DEVELOPMENT OF A WASTEWATER MANAGEMENT SYSTEM FOR
AN ELEMENTAL PHOSPHORUS PRODUCTION PLANT
John H. Koon, Vice President/Technical Director
Gary M. Davis, Process Engineering Manager
Associated Water and Air Resources Engineers, Inc.
Nashville, Tennessee 47204
Paul D. Knowlson, Manager
Phosphorus Division
Hooker Chemicals & Plastics Corporation
Niagara Falls, New York 14302
Edward F. Smith, Superintendent of Environmental Affairs
Hooker Chemicals & Plastics Corporation
Columbia, Tennessee 38401
INTRODUCTION
The Hooker Chemicals and Plastics Corp. manufactures elemental phosphorus (P4) and
phosphoric acid (75% H3P04) from phosphate ore at a plant located near Columbia,
Tennessee. The elemental phosphorus production process requires the use of large quantities
of water, principally for scrubbing gas streams and for cooling. Wastes generated in the
production of phosphorus typically contain large quantities of suspended solids, phosphates,
fluorides and elemental phosphorus, which is toxic to aquatic life. The wastewater management system which existed at the Hooker plant prior to the beginning of this investigation
incorporated treatment of wastewaters using lime, storage of the water in onsite ponds,
and recycle of water to process uses. This system was very effective during dry weather
periods in which the consumptive use of water in the plant exceeded the quantity of water
used from outside sources.
However, significant problems were experienced during rainy periods due to the collection of large volumes of stormwater runoff into the plant water supply system. This situation became most unacceptable due to the plant topography and middle Tennessee climate.
The topography of the area around the Columbia plant is typified by ridges and hUls that
are 300 to 360 ft higher than the elevation of surface water in the area. Land surface elevations range from approximately 520 to 880 ft above sea level. The slope of the land ranges
from approximately 8 to 20%. The plant is located on 110 acres of land which drops approximately 150 ft from its highest to its lowest elevation. The process area is located at the
bottom of this hdly terrain. Thus, during intense rain storms, an enormous amount of
water cascades down onto the process area. The rapid runoff of stormwater from the plant
areas resulted in the inundation of pump stations and surge ponds during periods of intense,
prolonged rainfall, and overflows of the combined stormwater runoff and process wastewaters occurred. The capacity of the plant water storage system was stressed most heavily
in handling storm runoff during the winter months when evaporation from the storage
ponds is at a minimum compared to evaporation rates during the summer. The normal
rainfall for the Columbia area is 52 in./yr, which is spread somewhat evenly throughout
the year. On the other hand, the annual evaporation is approximately 31 in./yr at Columbia
and varies considerably from a maximum during summer months to minimum values during
the winter. Climatological factors make control of stormwater runoff from this plant which
covers some 110 acres difficult.
In order to upgrade the water management system at the Columbia plant, Hooker embarked on a program to develop a system to segregate uncontaminated stormwater runoff
from the plant water system, convey the combined stormwater and process wastestreams
to storage ponds, and to develop a treatment system capable of processing these waste
streams for reuse or for discharge to a surface waterway.
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