Lignite-burning power plants often used dirt-lined or clay-based pits to store wastes such as carbon-containing acids, or inorganic acids and caustics. However, such pits are now believed to provide insufficient protection for corrosive applications.
Houston Light & Power now installs fiberglass-lined concrete storage basins for corrosive waste applications, according to Dale Wright, lead engineer for utility’s Limestone plant in Jewett, Tex. One of the basins at Limestone is an organic retention pond that contains mostly organic cleaning waste. The largest pond (300 x 300 ft) is for inorganics that contain some metal cleaning waste. There is also a chemical equalization basin for demineralizer wastes and other chemical wastes.
“Based on previous experience at our Parish power plant, we believe fiberglass-lined concrete basins are the best suited for this type of application,” says Lewis Chatey, a project specialist for HL&P. DERAKANE 411-45 vinyl ester resin from Dow Chemical Co. was selected as the liner material for its chemical resistance, elongation and workability properties in elevated temperatures. The surface temperature at the time of construction sometimes exceeded 110 F.
Wil-Cor, Inc. of Houston, the fabricator for the basins, developed special expansion joints to prevent water and acid migration through existing joints and to accommodate concrete contraction as much as one inch.
Reprinted from the August 1988 edition of Power Engineering
Copyright 1988 by PennWell Publishing Company