Appendix F
Explosive Destruction System Phase 1 (EDS-1) Overview and Description

INTRODUCTION

The EDS is a transportable system designed to treat chemical munitions under three scenarios:

  • at chemical munition recovery locations when a chemical munition is deemed unsafe to transport by vehicle or store by routine means at the time of recovery

  • at chemical munition storage locations when a previously recovered chemical munition is determined not to be safe for continued storage

  • at locations that have a limited number of chemical munitions (with or without explosive components) that can be treated in the EDS when the quantities do not justify the use of other destruction systems

The mission of the EDS is to destroy explosively configured chemical warfare munitions, contain the blast and fragments in opening the munition, and treat the chemical fill of the munition, in an environmentally friendly manner. The EDS is intended for use with World War I and World War II vintage chemical warfare materiel (CWM) produced before 1945. Post-World War II munitions have larger bursters that exceed the capacity of the system.

OVERVIEW OF EXPLOSIVE DESTRUCTION SYSTEM

The operational scenario for the EDS consists of Explosive Ordnance Disposal personnel hand-carrying the recovered munition and placing it in the EDS containment vessel. Once the munition is enclosed in the EDS, the conical and linear shaped charges are initiated to explosively open the munition and detonate the burster. Reagents are then added to treat the chemical agent. The treatment process relies on chemistries developed by the U.S. Army for the various chemical agents. The effluent, if defined as hazardous waste, is managed in accordance with state and federal requirements and the system is prepared for the next munition.

The EDS, shown graphically in Figure 1–1, includes the following major components:

  • the trailer on which the entire system is mounted

  • the explosive containment vessel that contains the blast, fragments, and chemicals

  • the explosive accessing system that cuts the munition with a linear shaped charge and attacks the burster with two conical shaped charges

  • the fragment suppression system that protects the containment vessel from high-velocity fragments

  • the firing system that fires the detonators on the shaped charges

  • the chemical storage and feed system that supplies reagents and water to the containment vessel

  • the waste handling system that drains the treated effluent and vents vapors from the containment vessel (includes vapor sampling and carbon filtration of effluent vapors)

  • the vessel hydraulic oscillation system that mixes the contents of the containment vessel to ensure complete treatment of the chemical agents

  • the electrical instrumentation and control system.

EXPLOSIVE DESTRUCTION SYSTEM TRAILER

The EDS is mounted on an open flatbed trailer, making the system transportable for rapid response in emergency situations. The 2.6 meter by 6.1 meter, tandem-axle trailer weighs about 7,260 kg and has a rating of 8,160 kg. The trailer height for shipping is 2.4 meters.

The working surface of the trailer is about 0.3 meters above the main trailer structure, or about 1 meter above the ground. The working surface has an open grid over a stainless steel secondary containment pan. Stainless steel is used for compatibility with agents and reagents.

   

NOTE: This appendix is adapted from DiBerardo and Haroldsen (2000).



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Evaluation of Alternative Technologies for Disposal of Liquid Wastes from the Explosive Destruction System Appendix F Explosive Destruction System Phase 1 (EDS-1) Overview and Description INTRODUCTION The EDS is a transportable system designed to treat chemical munitions under three scenarios: at chemical munition recovery locations when a chemical munition is deemed unsafe to transport by vehicle or store by routine means at the time of recovery at chemical munition storage locations when a previously recovered chemical munition is determined not to be safe for continued storage at locations that have a limited number of chemical munitions (with or without explosive components) that can be treated in the EDS when the quantities do not justify the use of other destruction systems The mission of the EDS is to destroy explosively configured chemical warfare munitions, contain the blast and fragments in opening the munition, and treat the chemical fill of the munition, in an environmentally friendly manner. The EDS is intended for use with World War I and World War II vintage chemical warfare materiel (CWM) produced before 1945. Post-World War II munitions have larger bursters that exceed the capacity of the system. OVERVIEW OF EXPLOSIVE DESTRUCTION SYSTEM The operational scenario for the EDS consists of Explosive Ordnance Disposal personnel hand-carrying the recovered munition and placing it in the EDS containment vessel. Once the munition is enclosed in the EDS, the conical and linear shaped charges are initiated to explosively open the munition and detonate the burster. Reagents are then added to treat the chemical agent. The treatment process relies on chemistries developed by the U.S. Army for the various chemical agents. The effluent, if defined as hazardous waste, is managed in accordance with state and federal requirements and the system is prepared for the next munition. The EDS, shown graphically in Figure 1–1, includes the following major components: the trailer on which the entire system is mounted the explosive containment vessel that contains the blast, fragments, and chemicals the explosive accessing system that cuts the munition with a linear shaped charge and attacks the burster with two conical shaped charges the fragment suppression system that protects the containment vessel from high-velocity fragments the firing system that fires the detonators on the shaped charges the chemical storage and feed system that supplies reagents and water to the containment vessel the waste handling system that drains the treated effluent and vents vapors from the containment vessel (includes vapor sampling and carbon filtration of effluent vapors) the vessel hydraulic oscillation system that mixes the contents of the containment vessel to ensure complete treatment of the chemical agents the electrical instrumentation and control system. EXPLOSIVE DESTRUCTION SYSTEM TRAILER The EDS is mounted on an open flatbed trailer, making the system transportable for rapid response in emergency situations. The 2.6 meter by 6.1 meter, tandem-axle trailer weighs about 7,260 kg and has a rating of 8,160 kg. The trailer height for shipping is 2.4 meters. The working surface of the trailer is about 0.3 meters above the main trailer structure, or about 1 meter above the ground. The working surface has an open grid over a stainless steel secondary containment pan. Stainless steel is used for compatibility with agents and reagents.     NOTE: This appendix is adapted from DiBerardo and Haroldsen (2000).

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Evaluation of Alternative Technologies for Disposal of Liquid Wastes from the Explosive Destruction System The containment vessel is mounted over the axles of the trailer with the door facing the front of the trailer. The water and reagent tanks are at the front of the trailer. The area between these components serves for preparing and loading the munition. All controls and instrumentation displays are readily accessible from this working area. The electrical supply panels and the hydraulic pump are mounted at the rear of the trailer. Piping and electrical conduit run under the main deck. EXPLOSIVE CONTAINMENT VESSEL The purpose of the explosive containment vessel is, first, to contain the explosive shock, fragments, and chemical agent during the munition opening process and then to serve as a process vessel for the subsequent chemical treatment of the agent. The 189-liter cylindrical vessel and door were fabricated from two 316 stainless steel forgings. The inside diameter is 51 cm with 5.1-cm-thick walls. The vessel is designed to contain at least 500 detonations of up to one pound (0.45 kg) of explosive TNT equivalent. The hinged door is the same diameter as the vessel, allowing easy access for inserting munitions and removing debris. The door is secured with two large clamps that are in turn secured with four threaded rods with hydraulic nuts. The vessel relies on a Grayloc all-metal seal to contain the detonation and the chemical agent. An o-ring provides a backup seal and aids in leak testing. ACCESSING MUNITIONS WITH SHAPED CHARGES Details of the system for accessing munitions in the EDS-1 are given in Table F-1. Once the munition has been placed in the EDS vessel, the contents of the munition must be exposed and the burster destroyed before the chemicals can be treated. This is accomplished with a combination of linear and conical shaped charges. Shaped charges were chosen over mechanical, chemical, and thermal mechanisms because they require minimal access through the containment vessel wall, they are exceptionally reliable, and their design is well characterized. A single preformed length of copper linear shaped charge (LSC) is used to open the main body of the munition and expose the contents for treatment. The LSC is designed to make a complete cut in the munition, separating it into two pieces and fully exposing the chemicals within. Detonators are connected to the LSC at each end for increased reliability. Two copper conical shaped charges (CSC) are used to break open the burster charge canister in the munition and detonate the burster explosives. The CSCs are fired in the direction of the burster at the same time as the LSC is fired. The CSC is a multi-tapered copper device containing 32 grams of Composition A explosive. It was selected because it meets the initiation requirements of TNT and the need for precision and repeatability. The CSC design was chosen to exceed the criteria for reliable detonation of the burster explosives by shaped charge impact. However, because the condition of the explosives in aged, recovered munitions is inherently uncertain, detonation of the burster cannot be guaranteed. For safety, exploding bridge-wire (EBW) detonators are used to initiate the shaped charges. These detonators are very insensitive to unexpected or undesirable energy inputs (static, impact, etc.). Four electrical feed-throughs are in the containment vessel door for the high-voltage EBW detonators. A steel plate is mounted in front of the feed-throughs to protect them from direct impact during the explosion. FRAGMENT SUPPRESSION SYSTEM The recovered munition and the shaped charges are placed in a fragment suppression system (FSS) before being loaded into the containment vessel. An FSS is necessary to mitigate high-velocity fragments that could damage the interior of the EDS vessel during operations. Fragments will come from the LSC, the CSCs, the burster charge case, and the munition itself. The core of the FSS is a steel cylinder separated lengthwise into two sections. The cylinder is connected to a cradle that supports the system inside the EDS vessel. A three-sided steel support is positioned inside the lower half of the cylinder to hold the munition and to provide shock absorption below the munition. A steel block is positioned between the lower half cylinder and the cradle bottom to stop the CSC jet in case of complete penetration. The LSC and CSCs are attached to the lower and upper halves of the FSS for ease of assembly and to maintain the correct standoff distance. FIRING SYSTEM AND DETONATORS The firing system initiates the LSC and CSC burster charges. The firing system is a high-voltage capacitor discharge unit (CDU) capable of reliably firing four detonators (1.5×40 mil EBW) over cable lengths of up to 15.2 meters. The firing system is modular so that parts can be tested and replaced easily. The firing system consists of a CDU, a high-voltage trigger module, a high-voltage power supply, a control module, monitoring and diagnostics equipment, and safety controls. The entire system can be operated from an easily accessible panel. A redundant system is mounted in the same panel. A high-potential breakdown tester is mounted on the panel to enable testing of the cables and feed-through connectors associated with the firing system. CHEMICAL TREATMENT The EDS uses a low-pressure, low-temperature chemical treatment method to reduce the hazardous properties of the chemical agents so that the resulting waste can be disposed

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Evaluation of Alternative Technologies for Disposal of Liquid Wastes from the Explosive Destruction System TABLE F-1 System for Accessing Chemical Munitions Element Purpose Description/Configuration Linear shaped charge (LSC) Open main body of munition and expose the contents for chemical treatment. Preformed lengths of RDX-based, copper- sheathed LSC. The shape and length of the LSC is specific to the type of munition being destroyed. Conical shaped charge (CSC) Puncture the burster in the munition and attempt to detonate the burster explosive. The CSC consists of 32 grams of Composition A-3, multitapered and copper-lined. Depending on the munition, one or two CSCs are used. Fragment suppression system (FSS) Absorb shock from high-velocity fragments, thus preventing damage to the interior of the EDS vessel. Fragments are generated from the LSC, the burster casing, and the munition itself. The core of the FSS is a mild steel cylinder separated lengthwise into two sections. A three-sided steel support is connected to the bottom cylinder section to center the munition and provides shock absorption in the downward direction. Cylinder endplates absorb shock and protect the ends of the EDS vessel. Firing system and detonators Simultaneously initiate the LSC and CSC charges. Reynolds type RP-85 EBW detonators for LSC. For CSCs, Reynolds type RP-1 and RP-2 EBW detonators are used. These contain RDX explosive.   SOURCE: U.S. Army (2000). of at commercial hazardous waste facilities. The process, which is referred to as neutralization, relies on chemistries developed by the Army. Treatment is done inside the containment vessel after the munition is opened to prevent transfer or release of untreated chemical agent. Three 95-liter, stainless steel tanks provide short-term storage for water and reagents used for chemical treatment. The liquids are pumped from the tanks to the containment vessel. The pump is mounted directly below the tanks. The tanks are heated to make viscous liquids easier to pump and to speed the treatment process. A valve panel on the vessel door allows the operator to control the transfer of reagent or water, collect samples for chemical analysis, and drain the liquid effluent. Each port has redundant valves. The high-pressure valves have metal-to-metal seals and Teflon packing. Near the top are two spray nozzles for injecting the reagents and collecting gas samples. Liquid samples are collected through the dip tube that extends to the bottom of the vessel. After treatment, the effluent is drained to standard 55-U.S. gallon (208-liter) drums through two sieved ports near the bottom of the door. Liquid effluent is collected in the drums, while gaseous overpressure is vented through a silica gel/ASZM-TEDA carbon filter. The waste handling system includes secondary spill containment for the drums, scales to measure liquid content, and pressure relief rupture disks. HEATING AND OSCILLATION SYSTEM The speed of treatment is limited by the solubility of the chemical agent in the reagent. If the agent has polymerized or degraded, treatment may be prolonged. Inorganic chlorides may yield copious precipitates of oxides/hydroxides under these conditions, so agitation and excess reagent are required. In the EDS, the vessel can be heated to near the boiling point of the reagents and agitated to accelerate the reactions. Since any hardware inside the vessel must withstand the explosive detonation, the vessel is externally heated and agitated. The vessel uses 12 1-kW band heaters with a feedback control system. The reagents are heated to about 60°C before they are injected into the vessel. It takes about 2 hours to heat the contained fluids to 100°C. Fluid temperature can be controlled within ±4°C. The vessel is mounted on pillowblock bearings, allowing it to tilt forward and backward. A hydraulic system oscillates the vessel between ±40 degrees from the horizontal position. The entire stroke through 80 degrees takes about 15 seconds. The vessel can be stopped in any position to aid in draining or sample collection. ELECTRICAL INSTRUMENTATION AND CONTROL SYSTEM Two control and instrument panels are mounted at the front of the trailer near the water and reagent tanks. One panel contains pressure and level displays and pump controls. The second panel contains temperature readout and controls. Controls for the hydraulic oscillation system and hydraulic nuts are in a panel on the side of the trailer. Two electrical distribution panels at the back of the trailer contain circuit breakers and other electrical equipment.