Page 176 - Environmental Control in Petroleum Engineering

162 Environmental Control in Petroleum Engineering

to the vendor for refilling. Oily rags can be cleaned and reused. Used
drilling mud can also be used to make cement. Waste acids can be
used to neutralize caustic wastes, and vice versa.
Many wastes can be used as feedstock by other companies. Mate-
rials exchanges are available in numerous locations to assist companies
in finding other companies that may be interested in obtaining wastes.
These exchanges should be contacted to see exactly what materials
can be recycled in each area. Care should be taken, however, that the
recycler is reputable and in compliance with all regulations. Transfer
of a waste to a waste exchange does not necessarily relieve the waste
generator of future liability for what the waste exchange does with
the waste. A list of some of the major waste exchanges in the United
States is given in Appendix C (Quan, 1989).
In some cases, only part of a particular waste stream contains
valuable materials that can be reused. It may be possible to recover
or reclaim the valuable materials, reducing the net volume of waste.
For example, crude oil tank bottoms, oily sludges, and emulsions can
be treated to recover their hydrocarbons. Oily materials can also be
burned for their energy content. Gravel and cuttings can be washed
and used in construction of roads and other sites.
Companies can take proactive action to assist employees in finding
suitable opportunities for recycling. For example, funds generated from
recycling can be placed in an employee fund for use at employee
discretion to encourage recycling. Emphasis can also be placed on
purchasing recycled goods to increase the market for them.

5.3.3 Treatment and Disposal

Wastes that cannot be eliminated must be treated and disposed.
Treatment is used to reduce the volume and/or toxicity of wastes
and/or put it in a form suitable for final disposal. A number of
treatment and disposal options are available for the wastes generated
in the petroleum industry. These options are discussed in Chapters 6
and 7, respectively.

5.4 CERTIFICATION OF DISPOSAL PROCESSES

One option for waste management is to ship wastes to an off-site,
commercial waste disposal facility. Paying a disposal facility to take