5
Applicability of PCAPP Munitions Treatment Unit at BGCAPP

MUNITIONS TREATMENT UNIT DESIGN AND OPERATION AT PCAPP

The Pueblo Chemical Agent Destruction Pilot Plant (PCAPP) in Colorado will decontaminate metal parts from projectiles and mortars using two parallel munitions treatment units (MTUs). The MTUs have a footprint of approximately 90 ft long (with 20 ft of this total located in the munitions washout system [MWS] room, and 70 ft located in the MTU room) by 8 ft wide and an overall height of 12 ft. Off-gas from the MTU is discharged to an off-gas treatment system (OTS) using a bulk oxidizer (BOX) unit and cyclone for each MTU. The cyclones discharge to a common venturi scrubber system. The PCAPP OTS is similar in design and operation to the off-gas treatment system for the metal parts treater at the Blue Grass Chemical Agent Destruction Pilot Plant (BGCAPP).

The MTU is a continuous-belt muffle furnace with material-handling equipment at the feed and discharge ends. As shown in Figure 5-1, the MTU is an adaptation of a metal annealing furnace. Modifications include new feed and exit sections and a muffle large enough in cross section (10 in. high by 30 in. wide) to accommodate 155-mm projectile bodies riding on the metal conveyor. The muffle section is also long enough to ensure that all parts of the munitions reach 1000°F for at least 15 minutes at the operating speed of the metal conveyor.

Electrical resistance heaters externally heat the muffle walls, which in turn radiate heat to the munitions parts. The MTU OTS draws air into both the muffle feed section and exit section at a velocity sufficient to ensure the flow of any hazardous gases or particulates to the off-gas exit from the MTU muffle. The 20-ft-long feed section is located in the Level A area. The muffle, discharge, and cooling sections are located in the MTU Level C area and are approximately 70 ft long. Hot munitions bodies flowing from the MTU muffle section are cooled by air flowing into the MTU cooling section. The cooled munitions are discharged through a rotary valve onto an inclined conveyor in the Level C area into a bin located in a Level D area. From there, the munitions are shipped to a disposal facility. A paint-residue removal system is being incorporated on the MTU discharge.

Materials fed to the MTU consist of munitions bodies and mortar base plates. Located at the feed end of each MTU is a pneumatically operated tilt frame device equipped with a V-block support for the munitions and a weigh scale. This device, called the discharged munitions weigh station, weighs munitions bodies that have been processed through the MWS cavity access machine. The measured weight is used as the criterion to ensure that a full, unbreached munition is not fed into the MTU.

The MTU conveyor belt is a continuous link-and-pin design with scallops on the top side of each link that form a cradle for the munitions. The belt moves at a constant speed (nominally 4 in. per minute), presenting an open cradle to the MWS robot at regular intervals of time. The 155-mm and 105-mm munitions are deposited on a short ramp by the MWS robot and roll gently onto the furnace belt, cradling into the first available position. The 155-mm munitions are spaced on 7.5-in. center lines; the 105-mm munitions are spaced on 5-in. center lines. To balance mechanical stresses, the orientation of the 155-mm munitions are alternated between heavy-end left and heavy-end right; out-of-balance sequence munitions are limited to 10 or fewer in any running group of 40.

Mortar bodies are also deposited onto a ramp designed only for mortars that permits the accumulation of mortar bodies. Mortar bodies accumulate on the ramp while the MTU belt conveyor continues to move forward, providing empty space on the belt for the loading of base plates. After loading and accumulating four mortar bodies on the ramp, the MWS robot delivers a load of 25 base plates to the MTU conveyor belt. Base plates are deposited into a chute just forward of the mortar body loading ramp. After the base plates are deposited, the gate at the bottom of the ramp retracts, and mortar bodies are permitted to roll down



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5 applicability of PcaPP munitions Treatment Unit at BGcaPP mUNiTioNs TreaTmeNT UNiT desiGN aNd valve onto an inclined conveyor in the Level C area into a oPeraTioN aT PcaPP bin located in a Level D area. From there, the munitions are shipped to a disposal facility. A paint-residue removal system is being incorporated on the MTU discharge. The Pueblo Chemical Agent Destruction Pilot Plant Materials fed to the MTU consist of munitions bod- (PCAPP) in Colorado will decontaminate metal parts ies and mortar base plates. Located at the feed end of each from projectiles and mortars using two parallel munitions MTU is a pneumatically operated tilt frame device equipped treatment units (MTUs). The MTUs have a footprint of ap- with a V-block support for the munitions and a weigh scale. proximately 90 ft long (with 20 ft of this total located in the This device, called the discharged munitions weigh station, munitions washout system [MWS] room, and 70 ft located in weighs munitions bodies that have been processed through the MTU room) by 8 ft wide and an overall height of 12 ft. the MWS cavity access machine. The measured weight is Off-gas from the MTU is discharged to an off-gas treatment used as the criterion to ensure that a full, unbreached muni- system (OTS) using a bulk oxidizer (BOX) unit and cyclone tion is not fed into the MTU. for each MTU. The cyclones discharge to a common venturi The MTU conveyor belt is a continuous link-and-pin scrubber system. The PCAPP OTS is similar in design and design with scallops on the top side of each link that form a operation to the off-gas treatment system for the metal parts cradle for the munitions. The belt moves at a constant speed treater at the Blue Grass Chemical Agent Destruction Pilot (nominally 4 in. per minute), presenting an open cradle to Plant (BGCAPP). the MWS robot at regular intervals of time. The 155-mm The MTU is a continuous-belt muffle furnace with and 105-mm munitions are deposited on a short ramp by the material-handling equipment at the feed and discharge ends. MWS robot and roll gently onto the furnace belt, cradling As shown in Figure 5-1, the MTU is an adaptation of a metal into the first available position. The 155-mm munitions are annealing furnace. Modifications include new feed and exit spaced on 7.5-in. center lines; the 105-mm munitions are sections and a muffle large enough in cross section (10 in. spaced on 5-in. center lines. To balance mechanical stresses, high by 30 in. wide) to accommodate 155-mm projectile the orientation of the 155-mm munitions are alternated be- bodies riding on the metal conveyor. The muffle section is tween heavy-end left and heavy-end right; out-of-balance also long enough to ensure that all parts of the munitions sequence munitions are limited to 10 or fewer in any running reach 1000oF for at least 15 minutes at the operating speed group of 40. of the metal conveyor. Mortar bodies are also deposited onto a ramp designed Electrical resistance heaters externally heat the muffle only for mortars that permits the accumulation of mortar walls, which in turn radiate heat to the munitions parts. The bodies. Mortar bodies accumulate on the ramp while the MTU OTS draws air into both the muffle feed section and MTU belt conveyor continues to move forward, provid- exit section at a velocity sufficient to ensure the flow of any ing empty space on the belt for the loading of base plates. hazardous gases or particulates to the off-gas exit from the After loading and accumulating four mortar bodies on the MTU muffle. The 20-ft-long feed section is located in the ramp, the MWS robot delivers a load of 25 base plates to Level A area. The muffle, discharge, and cooling sections are the MTU conveyor belt. Base plates are deposited into a located in the MTU Level C area and are approximately 70 chute just forward of the mortar body loading ramp. After ft long. Hot munitions bodies flowing from the MTU muffle the base plates are deposited, the gate at the bottom of the section are cooled by air flowing into the MTU cooling sec- ramp retracts, and mortar bodies are permitted to roll down tion. The cooled munitions are discharged through a rotary 

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 aPPliCabiliTY OF PCaPP MuNiTiONS TReaTMeNT uNiT aT bgCaPP TesTiNG oF The mUNiTioNs TreaTmeNT UNiT For onto the conveyor belt behind the base plates. The loading PcaPP ramp empties as 16 more mortar bodies are delivered for the next sequence. Mortars are spaced on 5.0-in. center lines on Testing of the MTU took place at Abbott Furnace the conveyor belt. Company’s facility in St. Marys, Pennsylvania. The testing The heated portion of the MTU furnace is divided protocol was designed to verify the ability of the MTU to into six control zones. The temperature of the munitions process at the specified rates, heat all parts of each muni- is ramped up at a controlled rate in the first four zones and tion to at least 1000°F, and maintain that temperature for a allowed to remain at temperature in the last two zones. minimum of 15 continuous minutes. Additionally, the test- The zone length is determined by the kinetics of heating ing was to validate the structural integrity of the MTU, and the munitions and the desired soaking time at temperature. the ability of the MTU to control air flows and to control Munitions leaving the heated portion of the MTU enter a particulate matter generated by the thermal decontamina- water-jacketed cooling chamber zone designed to cool the tion process. munitions and the belt conveyor to approximately 650oF. The MTU performed to specification, demonstrating Experiments with simulated equipment test hardware muni- the ability to transfer all munitions types mechanically at tions have confirmed this temperature. the design rate, to heat all munitions types according to At the exit end of the cooling chamber, which is also the required thermal profile, and to manage the air flows as the exit of the MTU, is a rotary valve used to remove treated specified. Generated particulate matter showed no propen- metal parts. Munitions exiting the rotary valve are deposited sity to impair function. Design changes are planned in order onto a discharge conveyor and then leave the discharge con- to control particulate matter dusting at the discharge to the veyor by way of a discharge chute that penetrates the agent rotary valves. Operating procedures and control settings are processing building wall. The discharge chutes dump the being modified as well. metal parts into a container. After discharging metal parts to the rotary valves, the MTU conveyor belt returns to the comParisoN oF The meTal ParTs TreaTer aNd loading area, traveling underneath the MTU muffle. This mUNiTioNs TreaTmeNT UNiT For BGcaPP lower return tunnel includes the belt drive components and water seals that prevent the belt return tunnel from becom- The committee reviewed the applicability of the MTU ing contaminated by liquids and gases originating within the as an alternate method of decontaminating munitions bodies MWS room. and secondary waste at BGCAPP. As noted above, the MTU Off-gas from the MTU is discharged to the OTS through is currently planned for installation at PCAPP for thermal a vent located at the first heating zone of the MTU. The decontamination of 155-mm and 105-mm projectiles and vent is equipped with a filter to capture large particles from of 4.2-in. mortars that have been drained of mustard agent treated munitions (oxidized paint and so on) before the off- and passed through a high-pressure wash. In Table 5-1 the gas flows into a flameless thermal oxidizer designated as the committee compares various operating requirements and bulk oxidizer. The filter is rated for 1200°F, and differential features of the metal parts treater (MPT) and the MTU and pressure is measured across the filter to provide an indication identifies changes that would be required for the MTU to be of the need to clean the filter. Filter cleaning is accomplished used at BGCAPP. by using compressed air to blow particulates from the filter back into the MTU after the system is isolated by closing a Finding. The MTU could be used at BGCAPP for all projec- damper on the MTU vent line. tile bodies. Dimensional modifications of the PCAPP MTU Secondary and closure waste is not processed in the would be required to process 8-in. projectile bodies. MTU. Some of this material is combustible and would burn in the MTU muffle, since the muffle has air flowing through it Finding. The MTU is not designed for processing secondary to the MTU off-gas treatment system. These waste materials or closure waste. If used, it would also require the installa- will be processed in the PCAPP supplemental decontamina- tion of supplemental decontamination and autoclave units tion unit (SDU) or in one of two autoclaves. The SDU oper- at BGCAPP to treat solid waste, including squibs and fuzes ates at temperatures up to 400˚F. These temperatures will from the energetics batch hydrolyzers and secondary and cause thermal decomposition or pyrolysis of agent to levels closure waste. meeting guidance requirements of the State of Colorado for shipment to a commercial hazardous waste treatment storage Finding. Supplemental decontamination units and auto- and disposal facility. The SDU and autoclaves are designed to claves, if used at BGCAPP, would require space in the Level thermally destroy mustard agent contained in closed spaces B area of the munitions demilitarization building. in various waste items such as valves and pumps. They also Finding. A change from the MPT to the MTU will require will decontaminate demilitarization protective ensemble modifications to the environmental permits. The schedule suits, other plastics, contaminated wiring and hoses, other impacts for such a change have been estimated at delays of 7 operating and maintenance waste, and closure waste.

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 Exit chute Wall transition with with airseal flaps mounting plate sealed to the wall on the MTU Exit conveyor Oven muffle Curtain box “C” room side with flighted belt Water-cooled access port Chute Heated box chamber provided Oven muffle Controlled Vent to OTS by others Rotary drum Entrance muffle air inlet Transition area discharge and seal with curtain box Roll-off bin Water seal tank #2 with sample port provided Oven belt drive sprockets Shown for loading 105-mm by others and take-up area munitions,155-mm munitions, Robot Water seal tank #1 and mortar bodies; mortar base provided with sample port plates will have a different by others loading configuration figure 5-1 with new type Landscape view

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 aPPliCabiliTY OF PCaPP MuNiTiONS TReaTMeNT uNiT aT bgCaPP TABLE 5-1 Comparison of the Metal Parts Treater and the Munitions Treatment Unit Characteristic MPT at BGCAPP MTU at PCAPP Changes for MTU Use at BGCAPP Status of testing Prototype (~3/4 scale) Full-scale unit completed Full testing would be required, using the demonstrated on surrogate acceptance tests at the energetic dregs and agent or appropriate surrogate munitions and waste streams. manufacturer’s facility with material. Two full-size MPTs will surrogate munitions. Only small design changes from the PCAPP be built and tested at the MTU are required. Using the MTU would save manufacturer’s facility. extensive testing of the MPT with secondary waste. Treatment of secondary waste in the SDUa and autoclaves has already been performed at the other sites. Feed streams 4.2-inch mortars and base None 97,106 (HD) Applies only to PCAPP, no mortar rounds at plates BGCAPP. 105-mm projectiles None 383,418 (HD) Not applicable to BGCAPP. 155-mm projectiles 15,492 (H) 299,534 (HD) A new permit will be needed to use the MTU at 12,816 (VX) BGCAPP. 8-inch projectiles 3,977 (GB) None Muffle height must be increased for use at BGCAPP. The MTU currently has internal height of 9.75 in. and width of 30 in. M55 rockets; undissolved 51,716 (GB) None Squibs and fuzes must be thermally decomposed fragments, including 17,757 (VX) (must be popped). Some fragments are undissolved squibs and Method for treating squibs combustible and may require inert gas and special fuzes from hydrolysis of and fuzes in the MPT is to be baskets if treated in the MTU or, alternatively, rocket warhead and rocket tested. they may be treated in the SDU or autoclave if motor segments in EBHsb WCLc guidelines for off-site disposal are used. Secondary waste Thermal treatment in MPT Treatment in SDU or autoclaves. SDU and autoclave use based on approach used at ABCDF.d Use at BGCAPP may require special using special carrying trays. permitting and higher temperatures for GB- and VX-contaminated waste. Only limited testing on various waste types has been performed in the MPT. Closure waste Thermal treatment in MPT. Treatment in second SDU. See comments for secondary waste. Agents destroyed Mustard Yes Yes GB and VX Yes None SDU and autoclave would be required with the MTU for GB- and VX- contaminated waste streams. This method of decontamination may require higher treatment temperatures to achieve acceptable treatment times to meet WCL guidelines for off-site disposal. Number of units 2 MPTs with one for projectile 2 MTUs with only one ordinarily BGCAPP might require only 1 MTU because the processing and one for waste required to meet PCAPP number of projectiles is an order of magnitude streams and as a backup spare. processing rates. less than at PCAPP; MTU availability expected to be higher than that of the MPT. ~70 ft long × 40 ft wide × 20 ~100 ft long × 30 ft wide × 20 MDBe footprint MTU would require changes in BGCAPP MDB ft high ft high layout to accommodate longer processing length and SDU and autoclave units and to provide for Total direct footprint for 2 Total direct footprint for 2 MTUs collection bins for receiving treated metal parts MPTs plus 50 percent of MPT/ is 5,100 square feet plus 216 from MTU discharge chute. washout support room plus square feet for collection bin MPT cooling room is 4,640 enclosures. square feet. Post-treatment agent clearance In exit air lock before leaving In treated munition collection MTU use at BGCAPP would require permit level A area. bin in Level D area. change for use of current MTU discharge configuration. continues

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 ReView aNd aSSeSSMeNT OF deVelOPMeNTal iSSueS CONCeRNiNg The MeTal PaRTS TReaTeR deSigN TABLE 5-1 continued Characteristic MPT at BGCAPP MTU at PCAPP Changes for MTU Use at BGCAPP Atmosphere in unit Nitrogen in air locks and Air flowing from both ends of Change in Kentucky permit would be required for superheated steam in main muffle to off-gas duct exit from use of MTU and SDU or autoclave. chamber. muffle system. Off-gas treatment system Flame arrestor, cyclone, bulk Flame arrestor, filter media, bulk Same components, with different gas flow rates oxidizer, venturi scrubber, and oxidizer, venturi scrubber, and and sizes. reheater. reheater. Method of heating 2 induction coils at 450 kW Resistance heaters at 600 kW None each plus 75 kW resistance heating for steam superheater. Method of operation Batch Continuous Would have to change from a batch stream to a continuous stream. Char and tar buildup Expected, but the design Secondary waste not processed Secondary waste not processed in MTU. from secondary waste allows for addressing tar and in MTU. treatment char buildup. Method of control of Doors and seals on air locks Curtains on munitions cold feed Curtains on munitions cold feed end and cooling atmosphere in main attached to main chamber. end and cooling section exit of section exit of muffle. treatment unit muffle. Overall availability 83 percent estimated using 91 percent estimated for single Both estimates based on using both treatment (percent of time the spare MPT. MTU; no estimate given with units. system will be operating) spare MTU. Munitions throughput rates 4.2-inch mortars None for BGCAPP ~60/hr 105-mm projectiles None for BGCAPP ~60/hr 155-mm projectiles ~40/hr ~40/hr ~40/hr 8-inch projectiles ~15/hr None MTU should be capable of modification to achieve BGCAPP 8-inch projectile processing rates. aSDU,supplemental decontamination unit. bEBH,energetics batch hydrolyzer. cWCL, waste control limit. dABCDF, Aberdeen Chemical Agent Disposal Facility. eMDB, munitions demilitarization building. SOURCE: Adapted from BPBGT, 2007c. to 11 months for construction. Because stakeholder concerns proximately 360 of these items from five EBH waste batches are difficult to predict, these estimates could be optimistic, are combined and placed in a single waste incineration and actual schedule impacts could be greater. container for thermal treatment. The method of controlling the energetic releases in the MPT or MTU and SDU has not been identified. TreaTmeNT oF eNerGeTics BaTch hYdrolYZers The alternatives selected for treating secondary and aNd secoNdarY aNd closUre WasTe aT BGcaPP closure waste at PCAPP are an SDU and an autoclave. The The Bechtel Parsons Blue Grass Team (BPBGT) plans SDU is an industrial convection oven.1 The units planned for to use the MPT for the treatment of both munitions bodies PCAPP are 12 ft 3 in. wide by 6 ft 6 in. deep by 8 ft 8 in. high and energetics batch hydrolyzer (EBH) and secondary and in internal volume. The door opening is 40 in. by 80 in. The closure waste. If the MPT were to be replaced with an MTU, floor loading capacity is 4,000 pounds per bay. The units are EBH and secondary and closure waste would have to be designed to operate at temperatures up to 500oF at a slight treated by alternative methods because they would be subject to combustion and popping in the MTU. The BPBGT is still evaluating how to thermally treat 1Open discussion on the SDU/autoclave, between Craig Myler, Chief EBH waste streams, including squibs and fuzes. According Scientist, Pueblo Chemical Agent Destruction Pilot Plant, and the commit- tee, September 20, 2007. to the Technical Risk Reduction Program test report, ap-

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 aPPliCabiliTY OF PCaPP MuNiTiONS TReaTMeNT uNiT aT bgCaPP negative pressure relative to the surroundings. Operating need to be approved by the State of Kentucky. Maximum temperatures for materials contaminated with mustard will temperatures in the autoclave may be insufficient to handle be in the range of 275oF to 350oF. Total estimated cycle time VX contaminated wastes. from start up to cooldown is 19 to 22 hours, depending on Finding. The BGCAPP permit would require modification if the material and the degree of contamination. The autoclave is an industrial vacuum cycle unit, 26 in. the MTU/SDU/autoclave were to be used instead of the MPT wide by 78 in. deep by 62 in. high in internal volume. The because the process design would be totally different. door opening is 26 by 62 in. The floor loading capacity is Finding. If used at BGCAPP, the MTU, like the full-size approximately 300 pounds. The autoclave is designed to op- erate at up to 267oF at pressures of 2 to 32 pounds per square MPT, would first require acceptance testing at the manufac- inch gage (psig). Materials contaminated with mustard will turer’s facility. Both units would then undergo first-of-a-kind be heated with steam to a maximum temperature of 267oF testing during systemization. and then cooled by the application of a vacuum. Total cycle Finding. Although the footprints of both the MPT and the time is estimated between 7.5 to 8.5 hours. Thus, PCAPP is not planning to heat secondary and MTU are similar in area, the MTU will have a longer and closure wastes to 1000oF for 15 minutes, the traditional narrower footprint that will require modification of the floor method for certifying waste as agent-free and suitable for plan at BGCAPP. off-site disposal. Instead, PCAPP will take advantage of the Finding. The use of supplemental decontamination units approach based on waste control limits (WCLs) that went into effect in June 2004. There are several variations of the and autoclaves at BGCAPP will be required to treat second- WCL approach. The State of Colorado has approved a vapor ary and closure waste if the MTU is selected for processing screening level (VSL) for certifying waste treated in the SDU munitions bodies at BGCAPP. The supplemental decon- or autoclave as agent-free. A gas/vapor sample will be taken tamination unit and autoclave operating temperatures will at the end of each thermal cycle to determine if the cycle not be the same as at PCAPP because higher temperatures was sufficient to achieve the desired decontamination of less are required for GB and VX than for H or HD to achieve than 1 VSL. Monitoring will require at least two consecutive thermal decomposition rates suitable for anticipated waste readings below 1 VSL that are not rising. The monitoring production rates. MINICAMS® must pass a post-test agent challenge to ensure Finding. The use of waste control limit guidelines will be that the presence of interferents did not suppress the agent readings. The VSL has been set as 1 short-term exposure required for the disposal of waste exposed to H, HD, GB, and limit (0.00001 mg/m³), established by the Army in coordi- VX if supplemental decontamination units and an autoclave nation with the Centers for Disease Control and Prevention are used at BGCAPP. These guidelines for waste exposed to (NRC, 2007). these agents have already been implemented at other chemi- The SDU and autoclave planned for PCAPP should be cal demilitarization facilities. of sufficient size to handle the secondary and closure waste Finding. A method has not been developed for treating expected to be generated at BGCAPP. The SDU would have to be operated at higher temperature and possibly for longer squibs and fuzes from the energetics batch hydrolyzer waste times in treating waste contaminated with VX. Available data streams in either the MTU/supplemental decontamination indicate that the half-life for VX is 4 minutes at 482oF and 0.6 unit or the MPT. minute at 563oF. Assuming that the rate of destruction is first Finding. The off-gas treatment systems for BGCAPP and order with respect to time, the estimated times to achieve six nines (99.9999 percent) destruction and removal efficiency PCAPP are quite similar for the MPT and the MTU. The are 80 minutes and 11 minutes, respectively. An appropriate MTU does not require a particulate cyclone downstream of WCL and associated sampling and analysis method would the bulk oxidizer unit.