As fields and developments move into the more mature phases of
development the production of increasing volumes of produced water is often the
result. This, together with more stringent international environmental discharge
legislation, and an increasing trend towards produced water re-injection, means
that operators are increasingly obliged to treat produced water to higher
standards prior to disposal or reuse.
The composition of produced waters is often very complex and
many of the components are toxic and detrimental to the environment at large. It
is essential that such components can be identified and quantified so that their
environmental impact can be correctly assessed.
Produced waters can contain a whole cocktail of undesirable
chemicals and agents the most frequently encountered being:
Poly Aromatic hydrocarbons
Benzene, Toluene, Ethyl Benzene and Xylene
Heavy metals such as arsenic, lead, mercury and cadmium
Production chemicals, scale / corrosion inhibitors,
demulsifiers, and residual biocides.
Discharge of any or all of these to the environment is becoming
increasing more difficult (for obvious reasons) as greater emphasis is place on
environmental issues by all parties involved in the oil industry.
Re-injection of produced waters can have clear economic and
ecological advantages over surface disposal. This is based on the premise
that if the produced water has to be treated to a high degree for surface
disposal, then an operator might as well re-inject it for pressure maintenance
or simply disposal.
Whether the produced water is to be treated for surface
disposal or re-injection a full and thorough understanding, of both the chemical
and physical properties of that water are essential for any successful treatment
design, in terms of minimising the effects of dissolved or dispersed
contaminants on water quality.
In addition to the environmental concerns of deliberate
discharge of produced water, there is always the ever present danger of
accidental release of hydrocarbon and aqueous fluids into the environment.
Produced waters are often hot, saline and very corrosive, and hence very
aggressive towards carbon steel materials.
Oil Plus has the expertise and specialist analytical equipment
to fully characterise any produced water,
and has a well established worldwide track record in produced water analysis and produced water treatment system