Alkaline solubilization and microwave irradiation as a combined sludge disintegration and minimization method

Date

2009-5

Author

Doğan, Ilgın
Sanin, Faika Dilek

Metadata

Show full item record

Item Usage Stats

204
views

0
downloads

Commonly used pretreatment method of alkaline solubilization (using NaOH) and a relatively new technology of microwave (MW) irradiation (160 degrees C) were combined as a pretreatment method of waste activated sludge (WAS) in this study. First alkaline and MW pretreatment methods were examined separately, then their combination for different conditions was investigated in terms of their effect on COD solubilization, turbidity and capillary suction time (CST). For combined pretreatments, soluble COD to total COD ratio (SCOD/TCOD) of WAS increased from 0.005 (control) to 0.18, 0.27, 0.34 and 0.37 for combined methods of MW and pH-10, 11, 12 and 12.5, respectively. Deteriorated dewaterability due to alkaline pretreatment was also improved due to the incorporation of MW irradiation. Further, with small scale batch anaerobic reactors, pH-10, pH-12, MW (alone), MW+pH-10 and MW+pH-12 pretreated WAS samples were anaerobically digested. Highest total gas and methane productions were achieved with MW + pH-12 pretreatment with 16.3% and 18.9% improvements over control reactor, respectively. Finally the performance of MW+pH-12 pretreatment was examined with 2L anaerobic semi-continuous reactors for 92 days and compared to that of the control reactors. These reactors were operated at an SRT of 15 days. After steady state, 43.5% and 55% improvements were obtained in respective daily total gas and methane productions. TS, VS and TCOD reductions were improved by 24.9%, 35.4% and 30.3%, respectively based on a relative calculation with respect to control reactors. This way combined alkaline-microwave treatment proved to be an effective sludge minimization method. Pretreated digested sludge had 22% improved dewaterability than unpretreated digested sludge. Higher SCOD and NH3-N concentrations were measured in the pretreated digested sludge supernatant; however, PO4-P concentration did not increase much.

Subject Keywords

Alkaline pretreatment, Biogas, Dewaterability, Microwave pretreatment, Sludge minimization

URI

https://hdl.handle.net/11511/28579

Journal

Water Research

DOI

https://doi.org/10.1016/j.watres.2009.02.023

Collections

Department of Environmental Engineering, Article

Suggestions

OpenMETU
Core

Alkali activation of a slag at ambient and elevated temperatures Altan, Ekin; Erdoğan, Sinan Turhan (2012-02-01) Strength development of alkali activated slag (AAS) mortars, activated using alkali hydroxide and sodium silicate, was investigated at room and elevated temperatures. Heat evolution at room temperature was measured using isothermal calorimetry. Important differences were observed between critical activation parameters. Heat cured specimens gain strength rapidly, humid oven conditions being favorable, but given sufficient time room temperature curing yields comparable strengths. Both activators are needed fo...
Hydrogen production over molybdenum loaded mesoporous carbon catalysts in microwave heated reactor system Guler, Melih; Doğu, Timur; VARIŞLI, DİLEK (2017-12-15) Ammonia decomposition reaction to produce COx free hydrogen over molybdenum incorporated mesoporous carbon based catalysts was studied in a microwave heated reactor system. Mesoporous carbon is acting as the catalyst support as well as the microwave receptor in the reaction medium. While the highest conversion value was 49% in conventionally heated reaction system at 600 degrees C, total conversion value was achieved over the same catalyst at 400 degrees C in microwave heated system with a GHSV of 36,000 ml...
Microwave-Assisted Extraction of Phenolic Compounds from Caper DURMAZ, Ezgi; Şümnü, Servet Gülüm; Şahin, Serpil (2015-09-02) In this study, it was aimed to extract phenolic compounds from caper by using microwave and to compare the results with conventional extraction. For microwave-assisted extraction, power, extraction time, solid to solvent ratio, and solvent type were selected as independent variables. Dependent variables were total phenolic content (TPC), antioxidant activity, and concentration of phenolic compounds. The increase in solvent amount increased TPC. The highest TPC was obtained by using extraction conditions of ...
Organic acid production from the organic fraction of municipal solid waste in leaching bed reactors Doğan, Evrim; Demirer, Göksel Niyazi; Department of Environmental Engineering (2006) This study was carried out to evaluate the potential of high-rate anaerobic digestion of high-solids organic fraction of municipal solid waste (OFMSW) for the production of organic acids and alcohols in leaching bed reactors (LBRs). For this purpose, two different experimental set-ups, namely Set-1 and Set-2, were operated. In the Set-1, only OFMSW without paper was studied in two identical LBRs, whereas, four identical LBRs, fed with OFMSW with paper and cow manure in different proportions, were operated i...
High hydrostatic pressure assisted extraction of pectin from sugar beet pulp Kaya, Burcu; Okur, İlhami; Alpas, Hami; Oztop, Mecit Halil (2021-05-01) This study aimed to investigate the effect of high hydrostatic pressure assisted extraction (HHPE) (250, 350 and 450 MPa at 40 degrees C for 5 min with/without acid addition) of pectin from sugar beet pulp and compare its properties with pectin obtained from conventional extraction (CE). Degree of esterification (DE), galacturonic acid (Gal-A) content, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) relaxometry experiments were performed on the obtained pectin powder. HHP...

Citation Formats

I. Doğan and F. D. Sanin, “Alkaline solubilization and microwave irradiation as a combined sludge disintegration and minimization method,” Water Research, pp. 2139–2148, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/28579.