INSTRUCTION MANUAL. Boil-Out TABLE OF CONTENTS SAFETY WARNINGS 2-3 RESPONSIBILITY 3 INTRODUCTION 3 PRE-BOIL OUT PROCEDURES 3-5 BOIL OUT PROCESS 5-9

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1 TABLE OF CONTENTS Description Page Number SAFETY WARNINGS 2-3 RESPONSIBILITY 3 INTRODUCTION 3 PRE-BOIL OUT PROCEDURES 3-5 BOIL OUT PROCESS 5-9 Indeck Keystone Energy, LLC Merwin Lane, Suite 100 Erie, PA Page 1 of 10

2 SAFETY WARNINGS The following personnel Warnings and equipment Cautions are to be followed when operating or servicing this steam generator. The page number following the warning gives their location in the manual. 1. Caution: Perform acid cleaning only under the close supervision of an experienced cleaning specialist, since this operation requires handling chemicals that could cause damage to the boiler. (Page 2) 2. Warning: Failure to properly clean new steam generating equipment can result in equipment failure and operational problems. (Page 3) 3. Caution: If a temporary gauge glass is used, make certain it is connected to show the water level in the drum during the flushing and boil out operations and that it is adequate for the boil out pressure. Improper connections or gauge glass can result in property damage or severe injury to personnel. (Page 5) 4. Warning: In no instance should the boiler be put into normal on line operation using a temporary gauge glass, since a failure could result in damage to the boiler and injury or death to personnel. (Page 5) 5. Warning: Temporary piping systems must be properly designed for boil out pressure and temperature conditions, properly supported and secured to prevent failure that could cause injury or death to personnel or equipment damage. (Page 6) 6. Caution: It is imperative that all systems be confirmed ready for boil out before injecting the boil out chemicals. Failure to do so may delay the boil out process allowing the chemicals to cause damage to the boiler components. (Page 6) 7. Caution: Austenitic alloys are highly susceptible to damage from boil out chemical solutions. They should not be allowed to come in contact with the solutions. (Page 6) 8. Warning: Avoid operating conditions that could cause a relief valve to operate during boil out. Highly alkaline solutions could cause personnel injury or damage to valve parts. (Page 6) 9. Warning: Extreme care must be taken by anyone handling boil out chemicals. Personnel must wear rubber suits, facemask and gloves for protection from the alkaline solutions. Chemicals may give off heat when dissolved. Follow the precautions that are provided by the chemical supplier for mixing and handling of boil out chemicals. (Page 7) 10. Warning: Never introduce raw boil out chemical directly into the boiler. Chemicals must be thoroughly mixed and dissolved with fresh water outside the boiler before injecting into the boiler. (Page 7) 11. Caution: DO NOT mix chemicals until ready to perform the boil out. Once boil out chemicals have been injected into the boiler, initiate boil out procedures within four (4) hours. Chemicals will settle out and concentrate if the boiler water is allowed to sit and could damage pressure parts. (Page 8) 12. Caution: Whenever fuel firing is curtailed, the fans should remain in operation to purge the unit of any unburned combustibles. (Page 8) 13. Warning: Failure to open vents while draining the unit will result in a vacuum being developed within the unit. Attempting Page 2 of 10

3 to open manways and handholes under vacuum may cause serious injury or death to personnel. (Page 8) performed without a direct specific need determined from a thorough inspection by an experienced specialist. RESPONSIBILITY The following outlines basic steps for development of a boiler pre-operational cleaning process. It is the responsibility of the plants operations and maintenance personnel to develop a concise cleaning plan based upon the installed hardware, its condition, associated balance of plant equipment, plant safety requirements, applicable codes and regulations, etc. WARNING: Failure to properly clean new steam generating equipment can result in equipment failure and operational problems. INTRODUCTION The safe long-term service of a boiler depends on maintaining waterside tube surfaces free of deposits that could hinder heat transfer. When a new boiler is to be started up, it is important to prepare the internal tube surfaces for operation by removing any greasy deposits left behind from fabrication and assembly. To remove these deposits, the boiler is boiled out with a strong alkaline water solution. Most boil out chemical formulations include detergents as a wetting agent and concentrated inorganic chemicals that dissolve and absorb grease and oil and break down deposits that could cause a problem if left in the boiler during normal operation. Caution: Perform acid cleaning only under the close supervision of an experienced cleaning specialist, since this operation requires handling chemicals that could cause damage to the boiler. PRE-BOIL OUT PROCEDURES Prior to boil out the unit should be inspected, pass a satisfactory hydrostatic test and flushed in accordance with the Pre-Service Inspection, Preparation For Service and Hydrostatic Test manual sections. Valves Several steps are needed to prepare a boiler for boil out cleaning. The setting of pressure part valves is critical to insure that these processes are performed properly. Table 1 provides valve settings for these processes. Even though alkaline chemicals in the boiler water during boil out will tend to loosen mill scale, if the boiler has rusted, or if some other condition has caused internal scale, the boiler may also have to be acid cleaned at start-up. Acid cleaning should not be Page 3 of 10

4 Table 1: Valve Position - Preparation for Service Valve Description Preparation Operation Filling Hydro Dry-Out Boil Out Waterwall Header Drains Closed Closed Closed Closed Lower Drum Drain Closed Closed Closed Closed Steam Drum Vent 1 Closed 2,5 2,5 Water Column Drains Closed Closed Closed Closed Water Column Isolation Valves Open Open Open Open Drum Safety Valves Closed Gagged Closed Closed Main Steam Stop Valve 3 Closed Open Open Main Steam Stop-Check Valve 3 Closed Open Open Main Steam ERV Isolation Valve Open Closed Open Open Main Steam ERV Valve Closed Closed Closed Closed Superheater Safety Valve Closed Gagged Closed Closed Superheater Start-Up Vent Valve Open Closed Open Open Superheater Drain Valve(s) Closed Closed Closed 6 Closed 6 Attemperator/Desuperheater Spray Water Shut-Off Closed Closed Open Open Attemperator/Desuperheater Spray Water FCV Closed Closed Open Open Feedwater FCV Closed 4 Closed Modulate Modulate Feedwater FCV Isolation Valves Closed Closed Open Open Feedwater FCV By-Pass Valve Modulate Open Closed Closed Economizer Isolation Valves Open Open Open Open Economizer By-Pass Valve Closed Closed Closed Closed Sweetwater Condenser Steam Supply Isolation Valve Open Open Open Open Sweetwater Condenser Condensate Isolation Valve Open Closed Open Open Sweetwater Condenser Water Inlet/Outlet Isolation Valves Open Open Open Open Chemical Feed Isolation Valve Closed Closed Open Open Continuous Blowdown Isolation Valve Closed Closed Open Open Continuous Blowdown Metering Valve Closed Closed Open Open Steam Sparging Isolation Valve Closed Closed Closed Closed Steam Sparging Temperature Control Valve Closed Closed Closed Closed Auxiliary Saturated Steam Connections Isolation Valves Closed Closed 7 7 Notes: 1. Open for saturated units. Closed for superheated units. 2. Open for saturated boilers. Closed after 5 PSIG drum pressure is attained for superheated units. 3. Open if no hydro. Closed if hydro is to be performed. 4. Modulate FCV if no by-pass is provided. 5. Drum and/or superheater vents modulated to build up system pressures. 6. Close once the drain water flow has gone to zero. 7. Open/Closed as required by the process Page 4 of 10

5 Reinstall safety and relief valves that may have been removed for a hydrostatic test. Remove safety and relief valve gags, hydro-plugs or blanking plates that may have been installed for the hydrostatic test. Water Gauge Glass If there are components in the steam drum gauge glass that could be damaged by flushing and boil out water (refer to specific gauge glass instructions), a temporary gauge glass should be installed. For example, a mica ported gauge glass will incur chemical damage from caustic boil out chemicals. Caution: If a temporary gauge glass is used, make certain it is connected to show the water level in the drum during the flushing and boil out operations and that it is adequate for the boil out pressure. Improper connections or gauge glass can result in property damage or severe injury to personnel. Warning: In no instance should the boiler be put into normal on line operation using a temporary gauge glass, since a failure could result in damage to the boiler and injury or death to personnel. BOIL OUT PROCESS The boil out procedure involves the firing of the boiler that contains highly alkaline, specially treated boiler water, at a low firing rate and at a steam pressure well below design pressure for several hours. Chemical formulations, steam pressure, and the duration of the boil out are to be determined by a water treatment specialist and approved by those persons responsible for boiler water treatment. Since the boiler will be fired during the boil out, it is important that the boiler operators and supervisors be familiar with all boiler and balance of plant equipment operating procedures to insure that there is no danger to personnel or to the equipment. Refractory Dry-Out Due to specific boiler construction features, a refractory dry-out of the unit may be required (refer to Preparation For Service ). In some instances the dry-out may be included as part of the boil out process. Contact EPTI for approvals. Equipment Operational Status The boil out process requires: Using start-up procedures to establish a normal drum water level. Insuring a means for control of water flow to the boiler and through the economizer, if provided. Having the following systems operational and ready to use: o o o o o Boiler auxiliary equipment such as fans and fuel firing equipment. Fuel firing control systems. Control systems for air, fuel and feedwater flow, furnace draft, steam temperature control. Manual control or remote manual, if it is part of the normal control system, as a minimum needs to be provided. Feedwater pumps, condensate pumps and all other equipment involved in providing feedwater to the boiler. Feedwater treatment system to deliver filtered, potable water. Normal makeup quality water is recommended, although not required since boil out chemicals will inhibit scale and the boil out process itself is a short term operation. Boil Out Water Disposal The highly alkaline boil out solutions of ph 11 or greater can present a disposal problem for waste treatment facilities, either in plant or of site. It may be necessary to temporarily connect the boilers drain system to a special holding tank or to inject neutralizing chemicals. Page 5 of 10

6 Warning: Temporary piping systems must be properly designed for boil out pressure and temperature conditions, properly supported and secured to prevent failure that could cause injury or death to personnel or equipment damage. Protection Of Operating Equipment There may be parts of the boiler system that could be damaged if they were exposed to highly alkaline boil out chemical solutions. Care must be taken to isolate these components or provide other protection from coming into contact with the boil out chemical solutions. Carbon steel and ferritic alloys although not susceptible to damage from the boil out chemicals under normal boil out conditions can in fact incur damage should the chemicals be allowed to reside for extended periods of time. Caution: It is imperative that all systems be confirmed ready for boil out before injecting the boil out chemicals. Failure to do so may delay the boil out process allowing the chemicals to cause damage to the boiler components. Filling With Water Refer to Preparation For Service instructions for procedures. Boil Out Chemicals The services of an experienced, competent water treatment specialist to provide required alkaline chemical formulation is recommended. Boil out chemical formulations are, in some cases, prepackaged mixtures of chemicals developed to remove grease and deposits and hold the materials in suspension for draining through the boilers blowdown and drain system. Indeck Keystone Energy, LLC. recommends preparing a boil out solution as follows: Trisodium Phosphate 40 Pounds/1,000 Gallons of Cleaning Solution Disodium Phosphate 10 Pounds/1,000 Gallons of Cleaning Solution Surfactant (Wetting Agent) 1 Pound/1,000 Gallons of Cleaning Solution Caution: Austenitic alloys are highly susceptible to damage from boil out chemical solutions. They should not be allowed to come in contact with the solutions. Boiler system components such as superheaters and economizers should be regarded in the same manner as during normal operation for the boil out process. Do not remove or disable any of the safety equipment, such as relief valves or safety interlock instrumentation. Warning: Avoid operating conditions that could cause a relief valve to operate during boil out. Highly alkaline solutions could cause personnel injury or damage to valve parts. Page 6 of 10

7 Mixing And Injecting Chemicals For Boil Out Warning: Extreme care must be taken by anyone handling boil out chemicals. Personnel must wear rubber suits, facemask and gloves for protection from the alkaline solutions. Chemicals may give off heat when dissolved. Follow the precautions that are provided by the chemical supplier for mixing and handling of boil out chemicals. Warning: Never introduce raw boil out chemicals directly into the boiler. Chemicals must be thoroughly mixed and dissolved with fresh water outside the boiler before injecting into the boiler. Caution: DO NOT mix chemicals until ready to perform the boil out. Once boil out chemicals have been injected into the boiler, initiate boil out procedures within four (4) hours. Chemicals will settle out and concentrate if the boiler water is allowed to sit and could damage pressure parts. Method I Mix chemicals outside the boiler in a separate container, which is provided with continuous fresh water flow to the mixing container and an outlet for a continuous flow to the boiler steam drum. Dissolve each chemical separately by slowly adding small amounts of the chemical to a large volume of water in the mixing container. Method II Mix each chemical separately with fresh water outside the boiler in a separate container to form a slurry. Lower the water level in the steam drum to below the opening, but not low enough to expose any tubes. Introduce the slurry to the steam drum through a chemical pump and connections or by hand through the manway opening. Final Check Before Boil Out If chemicals were added through the manway, close manways securely. Make certain all valves are in their proper positions for boil out. Make sure temporary gauge glass is installed. Be sure boiler is filled with water to the normal start-up operating level on the gauge glass. Fuel Firing For Boil Out It is preferred that natural gas is used as the fuel for boil out if available due to its high turndown capability and low soot properties. Fuel oil should be used as a second choice. For units that are fired solely on solid fuels, wood is preferred over coal as the fuel for boil out, or, a temporary gas or oil heat source may also be used, but such equipment, its location within the system and firing method must be approved by IKE. Coal, like oil, will cause acid dew point conditions to develop as a result of low firing rates and operating temperatures. For waste heat units whose heat source is process waste gas as well as heat recovery steam generators whose heat source is the flue gas from a combustion turbine generator, steps must be taken to limit the process or CTG gas flow and temperature or a temporary heat source may be used with IKE s approval for boiler out. Increasing Boiler Pressure Fire fuels at a low firing rate until steam is emitted from the vent valve(s). Allow a small amount of pressure to build up in the unit, check for leaks and tighten manways and gasketed handhole plates. Page 7 of 10

8 Carefully regulate the firing rate by manual control to slowly heat the unit. For units designed with rolled tube to drum connections, the rate of boiler water heat up should not exceed 100 F per hour. Feedwater flow should be regulated by manual control. Increase boiler pressure until the boil out pressure is reached. The pressure should be as high as possible (100 to 125 PSIG is recommended) while not exceeding the set pressure of the safety valves or 300 PSIG maximum. Partially close the vent valve to maintain pressure. Boil Out Procedure Control firing rate by using manual control or by operating through successive on/off cycles. Hold pressure in the boiler for 8 to 12 hours or for the time determined by the start-up consultant or water treatment specialist. Do not blow down the unit during this period. After the initial baking time has expired, shut down the unit. This requires shutting off burners or heat source from process or CTG s or banking solid fuel boil out fires as may be applicable. Caution: Whenever fuel firing is curtailed, the fans should remain in operation to purge the unit of any unburned combustibles. Blow down drums and headers by opening drains and intermittent blowdown valves until the water level in the gauge glass reaches the low visibility point. Do not blow down drums using the continuous blowdown system. Continue blowdown, refill and re-fire steps until the water sample shows water to be clear of impurities. Cut the fires and cool the unit. Draining, Washing and Inspection With drum pressure at or below 5 PSIG, open all drum and header drains and vents to pressure drain the unit. This will increase velocities for flushing of non-soluble debris. Warning: Failure to open vents while draining the unit will result in a vacuum being developed within the unit. Attempting to open manways and handholes under vacuum may cause serious injury or death to personnel. Allow the unit to continue to cool before refilling to avoid thermal shock. Using fresh water refill and drain the boiler 3 to 4 times to remove any remaining boil out chemical residual on the heating surfaces. Open manways and with drains open wash down all accessible drum and tube internal surfaces with high pressure fresh water. Inspect all accessible surfaces for cleanliness. An additional boil out or chemical cleaning (acid cleaning) may be required predicated upon inspection results. Check tubes carefully as water and chemicals may have settled during the boil out and become stagnant. Check all pressure part valves for proper operation. Valves may have incurred material buildup or damage during the boil out process that could affect their operation. Replace the blowdown water with fresh water. Re-fire the unit to pressure and hold for 30 minutes to one hour after which shut down and repeat blowdown and re-fire sequence. Page 8 of 10

9 Post Boil Out Procedure Close up drum manways and header handholes. Re-fill boiler with fresh feedwater and prepare for remaining pre-operational cleaning processes. If the unit is not to be operated for an extended period, it is recommended that the surfaces be protected from corrosion. See Storage Steam Generators for procedures. Page 9 of 10

10 NOTES Indeck Keystone Energy, LLC Merwin Lane, Suite 100 Erie, PA For additional information contact: INDECK KEYSTONE ENERGY, LLC. Phone (814) Phone (800) Phone (800) Fax (814) Page 10 of 10