Biological Treatment For World's Largest Acrylate
Plant to Achieve BATEA on Houston Ship Channel
CARL E. ADAMS, JR., President
GARY M. DAVIS, Project Engineer
Associated Water and Air Resources Engineers, Inc.
Nashville, Tennessee 37204
BACKGROUND INFORMATION
A new organic chemical plant is presently being constructed by a leading chemical
manufacturer. This plant will be the largest one of its type in the world, generating greater
than 40 percent of the total world production. The major products will be a variety of esters.
Since the production plant is to be a new, "grass roots" operation, conscientious efforts
have been made to modify production processes and to install in-plant methods for
maximum recovery, reduction, and concentration of wastewater constituents which may be
discharged to the sewer. These extensive in-plant efforts have resulted in a projected
aqueous wastestream having a very high strength and low volume.
Due to the location of the plant on a quality limited stream and the character of the
wastestreams, it was recognized that Best Available Treatment Economically Achievable
(BATEA) would probably prevail and that sophisticated treatment techniques might be
required to meet the anticipated water quality discharge requirements. Associated Water
and Air Resources Engineers, Inc. (AWARE, Inc.) of Nashville, Tennessee was retained by
the company to develop a wastewater management program for the residual aqueous
process wastes from the proposed production facility. AWARE was to evaluate potential
physical-chemical and biological treatment processes and recommend possible methods
which would provide the best available technology to successfully treat the anticipated
wastewaters.
WASTEWATER CHARACTERISTICS
Due to the comprehensive in-house program of segregating all clean water systems, the
resulting wastewaters were estimated to be of extremely high strength. Because of these in-
house efforts, two major wastes were generated and are designated as Waste Liquid No. 1
and the Chemical Sewer. The Waste Liquid No. 1 is an aqueous phase which is separated
from the crude organic acid during production. This stream has an average BOD of
approximately 23,000 mg/l at a waste flow of 0.460 mgd. The Chemical Sewer waste
originates primarily from an esterification section of the plant and contains alcohol stripper
bottoms, jet condensate, plant washdown, and non-avoidable drips and spills. This stream
was projected to have a BOD of 9,570 mg/l and a flow of 0.305 mgd. The specific organic
constituents in the wastewater varied depending on which of several esters was being
produced, i.e., methyl, ethyl, or butyl. The Waste Liquid No. 1 was composed primarily of
acetic acid with small quantities of formic acid and some formaldehyde.
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