. This program has included up to 130,000 feet of travel onvarious components and 350 full-height drops. The production mechanismdesign incorporates improvements derived from experience gained on thisprogram.
FSAR CHAPTER 1 - INTRODUCTION & GENERAL DESCRIPTION OF PLANTRevision 21SECTION 1.7Page 1.7-2 of 1.7-2 1.7.4FUEL BUNDLE DESIGNCombustion DesignCold-water flow-induced vibration tests on fuel rods and subassemblies andmechanically induced vibration tests in air on model bundles have beencompleted. An extensive hot flow test program, including the effects of forcedcross flow, has been completed using essentially full-length, though not fullcross-section, bundles. Total time at reactor conditions (or conditionsbelieved to be more severe) exceeded 13,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />. These tests have beensupplemented by a basic program on the mechanism of grid to fuel rod wearconducted in a static autoclave with mechanically induced relative motion.These tests substantiate the adequacy of the fuel bundle design for itsexpected service.In addition to this program, four full-scale model fuel bundles were tested byCombustion Engineering at reactor conditions (or more severe conditions) inthe Utility Reactor Components Test Facility. Beginning with the second fuelcycle, Combustion Engineering fuel has not been used.Current Fuel DesignComparable developmental testings, as described previously, have also beenperformed by the current fuel vendor. Refer to Subsection 3.3.4.3 for details.
1.7.5REACTOR VESSEL FLOW TESTSA one-fifth scale model of the reactor vessel and its internals has beenconstructed and subjected to airflow testing at the Battelle Memorial InstituteLaboratories at Columbus, Ohio. These tests have investigated flowdistribution, pressure drop and the tracing of flow paths within the vessel forall four pumps running and various part-loop configurations.