32    HEAVY HYDROCARBON RECOVERY
Michael L. Braden, Senior Research Chemist
Nalco Chemical Company
Sugar Land, Texas 77487
Michael D. Backode, Product Specialist
Nalco Chemical Company
Naperville, Illinois 60563
William Dimoplon, Senior Project Manager
Bird Environmental
Spring, Texas 77373
INTRODUCTION
This paper is presented in two parts. Part A describes the overall project and focuses on the work of
Bird Environmental relating to the pitch mining and processing operations. Part B presents the
contribution of Nalco Chemical Company in developing an effective chemical treatment for de-
emulsification and solids flocculation to purify the recovered waste stream.
Part A. Hydrocarbon Recovery from an Oil Refinery Pitch Pit —Pitch Mining and Processing
BACKGROUND
Bird Environmental is presently recovering heavy hydrocarbons from a pitch storage pit for a major
U. S. petroleum refinery located in the Southwest. The refinery processes approximately 200,000
barrels per day of crude oil and natural gas condensates. Refinery units include crude distillation,
catalytic reforming, catalytic cracking, distillate hydrotreating, and residual hydrocracking.
The pitch pit originally contained approximately 280,000 barrels of solidified residual fuel oil
(vacuum tower bottoms) and covered approximately three to four acres of land. This and several
other pitch pits on the site were formed during World War II as a result of Ihe urgent need to supply
distillate fuels to support the war effort and to supply domestic needs during that critical period.
The refinery produced more residual fuel oil (vacuum tower bottoms) than could be sold at that
time. Modern residual hydrocracking technology, now used to convert residual oils into distillate
fuels, had not yet been commercialized; consequently, excess residual oil was routed to the storage
pit.
INCENTIVES FOR HYDROCARBON RECOVERY
Refinery management has taken a proactive stance on environmental matters. The cost of closing
the pitch storage pit will be largely offset by credit for the recovered oil, based on the current market
value of residual fuel oil.
The pitch is being mined and processed into a refinery feedstock at a cost which is below the current
market price of crude oil (approximately $20 per barrel). This stream is being economically converted
into distillate fuels. By comparison, other options, such as blending to produce No. 6 fuel oil, asphalt
or cement kiln fuel are considered less economically attractive.
By pursuing its aggressive resource recovery program, refinery management is now well positioned
to achieve potentially more favorable economics for the remaining on-site pits. Processing costs for
Ihe hydrocarbon recovery from the remaining pits will be significantly reduced based on economics
from utilizing the existing processing system after the current project has been completed.
47ih Purdue Industrial Waste Conference Proceedings,  1992 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Printed in U.S.A.
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