Transportable Hot-Gas Decontamination System at the Alabama Army Ammunition Plant Site, Alpine, Alabama

Site Name:

Alabama Army Ammunition Plant


Alpine, Alabama

Period of

December 4, 1995 to March 15, 1996


Demonstration and validation tests


Roy F. Weston, Inc.
1 Weston Way
W. Chester, PA 19380


L&L Special Furnace Co., Inc.
Aston, PA

Transportable Hot-Gas Decontamination (HGD) furnace
- natural gas or propane-fired, box-type furnace with integrated ceramic-fiber lining
- manually loaded and unloaded batch process
- furnace components are skid mounted, approximately 16 ft by 8 ft
- heated by 1 million Btu per hour, high velocity nozzle-mix Eclipse Burner equipped with UV sensor and Industrial Risk Insurers (IRI) class gas safety system
- combustion air to burner set at a fixed rate that maintains excess air capacity to promote lower furnace chamber temperatures between 300 and 600° F
- capacity to treat 3,000 lb of contaminated materials
- gases directed into thermal oxidizer combustion chamber

Cleanup Authority:
Validation test conducted under guidelines for treatability studies.

Chlorinated Explosives contaminated materials and debris, including TNT-, RDX-, and Tetryl-contaminated materials

Waste Source:
Contamination of process-related equipment, sewers, piping, and structures resulting from manufacture, storage, testing, and disposal of explosives

Type/Quantity of Media Treated:
Explosives-contaminated piping and debris

Purpose/Significance of Application:
Demonstration and validation testing to determine effectiveness of treating explosives-contaminated materials using the Hot-Gas Decontamination System

Regulatory Requirements/Cleanup Goals:
No permitted limits for system emissions or operating conditions for this demonstration.

- Verified effectiveness of HGD system equipment in decontaminating explosives.
- Defined optimum processing times and temperatures for TNT-, RDX-, and Tetryl-contaminated materials.
- Collected air emissions data to support future system permitting efforts.
- Achieved complete removal of TNT, RDX, Tetryl, and their breakdown constituents to levels below method detection levels (250°F/hour ramp to 600°F treatment temperature with a 1-hour goal).

Cost Factors:
- Total capital equipment cost of the HGD system was $689,500.
- Total operating costs were $3,337.
- Total estimated validation costs are approximately $90,000.

The United States Army Environmental Center (USAEC) has been conducting laboratory investigation and pilot-scale studies of the hot-gas decontamination (HGD) process since 1978. The results from these investigations and studies verified the effectiveness of the HGD technology for treating chemical agents and explosives, however, post-test recommendations indicated that equipment designed specifically for the HGD concept would improve system efficiencies and process optimization goals. As a result, USAEC contracted the design and procurement of system equipment specifically for the treatment of explosives-contaminated materials by the HGD process. The resultant equipment design was delivered to USAEC's test site at the Alabama Army Ammunition Plant (ALAAP) located in Alpine, Alabama for demonstration and validation testing.

The demonstration and validation testing was conducted between December 4, 1995, and March 15, 1996. System trials proved the HGD Equipment to be fully functional and capable of maintaining anticipated treatment temperatures. The HGD Equipment system was optimized to enable the complete destruction of explosives contamination at a furnace ramp rate of 250°F/hr, treatment temperature of 600°F, and a treatment time of 1 hour. In general, the HGD system is designed to meet all applicable regulatory performance standards contained in following sections of 40 CFR:

- RCRA incinerator standards (40 CFR, Part 264, Subpart 0)
- Miscellaneous Unit Standards (40 CFR, Part 264, Subpart X)
- Boiler and Industrial Furnaces Standards (40 CFR, Part 266, Subpart H
- TSCA incinerator standards (40 CFR, Part 761.70 (b)