Two-phase anaerobic digestion of unscreened dairy manure

Demirer, Göksel Niyazi
Chen, S
Concentrated animal feeding operations along with a corresponding absence of suitable manure disposal methods have been shown to cause significant environmental and public health problems, including odors and nutrient enrichment and pathogen contamination of surface and ground waters. Anaerobic digestion (AD) of manure can offer substantial benefits, both economic and intangible, to animal feeding operators and surrounding communities, such as on-site energy generation, production of stable, liquid fertilizer and high quality solid soil amendment, reduction in odors, and reduction in ground and surface water contaminations. The two-phase AD has several advantages over conventional one-phase processes, such as selection and enrichment of different bacteria in each phase, increased stability of the process, and higher organic loading rates (OLR) and shorter hydraulic retention times (HRT). Even though several aspects of two-phase configuration might be very significant for efficient AD of dairy manure, its application has been limited to screened dairy manure only. Therefore, this study investigated possible exploitation of the advantages of two-phase AD for unscreened dairy manure. The results indicated that the use of a two-phase reactor at a SRT/HRT of 10 days (2 days acidogenic and 8 days methanogenic) for AD of dairy manure resulted in 50 and 67% higher biogas production at OLRs of 5 and 6 g VS/L day, respectively, relative to a conventional one-phase configuration with SRT/HRT of 20 days. Furthermore, the phased configuration could tolerate an elevated OLR of 12.6 g VS/L day, which was not achievable with a conventional one-phase configuration.


Ammonia removal from anaerobically digested dairy manure by struvite precipitation
Uludag-Demirer, S; Demirer, Göksel Niyazi; Chen, S (Elsevier BV, 2005-12-01)
Ammonia is one of the most important contaminants impairing the quality of water resources. When this is considered along with the fact that the global demand for nitrogenous fertilizers is in constant rise, the need for recovery as well as removal of nitrogen is well justified. Crystallization of N and P in the form of struvite (MgNH4PO4 center dot 6H(2)O), which is a slow releasing and valuable fertilizer, is one possible technique for this purpose. This study investigated the removal of NR4+ through stru...
Effect of starvation on the adhesive properties of xenobiotic degrading bacteria
Sanin, SL; Sanin, Faika Dilek; Bryers, JD (Elsevier BV, 2003-01-31)
The purpose of this study was to observe the effects of different starvation conditions on the surface characteristics and adhesive properties of bacteria. Three pure culture xenobiotic degrading bacteria were used in this study: Pseudomonas sp. strain A, Pseudomonas sp. strain D and Rhodococcus corallinus strain 11. These microorganisms were selected for to their ability to degrade cyanuric acid, which is a derivative of s-Triazine, a common herbicide. These microorganisms were separately starved for carbo...
Influence of nickel (II) and chromium (VI) on the laboratory scale rotating biological contactor
Taseli, B. K.; Gökçay, Celal Ferdi; Gurol, A. (Springer Science and Business Media LLC, 2008-09-01)
High concentration of heavy metals is toxic for most microorganisms and cause strict damage in wastewater treatment operations and often a physico-chemical pretreatment prior to biological treatment is considered necessary. However, in this study it has been shown that biological systems can adapt to Ni (II) and Cr (VI) when their concentration is below 10 and 20 mg/L, respectively. The aim of this study was to evaluate the effect of Ni (II) and Cr (VI) on the lab-scale rotating biological contactor process...
Molecular evaluation and antimicrobial susceptibility testing of Escherichia coli isolates from food products in Turkey
Kyere, Emmanuel Owusu; Bulut, Ece; AVŞAROĞLU ERKAN, MÜRŞİDE DİLEK; Soyer, Yeşim (Springer Science and Business Media LLC, 2015-06-01)
Some strains of Escherichia coli can be important food borne pathogens. Characterization and antimicrobial resistance testing of 28 E. coli isolates from random food samples obtained in Van, Turkey were performed. Primers for 6 indicator genes (fliC, stx1, stx2, eae, hlyA, and rfbE) for shiga toxin-producing E. coli and 5 indicator genes for each pathogroup (bfpA, aggR, ipaH, daaD, st, and lt) were used. E. coli isolates were also typed using pulsed field gel electrophoresis with the XbaI restriction enzyme...
Anaerobic treatment of olive mill wastes in batch reactors
Bayramoğlu, Tuba Hande; DEMİRER, GÖKSEL NİYAZİ (Elsevier BV, 2000-01-01)
Anaerobic treatment of olive oil mill wastes, namely black water and prina, was investigated in batch reactors. Biochemical methane potential (BMP) tests were conducted to determine the anaerobic biodegradability of black water and/or prina. With these BMP tests the biodegradability of olive mill wastes (OMWs) at different initial chemical oxygen demand (COD) concentrations and corresponding methane gas productions were investigated. Furthermore, a screening study was performed to determine the most importa...
Citation Formats
G. N. Demirer and S. Chen, “Two-phase anaerobic digestion of unscreened dairy manure,” PROCESS BIOCHEMISTRY, pp. 3542–3549, 2005, Accessed: 00, 2020. [Online]. Available: