EJECTOR AIR REMOVAL SYSTEMS ENGINEERING DATA BULLETIN # PVS ARS PAGE 1 OF 5

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1 BULLETIN # PVS ARS PAGE OF 5 GENERAL Air Removal Systems generally consist of dual 00% (twin-element) ejecrs, single 00% surface-type inter- & aftercondensers, suction & discharge isolation valves for each stage and interconnecting vacuum piping. These systems are designed meet Heat Exchange Institute () and specific industry standard requirements as follows: Requirements Air removal ejecrs designed meet specified requirements must handle the recommended air leakage, saturated with water vapor at Hg Abs and 7½ F below the operating temperature of the condenser served by the ejecr. These systems as described above are arranged allow operation with one spare set of ejecr stages, installed and ready operate. Industry Standard Requirements Air removal ejecrs designed meet industry standards should handle the air leakage specified, saturated at the operating pressure and 7½ F below the operating temperature of the condenser served by the ejecr. If air leakage is not specified, use the recommended value but not the recommended operating pressure of HgA. Size for Hg below the design operating pressure. Single-element units are available. STANDARD MATERIALS OF CONSTRUCTION EJECTORS INTERCONNECTING VACUUM PIPING Steam Chest: Carbon Steel Pipe & Fittings: Carbon Steel Steam Nozzle: 0SS VACUUM VALVES (Butterfly-Type) Suction Chamber: Carbon Steel / Disc: Nodular / Cast Iron Diffuser: Carbon Steel Elasmers: Buna CONDENSERS STEAM PIPING Shell: Carbon Steel Steam piping, valves & strainers are suitable for the design Water Boxes: Carbon Steel motive pressure and temperature of system motive steam Tube Sheets: Carbon Steel supply. Standard is Sch. 80 pipe (A06) with,000# fittings Tubes: 04LSS and 800# class valves (A05). Baffles: Carbon Steel

2 BULLETIN # PVS ARS PAGE OF 5 Large steam condensers serving turbines require air removal equipment maintain the vacuum on the main condenser. The design characteristics of air removal equipment are outlined in the Heat Exchange Institute Standards for Steam Surface Condensers. Unique Systems has combined the requirements of with cusmer specifications and has developed standard air removal equipment with both single- & twin-element ejecr systems serve commercial and power industry requirements. In addition the air removal ejecr needed maintain a vacuum on the condenser, a rapid evacuation (hogger) single-stage ejecr is usually required during start-up remove air from the turbine, piping and condenser shells. In cases where start-up steam is not available, common with combined-cycle power systems, consult with Unique Systems for information on alternatives including liquid ring vacuum pump hogger exhausters. SELECTION PROCEDURE How properly select single- or twin-element ejecr systems for air removal service is demonstrated in the example that is presented with the tables described below. TABLE Lists the air leakage quantities corresponding the given steam flow, ejecr sizes and steam requirements for various condenser pressures. Twin-element systems require two ejecrs of each size in the chosen system. TABLE Lists the properties of inter- & aftercondensers used on single-element air removal ejecr packages. For air removal capacities of 7.5 SCFM, a choice of separate or combined shells for inter- & aftercondensers is available. TABLE Lists the properties of inter- & aftercondensers used on twin-element air removal ejecr packages. Limited choices of separate or combined shell for the condensers are available. TABLE 4 Lists evacuation data for hogger ejecrs. Non-standard hoggers sized for volume and evacuation time are also available.

3 BULLETIN # PVS ARS PAGE OF 5 SELECTION PROCEDURE (EXAMPLE) Select Twin-Element Air Removal Package serve a condenser using the following criteria Condenser Steam Flow: Motive Steam Pressure: Ejecr Design Suction Pressure: 0,000 #/Hour 00 PSIG (Dry & Saturated) Hg Abs Unit Size (Table ): CC Twin-Element Steam Consumption (Table ): 80 #/Hour per Element Surface Area (Table ): 60 Ft² or 5 Ft² (Alternate) Surface Area (Table ): 0 Ft² or 4 Ft² (Alternate) * Water Consumption: 40 GPM Water Velocity:.5 Feet/Second Water Velocity:.7 Feet/Second Alternate Water Velocity: 0.65 Feet/Second Alternate Water Velocity:.47 Feet/Second * Note: This example is based upon using cooling water for the inter- & aftercondensers. Please consult Unique Systems for systems using condensate as the cooling medium. TABLE : AIR LEAKAGE RATES STEAM FLOW LIMITS (#/Hour) 0 5,000 5,00 50,000 50,00 00,000 00,00 50,000 50,00 500,000 LEAKAGE RATE (SCFM) 70 F Air CONDENSER PRESSURE (Inches Hg Abs) * Please consult Unique Systems for steam pressures other than 00 PSIG. NOMINAL STEAM CONSUMPTION PER ELEMENT (#/Hour) 00 PSIG Steam * SIZE CC 5CC 5CC 5CC CC CC CC CC CC 4C5C 4C5C C5C C5C C5C C5C C5C 6C5C 4C5C 4C5C C5C C5C C5C C5C

4 BULLETIN # PVS ARS PAGE 4 OF 5 TABLE : SINGLE-ELEMENT SURFACE-TYPE INTER- & AFTERCONDENSERS Size Leakage (SCFM) Comments Surface (Ft ) No. Surface (Ft ) No. Min. Water Flow Max. Water Flow TABLE : TWIN-ELEMENT SURFACE-TYPE INTER- & AFTERCONDENSERS Size Leakage (SCFM) Comments Surface (Ft ) No. Surface (Ft ) No. Min. Water Flow ** Max. Water Flow * * ½ ½ ½ ½ * * * * * * * * ,50 * * * * * Information for 7.5 & 0 SCFM systems and larger can be obtained from Unique Systems for specific applications. ** Based upon using cooling water for inter- & aftercondensers. Designs using condensate as cooling medium also available ½ ,50 GPM = Steam Flow Main Condenser (#/Hour) 500 ½ ½ ½ ½

5 BULLETIN # PVS ARS PAGE 5 OF 5 TABLE 4: EVACUATOR DATA (HOGGER EJECTORS) STEAM FLOW LIMITS (#/Hour) Capacity (#/Hour) Air at 5 Hg Abs EVACUATOR DATA Steam Consumption (#/Hour) 00 PSIG Steam * Ejecr Size 0 75, E 75,00 50,000,50,650 4E 50,00 750,000,700,00 6E 750,00,000,000 4,050 4,940 6E,000,00+ Higher 5,550 6,700 8 x 8 * Please consult Unique Systems for steam pressures other than 00 PSIG. Non-standard hoggers sized for volume and evacuation time are also available. If steam is not available during plant start-up, consult Unique Systems for alternatives including liquid ring vacuum pump hoggers. NOTICE OF PROPRIETARY RIGHTS: This brochure, drawings and/or information shown, is the sole property of Unique Systems, Inc. Receipt or possession thereof does not confer of transfer any right make, copy, manufacture and/or sell this or these devices by method shown. The information contained in this document is subject change at any time and without prior notice. No warranties or guarantees of any kind are made or implied by any of the content of this document. UNIQUE SYSTEMS and its logo are registered trademarks of Unique Systems, Inc. 009 Unique Systems, Inc.