US Navy combats shipboard incineration and
waste disposal problems

By J.A. Cole, D.W. Hansell, N.C. Widmer, Wm. R. Seeker,
Energy and Environmental Research Corporation, Irvine, California
(EER has a Canadian office in Markham, Ontario);
K. J. Wilson, T.P. Parr and K.C. Schadow,
Naval Air Warfare Center, Weapons Division, China Lake, CA

As the US Navy moves into the 21st century, both international and domestic regulations will drive changes to more environmentally responsible operation of Naval ships. MARPOL1 and the Environmentally Sound Ships program are examples of regulations that will eventually ban such common practices as at-sea dumping of waste paper, food, scrap, and human wastes.

navy
USS Constellation ready for action. US Navy Photo

Unfortunately, naval ships, unlike vacation cruise ships, are designed to maximize their primary function, which is to protect national interests at sea and in extreme circumstances engage in warfare. This means that there is little room available for installation of incinerators and associated waste handling and processing equipment. This incongruity between desirable waste handling practices and the primary mission of naval ships is driving the development of more compact hardware and advanced technologies for at-sea treatment of shipboard-generated wastes.

Incineration, or more politically, waste thermal treatment, is a preferred method for waste handling. It can accomplish several of the goals of at-sea treatment of shipboard wastes, including volume reduction, sterilization, and detoxification. It is also considered to be the most cost-effective approach available and among the safest, requiring little specialized personnel training.

Unfortunately neither land-based nor existing seaworthy incinerator designs can meet the Naval requirements of compactness and light weight. This has led to the exploration of novel approaches, such as the use of forced acoustics to improve heat transfer, turbulent mixing, and firing density in order to reduce the size and increase the throughput of incineration systems.

1MARPOL refers to three international treaties: The Convention for the Prevention of Marine Pollution by Dumping from Ships and Aircraft, adopted at Oslo on 15 February 1972; The International Convention for the Prevention of Pollution from Ships, 1973, adopted at London on 2 November 1973; and The Protocol of 1978 Relating to the International Convention for the Prevention of Pollution from Ships, 1973, adopted at London on 17 February 1978.

This article has been abridged.