Page 186 - Environmental Control in Petroleum Engineering

CHAPTER 6

Waste Treatment

Methods

During drilling and production activities, many wastes are generated
that must be treated. The purpose of waste treatment is to lower the
potential hazards associated with a waste by reducing its toxicity,
minimizing its volume, and/or altering its state so that it is suitable for a
particular disposal option. For many wastes, treatment is required prior
to final disposal. A variety of treatment methods are available for most
wastes, but not all methods can be used on all waste streams. The
different treatment methods vary considerably in effectiveness and cost.
Most waste treatment processes involve separating a waste stream
into its individual components, e.g., removing dissolved or suspended
hydrocarbons and solids from water or removing hydrocarbons from
solids. In many cases, a series of methods may be needed to obtain
the desired treatment levels (Schmidt and Jaeger, 1990).
This chapter describes a variety of processes to treat water and
solids for subsequent reuse or disposal. It also describes treatment
processes for various air pollutants. More detailed discussions of
treatment and disposal methods are available in the literature (Freeman,
1989; Tchobanoglous and Burton, 1991; Canadian Petroleum Associa-
tion, 1990; Jones and Leuterman, 1990; Wojtanowicz, 1993).

6.1 TREATMENT OF WATER

A number of methods are available to treat contaminated water to
prepare it for reuse or disposal. The contaminants in water most
commonly encountered in the petroleum industry can be grouped into
two broad categories: hydrocarbons and solids. These contaminants can
be either suspended or dissolved as discussed below.

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