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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot Executive Summary The Program Manager for Assembled Chemical Weapons Assessment (PMACWA) of the Department of Defense (DoD) asked the National Research Council (NRC) to assess the engineering design studies (EDSs) developed by AEA Technologies, Eco Logic, and General Atomics for a chemical demilitarization facility to completely dispose of the assembled chemical weapons stored at the Blue Grass Army Depot in Richmond, Kentucky. The results of the committee’s scientific and technical assessment of the technology packages are presented in this report. This evaluation will support the selection by DoD of a technology for destruction of the assembled chemical weapons at Blue Grass. The record of decision (ROD), which finalizes the technology choice, is expected early in 2003. The committee evaluated the engineering design packages (EDPs) proposed by the technology providers, as well as results of experimental studies that were performed to support the designs of unit operations in the EDP. A significant part of this testing program involved expanding the technology base for the hydrolysis of energetic materials associated with assembled chemical weapons. (In its original report (NRC, 1999), the ACW I Committee had expressed concern about the hydrolysis process for destroying energetics.) The present study was conducted as the experimental tests were still in progress. Some supporting unit operations tests were not completed in time for the committee to incorporate the results into its evaluation. In those cases, the committee identified and discussed potential problems associated with the operations. Based on its expertise and aggressive data-gathering activities, the committee was able to conduct a comprehensive review of the test data that had been completed as well as the overall designs in the EDPs. BACKGROUND The U.S. Army is in the process of destroying the country’s stockpile of aging chemical weapons, stored at eight locations in the continental United States and on Johnston Atoll in the Pacific Ocean. The deadline for completing the destruction of these weapons, as specified by the Chemical Weapons Convention (CWC) international treaty, is April 29, 2007. Originally, the Army selected incineration as the preferred baseline destruction technology, and it currently operates two incineration facilities—one on Johnston Atoll and one at the Deseret Chemical Depot near Tooele, Utah. The Johnston Atoll Chemical Agent Disposal System (JACADS) completed destruction of the stockpile on Johnston Island in late 2000, and closure of the
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot facility is under way.1 Similar baseline incineration system facilities were planned for all of the remaining storage sites. However, incineration has met with public and political opposition. In response to this opposition, neutralization processes (based on the hydrolysis of chemical agent using either water or sodium hydroxide solution) were developed to destroy the chemical agents stored in bulk containers at Aberdeen, Maryland, and Newport, Indiana. For the five remaining sites in the continental United States, where munitions containing both chemical agent and energetic materials (i.e., assembled chemical weapons) are stored, incineration continued to be the planned approach for destruction. At three of these sites—Umatilla, Oregon; Pine Bluff, Arkansas; and Anniston, Alabama— baseline incineration systems are being constructed and will soon be ready for processing the chemical weapons. In late 1996, in the face of public opposition, Congress become involved and enacted Public Law 104-201. This law instructed DoD to “conduct an assessment of the chemical demilitarization program for destruction of assembled chemical munitions and of the alternative demilitarization technologies and processes (other than incineration) that could be used for the destruction of the lethal chemical agents that are associated with these munitions.” Another law, Public Law 104-208, required the Program Manager for Assembled Chemical Weapons Assessment (PMACWA) to “identify and demonstrate not less than two alternatives to the baseline incineration process for the demilitarization of assembled chemical munitions.” In addition, the law prohibited any obligation of funds for the construction of incineration facilities at the two remaining storage sites where no disposal facilities had yet been built—Lexington/Blue Grass, Kentucky, and Pueblo, Colorado. This prohibition was to remain in effect until the demonstrations were completed and Congress had assessed the results submitted to it by DoD. As a result of Public Laws 104-201 and 104-208, DoD created the Assembled Chemical Weapons Assessment (ACWA) program to select and evaluate technologies that would be appropriate for destroying the stockpiles at Pueblo Chemical Depot and Blue Grass Army Depot (NRC, 1999). Seven technology packages were considered in the initial round of the selection process, but one was rapidly rejected. Three of the six remaining underwent the first round of demonstration testing (Demo I). Two of the technologies tested in Demo I were selected as candidates for the destruction of chemical weapons at the Pueblo Chemical Depot: General Atomics’ Total Solution (GATS) process and Parsons/Honeywell’s Water Hydrolysis of Explosives and Agent Technology (WHEAT) process. The PMACWA subsequently initiated EDSs for the two technologies that had successfully completed Demo I. Congress also directed the PMACWA to demonstrate the remaining three technology packages that had not been selected for Demo I: AEA’s SILVER II™ process using mediated electrochemical oxidation; Eco Logic’s process using hydrolysis followed by transpiring-wall supercritical water oxidation and gas-phase chemical reduction (GPCR™); and Teledyne Commodore’s solvated electron technology (SET) using sodium in anhydrous ammonia followed by persulfate oxidation. After the Demo II results were in, PMACWA selected the AEA and the Eco Logic technology packages to proceed to the engineering design studies stage (EDS II). Accordingly, the AEA and the Eco Logic technology packages, along with GATS, have become candidates for the destruction of the chemical weapons at the Blue Grass Army Depot in Richmond, Kentucky.2 The purpose of the EDS phase is threefold: (1) to support the development of a request for proposal (RFP) for a full-scale facility; (2) to support the certification decision of the Under Secretary of Defense for Acquisition and Technology, as directed by Public Law 105-261; and (3) to support documentation required for the National Environmental Policy Act (NEPA) and the data required for a permit under the Resource Conservation and Recovery Act (RCRA). Each EDS comprises two parts: an EDP and engineering tests and studies to generate required data that were not obtained during the earlier demonstration test phase. 1 The stockpile on Johnston Island comprised 2,031 tons, or 6.4 percent, of the original 31,496 tons of chemical nerve and blister (mustard) agents in the U.S. stockpile. 2 The Parsons/Honeywell WHEAT process was deemed suitable for disposing of the mustard agent munitions stored at Pueblo Chemical Depot, but not for those at Blue Grass Army Depot. This is because the biotreatment component of the Parsons technology is not effective for the treatment of the hydrolysates from the organophosphorus nerve agents that are present at Blue Grass.
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot ROLE OF THE NATIONAL RESEARCH COUNCIL In 1997, in response to Public Law 104-201, PMACWA asked the National Research Council (NRC) to evaluate each of the seven technologies that had passed DoD’s initial screening. The Committee on Review and Evaluation of Alternative Technologies for Demilitarization of Assembled Chemical Weapons (ACW I Committee) did this and published its report in August 1999 (NRC, 1999). A supplemental review, requested by PMACWA to evaluate the tests for the three technologies selected for Demo I, was published in February 2000 (NRC, 2000a). Two of the technologies, General Atomics and Parsons/Honeywell, were judged ready to proceed to an engineering design phase. After it had completed the supplemental report, the ACW I Committee was dissolved. Subsequently, under the continuing mandate from Congress, the PMACWA requested that the NRC form a second committee (the ACW II Committee) to evaluate the engineering design packages and related tests for alternative technology facilities at Pueblo and Blue Grass and to examine and evaluate the Demo II tests of the three additional technologies that had not been tested in Demo I. STATEMENT OF TASK The present report is the committee’s response to the third and final task in its overall statement of task. The report will be produced in time to contribute to the record of decision (ROD) by the Office of the Secretary of Defense on the selection of a technology for the Blue Grass site.3 Task 3 For the third task, the NRC will assess the ACWA EDS phase in which General Atomics, Foster Wheeler/Eco Logic/Kvaerner, and AEA will conduct test programs to gather the information required for a final engineering design package representing a chemical demilitarization facility at the Lexington/Blue Grass, Kentucky stockpile site. It is expected that the testing will be completed at or around September 30, 2001. Based on receipt of the appropriate information, including: (a) the PMACWA-approved EDS Plans, (b) the EDS test reports produced by the technology providers, (c) PMACWA’s EDS testing database, and (d) the vendor-supplied engineering design package, the committee will: perform an in-depth review of the data, analyses, and results of the EDS tests assess process component designs, integration issues, and overarching technical issues pertaining to the proposed engineering design packages for a chemical demilitarization facility design for disposing of both nerve and mustard munitions produce a report for delivery to the PMACWA by April 5 provided the engineering design package is received by November 15, 2001. DESCRIPTION OF THE TECHNOLOGY PACKAGES The assembled chemical weapons stored at Blue Grass Army Depot contain either mustard or nerve agents; most of them are associated with energetic materials (Table ES-1). The technology packages consist of multiple unit operations that work in sequence or concurrently to carry out all aspects of the chemical weapons destruction. The EDP prepared for each technology is designed to be a total solution—that is, it is to treat all of the materials associated with disposal of assembled chemical weapons, energetic materials, metal parts (including munitions bodies), dunnage (e.g., wooden pallets and packing boxes used to store munitions), and nonprocess wastes (e.g., plastic demilitarization protective ensemble (DPE) suits; the carbon from DPE suit filters and from plant heating, ventilating, and air-conditioning (HVAC) filters; and miscellaneous plant wastes). Each EDP includes engineering drawings and documentation, a preliminary hazards analysis, and life-cycle costs and schedules. Short descriptions of the three alternative technologies considered for implementation at Blue Grass Army Depot are given below. More detailed descriptions of the unit operations for each technology are given in Chapters 3, 4, and 5. AEA Technology Process Figure ES-1 is a block diagram of the AEA SILVER II™ technology process. The following major operations are included: The chemical agent, energetic materials, and metal parts are separated using a modified version of the Army’s baseline system disassembly process. Munitions are punched, drained of agent, then opened and emptied of energetics materials. Chemical agent is mixed with concentrated nitric acid and silver nitrate. Ag2+ generated by the electrochemical cells quickly oxidizes the agent, 3 During the course of the ACWA testing program, delays were experienced and receipt of the results slipped into the first quarter of 2002. The NRC contract was therefore modified and a new date (August 15, 2002) was established for completion of the report.
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot FIGURE ES-1 AEA SILVER II™ demilitarization process. SOURCE: AEA (2001a).
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot TABLE ES-1 Description of the Chemical Weapons in the Blue Grass Army Depot Stockpile Item Fill Quantity Agent per Munition (lb) Total Agent (tons) Energeticsa Energetics Weight per Munition (lb) Total Energetics Weight (tons) 155-mm projectile, M110 H 15,492 11.7 90.63 Tetrytol 0.41 2.9 8-inch projectile, M426 GB 3,977 14.4 28.83 None 115-mm rocket, M55 GB 51,716 10.7 276.68 Composition B/ M28 propellant 3.2 74.46 19.1 448.99 115-mm rocket warhead, M56 GB 24 10.7 0.13 Composition B 3.2 0.035 155-mm projectile, M121/A1 VX 12,816 6 38.45 None 115-mm rocket, M55 VX 17,733 10.1 88.67 Composition B/ M28 propellant/ 3.2 25.53 19.1 153.95 115-mm rocket warhead, M56 VX 6 10.1 0.03 Composition B 3.2 0.0086 aTetrytol contains 70 percent tetryl and 30 percent TNT. Composition B contains 60 percent RDX, 39 percent TNT, and 1 percent wax. SOURCE: Adapted from U.S. Army (1997b). forming carbon dioxide, nitrogen oxides, water, and carbon monoxide. Energetics are size-reduced and mixed with concentrated nitric acid and silver nitrate to form a slurry. The slurry is mixed with Ag2+ from the electrochemical cells to oxidize the energetic material, forming carbon dioxide, nitrogen oxides, water, inorganic salts, and carbon monoxide. Metal munition parts are washed with dilute nitric acid and sent to a metal parts treater along with undissolved fuzes. Any agent remaining on the metal parts and the fuzes is destroyed by thermal decomposition. The resultant metal parts are decontaminated to a 5X level. Dunnage and DPE suits are decontaminated to a 5X level in a continuous steam treater. Gaseous effluents from the electrochemical, dunnage, and metal parts treatment processes are treated in an emission control system that uses thermal decomposition followed by catalytic oxidation, subsequent scrubbing, and carbon filtering. All treated gaseous effluent is discharged through the HVAC carbon filters for the munitions demilitarization building. On the basis of earlier results from Demo II testing, PMACWA asked AEA to perform EDS testing and studies on the following: Continuous destruction of agent simulant—dimethyl methylphosphonate (DMMP)—in a 12-kW test unit. Continuous destruction of energetic material (M28 and Composition B) in a 12-kW test unit. Assessment of burster washout methods for projectile and rocket bursters. Assessment of safe energetic concentrations for slurries containing energetic materials from the Blue Grass stockpile. Propellant size reduction by grinding, followed by some type of high-shear process. Particle size reduction and slurry mixing tests (for propellant and burster energetics) to identify a suitable technology for these functions; high-shear vortex mixers were selected and used in agent and energetics destruction testing. Testing of hydrocyclones for control of particle size in the feed streams to both agent and energetics electrochemical cells. Silver chloride separation and economic recovery of silver for recycling back to the process. Nitric acid evaporation from liquors of the electrochemical polishing circuit. Characterization and identification of fluoride removal methods for use when processing nerve agent GB. Confirmation of corrosion performance of the materials selected for process piping, vessels, and other components; the selected materials were polytetrafluoroethylene (PTFE) and perfluoroalkoxy (PFA) linings.
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot FIGURE ES-2 Schematic flow diagram of the Eco Logic technology package. SOURCE: Eco Logic (2001a).
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot Eco Logic Technology Process Figure ES-2 is a block diagram of the Eco Logic technology process. The primary treatment destroys the agent and the energetic materials by hydrolysis with caustic or water. However, the hydrolysis products (hydrolysates) must be further treated prior to final disposal. For this secondary step, Eco Logic proposes to use a transpiring-wall supercritical water oxidation (SCWO) reactor design. The following major operations are included: The chemical agent, energetic materials, and metal parts are separated using a modified version of the Army’s baseline system disassembly process. Rockets are punched, drained of agent, and disassembled. Projectiles are disassembled first and then drained of agent. Chemical agent and energetic materials are decomposed in three separate hydrolysis systems. The hydrolysates are further treated in a transpiring-wall SCWO system in which organic compounds are destroyed. Metal parts and dunnage are decontaminated to a 5X level, and gaseous effluents from the hydrolysis processes are treated in the gas-phase chemical reduction (GPCR™) system. The earlier Demo II tests generally confirmed the performance and efficacy of the GPCR™ process for the waste streams tested. However, problems with the agent detection method hampered a full evaluation of the process, and some concerns were raised about the selection of materials of construction when processing agent. In addition, the impact of processing energetics within the thermal reduction batch processor (TRBP) was not understood, and an effective method for grinding M28 propellant was not clearly demonstrated. Accordingly, a test program was implemented to investigate the following areas: development of analytical methods specific to the GPCR™ process the ability of the TRBP to process residual energetics from the munitions disassembly process corrosion testing of metals as materials of construction testing of the suitability of various elastomers for use in seals testing of equipment for grinding M28 propellant long-term testing of the transpiring-wall SCWO system Tests of the first five areas were completed, and the results were taken into account in the drafting of this report. The long-term testing of the transpiring-wall SCWO system developed by Foster Wheeler was ongoing at Dugway Proving Ground (Utah), and this report incorporates only the early results from these tests. General Atomics Technology Process Figure ES-3 is a block diagram of the General Atomics Technology Solution (GATS). The primary treatment destroys the agent and the energetic materials by hydrolysis with caustic or water. The hydrolysis products (hydrolysates) require further treatment before final disposal. For this secondary step, General Atomics proposes to use a vertical cylindrical configuration SCWO reactor. The following major operations are included: A modified baseline disassembly process is used; however, cryofracture is used to open the projectile bodies to access the agent. The bodies are cooled to the temperature of liquid nitrogen and fractured. Then the metal parts are separated from the agent. The agent-contaminated metal parts and other munition components are treated in a rotary hydrolyzer that rinses the parts with caustic solution and hydrolyzes any remaining chemical agent. Energetic materials are treated in a second rotary hydrolyzer in which the energetics are destroyed. The chemical agents and partially hydrolyzed agent and energetics from the rotary hydrolyzers are further treated with caustic in batch reactors until all the agent and energetics are destroyed. The dunnage is shredded and slurried with energetics hydrolysate. All the resulting hydrolysates and the slurried dunnage are treated by SCWO to produce environmentally benign products. All the metal parts are treated in a heated discharge conveyor to achieve a 5X condition. System offgases are processed through carbon filters. The GATS process underwent testing and develop-
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot FIGURE ES-3 GATS Blue Grass block flow diagram. SOURCE: General Atomics (2001a).
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot ment for approximately 3 years, reaching completion in January 2002. The unit operations tested were the dunnage shredder hydrolysis system (DSHS), the energetics rotary hydrolyzer (ERH), and the SCWO reactor. For this report, the committee concentrated on evaluating the following critical components of the GATS process design that had been identified as potential concerns in earlier NRC reports: the long-term reliability of the SCWO system for processing secondary waste feeds from the disposal processing of Blue Grass stockpile agents and munitions the advantages and disadvantages of cryofracture over the baseline technology as a means of accessing the agent in the munitions the ability of the projectile rotary hydrolyzer (PRH) and the ERH to process their respective feed materials in a reasonable time and with acceptable safety and reliability Methodology The committee formed working groups to perform in-depth evaluations of each technology package. As part of their efforts, the groups visited the EDS test sites at Aberdeen Proving Ground, Maryland; Dugway Proving Ground, Utah; and Deseret Chemical Depot, Utah. Committee members held review meetings and also attended PMACWA status-review meetings, which were held periodically. The technology providers and PMACWA staff provided draft copies of reports as they were generated. The final EDPs were released in December 2001. Results of most EDS tests and studies were also provided either before or during December 2001. Data gathering concluded on February 1, 2002; however, the committee continued to monitor final reports and updates on testing as it prepared this report. In evaluating the general efficacy of the design plans for a chemical demilitarization facility suited to the stockpile at the Blue Grass Army Depot and the readiness of each technology to go forward to the next level, pilot plant testing, the committee relied on its knowledge of the proposed systems, available test results, aggressive data-collection activities, and a thorough review of the engineering design plans and the past experience of the committee members. GENERAL FINDINGS General findings on the EDS phase of the ACWA program for the hydrolysis of energetic materials and the three technology packages evaluated in this report appear below. The general findings must be considered in light of the fact that a few of the ACWA EDS tests were not completed in time for the committee to obtain final test results and still meet publication deadlines, and that some process steps remain to be demonstrated on a pilot scale. Also, following its statement of task, the committee limited its evaluations to separate assessments of the total solutions proposed by AEA, Eco Logic, and General Atomics for destroying the assembled chemical weapons at Blue Grass Army Depot. That is, the committee has neither compared the proposed alternatives with one another nor compared them with the Army’s baseline incineration system. Specific findings and recommendations for each technology package, and for the PMACWA-sponsored investigations on hydrolysis of energetic materials, appear at the end of the related chapter. The energetics hydrolysis test program has been completed, and the results can be used to meet the engineering requirements for construction of a disposal facility at Blue Grass Army Depot. Issues concerning hydrolysis of neat tetryl, optimum granulation sizes, more complete characterization of hydrolysis products from aromatic nitro compounds, and optimum process control strategies for full-scale operations were among the issues investigated. General Finding 1. The reverse assembly of munitions, followed by water or caustic hydrolysis of nerve or mustard agents and associated energetic materials, is a mature, safe, and effective method for initial treatment of the chemical weapons stored at Blue Grass Army Depot. It is ready for immediate implementation for the neutralization of energetics and agents. However, the resulting hazardous streams must be treated further before they are released to the environment. This finding is based on the test results presented earlier in this report for the EDS hydrolysis of energetic materials and on the effectiveness of the modified baseline reverse assembly and agent hydrolysis processes discussed in this and previous NRC reports (NRC, 1999, 2001a). Because hydrolysis destroys agents and active energetics, the resulting hydrolysates
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot pose a lesser hazard than the assembled chemical weapons.4 This finding is independent of any subsequent secondary treatment steps that will be necessary to render the hydrolysates environmentally acceptable. That is, agent and energetics could be hydrolyzed even before the secondary treatment process is selected. However, further treatment is necessary to reduce hazardous waste concentrations to a level sufficiently low to allow for final disposal. Additional treatments will also be required for dunnage and the metals parts generated in the reverse disassembly process. General Finding (Blue Grass) 2. Several of the unit operations of the technology packages have process streams that are not unique to the chemical weapons stockpile. These streams, which include dunnage, brines from water recovery, and hydrolysates, could potentially be treated at existing off-site treatment, storage, and disposal facilities. Off-site treatment of these wastes would simplify the overall technology and facilitate process integration by eliminating the need for further development of individual process steps in the secondary treatment processes and their integration into a whole system. It might also simplify design requirements to meet safety concerns. All of the process streams that could be treated off-site have compositions similar to waste streams routinely treated by commercial industrial waste treatment facilities. Thus, they could be transported by standard commercial conveyance to commercial facilities that are appropriately permitted to receive the waste. General Finding (Blue Grass) 3. Based on the results of the PMACWA-sponsored test program on the hydrolysis of energetic materials, the committee believes that hydrolysis can be used safely, effectively, and on the scale necessary for the destruction of the energetic materials contained in assembled chemical weapons at Blue Grass, provided that lead-containing propellants are not processed with tetrytol until the possibility of lead picrate formation can be eliminated. The test plan that was executed at Holston Army Ammunition Plant (HAAP) demonstrated that the hydrolysis process for the energetic materials of interest successfully destroyed more than 99.7 percent of the energetics treated. Over 9,500 pounds of energetic materials were destroyed while encountering only the types of problems normally expected during the implementation of a new facility and process. The suite of tests performed at Los Alamos National Laboratory (LANL) and at HAAP covered a range of reaction temperatures and caustic concentrations. Under all these conditions, the destruction of energetics was carried out safely and effectively. Effective destruction of energetic materials during the test program is interpreted by the committee to mean that the products resulting from destruction no longer pose an explosion or detonation hazard. The committee notes, however, that the hydrolysate produced and the gaseous decomposition products are not benign. Gases such as ammonia and oxides of nitrogen are evolved, and cyanide or other toxic substances may be present in the hydrolysate. However, a variety of conventional methods for treating the offgases are available. The fate of lead during energetics hydrolysis in the presence of picrate is not understood. Until more information becomes available on the speciation of lead and the solubility of lead picrate under the conditions of hydrolysis, the possibility of solid lead picrate formation cannot be dismissed. As a precautionary measure, lead-based propellants should be processed separately from tetryl and tetrytol, eliminating the possibility of lead picrate formation. General Finding (Blue Grass) 4. Based on the results of EDS testing and the engineering design package, the committee believes that the AEA SILVER II™ total solution technology package could eventually destroy the assembled chemical weapons stored at the Blue Grass Army Depot. However, the immaturity of a significant number of processes in this electrochemical destruction technology could threaten PMACWA’s achievement of its objectives for weapons destruction. Considerable additional development and demonstration must be completed before this technology can proceed to a full-scale facility. There is also concern that the ever-increasing complexity and frequent configuration changes that have occurred in the AEA technology package to date are indicative of the immaturity of 4 All tests of agent destruction were performed with field-grade chemical agents produced at approximately the same time as the agents loaded into the chemical weapons. Thus, any complications arising from stabilizers, other additives, or degradation products were accounted for during testing.
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot the process. The approach employed by AEA has been to solve problems as they arise by incorporating additional steps that are modifications of previously demonstrated technologies. The technology provider infers the success of these new steps based on previous demonstrations in other applications but has not generated the data to show that the modifications will result in a safe, effective, and reliable integrated system for assembled chemical weapons destruction. The AEA SILVER II™ technology process does accomplish the following: It destroys chemical agent to a 99.9999 percent DRE and energetic materials to a 99.999 DRE by mediated electrochemical oxidation, provided that the following safeguards are observed: hydrocyclones are used on all slurry feed streams, high-shear vortex mixers are used, piping design minimizes dead legs, and all system equipment and piping use trace heating to prevent precipitation of energetic intermediates, and a second set of electrochemical cells is used to polish the anolyte to the required destruction level. It produces acceptable slurry compositions for processing burster energetics and rocket propellants. It safely treats process offgases using a combination of thermal treatment, catalytic oxidation, activated carbon filters, and treatment of the munitions demilitarization building (MDB) HVAC system ventilation air through activated carbon filter media prior to release. However, the committee notes that the effectiveness of some process steps has not been demonstrated: Removal of energetics from rockets using the new tube-cutting technology in a modified baseline RDM and achievement of agent-free energetics for processing by SILVER II™ electrochemical cells in a Category C area. Integrated operation of the primary and polishing anolyte circuits with a common catholyte circuit. Effective control of the flow of slurry mixture to a large number of parallel flow paths. (Currently, flow control has been demonstrated on only three parallel paths, whereas the full-scale application would have up to 432 parallel flow paths in the catholyte feed circuit.) Reliable operation of the electrochemical cell membrane, particularly for agent-containing slurries. (Currently, cell pressures and chemistry must be carefully controlled, and it is unclear if the membranes will work well in prolonged exposure to organophosphate-containing slurries.) Demonstration of a method to control the movement of fluorine and assure that all elements of the system exposed to fluorine-containing liquids and vapor streams can operate without excessive corrosion and maintenance. Decontamination of metal parts and fuzes to a 5X condition in the metal parts treater (MPT). Decontamination of dunnage and DPE suits to a 5X condition in the proposed, but as yet untested, enclosed-auger version of the dunnage treatment system (DTS) and successful management of dioxins and furans in the offgas from this process. General Finding (Blue Grass) 5. Stable operation of the ELI Eco Logic/Foster Wheeler SCWO system at the design conditions has not yet been demonstrated. The SCWO system for treatment of hydrolysates in EDS II testing exhibited frequent spiking in hydrocarbon and carbon monoxide concentrations in the offgas. This issue must be resolved before implementing the Eco Logic process at Blue Grass. If it is resolved, the committee believes that the Eco Logic package could provide an effective and safe means for destroying the assembled chemical weapons. However, the following design features still require validation: Design of the overhead conveyor system for the caustic bath should be tested to demonstrate satisfactory reliability. Removal of aluminum from the feed to the SCWO reactor. At this time, Eco Logic has not proposed an aluminum removal technology. Smoke abatement from the thermal reduction batch processor (TRBP) smoking rooms and the measurement and management of carbon monoxide and other products of incomplete combustion generated in these rooms. (These processes were not adequately addressed in the EDP.)
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot The Eco Logic technology does accomplish the following: It disassembles munitions by a modified baseline reverse-assembly technology. It destroys chemical agent to a 99.9999 percent destruction and removal efficiency (DRE) and energetic materials to a 99.999 DRE. It effectively treats solid and gaseous residues in a gas-phase chemical reduction (GPCR™) system and decontaminates solids to a 5X condition. It destroys by SCWO the hydrolysates and slurries that result from upstream processing. It adequately treats the low volumes of offgases produced in the process, including those from the SCWO reactors, through catalytic oxidation and activated carbon adsorption systems. The committee also points out the following: Eco Logic’s munitions reverse-assembly process starts with the baseline system technology, but modifications have been made. The rocket dismantling machine (RDM) operation is complex and differs in several aspects from the baseline operation. Further development of this process is needed. A testing program, described in Chapter 4, showed that the M28 propellant grinding could be done safely. However, additional testing with a larger, modified grinder is required to demonstrate any design modifications and to determine grinder and motor sizes for the full-scale plant. The Demo II tests generally confirmed the performance and efficacy of the GPCR™ process for the treatment of the waste streams from the process. However, problems with the agent detection method hampered a full evaluation of the process, and some concerns were raised about the selection of materials of construction for the processing agent. EDS testing has provided additional design data, but the results have not yet been used in operating systems. General Finding (Blue Grass) 6. Based on the results of the EDS testing and the EDP, the committee believes that the General Atomics technology package is an effective and safe method for the destruction of assembled chemical weapons at the Blue Grass Army Depot. The GATS SCWO system appears to have reached a level of maturity where construction and testing of a full-scale reactor to treat agent hydrolysate is the next logical step. Tests of the SCWO system have shown that the SCWO reactor requires frequent scheduled maintenance; however, the level of maintenance estimated by General Atomics for the Blue Grass application is manageable by well-trained operators and maintenance personnel. The committee still is concerned about possible problems associated with the extent of scale-up that will be needed for the SCWO reactor. Another concern is the proposed operation of the full-scale ERH and PRH in a continuous rather than batch mode and the maintenance difficulties that would result. The General Atomics technology does accomplish the following: It disassembles munitions by a modified baseline disassembly that removes the agent from the projectile bodies by cryofracture. It destroys chemical agents to a 99.9999 percent DRE by hydrolysis. It destroys fuzes by processing first in the ERH and then in the HDC. It destroys energetic materials by hydrolysis. It provides effective 5X-level decontamination for munition bodies using an electrically heated HDC. It destroys by SCWO the hydrolysates and slurries that result from this processing. It adequately treats the offgases produced in the process, including those from the SCWO reactors, through a CATOX unit and activated carbon adsorption systems. It is expected that weapons processing at Blue Grass will require no SCWO liner changes for the SCWO reactors treating energetics hydrolysates and dunnage slurried in energetics hydrolysates. For each of the two operating reactors used to treat agent hydrolysates, the technology provider has scheduled six liner changes that are estimated to be necessary for treatment of GB hydrolysate (i.e., 12 liner changes total for the GB campaign) over the 16-month operating life of the plant. During periods of steady operation with GB hydrolysate, based on six liner changes
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Analysis of Engineering Design Studies for Demilitarization of Assembled Chemical Weapons at Blue Grass Army Depot per reactor, each liner will be replaced after 110 hours of operation. It appears likely that liner change-out procedures in the full-scale system will encounter more problems than were encountered in the smaller test reactors used to date. Although no evidence was found of material hanging up in the ERH during the batch testing conducted to date, this is, in the committee’s opinion, a distinct possibility during the longer operating runs of a full-scale system in a continuous mode. The ERH is 50 feet long and the PRH is 40 feet long in the Blue Grass design. Should some form of blockage or other problem occur inside cylinders of this length, maintenance would be extremely difficult, especially considering that energetics and/or agent might be present. The tests demonstrated that the ERH and PRH appear to work well in a batch mode. Replacing the continuous-flow hydrolyzers proposed for Blue Grass with larger versions of the batch hydrolyzers used during the Demo I and EDS testing would appear to eliminate this risk and simplify system operation. General Finding (Blue Grass) 7. As the ACW I Committee observed, the unit operations in any of the three technology packages have never been operated as total integrated processes (NRC, 1999). As a consequence, a prolonged period of systemization will be necessary to resolve integration issues for the selected technology as they arise, even for apparently straightforward unit operations.
Representative terms from entire chapter: