Treatment of Refinery Wastewater
Using Filtration and Carbon Adsorption
B.A. McCRODDEN, Conservation Engineer
BP Oil Incorporated
Marcus Hook, Penn«vlvania 19061
INTRODUCTION
A 2.2 MGD filtration carbon adsorption Wastewater Treatment Plant, placed in
operation at the Marcus Hook Refinery of BP Oil Corporation, a subsidiary of the
Standard Oil Company (Ohio), in March, 1973, has demonstrated overall removals of 76,
89, 42, 38, and 39 percent reduction for suspended solids, oil, first stage ultimate oxygen
demand (FSUOD), chemical oxygen demand (COD), and phenol, respectively.
The 105,000 BPD Class B Refinery, located in southeastern Pennsylvania, discharges
its effluent waters into the Delaware River. In 1961, the Delaware Estuary became the
subject of an intensive study by the then U.S. Public Health Service. The Delaware Estuary
Comprehensive Study (DECS) served as a basis for a determination by the Delaware River
Basin Commission (DRBC) that the 1964 discharge loads to the Estuary exceeded its
assimilative capacity. Subsequently, stream quality objectives were established and the
Estuary divided into six zones. The total first stage ultimate oxygen demand permitted to be
discharged without violating these objectives was determined for each zone from base data
developed by the DECS and its application of a mathematical model. Under thedoctrine of
equitable apportionment, each individual discharger to a zone received an allocation based
upon the concept of equal percentage of raw waste reduction in that zone. The Refinery's
measured raw waste load was 24,650 pounds per day FSUOD. Application of an 89.25 zone
percent reduction led to an overall discharge allocation of 2,650 pounds per day FSUOD.
This allocation includes the net contribution from the process wastewater and once through
cooling water streams.
An additional Delaware River Basin Commission requirement is the secondary
treatment of all process wastewater streams. Secondary treatment for zone four of the
Estuary is defined as 89.25 percent FSUOD reduction.
In 1969 a compliance schedule of 48 months was established. The initial effort toward
achieving compliance was the evaluation of the existing API oil-water-solids Separator,
through which all process wastewater flow is directed. Monitoring of API Separator
influent and effluent FSUOD determined an average of 68 percent removal, far below the
DRBC's required 89.25 percent for process wastewater streams. Accordingly, a project to
determine the treatability of the API Separator effluent, and a project to reduce the API
Separator's hydraulic loading were undertaken. The latter project had as its basis an in-
plant water use survey which concluded that a reduction in process wastewater flow to the
API Separator could be accomplished by installation of a brine cooler; replacement of
barometric condensers with surface condensers; segregation of sanitary wastes from the
process wastewater stream; and further segregation of oily water and once through cooling
water streams. The results of this project are evidenced by a reduction in the hydraulic
loading from 3,750 to 1,700   gpm,
Treatability of the API Separator effluent was investigated through the operation of a
bench scale activated sludge unit and an extended aeration pilot plant. With accumulated
data as the basis, a preliminary biological treatment system design was prepared. The
proposed full scale design required intermediate facilities for oil removal, two 369,000
gallon aeration basins, final clarifiers, an anaerobic digester, and both biological and oily
sludge dewatering facilities.
230