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The Effect of Nickel on Thermophilic Bacteria for Wastewater Treatment Doanh Van, PhD., PE., CEM •Associate Professor & Chair Engineering Elsie Y. Smith •Associate Professor of Biology Midsouth Annual Engineering & Science Conference (May 11, 2005) Christian Brothers University The Wastewater of Interest Sewage (sea ward) Any water that’s not useful. • Residences and businesses. • Process water discharged from manufacturing plants. Typical Analysis of Domestic Wastewater Solids BOD5 COD TOC N P Chlorides Sulfates Alkalinity Grease Total coliform VOC 720 mg/L 220 mg/L 500 mg/L 160 mg/L 40 mg/L 8 mg/L 50 mg/L 30 mg/L 100 mg/L 100 mg/L 10 -100 million/100 mL 250 ppb Typical Analysis of Industrial Wastewater COD 5,600 - 16,200 mg/L BOD5 3,350 - 4,625 mg/L TSS 160 - 340 mg/L pH 6.1 - 8.1 Another Analysis of Industrial Wastewater COD BOD5 TSS pH 8,400 - 38,800 mg/L 5,250 - 24,250 mg/L 180 - 670 mg/L 3.5 - 5.4 Wastewater Treatment The removal of organic matters, solids, nutrients, disease-causing organisms and other pollutants from wastewater before readmitting it to the receiving water body or discharging it to the POTWs. The Governing Law CWA or Clean Water Act (1987) aka FWPCA (1972) • Goal: to restore and maintain the chemical, physical and biological integrity of the nation’s waters • Objectives: provide for propagation and protection of fish, shellfish, and wildlife and recreation. Also to eliminate the discharge of pollutants (zero discharge) The Science of Wastewater Treatment bacteria CHONS + O2 --------------->> CO2 + H2O + NH3 + Others organic pollutants Gravity causes separation of solid phase from liquid The Use of Bacteria Psychrophilic (~13°C ) Mesophilic (~32°C ) Thermophilic (higher range of T) • • • • • High strength (BOD5, COD) wastewater Explosive laden wastewater Rapid biodegradation Low growth yields Self-sustained process About Thermophiles Bacteria with special enzymes (extremozymes) • String of amino acids fold themselves very tightly. • Have less amino acid glycine in the structure. • Have chaperonin protein for bio maintenance 110° C bacterial growth has been reported 250° C also reported-- questionable. (Atlas & Mosby). Wastewater Treatment Technologies Secondary Treatment aka Biological Treatment • Activated Sludge process • Trickling Filter process • Sequential Batch Reactor process The Challenges in Treating Certain Industrial Wastewater Stream: High strength Potentially toxic organics • Dissolved • Suspended One Highly Effective Process High Strength Waste Stream Equalization Tank Thermophilic Biological Reactor Eff Ultrafiltration Recycle Sludge Chemical Sludge Treatment http://www.pmcbiotec.com/downloads/Thermophilic_wastewater.pdf#search='thermophilic%20wastewater%20treatment‘ A Pilot Scale Was Conducted •1000-gallon SS reactor. •Agitated. •Insulated. •Recirculation loop also included a 0.02-micron ultrafiltration at 132 m3/d. The Results Temperature (degree C) Thermophilic Reactor Acclimation Time 60 50 40 30 20 10 0 0 5 10 15 20 Time (days) 25 30 35 Temperature (degree C) Steady State Thermophilic Reactor Operation 60 50 40 30 20 10 0 30 32 34 36 Time (days) 38 40 Reactor OUR vs Reactor Temperature OUR (mg/l-h) 50 40 30 20 10 0 -10 25 30 35 40 45 Reactor Temperature (C) 50 55 60 Time (days) Feed Concentration Efficiency 79 73 67 61 55 49 43 37 31 25 19 13 COD Removal Efficiency (%) 100.00 80.00 60.00 40.00 20.00 0.00 7 250000 200000 150000 100000 50000 0 1 Feed Concentration (mg/L) Feed Strength and COD Removal Efficiency The Unexpected Problem Temperature (degree C) 60 50 40 30 20 10 0 75 80 85 90 95 100 105 110 115 time (days) 120 125 130 135 140 Total Heavy Metals 110 mg/L Nickel 93.5 Cadmium <0.01 Chromium 1.8 Lead 0.4 Zinc 13 Mercury 0.002 Silver <0.01 Copper 0.43 Arsenic 0.002 Lessons Learned Thermophilic bacteria for wastewater treatment technology is innovative. Highly effective for organic wastestream. Some inorganic contents in the feed stream are very undesirable. Nickel is fatal to thermophilic bacteria. • It can alter cell’s membrane properties and influences oxidation/reduction systems. • It failed the process. References “Microorganisms in Our World”, Ronald M. Atlas, Mosby, 1995, pp. 299-300. http://www.microbe.org/microbes/thermophiles.asp http://www.jbc.org/cgi/content/abstract/276/20/16731 http://www.eagle-min.com/faq/faq101.htm http://www.pmcbiotec.com/downloads/Thermophilic_wastewater.pdf#search='thermophilic %20wastewater%20treatment‘ http://p2library.nfesc.navy.mil/P2_Opportunity_Handbook/9-II-9.html http://ce.ecn.purdue.edu/~piwc/w3-research/lapara/lapara-research.html http://www.cecl.com.tw/en_docs/scope/waste/tab/tab-e.htm http://www.iwaponline.com/wst/04001/wst040010053.htm http://profiles.nlm.nih.gov/KK/B/B/G/C/_/kkbbgc.pdf