United States Environmental Protection Agency EPA/540/F-96/505 May 1996 &EPA SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION Emerging Technology Bulletin Innovative Methods for Bioslurry Treatment IT Corporation Technology Description: Slurry biodegradation systems are cre- ated by combining soil or sludge with water. This technology provides rapid biodegradation, due to enhanced mass transfer rates and increased contaminant to microorganism contact. After appropriate pretreatment, the contaminants are suspended in a slurry form and mixed in a tank. Aeration is provided by spargers. Mixing is provided by aeration alone or by aeration and mechani- cal mixing. Nutrients and neutralizing agents are supplied to relieve any chemical limitations to microbial activity. Other materi- als can be used to support growth and induce degradation of contaminants, or increase substrate availability to degradation. Manual B-1 An increased rate and extent of polycyclic aromatic hydrocarbons (PAH) biodegradation in slurry reactors has been developed. Two 60 liters (L) TEKNO Associates bioslurry reactors and a 10-L fermentation unit in semi-continuous, plug-flow mode, were operated for a 6-month period. The first 60-L reactor received fresh feed daily and supplements of salicylate and succinate to enhance PAH biodegradation. A schematic flow diagram of this bioslurry treatment is shown in Figure 1. Effluent from the first reactor is fed to the second 10-L reactor in series, where Fenton's reagent (Fe++ + H2O2 is added to accelerate oxidation of 4- to 6- ring PAHs. The Third reactor in series, biologically oxidizes re- Atmosphere Effluent Process Water (Manual Transferring) Make-Up Process -- Water Effluent Legend (§3) Sample Port (PR) Pressure Regulator I PI) Pressure Indicator (KE) Timer M-1 Feed Mixer T-1 Feed Container (20L) B-1 Air Blower P-1 Feed Pump (12L/Day) R-1 Air Rotameter S-1 Air Filter M-2A,B,C Bioreactor Mixer T-6 Bio Reactor 1 (60L) T-7 Bio Reactor 2 (60L) T-8 Bio Reactor 3 (10L) Z-1 Carbon Adsorption P-6 Slurry Pump P-5 Effluent Pump T-2 Clarifier Z-2 Air Sampling Device T-5 Effluent Container (20L) Figure 1. Schematic diagram of bioslurry treatment. (Source: IT Corp., 1995) Printed on Recycled Paper ------- maining contaminants, after being treated with Fenton's reagent. R3 received no additions ofsalicylate and succinate. The reactor was aerated, nutrient-amended, andpH adjusted only. Waste Applicability: Biosltuy reactors have the potential to treat a wide range of organic contaminants such as pesticides, fuels, creosote, pentachlorophenol (PCP), and somehaloge- nated volatile organicsitis expected to treat coal tars, refinery wastes, hydrocarbons, wood-preserving wastes, and organic and chlorinated sludges. The pressure of heavy metals and chlorides may inhibit the microbial metabolism and require pretreatment. These units have demonstrated biodegradation of selected con- taminant concentrations ranging from 2,500 to 250,000 milli- grams/kilograms (mg/kg). Test Results: Blended slurry PAH and CPAH maximum concen- trations were 6,120 and 434 mg/kg, respectively. The bioslurry reactor system demonstrated up to 95% and 84% transformation of PAH and CPAH, respectively. During optimal operation, the influent PAH concentration was decreased from 6,210 mg/kg to 325 mglkg. Influent CPAH concentrations were decreased from 422 mglkg to 65 mglkg. Total heterophobic counts in Rl and R3 ranged from 108 to 109 colony forming unit per milliliter (CPU/ ml). Despite severe conditions maintained inR2, total microbial counts ranged up to 104 CFU/mL. For Further Information: EPA Project Manager Brunilda Davila U.S. Environmental Protection Agency National Risk Management Research Laboratory 26 West Martin Luther King Drive Cincinnati, OH 45268 (513) 569.7849 FAX: (513) 569-7879 Technology Developer Contact: Randi Brown IT International Technology Corporation 1425 South Victoria Court Suite A San Bernadino. CA 92408-292 Phone: 909-799-6869 Fax: 909-799-7604 United States Environmental Protection Agency Center for Environmental Research Information Cincinnati, OH 45268 Official Business Penalty for Private Use $300 BULK RATE POSTAGES FEES PAID EPA PERM IT No. G-35 EPA/540/F-96/505 ------- |