Innovative Resin Technologies for. World Class PWR Chemistry Operations. September 4 & 5, 2008

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1 Innvative Resin Technlgies fr Wrld Class PWR Chemistry Operatins September 4 & 5, 2008 Intrductin Graver Technlgies principal custmer is the pwer utility. We are fcused n the business and supprt fr thse utility custmers. As such ur Sales, Custmer Service, Technical, Develpment, and Manufacturing grups are rganized t effectively address this unique business and the special applicatins that are vital t the industry. Graver Technlgies is the riginal prvider f bead & pwdered resins and filters, alng with being a part f the riginal cmpany that supplied much f the capital equipment fr wrldwide cndensate plishing. As the acknwledged leader in the innvatin f prduct applicatins & develpment fr utility resin and filter systems, Graver cunts mre than 30 patents in the utility field. Graver has initiated ver 30 unique prducts & systems that directly affect the utility business, particularly in the area f cndensate plishing. These include the inventin f the Pwdex resins and Ecdex precat prducts, the intrductin f pre-aminated catins fr blwdwn systems, the intrductin f the new ultra-lw chlride anin t allw peratin f the catin past the amine break at high ph, and many thers as well as new innvatins under develpment. New prducts and new applicatins are vital t the cntinued imprvement in utility perating systems. We cntinue t fcus ur abilities t prvide the latest in resin technlgical advancements t ur custmers and are pleased t discuss sme f these innvatins.

2 Ultra Lw Chlride Anin Resin Lw chlride anin exchange resins have been available fr many years. These anin resins are cmmnly classified as Nuclear Grade and many nuclear plant specificatins invke this requirement. Prducts meeting this lw chlride level are generally available frm mst reputable in exchange suppliers and manufacturers. As cndensate plishing perating requirements becme mre stringent, lwer chlride levels are desired. Graver Technlgies recgnized the need and wrked clsely with a US PWR plant t develp a new anin exchange resin prduct that fulfilled this need and has led t significant peratinal imprvements. Gravex GR 1-9 US Ultra, sets the standard with a new state-f-the-art level in ultra lw chlride perfrmance. Imprvements are experienced with PWR cndensate plisher peratin. With nearly an rder f magnitude lwer chlride level than the nuclear grade resins, the unique GR 1-9 prduct is perfrming as n anin exchange resin has previusly. The ultra lw chlride anin allws the catin resin t be perated in the amine frm. The new ultra lw chlride anin resin als ffers imprved peratin in ther high purity applicatins including steam generatr blwdwn, fuel pl, and CVCS demineralizers. Cndensate Applicatin Graver Technlgies wrked jintly with Dminin Nuclear Cnnecticut at the Millstne site in Waterfrd, Cnnecticut. Bth perating plants are seawater-cled, pressurized water reactr (PWR) units. At Millstne, Unit 2 is an 895 MWe Babcck & Wilcx PWR and Unit 3 is an 1154 MWe Westinghuse PWR. Bth PWR s perate as nn-mlar rati plants. Millstne s gal was t reduce crrsin prduct (especially irn) transprt t the steam generatrs by increasing the amine cncentratin. Prblems that ensue frm such transprt include internal surface fuling, reduced heat transfer, decreased steam pressure, and ultimately increased lcalized crrsin, cmmnly called Inter Granular Stress Crrsin Cracking (IGSCC). Cnversely, minimizing irn transprt extends steam generatr life which is crucial since the cst f replacing a steam generatr can run mre than $300 millin. Like many thers in the industry, Millstne utilizes ethanlamine (ETA) t elevate ph f the secndary side cndensate chemistry which minimizes feedwater crrsin transprt. MIllstne reprted n a number f initiatives undertaken t address the irn transprt prblem thrugh ph-related peratinal changes including higher efficiency regeneratins, higher capacity strngly acidic catin resins, air injectin int the cndensate, and amine frm peratin f the cndensate plishers. Nne f the effrts achieved the gal f acceptable peratin at higher amine cncentratins. In the summer f 2002, Millstne cnducted bench scale testing f a strngly acidic catin resin fully cnverted t the ETA frm. This test utilized a mixed bed f the ETA frm catin and a hydrxide frm anin t determine impurity remval efficiency during a simulated seawater in-leakage t the cndenser. Successful results in this bench test cnvinced Millstne persnnel t evaluate the perfrmance f an ETA/OH - mixed bed in ne cndensate plishing vessel f Unit 2 in the spring f Page 2 f 8

3 2004. During the 42 hur test f the mixed bed with the amine frm catin, chlrides in the steam generatr rse steadily frm 0.59 ppb t 3.50 ppb befre the test plisher was remved frm service. Even lw part-per-trillin (ppt) cncentratins f chlride in the effluent frm the plisher can result in part-per-billin (ppb) levels in the steam generatr due t the cncentratin factr ( ) at Millstne. Administrative limits n chlride as well as sdium, sulfate, irn, and cpper in the steam generatr are based n the INPO cndensate plisher index (CPI). Typically, steam generatr limits fr chlride in are set at lw r even sub-ppb levels. The elevated hydrxide cncentratin in the liquid phase in the ETA/OH - plisher eluted chlride frm the anin resin. It became imprtant t reduce the residual chlride levels n the anin t previusly unattainable levels. Millstne was unable t achieve the necessary chlride level with the techniques and highest quality regenerant chemicals available. At this pint, Millstne persnnel asked Graver Technlgies t help prvide a slutin. Graver Technlgies knew and understd well the need and hw t accmplish the desired results. Chlride specificatin fr typical cndensate grade anin is 0.5% f the in exchange sites and 0.1% fr a nuclear grade anin. Details f the extensive prcessing and test methdlgy needed were develped and implemented ver a perid f eighteen mnths, wrking clsely with Millstne t learn the effects f special regeneratin prcess steps. The result was the intrductin f Gravex GR 1-9 US Ultra. Typical nuclear grade anin resins can leach > 100ppt at the vessel utlet. The very first Gravex lt achieved < 30ppt. Subsequent lts have exhibited 20ppt, 14ppt, and < 10ppt when prcessing the higher ETA cntent, high ph cndensate streams. Steam generatr chlrides have remained within acceptable limits. Thus superir prtectin f the steam generatrs and assciated piping has been the result in additin t significant savings in chemical regenerant and amine chemical additin csts. The Gravex prduct is nw in regular use at Millstne and is installed in half f the beds in each unit. Plans are t install the anin in additinal beds as resin is replaced. The lngest service life Gravex bed is nw fur years ld and n the way t five years f service withut regeneratin, prcessing in excess f six billin gallns. This specialty anin has nw been installed in a secnd PWR with expectatins t replace cndensate anin in ther plants interested in imprving perfrmance and reducing csts. Benefits Imprved crrsin prduct transprt t steam generatrs Lwer irn levels and significantly reduces sludge buildup Extends life f steam generatrs Lwest chlride ingress t steam generatrs Reduced attack n metallurgy thrughut the cndensate system Cndensate plisher peratin withut regenerating the resins Current experience is fur years and expect t achieve five years withut regeneratin f either the anin r catin cmpnents Nrmal practice fr standard prducts is t regenerate anin resin several times per year and catin resin as ften as weekly Page 3 f 8

4 Chemical regenerant cst savings N need fr chemicals fr five years r mre per bed prviding significant cst savings Reductin in the amunt f amine that is added t the cndensate cycle t small dsages fr fine ph adjustments Significant annual cst savings Reduced manpwer requirements nrmally needed t perfrm cndensate plisher regeneratins and mnitr large amine dses Ultimate lw chlride level in ther critical plant applicatins such as CVCS, blwdwn demineralizers, and fuel pls Lw Sulfate Leakage Catin Resin A lw sulfate leakage catin exchange resin may be the perfect cmplement t the ultra lw chlride anin. As steam generatr and reactr cntaminant limits cntinue t becme tighter, the need fr superir quality in exchange resins has never been mre imprtant. Many requirements fr the resins and their cntaminants have als been tightened and gd quality catins are available. Gd quality hwever is n lnger sufficient and superir quality will be needed by mst perating nuclear plants. One f the majr areas t address is sulfates frm catin resins. Strngly acidic catin exchange resins are sulfnated cplymers s the ptential fr sulfate leakage is inherent in the resins. During synthesis f the catin resins, lse plystyrene sulfnate ligmers ftentimes remain within the bead internal structure. These ligmers diffuse ut f the bead ver time and when rinsed thrugh a cndensate plisher bed will break dwn t sulfates in steam generatrs r reactrs. Small bead particles that pass thrugh the plishers wuld als cntribute t sulfate measurements. In additin, the base plymer degradatin/desulfnatin can ccur ver time and is accelerated by temperature and an xidizing envirnment. Leachable sulfate will als be the result f the degradatin althugh it is ften s slw and at such lw levels that it may nt be measurable, unless accelerated as described. Particulate leakage has been addressed by imprved strainer designs and by the reductin f fine particles in the resins as well as strict particle size specificatin limits. Tday, the particle issues are quite rare with a cnsistent gd quality resin. Leachable sulfates hwever are a different matter. The residual ligmers are ften present in all resins regardless f the riginal resin manufacturer. In additin t leaching int the cndensate, the sulfate bearing materials can ful the anin prtin f mixed beds leading t kinetic impairment and pr perfrmance. It is essential that the levels are reduced during pst manufacture prcessing. Graver Technlgies is expert in high level prcessing f all resins and is in the prcess f develping superir quality and perfrming catin exchange resins. Much f this experience cmes frm years f preparing high quality Pwdex resins fr cndensate plishing in precat filter demineralizers. Since grinding immediately expses the bead internals, the diffusin time fr any residual cntaminants is practically nil. The bead resins fr pwdered prductin Page 4 f 8

5 must be f the very highest quality. The prcess techniques are being refined t apply t cndensate and nuclear grade bead types. Several manufacturers cndensate plishing resins, including the high crss linked catins, are being evaluated. All as-received resins shw elevated leachable sulfate levels. Bth Graver Technlgies and nuclear plants wuld receive these same quality resins frm base manufacturers. Preliminary results shw significantly imprved sulfate levels after applying special prcessing t the catins. Lng term stability is als a part f the study t determine the ptimum prcess techniques. Prducts t be cmmercialized as lw sulfate Gravex catins cmplementary t the ultra lw chlride Gravex anin. Cmments and Benefits As manufactured catins can leach cntaminants that cntribute sulfate t the cndensate High crsslinked catins have been used t address sulfates Cndensate results are mixed Sme imprvement but lng term sulfate leakage is the same r smetimes nt quite as gd as standard crsslinked resins Fuel pl results are imprved as the resin better withstands perxide cntact Anin underlays have been used and reduce sme leachable sulfates but d nt address the surce and the underlays are disrupted during resin mvement fr regeneratin Catin resins shuld be fully prcessed t reduce leachable cntaminants Catins fully prcessed fr lw leachable sulfate are high value prducts Cannt be purchased n a lw price basis Benefits f fully prcessed catins Reduced sulfate bearing cntaminants in the feedwater Reduced fuling f anin cmpnent in mixed beds Imprved crrsin cntrl reducing the likelihd f IGSCC Extended anin life Reduced need r eliminatin f anin underlays Page 5 f 8

6 High Perfrmance Blwdwn Demineralizer Mixed Beds PWR plants are beginning t depend mre n the steam generatr blwdwn demineralizers (SGBD) fr cntrl f cycle chemistry. As issues arse with anin kinetic impairment in sme plants using ETA fr cndensate chemistry, several plants used the cndensate plishers nly fr start ups, cndenser leaks, r ther anmalus situatins. As custmers were changing their mde f peratin, the SGBD in exchange mixed bed perfrmance became even mre imprtant. Graver Technlgies develped several specialty mixed beds specifically fr this applicatin. The amine is remved frm the cycle by the catin prtin f the mixed bed. In sme cases plants emply fully laded catin beds preceding the mixed beds. Other plants prefer t use catin rich mixed beds. Tw specialty mixed beds, Gravex GR 3-15 and GR 3-30, were develped fr specific custmer requirements and have perfrmed well in the applicatin three catin t ne anin by vlume and by capacity. Other suppliers have been unable t prepare the specialty mixed beds while maintaining unifrm mixing and prduct stability. Graver Technlgies has the capabilities and the willingness t listen t and understand custmers needs and fllw thrugh with slutins that imprve plant peratins. Benefits Made specifically fr high perfrmance PWRs High capacity fr crrsin prducts and amines Special blending equipment and prcess t insure unifrmity much tighter catin t anin rati tlerances than ther manufacturers standard mixed beds Cmpnent selectin and prcessing t insure maximum stability Lnger bed life because f the high catin ratis Small primary t secndary leakage prtectin reductin f radinuclides Amine Frm Catin Resins fr Cndensate Plishing Systems Nuclear PWR cndensates perate at elevated ph, ften 9.0 t 9.3 r higher, t minimize crrsin transprt. Varius amines r cmbinatins f amines may be used t maintain the elevated ph. These include ammnia, hydrazine, ethanlamine (ETA), and mrphline amng thers. As mre amine is added, the higher the resulting ph. Cndensate plishing system mixed beds are typically laded with strngly acidic catin resin in the hydrgen frm and the strngly basic anin resin in the hydrxide frm (H + /OH - ). Mst cmmn catin t anin ratis used are either a 1:1 stichimetric mix r a 2:1 vlume mix. Cmbined vlumes fr a system range frm 1,000 (> 28m³) t mre than 2,000 (~ 57m³) cubic feet. In all cases there is a Page 6 f 8

7 significant amunt f hydrgen frm catin that will remve amines up t the resin s capacity. The amunt f amine remved by the catin resin must be replenished by injectin int the cndensate after the cndensate plishers. Annual amine csts may be several $100,000 dllars per unit. Graver Technlgies began ffering ammnium frm pwdered resin mre than 40 years ag t maintain fssil plant cndensate ph. Tday 10,000s f cubic feet f hydrgen frm catin are cnverted t the ammnium frm at Graver s NJ site using a special prprietary prcess with high purity regenerant chemicals and rinses. The ammnium frm catin is grund and used in several pwdered resin prducts. Graver Technlgies had the knwledge, experience, and capability t manufacture the high-quality mrphline frm catin prducts needed t imprve the perating perfrmance f a large, tw-unit PWR plant. A mrphline frm pwdered catin alng with hydrxide frm pwdered anin are used in the cndensate system s precat filter demineralizers. Extremely lng runlengths are btained and mst f the cycle chemistry is cntrlled by the Steam Generatr Blwdwn Demineralizers (SGBD). Specialty Gravex prducts utilizing mrphline frm catin were develped fr the SGBDs and have been used rutinely fr abut 15 years. Cycle chemistry at this 2 x 1,200 MWe PWR is amng the best in the wrld. Mrphline frm catin (GR 2-5 SG (M)) is fllwed by a mixed bed als with the mrphline frm catin cmpnent (GR 3-22 SG (M)). Abut 1,000 cubic feet (28 m³) ttal are used annually. The prducts are made with a special macrprus catin and blended with a high capacity gel anin fr the mixed bed. The mrphline frm macrprus catin is selective fr sdium and helps maintain excellent chemistry parameters. Mrphline cncentratin and ph are maintained and injectin f additinal mrphline is reduced t a minimum, saving significant chemical csts. Catin resin in the ethanlamine (ETA) frm is a new ffering. It can be used in the same manner as the mrphline frm Gravex prducts with the catin fllwed by the mixed bed in the SGBD. Similar perfrmance and advantages are expected. The ETA frm catin may als be used in deep bed cndensate systems. This is already being dne as described in the Ultra Lw Chlride Anin sectin. Cmbining several f these new prcess treatment cncepts, the catin can be prcessed t achieve the lwest pssible sulfate value, specially regenerated t the ETA frm, and then used with the Ultra Lw Chlride Anin t prvide perhaps the ultimate cndensate plishing system fr PWRs. Benefits Reduced cnsumptin and cst f amine chemicals Mre stable amine cncentratin Simple ph maintenance Reduced crrsin prduct transprt Multi-year runlengths with reductin f regenerant chemicals and csts Page 7 f 8

8 Summary Gravex ultra lw chlride anin resin has lwest residual chlride level and minimal leachable chlride in high ph envirnments lwest steam generatr chlrides Gravex ultra lw chlride anin perates fr 4 years (expect 5 years) withut regeneratin, saving cnsiderable regenerant chemical and ther csts As manufactured catin resins exhibit measurable leachable sulfate - Gravex lw sulfate leakage catin is the perfect cmpanin t the ultra lw chlride anin fr the ultimate purity cndensate mixed bed Specialty Gravex SGBD mixed beds are unifrmly mixed, stable prducts with high capacity fr amines and crrsin prducts Amine frm Gravex catins fr use in SGBD and cndensate plishers t maintain cycle ph and reduce perating csts Amine frm catin used with ultra lw chlride anin allws higher amine cncentratins t reduce crrsin prduct transprt t the steam generatr reducing the resulting sludge buildup steam generatr life extended Page 8 f 8