Development of Waste Oil Recovery
Processes at Armco Steel Corporation
VERLIN W. FOLTZ, Supervising Research Chemist
Research and Technology
Armco Steel Corporation
Middletown, Ohio
INTRODUCTION
One of the major pollution control problems in the steel industry today is the
disposal of waste oil. Waste oil may originate from a number of sources; the loss of
surplus coating oils, the discarding of spent rolling lubricants, and leaking hydraulic
systems are excellent examples. Armco's facility in Middletown, Ohio, may generate
several thousands of gal of waste oil/day.
If the oily wastes were not intercepted, most of the waste oil would find its
way to the nearby Great Miami River. If the oily wastes were simply intercepted,
hauled to the dump, and burned, an air pollution problem would obviously result;
this procedure is also unsuitable because of the hauling costs involved and the risk of
ground water contamination. Incineration of all waste oil 'would be quite costly.
Disposal through a contract hauler has not been a very satisfactory approach.
The only acceptable solution to the waste oil problem is a waste treatment
program. Armco has such a program, and close team work among research,
engineering, and operating personnel has made the effort successful. Air and water
pollution due to oily wastes are being reduced to the minimum technically possible,
waste oil is being recovered for reuse wherever feasible, and waste treatment costs are
being minimized.
This paper is limited to describing the development of economical processes for
reclaiming oil from waste streams which contain relatively high concentrations of oil
(one per cent or more). Processes for treating more dilute oily wastes will be reported
later.
The processes described below have only recently become possible; they all
depend to some degree on the use of a new class of chemicals now available to the
waste treatment chemist. These chemicals are organic polymers, known variously as
polyelectrolytes, coagulant aids, emulsion breaking chemicals, etc. Many are effective
in oil recovery processes.
WATER CONTAMINATED WITH OIL AND SOLIDS
Problem
The scale-breaking and welding equipment ahead of three strip-pickling lines
leak appreciable amounts of hydraulic fluid, which in this case is mineral oil. The
equipment design is such that the hydraulic seals are very difficult to replace; when
seals are replaced, the leakage problem soon recurs. The hydraulic oil leakage
becomes mixed with the waste water discharged from this area. The waste stream
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