Energy production from yard wastes via one-stage and two-stage anaerobic digestion and investigation of pretreatment effect

Download

index.pdf

Date

2020

Author

Kalaycıoğlu, Nihan Nur

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

298
views

106
downloads

Energy production from lignocellulosic biomass is receiving ever-increasing interest. This thesis study investigated the energy production from yard wastes, which is an abundant lignocellulosic substrate, via one-stage anaerobic digestion (OSAD) and two-stage anaerobic digestion (TSAD) of yard waste. The effect of pretreatment options (alkaline (AP), thermal (TP) and ultrasound (UP)) and initial solids concentration (2%, 5% and 8% total solids, TS) on hydrogen and methane production yields in OSAD and TSAD were researched. Solubility increase was obtained via AP, TP and UP by 43%, 51% and 17%, respectively. OSAD batch experiments showed that the highest CH4 yield was obtained with AP-yard waste at 5% TS as 313 mL CH4/g VS. AP was the best pretreatment option among others for all three TS% options studied in terms of CH4 yields. Considering the TSAD experiments, the highest H2 yield was obtained with AP-yard waste at 2% TS ( 30.5 mL H2/g VS) in dark fermentation stage. AP was found again as the best pretreatment option for all TS contents studied in terms of H2 yields. In methanogenesis stage of TSAD, the obtained yields were very low. The highest methane yield was obtained with TP-yard waste at 2% TS (40 mL CH4/g VS). TP-yard waste gained the highest methane yield in all three TS contents. OSAD of yard waste provided 11 MJ/kg VS energy recovery. Yet only 2 MJ/kg VS could be achieved via TSAD of yard waste. It can be concluded in this study that it is possible to achieve energy from yard wastes whether it is pretreated or not when initial TS content is 2%. For higher TS contents such as 5%, AP improves the energy yield. TSAD is not sufficient to apply for yard wastes even if it is pretreated with AP, TP and UP. This was mainly attributed to the potential inhibitory by-products produced after either pretreatments applied and/or dark fermentation.

Subject Keywords

Sewage, Sewage Purification, Sewage Purification Anaerobic treatment., Anaerobic digestion, dark fermentation, yard waste, pretreatment, solids concentration.

URI

http://etd.lib.metu.edu.tr/upload/12625353/index.pdf
https://hdl.handle.net/11511/45590

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Hydrogen production by different strains of Rhodobacter sphaeroides Gündüz, Ufuk; Yucel, M; Turker, L; Eroglu, L (2000-06-15) Utilisation of solar energy by photosynthetic microorganisms for H-2 production attracts much interest due to unlimited supply of energy. It is important to identify the most effective strain in terms of hydrogen production for the feasibility of the process. Four different strains of Rhodobacter sp. were grown in a water-jacketed cylindrical glass-column photobioreactor under anaerobic conditions. Growth characteristics and hydrogen production rates were determined. Comparison between strains of Rhodobacte...
Accessing unconventional biofuels via reactions far from local equilibrium Gao, Yu; Üner, Necip Berker; Thimsen, Elijah; Foston, Marcus B. (2018-08-01) The thermochemical production of fuels from lignocellulosic biomass is constrained by equilibrium thermodynamics. However, low temperature plasma reactions are not governed by local equilibrium and involve the formation of unique radical and ion species. Thus, low temperature plasma can open pathways in the conversion of lignocellulosic biomass to products not observed in conventional thermochemical processing. In this effort, a novel radio-frequency (RF) plasma-enhanced fluidized bed reactor was utilized f...
Solar energy potentials in strategically located cities in Nigeria: Review, resource assessment and PV system design Okoye, Chiemeka Onyeka; Taylan, Onur; Baker, Derek Keıth (2016-03-01) Ensuring energy security increasingly requires expanding both yield and resilience of supply through source diversification. In this study, the current energy situation of Nigeria is presented through a detailed literature review. The survey reveals that access to the national grid is limited, and the power delivered to areas classified as urban with grid connection is very unreliable. An initial assessment of the potential utilization of solar based technologies for electricity generation is presented for ...
Wastewater sludge in bioelectricity generation using microbial fuel cells Ömeroğlu, Seçil; Sanin, Faika Dilek; Department of Environmental Engineering (2019) Today, the majority of world’s energy is provided by fossil fuels which soon will be exploited. This pressure forces countries to investigate renewable energy technologies like microbial fuel cells (MFCs). MFCs can convert chemical energy in organic matter into electricity via microbial activity. The objective of this study was to investigate the operational parameters and interactions within the MFCs to overcome the challenges that limit their full scale applications. This study started with optimization e...
Energy consumption and GDP: causality relationship in G-7 countries and emerging markets Soytaş, Uğur; Sarı, Ramazan (2003-01-01) The causality relationship between energy consumption and income is a well-studied topic in energy economics. This paper studies the time series properties of energy consumption and GDP and reexamines the causality relationship between the two series in the top 10 emerging markets-excluding China due to lack of data-and G-7 countries. We discover bi-directional causality in Argentina, causality running from GDP to energy consumption in Italy and Korea, and from energy consumption to GDP in Turkey, France, G...

Citation Formats

N. N. Kalaycıoğlu, “Energy production from yard wastes via one-stage and two-stage anaerobic digestion and investigation of pretreatment effect,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Environmental Engineering., Middle East Technical University, 2020.