Families Against Cancer & Toxics

Plasma Arc/Plasma Waste Converter Technology:
Summary of experiences through the Assembled Chemical Weapons Assessment (ACWA) Program

Compiled by Elizabeth Crowe, Chemical Weapons Working Group

Background

In 1996, in response to growing citizen outcry against the U.S. Army’s plan to incinerate chemical weapons, the U.S. Congress passed legislation directing the Department of Defense to create a program to identify and demonstrate at least two non-incineration chemical weapons dispsoal technologies. Congress’ intent was that this program involve all stakeholders -- including citizens at chemical weapons sites and “anti-incinerator” activists -- in the decision-making process.

This Department of Defense program, called the Assembled Chemical Weapons Assessment (ACWA) program demonstrated six non-incineration technologies. However, based on criteria developed cooperatively by all ACWA participants, two technologies have been eliminated from consideration: Startech’s plasma arc system, and Teledyne Commodore’s Solvated Electron Technology.

Results of the Plasma Arc demonstration

The proposal submitted to ACWA for this technology was led by Burns & Roe, with STARTECH Environmental Corporation providing the plasma arc system.

The proposal involved using plasma waste converters (PWC) -- in which electrically driven torches produce intense radiant energy which disassociates chemical compounds.
The demonstration system included one 300-kW plasma waste converter; one gas polishing system (for pollution abatement); a liquid feed module; a box feed module; thermal oxidizers (for characterization of effluents); and an energetics deactivation chamber.

While the system did pass initial ACWA criteria, the system failed its demonstration criteria and is not under consideration for chemical weapons disposal.

The following information is taken from ACWA’s 30 September 1999 Report to Congress.

Demonstration delays

• “Delays throughout the test program were attributed to these equipment failures, system redesigns, and an inadequate design of the gas polishing system, which required frequent modifications.” p. B.4-10.
• “...by the scheduled start of the [chemical] agent campaign the operability, reliability and repeatability of the system had not been demonstrated due to equipment failures, system redesigns, and operational modifications.” At no time did STARTECH process chemical agents, as was the original plan. p. B.4-10.
• “The problems that occurred during demonstration mostly related to equipment failures.” B.4-11.

Creation of hazardous by-products

Demonstration data shows that the following hazardous substances were characterized during demonstration: formaldehyde; carbonyl sulfide; cyanide; and dioxins/furans. B.4-13.

Lacking Process Maturity

ACWA determined that while “the PWC components represent a mature technology,...the ACWA demonstration indicates that the proposed PWC configurations are not as mature as or comparable to their industrial counterparts.” p. B.4-15.

“Demonstration of the integrated PWC process raises serious concerns about the maturity of this process as proposed. Although a wide variety of materials were fed into the PWC...the continual systemization, modifications, and redesign of the process during demonstration by the provider leaves some doubt about the applicability of the test data and the capability of the demonstrated system to represent full-scale operations. Changes to operating conditions raise questions about whether or not the data were representative of the proposed process and what actual operating conditions are required; the design basis is lacking.” B.4-16.

Unstable Process Operability

“...a convincing rationale was not provided to assure stable operation at the full-scale feed rates.” “The PWC demonstrated poor reliability, availability and maintainability (RAM) characteristics with insufficient information to extrapolate acceptability to full-scale.” B.4-17.

Difficulty in Process Monitoring and Control

“...frequent variations in PWC feeds...could make the plasma arc system control strategy difficult to establish and maintain. The automatic control features proposed for the full-scale plant were not demonstrated, and further, demonstration data were not used to support the feasibility of the monitoring and control concepts proposed for the full-scale design.” B.4-19.

Insufficient Effluent Characterization; Unknown Impact on Human Health and Environment

“Consistent operating conditions were not established during demonstration....it is not possible to reliably determine the quantity of effluents, rates of emissions and discharges, constituents and concentrations of effluents, and potential for internal releases.” B.4-24.

Life Cycle Cost

“Sufficient information currently does not exist to make a reasonable estimate of the operating and maintenance costs for the plasma arc process.” B.4-26.

Since all cost considerations related to the unique chemical demilitarization program, any cost data from the ACWA demonstrations would not be directly applicable to other waste disposal proposals. That said, the costs of a plasma arc facility were estimated to be around the same as an incinerator.

Public Acceptance Criteria: Not likely!

“Based on input from the ACWA Dialogue, the plasma arc process was deemed unlikely to obtain public acceptability due to the incomplete demonstration and the perceived similarity to incineration.” B.4-27.