45    ANAEROBIC PROTOCOL FOR ASSESSING
INDUSTRIAL WASTE TREATABILITY
James C. Young, Kappe Professor of Environmental Engineering
Nadim Reza Khandaker, Graduate Research Assistant
Department of Civil and Environmental Engineering
The Pennsylvania State University
University Park, Pennsylvania 16802
INTRODUCTION
Recent promulgation of strict standards for industrial waste pretreatment has greatly increased
the number of wastewaters that are candidates for anaerobic treatment. The challenge with industrial wastes is to determine the potential for anaerobic biodegradation prior to investing large
amounts of time and expense in design and field investigation. Various methods have been used
to assess the treatability of industrial wastewaters, but the methodology has varied significantly.1-5 In response to the need for a consistent procedure for determining the treatability-of
different industrial wastewaters by anaerobic processes, Young6 developed an anaerobic treatability screening protocol. The purpose of this paper is to describe the protocol and to report a
number of case studies in which the test protocol was used to determine the feasibility of using
anaerobic processes for treating specific industrial wastes. Specific examples include food processing wastes, chemical production wastes, petroleum wastes, and landfill leachate. Treatability
was based on assessment of the rate and extent of biodegradation, identification of the presence
of toxic substances, and dilution effects.
TESTING PROTOCOL
The treatability protocol consists of two test phases. Phase I is based on batch serum bottle
tests while Phase II involves the use of semi-continuous bench scale reactors. Master Culture Reactors (MCRs) are used to provide seed cultures having identifiable and repeatable characteristics so that measurements made at different times and with different wastes have a common microbial and biochemical basis.6 These MCRs typically are maintained in 8 to 12-L glass vessels
and are operated under the following conditions:
1. A feedstock of 20,000 mg/L ethanol COD in Nutrient/Mineral/Buffer (NMB)
medium,
2. A temperature of 35°C,
3. Hydraulic and solids retention times of 20 days,
4. A COD loading rate of 1.0 g/L-d.
The reactors are fed one time per day using a draw and fill procedure. Other HRT/SRT/load-
ing/feeding combinations may be used for specific wastes without compromising the structure of
the protocol as long as the basic elements of culture control are maintained. Cultures can be
transferred from full-scale anaerobic reactors, but in this case the concentration of active microorganisms is unknown. Gas production is measured daily and the biomass concentration is
monitored at 7 to 10-day intervals.
Nutrient/Mineral/Buffer Medium
Formulations of stock solutions for the NMB used in this study are given in Table I. Nutrient/Mineral/Buffer solutions consist of 10 mL each of Mineral Base I, Mineral Base II, Nutrient
50th Purdue Industrial Waste Conference Proceedings, 1995, Ann Arbor Press, Inc.. Chelsea, Michigan 48118.
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