Biological Reduction of
Phenolic Type Industrial Waste
W. R. HORNE, Staff Engineer
General Services Department
J. E. HURSE, Senior Process Chemist
Metallurgical and QuaUty Control Division
Lone Star Steel Company
Lone Star, Texas
Over the past several years a co-ordinated study has been made by several
departments at Lone Star Steel Company to determine the most desirable and
economical method to dispose of the coke plant ammonia still waste liquor involving approximately 50,000 gals per 24hrs.
The most objectional materials in the coke plant ammonia still waste liquor
are the phenolic type compounds along with traces of cyanides. Since this effluent discharges into a reservoir that is a source of domestic water for surrounding municipalities and also recreational facilities, it was felt that the previous
method of lagoons or oxidation ponds with dilution was not completely adequate.
Also, the phenols liberate objectional taste and odors, especially when chlorinated.
Careful consideration was given to various possible methods of disposal of
this waste some of these including the reason for their rejection were-.
1. Reduction by evaporation in the coke quenching tower. This was not
practical because the waste would be discharged into the atmosphere as steam.
As condensation occurred it would again fall out causing a serious corrosion problem for everything metallic in the area.
2. Reduction by a chemical method. This was not ideal due to the quantities of chemicals required.    The cost of the chemicals prohibited this method.
3. Reduction by pumping into some sub-surface strata similar to salt water
disposal. This method was rejected due to sludges or tarry acids in the water
which would in all probability clog the pumps, piping, and the sub-surface strata
itself.
4. Reduction by a dephenolizing tower. The initial cost of this equipment
was prohibitive along with the lack of demand for the finished product. Also, in
the quantities available it was impractical to produce this product from a profit
and loss standpoint.
At this time the biological oxidation method was considered. By pilot plant
studies was proven to be a satisfactory method. The term "biological oxidation"
is a bio-oxidation process as compared to lagoons or oxidation ponds. The advantages of this method compared to the methods considered previously were
(1) low initial cost of installation, (2) low cost of operation, and (3) the little attention that this process required while still producing an effluent low in phenols.
As a result of the previously mentioned pilot plant studies and laboratory test
work, the following conclusions were made:
1. The discharge from the ammonia still must be segregated from the bal-
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