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Alternative Technologies for the Destruction of Chemical Agents and Munitions 4 Requirements and Considerations for Chemical Demilitarization Technologies As discussed in Chapter 2, the U.S. chemical weapons stockpile exists in several forms. Some chemical agent is stored as bulk liquid in ton containers. Much, however, comes in weapons that are ready for transport to the battlefield and can be fired after relatively simple arming procedures. For such weapons, the current destruction or demilitarization baseline program includes reverse assembly, in which chemical agent is first separated from weapons containers and any explosives or propellants. Technologies used for chemical agent destruction must entail a very low risk of agent release to the workplace and the environment. Because of the agents' extreme toxicity, the standards for their destruction (including the decontamination of weapons parts that have been in contact with agent) are much more demanding than the standards for the destruction of other chemicals. The serious consequences of any inadvertent release of agent near adjacent populations requires that the systems design for any disposal facility provide strict controls for the release of any substances to the environment. It may also be desirable to store waste streams for testing before releasing them to the environment. Stringent requirements are needed to protect worker safety and health. Finally, all effluents must also meet applicable regulatory requirements. This chapter describes the major requirements and considerations relating to chemical demilitarization: chemical composition of agents and their breakdown products; waste streams resulting from chemical weapons destruction; including that from the reverse assembly procedure used to avoid complications in destroying explosive weapon components; processing rates required for chemical demilitarization; performance standards for all effluent air, liquid, and solid streams: standards are discussed for single-step operations in which full destruction and decontamination are accomplished by a single process, and for multiple-step
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Alternative Technologies for the Destruction of Chemical Agents and Munitions operations that allow the transport of partially decontaminated wastes to other sites for full decontamination; general factors governing the probable applicability of any untested alternative technology to the destruction of waste streams and the decontamination of weapons and other metal parts; current monitoring capability for detecting residual chemical agent, including its methodology, accuracy, and time requirements; effluent retention time requirements and related process shutdown time requirements to certify the safety of effluents before their release to the environment; issues of development time and costs; and assessment criteria for alternative technologies. CHEMICAL COMPOSITION OF AGENTS AND THEIR BREAKDOWN PRODUCTS Chemical agents in the U.S. stockpile are composed of carbon (C), hydrogen (H), oxygen (O), fluorine (F), chlorine (Cl), phosphorus (P), and sulfur (S). All these elements will be present in the waste streams, in type and quantity corresponding to agent inputs, independent of the choice of destruction technology. Most of the technologies that might be used would ultimately yield fully oxidized products, as discussed below, with the heteroatoms (noncarbon atoms F, Cl, S, and P) in the form of stable salts. For some alternative technologies, the final waste stream would be identical to that of the current baseline incineration technology. A number of either low-or high-temperature oxidation processes could oxidize carbon atoms to carbon dioxide (CO2) gas; this CO2 could be incorporated in a salt such as calcium carbonate. Biological reactions could be used to incorporate the carbon in a form of sewage sludge or a thermal reaction could be used to form both CO2 and a tar or char suitable for disposal. In one special process (see Chapter 7), a reaction with sulfur vapor would form a carbon-sulfur equivalent of a solid char. The release of intermediate organic compounds to the liquid or gaseous waste streams at concentrations above those set by regulatory standards would be unacceptable. Ideally, all hydrogen would be fully oxidized to water. The water would be released along with the CO2 from the stack or it could be condensed, purified, and recycled. Solid organic compounds in any sewage sludge produced would also contain hydrogen. The amount of oxygen present in the chemical agent is less than that required to fully oxidize the carbon and hydrogen atoms. It is assumed to appear as CO2, water, a carbonate or in solid organic compounds in disposable sludge.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions The remaining elements of interest (fluorine, chlorine, phosphorus, and sulfur) will generally be converted to their acidic or oxidized forms, HF, HCl, P2O5, and SO3 (H2SO4 in the presence of water), and ultimately to their related salts. Soluble salts would need to be disposed of in a hazardous waste site to prevent their leaching into groundwater. It is preferable to form the relatively insoluble calcium salts, such as CaF2, CaSO4, and Ca3(PO4)2. Unfortunately, all the alkali chlorides (which would form from Cl) are quite water soluble. WASTE STREAMS IN CHEMICAL WEAPONS DESTRUCTION As discussed in Chapter 2, chemical agents are stored as liquid in large containers or contained in weapons ready to ship to the field. Field-ready weapons contain explosive charges (bursters) that on detonation disperse agent as fine droplets. Bursters are detonated by fuzes that can usually be separated from the weapons. Land mines have bursters; their fuzes are stored with but disassembled from the mines. There are 105-ram projectiles configured both with and without bursters, fuzes, and cartridge cases containing propellant. Most 155-ram and 8-inch projectiles contain bursters but are not fuzed. In addition to fuzes and bursters, M55 rockets contain both rocket propellant and its igniter. Because the presence of explosive components would greatly complicate the contained destruction of chemical agent, the baseline technology includes a reverse assembly procedure for these weapons before the agent contained is destroyed. Explosive components are completely removed from projectiles and land mines (except when mechanical resistance to removal may require special treatment). Liquid agent is then either drained or evacuated from the container, resulting in two process streams: (1) bulk liquid that is accumulated in a batch tank until enough is available for bulk liquid processing and (2) the drained but still contaminated projectile shells, mine casings, and ton containers, referred to as metal parts. Explosive components separated in reverse assembly, whether contaminated or not, must be destroyed in a system capable of withstanding their explosion. M55 rockets were not designed to be disassembled but are contained within fiberglass tubes that make reverse assembly essentially impossible. As a result, individual rockets are fed to a rocket shear machine, which punches several vertical holes through the rocket and its encasing tube, drains the liquid agent into a storage tank, and shears the rocket into small pieces. With the current baseline technology, which has been tested at the Johnston Atoll Chemical Agent Disposal System (JACADS), the rocket drain and shear actions occur within rooms designed to contain and isolate any explosions (Figure 4-1). The stored agent is processed in bulk, and a deactivation furnace
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Alternative Technologies for the Destruction of Chemical Agents and Munitions system is then used to simultaneously destroy residual agent, explosives, propellants and decontaminated residual weapons parts. Subsequently, a heated discharge conveyer ensures the time and temperature requirements for thermal decontamination of the rocket pieces by carrying burned materials on an electrically heated conveyor for at least 15 minutes. In addition to the above main component streams, additional solid wastes of the disposal process include wooden shipping and storage pallets, the protective clothing used by personnel, cleanup equipment, and other items potentially contaminated by chemical agent. These wastes are called dunnage and are combined for disposal with any compatible solid wastes from other processes in the system. The requirement to treat this waste stream is optional; experience at the baseline facility has shown that the contamination of these wastes is low and they can be chemically cleaned (e.g., with decontamination fluids) to a level that allows their transport and disposal in a hazardous waste landfill. Any alternative process that fails to destroy the chemical agent completely or that creates new wastes that cannot be discharged to the environment may create additional process stream requirements. An example of such new wastes might be the scrubbing solution used in decontaminating equipment (and related salts, if the solution is reduced to a solid waste stream); in the baseline technology, these wastes are fed to the liquid incinerator. Finally, all work spaces are normally ventilated with the air flow proceeding in the direction of increased probability of contamination, from the control room and analytical laboratories through the work areas. Each succeeding area is maintained at slightly lower pressure to ensure that this positive flow, and thus any leakage, occurs in the proper direction. In all, therefore, six main process streams must be treated: (1) bulk liquid agent; (2) solids contaminated with agent without explosives or propellants; (3) solids with explosives or propellants contaminated with agent; (4) solid dunnage, such as packing materials and used protective suits; (5) decontamination fluids; and (6) ventilation air. PROCESSING RATES The rate at which weapons and their resultant process streams must be destroyed is set by several factors. First, all weapons and agent at each site must be demilitarized by a target completion date. As noted in Chapter 1, this
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Alternative Technologies for the Destruction of Chemical Agents and Munitions FIGURE 4-1 JACADS demilitarization process. Source: PEIS (1988).
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Alternative Technologies for the Destruction of Chemical Agents and Munitions date was initially set by U.S. legislation and has been extended several times. To comply with international treaty, it was recently reset to December 31, 2004. Second, only part of the time from now through 2004 is available for operations. There are many other necessary steps: technology selection; environmental reviews; congressional authorization; possible research, development, and demonstration of any alternative technology; design, permitting, construction; and testing of facilities. In addition, these times could be prolonged if multiple-step destruction processes required the transport of partially decontaminated materials to one or more centralized full-decontamination facilities. One option discussed by the committee (see Chapters 1 and 8) might relieve the time pressure at some sites while allowing agent to be detoxified and weapons disassembled to meet treaty requirements. Final oxidation of all organic residues, destruction of energetics, and decontamination of metals could be deferred by local storage or transport of partially treated materials to other sites. The processing rate for agents and munitions will probably be set by the mechanical operations in the reverse assembly process. This process will set both a maximum rate, due to mechanical limitations, unless the reverse assembly process is increased by multiple lines, and a minimum rate for performing these operations with a reasonable degree of efficiency. Significant delays between reverse assembly and later decontamination and destruction steps would add to internal inventory storage requirements as well as increase the probability of accidents. The current program was designed so that the first disposal facilities would be constructed at sites with the largest chemical weapon storage inventories. The baseline technology would then be used at the sites with smaller inventories, resulting in shorter total operating periods. Processing rates for the largest continental site inventory at Tooele Army Depot (TEAD) are set to destroy the inventory in 4 to 5 years, with a specified flow rate of 1050 pounds of liquid agent per hour. This rate is about 50 percent greater than the collection rate from the simultaneous operation of two identical M55 reverse assembly lines, each having a nominal capacity of 35 rockets per hour (U.S. Army Corps of Engineers, 1987).1 The 155-mm projectile processing rate, at 500 projectiles per day, is only 130 pounds of agent per hour. For the smaller stockpile sites, a nominal capacity of 100 pounds per hour of agent destruction is assumed in subsequent discussion of waste gas storage technologies. 1 If two reverse assembly lines are used, each at a rate of 35 M55 rockets per hour, with 10.5 pounds of agent per rocket, the accumulation rate of drained agent will be 735 pounds per hour.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions PERFORMANCE STANDARDS Chemical agent destruction technologies must meet various performance standards, including those for worker protection, ambient air quality control, and liquid and solid waste control. These standards are generated by several different regulatory agencies, including the Environmental Protection Agency, National Institute for Occupational Safety and Health, and U.S. Department of the Army, and by such laws as the Occupational, Safety and Health Act, the Resource Conservation and Recovery Act, and the Toxic Substances Control Act. Special regulations are also imposed by the Army to meet the requirements necessitated by the especially toxic nature of the chemical agents. These special Army regulations are the main focus of the discussion below. Worker Standards Aside from protection against possible explosions and other industrial accidents, all handling processes are designed to preclude worker contact with chemical agent. This includes the requirement to use full-body, plastic protective suits, into which a worker is sealed (a Demilitarization Protective Ensemble, or DPE). The DPE includes a remote clean air supply for work in contaminated areas where the airborne exposure would likely exceed the maximum permissible level for workers (see Table 4-1). Air Quality Standards The Army has several air quality standards (permissible hazard concentrations) depending on the specific chemical agent and location. These and lethal dose estimates for agents are shown in Table 4-1. Liquid Wastes State and community standards for water effluents and drinking water should be satisfied. As a practical matter, it is normally better to recycle the most contaminated water internally in the plant processes.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions TABLE 4-1 Permissible Agent Hazard Concentrations in Air and Lethal Doses Permissible Hazard Levels in Air(mg/m3) Lethal Human Doses Agent Workersa Stack Emissionsb General Populationc Skin (LD50, mg/kg) Intravenous (LD50, mg/kg) Inhalation (LCt50, mg—min/m3) GA 0.0001 0.0003 0.000003 14-21 0.014 135-400 GB 0.0001 0.0003 0.000003 24 0.014 70—100 VX 0.00001 0.0003 0.000003 0.04 0.008 20-50 H/HD/HT 0.003 0.03 0.0001 100 — 10,000 L 0.003 0.03 0.003 — 100,000 a For 8-hour exposure. b Maximum concentration in exhaust stack. c For 72-hour exposure. Note: The Army standards shown in the first three columns set the minimum level of performance required for gas release by any alternative process and are applicable to all four process streams. LCt50 and LD50 represent dosage that result in 50 percent lethality. Source: U.S. Department of the Army (1974, 1975); PEIS (1988). Solid Wastes A major consideration at JACADS is the segregation of waste that may have been contaminated by agent from other hazardous and nonhazardous waste. Waste that is known never to have been contaminated is handled as simple hazardous or nonhazardous waste. The Army has three self-imposed categories of chemical agent contamination of solid wastes: Level 1X is contaminated material that has not yet been processed or that still has detectable agent according to air monitoring above the material. This material must be controlled according to Army regulations and procedures. Level 3X was established primarily for worker safety to indicate potentially contaminated material or previously contaminated material that has been decontaminated to show zero residual contamination by air monitoring above the material. Such material includes wood pallets that have
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Alternative Technologies for the Destruction of Chemical Agents and Munitions held rockets that leaked and metal parts that contacted agent but have been decontaminated and verified by a monitor not to have agent. Worker contact with 3X materials is allowed under normal working circumstances, but release of these materials to the public for uncontrolled access or use is not allowed. (Some 3X waste salts and 3X dunnage are currently transported to hazardous waste sites for controlled landfill, i.e., a disposal method that presumably precludes public access and makes 5X treatment unnecessary.) Level 5X is fully decontaminated material with no detectable residual contamination that has had heat treatment of at least 1000°F for at least 15 minutes. 5X material can be released to the public for uncontrolled access or use. The high-temperature treatment is required to destroy any residual agent that may be inaccessible to chemical treatment. To produce solid waste meeting the current 5X standard, any alternative technology would have to treat contaminated solids with 1000°F for 15 minutes. This requirement precludes several low-temperature alternative technologies. Consequently, the committee has assumed the acceptability of adding ''or equivalent'' to allow other treatment processes to be considered for meeting the 5X requirement. The equivalent could be, for example, treatment at a higher temperature for a shorter time. The "equivalent" capability would still have to be demonstrated, and the Army's self-imposed regulation would need to be changed to reflect the new conditions. For decontamination purposes, the Army is considering a new alternative 5X standard for the destroying GA and GB nerve agents associated with local accidents, the resulting contamination, and the reoccupation of related housing. This alternative would require that any residual material be subjected to appropriate tests (not yet defined) to show that the air over the sample has an agent concentration of less than 3 ng/m3 for 72 hours, that is, meets the air quality standard for the general population. However, the alternative standard would not apply to mustard agent (HD), because mustard is believed to be carcinogenic and no lower threshold (below which damage will not occur) has been established. The new standard is not intended to be applied to the primary operations at agent destruction facilities. GENERAL CONSIDERATIONS IN ASSESSING UNTESTED ALTERNATIVE TECHNOLOGIES Most potential alternative technologies have not been tested with the chemical warfare agents in the U.S. stockpile. It is therefore necessary to judge whether such technologies will likely meet the very stringent destruction requirements when tested. An initial judgment can be made about a technology's probable success in destroying bulk chemical agent by considering the technology's success in destroying similar bulk chemicals. A
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Alternative Technologies for the Destruction of Chemical Agents and Munitions further judgment must be made about the ability of any alternative technology to decontaminate metal parts, explosives, propellants, dunnage, and other components. (It may be possible to deal with dunnage by disposal in hazardous landfills.) Decontamination Standards The Army has developed data over a number of years in support of the current 3X and 5X criteria (see Appendix H). Thins work has included a variety of tests on the liquid forms of all agent types, at various temperatures and times, and with and without oxygen present. Tests have also addressed the decontamination of solids containing the different agents. Previous Army experience showed that past chemical treatment processes left residual agent contamination on metal parts that was detectable on subsequent thermal treatment.2 However, these activities have not included the use of somewhat more reactive chemicals, such as ammonia gas or corrosive adds, at elevated temperatures and for longer times. In principle, with further research and proper choice of reagents, it may be possible to chemically decontaminate metal parts. New ways to certify such decontamination would have to be developed. In conjunction with a development program to chemically destroy agent from ton containers, research to identify low-temperature chemical processes that would match the 5X thermal treatment decontamination would be useful. These results suggest that some consideration should be given to the fundamentals of the problem to indicate the likelihood that similar alternative technology could achieve the equivalent of full 5X decontamination. Current analytical techniques can measure 0.6 ng/m3. For GB, with a molecular weight of 140, this is equivalent to 2.6 × 1012 molecules/m3. The typical solids waste debris box being sampled holds about I to 2 m3 of solid wastes. Because GB has a molecular diameter of roughly 10 angstroms, the detectable number of molecules in such a debris box, if spread out into a monomolecular layer, would have a surface area of only a few square millimeters. GB readily wets metal surfaces, and thus only a few small cracks or crevices would be required to contain more than the allowable residue of GB. Further, removal of agent from crevices is likely to be much slower than from an exposed flat surface, because of the limited surface area at the opening of a crevice, the possible blocking of the opening by reaction by-products, and the reduced vapor pressure of the liquid in a crevice. The incomplete reaction observed with decontamination solution is probably due 2 U.S. Army Program Manager for Demilitarization, presentations to the committee at its March 9-10, 1992, meeting.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions to a diffusional limitation, a limitation that would also probably limit the use of microbial organisms or their related large molecule enzymes. The diffusion of heat in solids, liquids, and gases occurs at a much higher rate than molecular diffusion. Thus, the ability of heat to reach and destroy isolated pockets of agent makes heating the process of choice to date for decontaminating residual agent from the surface of solids. Chlorinated Dioxins In addition to providing for the complete destruction of the chemical agent, any alternative process must not inadvertently create other harmful waste products. Of special regulatory concern is the possible production of chlorinated dioxins by recombination of the components produced in the primary agent destruction process. Chlorinated dioxins can be formed in waste gas streams where the temperature is 180 to 400°C and where chlorine and reactive hydrocarbons are present. The reactions take place on the surface of inorganic particulate matter. Salts of iron, copper, and aluminum, as found in fly ash from coal combustion, catalyze this reaction. Subjecting chemical agents to high-temperature pyrolysis or oxygen-deficient combustion will also produce hydrocarbon fragments, which, if not destroyed in an afterburner before cooling to below 400°C, can lead to chlorinated dioxin formation if chlorine is present. The agents GB and VX contain no chlorine; however, HD can be a major source. Nonetheless, because the concentration of allowable chlorinated dioxins is extremely small, even small quantities of chlorine (such as may be present because salt in the air used in oxidation processes) may be sufficient to produce significant quantities of chlorinated dioxin if the proper conditions for the recombination reactions exist. Thus, all processes should be selected and designed to minimize the time spent in the critical 180 to 400°C temperature range and to have subsequent process steps for adequately removing any chlorinated dioxins that are formed. Although the 5X decontamination equilibrium conditions of 1000°F (538°C) for 15 minutes are somewhat above the recombination temperature range, they may allow some synthesis of chlorinated dioxins. More important is that the decontamination of metal parts is inherently a batch process with a substantial heat up time (minutes). Bemuse volatile organic compounds will be released during this heat up period, some chlorinated dioxins may be formed as the heat up progresses through the critical 180 to 400°C temperature range. Further, although subsequent afterburning of any off-gases may destroy these chlorinated dioxins, they might again be produced in the subsequent cooling of the gas if adequate hydrocarbon and catalyst surface still remain
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Alternative Technologies for the Destruction of Chemical Agents and Munitions and if the cooling is slow enough to allow the reaction to take place. The same is true for all bulk liquid agent destruction processes that use high temperatures and then provide for cool down of the reaction products to ambient temperatures. A measure of the significance of these considerations may be gained by reviewing the JACADS operating experience. Although the level of production inside the current JACADS furnaces and related afterburners is not known, the immediately downstream pollution abatement systems axe designed to minimize subsequent chlorinated dioxin production conditions by using a water quench to rapidly cool the gases to about 60°C and then remove both HCl and Cl2 by contact with a sodium carbonate solution. Analysis of the exhaust gases from the JACADS systems has shown little evidence of significant residual chlorinated dioxins. However, traces of chlorinated dioxins were found in the stack emissions when projectiles containing high residuals of HD were heat treated in the metal parts furnace. Under these conditions the quantity of chlorinated dioxins varied from 0 to 0.16 ng/m3, more than an order of magnitude less than emitted from municipal incinerators (MITRE Corporation, 1993). The low-temperature chemical and biological processes axe not expected to form chlorinated dioxins because the recombination temperature conditions will never exist. Subsequent filtering for particulate removal or storage of effluent gases at approximately 120°F, such as would exist after passing through a water-scrubbing pollution abatement system, is not expected to form additional chlorinated dioxins. In fact, the use of activated charcoal filters would be an effective method for further removal of chlorinated dioxins. While the production of chlorinated dioxins should be minimized, and subsequent removal methods should be provided, periodic monitoring for the their presence would also be prudent. MONITORING The detection of chemical warfare agents at extremely low concentrations is difficult in practice for several reasons (NRC, 1993): There axe several agents in the U.S. stockpile, GB, VX, and HD (mustard), with different characteristics. All axe complex organic compounds without an identifying characteristic that allows easy and rapid identification. The agents may be masked by, as well as mistaken for, other organic compounds that happen to be present in higher concentrations.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions In the current Army method of analysis, air samples are collected by withdrawing a small air stream from the process stream, the atmosphere, or air adjacent to potentially contaminated material. This air stream is then passed through a sample collection robe, where organic components are deposited on an absorbent medium. For quick analysis of limited sensitivity, sample collection time may last only a few minutes. For the detection of smaller quantifies of agent, the amount of sample collected must be larger, and the collection time may be several hours. This sample is then desorbed into a gas chromatograph with a flame photometric detector. The minimum level of detection now used for all agents is very small, about 20 percent of the maximum allowable concentration for uncontrolled access (Table 4-1). Although the maximum allowable concentration of agent is 3 ng/m3, the minimum detectable amount for several hours of collection time is about 0.6 ng/m3. As noted above, for GB this is equivalent to about 2.6 × 1012 molecules/m3. The Army requirement to detect these very small quantities (Table 4-1) leads to many false positives, more than found with less sensitive measures, bemuse the instrumentation detects other similar organic compounds that emerge from the chromatographic column at the same time as agent. Especially for future operations in the continental United States, false alarms should be minimized because of the delays for retesting and other associated problems. The storage of gas emissions will allow time for the analysis required for certification (see Chapter 5). However, improved test reliability as well as sensitivity is highly desirable. The NRC recently discussed with the Army the conduct of farther R&D on the use of agent-specific mass spectrometry, which should decrease both false positives and analysis time (NRC, 1993). The existing gaseous-waste monitoring equipment was developed for use on well-oxidized gases saturated with water vapor. Selection of any alternative technology would require further development of early monitoring equipment if other components, such as incompletely oxidized hydrocarbons or sulfur compounds, are present to any significant degree. In addition, any alternative technology will need to have its own monitoring capability for process control, the nature of which must match the chemistry and physics of the specific internal process steps needing control. Although these are readily available for many measurements, a review of the specific requirements and equipment availability should be made before any selection is finalized. Any requirement for invention of monitoring equipment would involve a high risk.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions EFFLUENT RETENTION TIME REQUIREMENTS Further reduction of the risk of potential releases of agent or air toxics to the atmosphere could be accomplished in three ways: store and test gaseous waste streams before release, use activated-carbon beds (charcoal filters) to capture organic matter contained in the gaseous effluents, and reduce gaseous effluents by conversion to solids. The baseline system does not currently store and test (storage and certification) gaseous effluents before release to the environment. To ensure that an effluent waste stream is safe for disposal requires a retention time including time required for analyses and certification plus time to shut down all inputs to the effluent stream safely if the analyses determine that the waste stream exceeds specified standards. It takes several minutes to perform normal operational analyses (up to 20 minutes if repeat analyses are required) and several hours to collect and analyze samples from the site boundary. Although more nearly real-time analyses may be possible in the future, the times cited reflect actual current baseline capability. The time required to terminate process operations and to stop the effluent stream varies depending on the operations involved. Some processes may be shut down almost instantaneously, but most will require more time. For example, any thermal process may be shut down instantaneously by shutting off the agent feed stream, rapidly removing the greatest contamination source. However, if the system design requires the feed system to be kept hot, and if doing so requires the continued feeding of an alternative (if innocuous) fuel in place of chemical agent, there will be continuing flow of material through the contaminated system, which may take tens of minutes or longer to stop production of additional contaminated waste stream. Because combustion chambers and gas cleanup systems are both potential contamination sources, the continuing gas waste stream will also require analysis before its release. Using the existing metal parts furnace to evaporate and pyrolyze agent that has been polymerized and cannot be drained from the ton containers or projectiles continues to produce contaminated wastes until all of the agent is destroyed because the system remains hot for hours. Should storage and certification be implemented, all process waste streams should be retained for at least 1 hour (preferably up to 8 hours),-to provide adequate time to certify their acceptability for uncontrolled release to the atmosphere (see Chapter 5). Charcoal beds could be used to capture any organic materials, including agent, that might be in the gaseous waste streams. These charcoal filters would in effect store such compounds. An alternative to storage and certification would be to convert the waste stream to a form easily stored for long periods of time. For example, all
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Alternative Technologies for the Destruction of Chemical Agents and Munitions carbon atoms might be converted to CO2, which could be liquefied and stored or converted to a salt (calcium carbonate). TIME REQUIRED FOR TECHNOLOGY DEVELOPMENT AND DEMONSTRATION Any use of an alternative technology for chemical weapons destruction would require that it be fully developed and demonstrated, requiring a corresponding extension of the current destruction schedule. No alternative technology was eliminated from consideration here because of the time required for its full development and demonstration. Time estimates are presented below for any technology to go from concept through demonstration stages. Each technology was evaluated for its current status with respect to this standard. Although generic time estimates are useful in assessing the technological options, the actual development time required for any option would depend strongly on such variables as the difficulties encountered, the level of effort, and the capability of the group carrying out the program, as well as other factors discussed below. The following steps must be taken in developing any new destruction technology: Concept development. Time required for concept development is an unknown, often depending on invention. No time is estimated in this report for any technology still in concept development. Laboratory data development. Bench-scale tests and experiments are required to determine chemistry and kinetics. Concept design. This phase includes the development of flow sheets, heat and material balances, equipment design and selection, and schedule and cost estimates. Pilot plant. Test needs and plans are developed for a pilot plant. This step requires time to design, obtain permits, construct, test, operate the pilot plant, and evaluate performance data. Demonstration. Demonstration entails design, obtaining permits, constructing a facility, and conducting tests equivalent to the Operational Verification Testing (OVT) recently completed at the Johnston Island facility. Such tests, with agent, would be conducted in a special facility, such as the Chemical Agent Munitions Disposal System (CAMDS). Production (destruction) facility. Bringing the final destruction facility on line will require design, obtaining permits, construction, start-up, and the beginning of operations.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions Table 4-2 presents estimates of the time required for these steps on the basis of input from various outside sources, including Army estimates made at the committee's request (Baronian, 1992a,b; see Appendix C) and the experience of committee members in industrial applications. The development of a major new technology from the stage of lab data development through demonstration would likely take 9 to 12 years. Development times could be delayed or accelerated by a number of factors beyond those noted above. The development schedule might be delayed by the absence of DOD pilot testing facilities, delays in obtain g permits, and additional requirements associated with the handling of chemical warfare agents, including personnel training. Thus, development time would not be so much a question of technology limitations; these further time delays might also raise issues of public acceptance and obtaining permits for pilot processes that have not been previously demonstrated. The time to produce a production facility would probably be similar to that for the existing program, with design, construction, and systematization requiring about 5 years (see Table 1-1). The time requirements indicated in Table 4-2 are typical for a new technology with a separate stand-alone development program and no program overlapping. Development times could be shortened if any of several conditions is met: The technology is only a small modification of an existing, fully developed, commercial technology. Use of a modified JACADS might be possible, but only if it did not interfere with production run requirements. For a demonstration, only minor changes are required to an existing facility. The Army is willing to overlap some steps that might normally be done sequentially (probably at substantial additional cost risk). The required scale of the destruction facility is small enough that a decision could be made to omit intermediate-scale, pilot plant studies and to proceed directly to full-scale development and demonstration. As Table 1-1 suggests, the Army expects to begin construction of the last planned facilities in January 1995. However, reaching agreements with local communities, design, and obtaining permits could easily consume the 2 years from the time of this writing until then. Even though 2005 is the completion date for stockpile destruction, there may not be enough time for new technologies to replace the current baseline technology and meet the destruction target date.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions TABLE 4-2 Time Estimates for Development and Demonstration of Alternative Technologies Development/Demonstration Stage Approximate Time Required Laboratory data development A minimum of 1 to 2 years if major problems not encountered; longer if related data not available Conceptual design 0.5 years (could overlap laboratory work) Pilot plant 0.5 to 1 year for design 2 years to apply and obtain permits 0.5 years to construct 1 to 2 years to operate 0.5 years to evaluate Demonstration 1 year (or more) to design and permit 1 year to procure 1 year of OVT Total time 9 to 12 years (if related data available at concept development stage) TECHNOLOGY DEVELOPMENT AND DEMONSTRATION COSTS The use of an alternative technology would incur additional program costs both to complete development and demonstration of the technology and to account for delays in the current program. The cost of laboratory and pilot plant development will likely be significantly higher for an alternative chemical demilitarization technology than for an industrial process not involving lethal chemical agent. Special training and facilities are obviously required to work with such toxic chemicals. Furthermore, it is unlikely that
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Alternative Technologies for the Destruction of Chemical Agents and Munitions test work will be performed in university, national, or commercial development laboratories not currently equipped to work with agent.3 Note that the greatest part of facility costs is accounted for by the frontend reverse assembly function and related safety concerns. The costs for the actual destruction process equipment are a relatively small part of total system costs. Thus, the functional capability of any unit process to destroy chemical agent, without introducing new waste problems, is likely to be much more important than the equipment costs. Some potential alternative technologies would require the use of large amounts of energy, such as for the production of a plasma arc and the heat to dry salts. These energy requirements are very important to the economic viability of other waste disposal methods when disposal costs are measured in terms of a few dollars per pound. However, the cost for the total program to destroy chemical agents amounts to about $120 per pound (or $6 billion to destroy 25,000 tons). Thus, energy costs will be much less important than the capability to destroy agent. Finally, it is possible that useful by-products from chemical weapons disposal facilities could be collected and sold to reduce program costs. The committee believes this consideration to be of secondary importance: buyers would not pay normal market prices because of potential liability and public perception problems, and the income generated would at most pay only for the disposal of these specific materials, allowing for no profit. ASSESSMENT CRITERIA FOR ALTERNATIVE TECHNOLOGIES The committee evaluated potential alternative technologies on the basis of development status, functional performance, and engineering factors.4 Development status. As discussed previously, level of development is an important criterion in this technology assessment. Also of importance is whether a technology has ever been applied to chemical agent. Categories used in the committee's analysis are the following: 3 As for estimates of development time, the Army has suggested a generic approach to estimates of program costs (Baronian, 1992a,b). This Army approach assumes the use of an already well-developed technology, further laboratory and pilot testing at the CAMDS facility, no demonstration, and construction of full-scale destruction facilities. The Army estimate is approximately $880 million dollars but does not include savings from elimination of the baseline technology. It is not specific to any given technology. 4 In some cases, where information is common to closely related technologies or where data are not available, only a summary statement may be made without reference to each technology developer listed in Appendix E.
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Alternative Technologies for the Destruction of Chemical Agents and Munitions concept only: adequate data base does not exist; laboratory stage: initial data encouraging but not complete; pilot plant stage: small plant operative with data collected for scale-up; in commercial operation for similar applications; and prior experience in destroying one or more agents. Functional performance. It is important to assess a technology's capability to perform one or more of the functional steps needed to destroy chemical weapons. treatment capability and attributes (for each chemical agent)—The assessment must include consideration of the ability to treat liquid agent, metal parts, propellants and explosives, dunnage, and air streams. It also must determine the technology's likely level of agent destruction (whether it is useful for pretreatment or for other degrees of destruction). waste treatment requirements-Each technology should be assessed for the likely solid, liquid, and gaseous waste streams it would generate and the requirements for further treatment. Engineering factors. Various engineering factors must be considered that may significantly influence the effectiveness of a technology, its potential for failure in development, and its safety or hazard potential under operation. Such engineering factors include pressure, temperature, corrosion, stability of operation (rate, control), explosion potential, inventory requirements, and potential for human error during operations.
Representative terms from entire chapter: