Biological and Carbon Adsorption Treatment of
A Refinery Wastewater
H. DAVID STENSEL, Senior Research Engineer
GERALD L. SHELL, Director of Research
Eimco Processing Machinery Division
Envirotech Corporation
Salt Lake City, Utah 84110
NEWTON DON, Senior Engineer
Atlantic Richfield Watson Refinery
Los Angeles, California
INTRODUCTION
The purpose of this paper is to describe the results of a pilot plant study at the Atlantic
Richfield Watson Refinery in Carson, California. Significant aspects of this study include
the effect of biological pretreatment on carbon adsorption and the presentation of a useful
method to evaluate activated carbon adsorption of soluble organics from wastewater.
The Atlantic Richfield Watson Refinery produces two principal wastewater streams.
One is oxidized sour water which was not concerned with in this study and the other is
process wastewater resulting from plant operations. The latter is treated by dissolved air
flotation and discharged to the sanitary sewer. During the rainy season (December thru
March), process water and storm water runoff is collected in a 50 million gallon reservoir.
This collected wastewater must be treated prior to discharge into the Dominquez Flood
Control Channel adjacent to the refinery.
Based on the expected rainwater runoff volume and storage capacity, a design
treatment capacity of 3000 gpm was determined for the wastewater treatment facility. The
Los Angeles Regional Quality Control Board limited the total organic discharge to 1330
pounds of COD per day. At the design flow rate, the effluent COD concentration has to be
37 mg/l or less.
OBJECTIVES OF STUDY
Table I shows the typical characteristics of the wastewater to be treated.
TABLE I
WASTEWATER CHARACTERISTICS
Parameter Concentration
Total COD 200-600 mg/l
Soluble COD 150-500 mg/l
Suspended Solids 10-100 mg/l
Turbidity 20- 80 J.T.U.
Oil 10- 50 mg/l
A relatively high degree of treatment is required to satisfy the effluent COD
requirement.
It had been determined by the refinery staff that an existing granular carbon unit was
not able to satisfy strict effluent requirements for therequisiteoperating period. This was
due to higher than expected COD levels of the impounded wastewaters and initial under-
design of the plant.
Therefore, the objective of the pilot plant study was to determine design parameters for
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