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Moisture-Induced Pattern of Gases and Physicochemical Indices in Corn Straw and Cow Manure Composting. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11188493] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study investigated the altering effect of moisture on the emission pattern of gases and the evolutionary dynamics of physicochemical indices in corn straw and cow manure composting. Exploring this effect was reasonable to unravel the use of moisture as a cheap alternative to control gaseous emissions and improve the final properties of compost. The nutrient dynamics of the compost showed 21.6% losses in total organic carbon content, with a 33.3% increase in total nitrogen content at the end of composting. All the gases (CH4, CO2, N2O and NH3) yielded a common emission pattern despite the differences in moisture content. Except for CH4, the peak and stable emission periods of all the gases were observed on the 5th day (thermophilic phase) and after the 27th day (late mesophilic phase) of composting, respectively. Emission reductions of 89%, 91%, 95% and 100% were recorded for CH4, CO2, N2O and NH3, respectively, during the late mesophilic phase of composting. From the study, the 65% moisture content was efficient in reducing the loss rate of the gasses and nutrient contents of the compost. This study would enable farmers to channel organic residues generated into compost while minimizing pollution and nutrient losses associated with the composting process.
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2
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Li MX, He XS, Tang J, Li X, Zhao R, Tao YQ, Wang C, Qiu ZP. Influence of moisture content on chicken manure stabilization during microbial agent-enhanced composting. CHEMOSPHERE 2021; 264:128549. [PMID: 33065328 DOI: 10.1016/j.chemosphere.2020.128549] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/24/2020] [Accepted: 10/03/2020] [Indexed: 06/11/2023]
Abstract
Moisture content (MC) influences substance transformation during composting and the function of exogenous microbial agents. Unsuitable MC could cause leaching, nutrient loss, and secondary contamination. In this study, chicken manure composting with varied MC (45-61%) was conducted under functional microbial agent inoculation to explore the optimum condition for composting and the potential mechanism. Due to the enhanced decomposing, nitrosation, and nitrification effect lead by the functional microorganism, treatment with the optimal MC (53%) exhibited the highest composting temperature (61 °C) and longest high-temperature period (15 days), achieving a final carbon-nitrogen ratio (C/N), humic acids and fulvic acids ratio (HA/FA), and NH4+-N/NO3--N at 19.20, 2.00, and 0.93, respectively. After composting, the total nitrogen (TN) increased by 13.01-22.10% in the treatments with microbial agent inoculation compared with original stack, while it decreased by 7.76% in control. The highest nutrient (5.63%, 5.63-14.20% higher than the other composts) and better product safety (11.43-23.58% higher seed germination than others) were observed in treatment with MC at 53%, exceeding the Chinese national standard for organic fertilizer. Obviously, under optimum MC, microbial agent augmentation lead to high quality and safe compost products after a short composting period (25 days) without any leaching, which suggested an efficient way to promote the recycling and recovery of husbandry waste.
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Affiliation(s)
- Ming-Xing Li
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - Xiao-Song He
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Jian Tang
- School of Civil Engineering, Sichuan University of Science and Engineering, Zigong, 643000, China
| | - Xing Li
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - Rui Zhao
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - Yi-Qian Tao
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China
| | - Can Wang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China.
| | - Zhong-Ping Qiu
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, China.
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Yuan J, Zhang D, Ma R, Wang G, Li Y, Li S, Tang H, Zhang B, Li D, Li G. Effects of inoculation amount and application method on the biodrying performance of municipal solid waste and the odor emissions produced. WASTE MANAGEMENT (NEW YORK, N.Y.) 2019; 93:91-99. [PMID: 31235061 DOI: 10.1016/j.wasman.2019.05.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 04/15/2019] [Accepted: 05/18/2019] [Indexed: 06/09/2023]
Abstract
The effects of inoculation amount and application method on the biodrying of municipal solid waste (MSW) was investigated in this study. Results showed that a low level (5%) of inoculation with mature compost significantly improved the biodrying index (4.96), while adding greater amounts decreased the biodrying performance by increasing the volatile solid degradation rate. Covering the pile with inoculation material resulted in the highest water removal (72.7%) and greatest water content reduction (from 60.2% to 17.7%). Meanwhile, first covering and then incorporating the inoculation material into the biodrying pile did not improve biodrying performance. Clearly, addition of varying amounts of inoculation material via different application methods enhanced cellulose degradation rates by 2.3-14.2%. Using 10% inoculation material reduced the NH3 emissions by 39.1-54.3% regardless of inoculation method, inoculation amount had a greater effect on NH3 emissions than that of inoculation method. The covering inoculation material could reduce 65.08% H2S emission, the inoculation method had a greater effect on H2S emissions than that of inoculation amount. Given the comprehensive considerations of emission reduction and biodrying performance, a covering of 10% inoculating material is a suitable approach to improve biodrying performance and mitigate odorous gases emissions.
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Affiliation(s)
- Jing Yuan
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Difang Zhang
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Ruonan Ma
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Guoying Wang
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Yun Li
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Shuyan Li
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Huan Tang
- Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Bangxi Zhang
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China; Guizhou Institute of Soil and Fertilizer, Guiyang 550006, China
| | - Danyang Li
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Guoxue Li
- College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China.
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Yuan J, Li Y, Zhang H, Zhang D, Chadwick D, Li G, Wang G, Chi M, Yang F. Effects of adding bulking agents on the biodrying of kitchen waste and the odor emissions produced. J Environ Sci (China) 2018; 67:344-355. [PMID: 29778167 DOI: 10.1016/j.jes.2017.08.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 07/28/2017] [Accepted: 08/21/2017] [Indexed: 06/08/2023]
Abstract
The effects of adding a bulking agent on the performance and odor emissions (ammonia and eight sulfur-containing odorous compounds) when biodrying kitchen waste were investigated. Three treatments were considered: the addition of either cornstalks (CS) or wood peat (WP) to kitchen waste as a bulking agent before biodrying, and a control treatment (CK). The water-removal rates for CK, CS, and WP treatments were 0.35, 0.56, and 0.43kg/kg, respectively. Addition of bulking agents to kitchen waste produced less leachate, higher moisture-removal rates, and lower consumption of volatile solids. The CS treatment had the highest biodrying index (4.07), and those for the WP and CK treatments were 3.67 and 1.97, respectively. Adding cornstalks or wood peat decreased NH3 emissions by 55.8% and 71.7%, respectively. Total sulfur losses were 3.6%-21.6% after 21days biodrying, and H2S and Me2SS were the main (>95%) sulfur compounds released. The smallest amounts of sulfur-containing odorous compounds were emitted when cornstalks were added, and adding cornstalks and wood peat decreased total sulfur losses by 50.6%-64.8%.
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Affiliation(s)
- Jing Yuan
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Yun Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Hongyu Zhang
- Beijing Building Materials Academy of Science Research/State Key Laboratory of Solid Waste Reuse for Building Material, Beijing 100041, China
| | - Difang Zhang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | | | - Guoxue Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China.
| | - Guoying Wang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Menghao Chi
- College of Resources and Environmental Science, Jilin Agricultural University, Jilin 130118, China
| | - Fan Yang
- Beijing Municipal Research Institute of Environmental Protection, Beijing 100037, China
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Onwosi CO, Igbokwe VC, Odimba JN, Eke IE, Nwankwoala MO, Iroh IN, Ezeogu LI. Composting technology in waste stabilization: On the methods, challenges and future prospects. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 190:140-157. [PMID: 28040590 DOI: 10.1016/j.jenvman.2016.12.051] [Citation(s) in RCA: 213] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 12/18/2016] [Accepted: 12/20/2016] [Indexed: 05/22/2023]
Abstract
Composting technology has become invaluable in stabilization of municipal waste due to its environmental compatibility. In this review, different types of composting methods reportedly applied in waste management were explored. Further to that, the major factors such as temperature, pH, C/N ratio, moisture, particle size that have been considered relevant in the monitoring of the composting process were elucidated. Relevant strategies to improve and optimize process effectiveness were also addressed. However, during composting, some challenges such as leachate generation, gas emission and lack of uniformity in assessing maturity indices are imminent. Here in, these challenges were properly addressed and some strategies towards ameliorating them were proffered. Finally, we highlighted some recent technologies that could improve composting.
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Affiliation(s)
- Chukwudi O Onwosi
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria.
| | - Victor C Igbokwe
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
| | - Joyce N Odimba
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
| | - Ifeanyichukwu E Eke
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
| | - Mary O Nwankwoala
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
| | - Ikemdinachi N Iroh
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
| | - Lewis I Ezeogu
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria
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Simujide H, Aorigele C, Wang CJ, Zhang TH, Manda B. Evaluation of calcium cyanamide addition during co-composting of manure and maize straw in a forced-aeration static-pile system. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2016; 14:18. [PMID: 27800167 PMCID: PMC5080734 DOI: 10.1186/s40201-016-0258-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 10/03/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Composting is one of the most environmentally friendly treatments to inactivate pathogenic organisms or reduce them to acceptable levels. However, even under thermal conditions, some pathogenic organisms such as E. coli could exist for a long time in composting. Such great persistence may increase the possibility of outbreaks of these organisms and further increase the environmental load. Calcium cyanamide (CaCN2) has recently been recognized to have the fungicidal effect on the pathogens of the soilborne diseases. So, the present study determined the effect of CaCN2 addition on composting progress as an antimicrobial agent and an amendment during forced-aeration static-pile composting of cow manure, which was mainly aimed to inhibit the pathogens that had not been inactivated by heat during composting. METHODS The mixtures of dairy cow manure and maize straw with addition of 2 % CaCN2 or no addition were composted for 63 days. The physical, chemical and biological changes in compost mixtures were examined during composting. The data were statistically analyzed using ANOVA procedure from SAS software (version 9.0). RESULTS The results showed that the addition of CaCN2 significantly increased the maximum temperature and lengthened the duration of the thermophilic phase, and increased the percent T-N but decreased C/N ratio. For microbiological test, the addition of CaCN2 shortened the time to inactivate E. coli, and increased the total average population of thermophilic bacteria but did not significantly influence that of mesophilic bacteria. CONCLUSION The results indicated that the addition of CaCN2, at least at the additive content of 2 % could benefit the thermophilic phase and the composting could quickly reach the sanitary standard during the composting of manure with maize straw in a forced-aeration static-pile system. This finding will contribute to solve the feces disposal problems.
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Affiliation(s)
- Huasai Simujide
- College of Animal Science, Inner Mongolia Agricultural University, Zhaowuda road, 306, 010018 Hohhot, China
| | - Chen Aorigele
- College of Animal Science, Inner Mongolia Agricultural University, Zhaowuda road, 306, 010018 Hohhot, China
| | - Chun-Jie Wang
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Zhaowuda road, 306, 010018 Hohhot, China
| | - Tian-Hua Zhang
- College of Animal Science, Inner Mongolia Agricultural University, Zhaowuda road, 306, 010018 Hohhot, China
| | - Bai Manda
- College of Animal Science, Inner Mongolia Agricultural University, Zhaowuda road, 306, 010018 Hohhot, China
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Degueurce A, Trémier A, Peu P. Dynamic effect of leachate recirculation on batch mode solid state anaerobic digestion: Influence of recirculated volume, leachate to substrate ratio and recirculation periodicity. BIORESOURCE TECHNOLOGY 2016; 216:553-561. [PMID: 27281433 DOI: 10.1016/j.biortech.2016.05.113] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/26/2016] [Accepted: 05/27/2016] [Indexed: 06/06/2023]
Abstract
Performances of batch mode solid state anaerobic digestion (SSAD) were investigated through several leachate recirculation strategies. Three parameters were shown to particularly influence methane production rates (MPR) and methane yields: the length of the interval between two recirculation events, the leachate to substrate (L:S) ratio and the volume of leachate recirculated. A central composite factor design was used to determine the influence of each parameter on methane production. Results showed that lengthening the interval between two recirculation events reduced methane yield. This effect can be counteracted by recirculating a large volume of leachate at a low L:S ratio. Steady methane production can be obtained by recirculating small amounts of leachate, and by lengthening the interval between two recirculations, regardless of the L:S ratio. However, several combinations of these parameters led to similar performances meaning that leachate recirculation practices can be modified as required by the specific constraints SSAD plants configurations.
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Affiliation(s)
- Axelle Degueurce
- Irstea, UR OPAALE, 17 Avenue de Cucillé-CS 64427, F-35044 Rennes, France; Université Bretagne Loire, F-35044 Rennes, France
| | - Anne Trémier
- Irstea, UR OPAALE, 17 Avenue de Cucillé-CS 64427, F-35044 Rennes, France; Université Bretagne Loire, F-35044 Rennes, France
| | - Pascal Peu
- Irstea, UR OPAALE, 17 Avenue de Cucillé-CS 64427, F-35044 Rennes, France; Université Bretagne Loire, F-35044 Rennes, France.
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Uçaroğlu S, Alkan U. Composting of wastewater treatment sludge with different bulking agents. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2016; 66:288-295. [PMID: 26651372 DOI: 10.1080/10962247.2015.1131205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
UNLABELLED The main objectives of this study were to investigate the compostability of wastewater treatment sludge (WTS) containing different bulking agents (BAs) and to determine the most efficient BA. Four different compost trials consisting of mixtures of wheat straw (WS), plane leaf (PL), corncob (CC) and sunflower stalk (SS) with WTS were performed in laboratory reactors. In all experiments, a mixture of 60% WTS and 40% BA (wet basis) was used. The temperature, dry matter (DM), organic matter (OM), pH, electrical conductivity (EC) and C/N ratio were monitored during the composting process. Evaluation of the operational parameters showed that the highest organic matter degradation (i.e. 37.6%), loss of dry matter (i.e. 29.6%) and temperature (i.e. 64 °C) were achieved for the WTS-CC mixtures. Results also showed that the WTS-SS mixture was also successful in terms of these operational parameters. Use of bulking agents for the treatment of wastewater treatment sludge in composting process is an important issue with regards to process efficiency, economy and disposal of agricultural waste. Corncob and sunflower stalk that were previously not used for the composting of WTS from food industry were shown to be highly successful BA materials in this study. IMPLICATIONS The compostability of wastewater treatment sludge from the food industry with different bulking agents was studied. Wheat straw, plane leaf, corncob, and sunflower stalk were used as bulking agents. The required microbial stabilization and degree of mineralization were achieved with corncobs and sunflower stalks.
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Affiliation(s)
- Selnur Uçaroğlu
- a Uludag University, Faculty of Engineering , Department of Environmental Engineering , Nilufer , Bursa , Turkey
| | - Ufuk Alkan
- a Uludag University, Faculty of Engineering , Department of Environmental Engineering , Nilufer , Bursa , Turkey
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Huiliñir C, Villegas M. Simultaneous effect of initial moisture content and airflow rate on biodrying of sewage sludge. WATER RESEARCH 2015; 82:118-128. [PMID: 26054696 DOI: 10.1016/j.watres.2015.04.046] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 03/18/2015] [Accepted: 04/13/2015] [Indexed: 06/04/2023]
Abstract
The simultaneous effect of initial moisture content (initial Mc) and air-flow rate (AFR) on biodrying performance was evaluated. For the study, a 3(2) factorial design, whose factors were AFR (1, 2 and 3 L/min kg(TS)) and initial Mc (59, 68 and 78% w.b.), was used. Using energy and water mass balance the main routes of water removal, energy use and efficiencies were determined. The results show that initial Mc has a stronger effect on the biodrying than the AFR, affecting the air outlet temperature and improving the water removal, with higher maximum temperatures obtained around 68% and the lowest maximum matrix temperature obtained at initial Mc = 78%.Through the water mass balance it was found that the main mechanism for water removal was the aeration, with higher water removal at intermediate initial Mc (68%) and high AFR (3 L/min kg(TS)). The energy balance indicated that bioreaction is the main energy source for water evaporation, with higher energy produced at intermediate initial Mc (68%). Finally, it was found that low values of initial Mc (59%) improve biodrying efficiency.
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Affiliation(s)
- Cesar Huiliñir
- Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile.
| | - Manuel Villegas
- Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile
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Villegas M, Huiliñir C. Biodrying of sewage sludge: kinetics of volatile solids degradation under different initial moisture contents and air-flow rates. BIORESOURCE TECHNOLOGY 2014; 174:33-41. [PMID: 25463779 DOI: 10.1016/j.biortech.2014.09.136] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 09/23/2014] [Accepted: 09/28/2014] [Indexed: 06/04/2023]
Abstract
This study focuses on the kinetics of the biodegradation of volatile solids (VS) of sewage sludge for biodrying under different initial moisture contents (Mc) and air-flow rates (AFR). For the study, a 3(2) factorial design, whose factors were AFR (1, 2 or 3L/minkgTS) and initial Mc (59%, 68% and 78% w.b.), was used. Using seven kinetic models and a nonlinear regression method, kinetic parameters were estimated and the models were analyzed with two statistical indicators. Initial Mc of around 68% increases the temperature matrix and VS consumption, with higher moisture removal at lower initial Mc values. Lower AFRs gave higher matrix temperatures and VS consumption, while higher AFRs increased water removal. The kinetic models proposed successfully simulate VS biodegradation, with root mean square error (RMSE) between 0.007929 and 0.02744, and they can be used as a tool for satisfactory prediction of VS in biodrying.
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Affiliation(s)
- Manuel Villegas
- Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile
| | - Cesar Huiliñir
- Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile.
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Wang X, Li F, Guo G, Wang S, Boronin A, Wang Q. Temporal Changes in Microbial Metabolic Characteristics in Field-Scale Biopiles Composed of Aged Oil Sludge. ENVIRONMENTAL ENGINEERING SCIENCE 2014; 31:507-513. [PMID: 25228785 PMCID: PMC4161157 DOI: 10.1089/ees.2013.0461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 05/18/2014] [Indexed: 06/03/2023]
Abstract
Disposal of oil sludge, a hazardous waste, is currently a prevalent environmental issue. In this study, two field-scale biopiles were constructed to explore the temporal changes of microbial metabolic characteristics during the biotreatment of aged oil sludge. Bulking agent was mixed thoroughly with oily sludge to form a treated pile. The BIOLOG™ system was used to analyze the community level physiological parameters, including microbial metabolic activity, diversity, and variance. In comparison with the control, the community level physiological parameters of the treated pile were dramatically improved. Microbial metabolic activity of the treated pile was improved by 25.06% calculated from the maximums during the treatment. Microbial diversity index (Shannon index) ranges were improved from 1.64-3.02 (control pile) to 2.34-3.14 (treated pile). The numbers of petroleum-degrading bacteria and the total heterotrophic bacteria were correlated with the environmental temperature, and microbial metabolic characteristics in the treated pile revealed the distinctive carbon resources selection with the addition of cotton stalk. Temporal microbial metabolic characteristics, which have important effect on bioremediation, were revealed in this study.
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Affiliation(s)
- Xiang Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Fasheng Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Guanlin Guo
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Shijie Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Alexander Boronin
- Institute of Biochemistry and Physiology of Microorganisms, Russia Academy of Sciences, Pushchino, Russia
| | - Qunhui Wang
- School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing, China
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12
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Huiliñir C, Villegas M. Biodrying of pulp and paper secondary sludge: kinetics of volatile solids biodegradation. BIORESOURCE TECHNOLOGY 2014; 157:206-213. [PMID: 24561626 DOI: 10.1016/j.biortech.2014.01.109] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 01/23/2014] [Accepted: 01/25/2014] [Indexed: 06/03/2023]
Abstract
This study focuses on the kinetics of volatile solids (VS) biodegradation of the biodrying process using pulp and paper secondary sludge. The experiments were carried out with air-flow rates of 0.51, 1.61, 3.25 and 5.26L/minkgVS) and initial moisture content of 64-66% w.b. Using five kinetic models and a nonlinear regression method, kinetic parameters were estimated and the models were analyzed with two statistical indicators. Higher air-flow rates cause greater moisture content reduction, lower temperature in the matrix, and lower VS reduction. At an air-flow rate as high as 5.26L/minkgVS there is no biodrying but only convective drying. The kinetic models used successfully simulate the VS biodegradation under biodrying conditions, with a root mean square error (RMSE) between 0.007929 and 0.02744. In conclusion, we show for the first time that VS biodegradation in the biodrying process can be successfully modeled with a kinetic model.
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Affiliation(s)
- Cesar Huiliñir
- Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile.
| | - Manuel Villegas
- Departamento de Ingeniería Química, Universidad de Santiago de Chile, Casilla 442, Correo 2, Santiago, Chile
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13
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Ding A, Qu F, Liang H, Guo S, Ren Y, Xu G, Li G. Effect of adding wood chips on sewage sludge dewatering in a pilot-scale plate-and-frame filter press process. RSC Adv 2014. [DOI: 10.1039/c4ra03584d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Schematic mechanism of the effect of adding wood chips on sludge dewatering: (a) sludge without conditioning; (b) sludge with chemical conditioning; (c) sludge with chemical and physical conditioning; and (d) a physical image of a dewatered sludge cake with wood chip conditioning.
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Affiliation(s)
- An Ding
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE)
- Harbin Institute of Technology
- Harbin, P.R. China
| | - Fangshu Qu
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE)
- Harbin Institute of Technology
- Harbin, P.R. China
| | - Heng Liang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE)
- Harbin Institute of Technology
- Harbin, P.R. China
| | - Shaodong Guo
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE)
- Harbin Institute of Technology
- Harbin, P.R. China
| | - Yuhui Ren
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE)
- Harbin Institute of Technology
- Harbin, P.R. China
| | - Guoren Xu
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE)
- Harbin Institute of Technology
- Harbin, P.R. China
| | - Guibai Li
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE)
- Harbin Institute of Technology
- Harbin, P.R. China
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Chowdhury MA, de Neergaard A, Jensen LS. Prediction of changes in important physical parameters during composting of separated animal slurry solid fractions. ENVIRONMENTAL TECHNOLOGY 2014; 35:220-231. [PMID: 24600860 DOI: 10.1080/09593330.2013.824008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Solid-liquid separation of animal slurry, with solid fractions used for composting, has gained interest recently. However, efficient composting of separated animal slurry solid fractions (SSFs) requires a better understanding of the process dynamics in terms of important physical parameters and their interacting physical relationships in the composting matrix. Here we monitored moisture content, bulk density, particle density and air-filled porosity (AFP) during composting of SSF collected from four commercially available solid-liquid separators. Composting was performed in laboratory-scale reactors for 30 days (d) under forced aeration and measurements were conducted on the solid samples at the beginning of composting and at 10-d intervals during composting. The results suggest that differences in initial physical properties of SSF influence the development of compost maximum temperatures (40-70 degreeC). Depending on SSF, total wet mass and volume losses (expressed as % of initial value) were up to 37% and 34%, respectively. After 30 d of composting, relative losses of total solids varied from 17.9% to 21.7% and of volatile solids (VS) from 21.3% to 27.5%, depending on SSF. VS losses in all composts showed different dynamics as described by the first-order kinetic equation. The estimated component particle density of 1441 kg m-3 for VS and 2625 kg m-3 for fixed solids can be used to improve estimates of AFP for SSF within the range tested. The linear relationship between wet bulk density and AFP reported by previous researchers held true for SSF.
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Affiliation(s)
- Md Albarune Chowdhury
- Department ofAgriculture and Ecology, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark.
| | - Andreas de Neergaard
- Department ofAgriculture and Ecology, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Lars Stoumann Jensen
- Department ofAgriculture and Ecology, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
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Makan A, Assobhei O, Mountadar M. Effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco. IRANIAN JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2013; 10:3. [PMID: 23369502 PMCID: PMC3561115 DOI: 10.1186/1735-2746-10-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 12/31/2012] [Indexed: 11/10/2022]
Abstract
This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts. For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times. This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications.
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Affiliation(s)
- Abdelhadi Makan
- Water and Environment Laboratory, Chemistry Department, Faculty of Science, University Chouaib Doukkali, P,O, Box 20, El Jadida 24000, Morocco.
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Baptista M, Silveira A, Antunes F. Theoretical analysis of the kinetic performance of laboratory- and full-scale composting systems. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2012; 30:700-707. [PMID: 22452956 DOI: 10.1177/0734242x11433528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Composting research at laboratory-scale is critical for the development of optimized full-scale plants. Discrepancies between processes at laboratory-scale and full-scale systems have been investigated in terms of heat balances, but a kinetic analysis of this issue is still missing. In this study, the composting rate at laboratory-scale was, on average, between 1.9 and 5.7 times faster than in full-scale systems for a set of published studies using municipal solid waste, food waste or similar materials. Laboratory-scale performance and full-scale systems were limited to 71 and 46%, respectively, of their maximum potential due to poor management of environmental process conditions far from their optimum. The main limiting environmental factor was found to be moisture content, followed by temperature. Besides environmental factors, waste composition and particle size were identified as factors accounting for kinetic differences between laboratory- and full-scale systems. Overall, this study identifies those factors that affect the kinetics of the composting process most and revealed a significant margin for reducing process time in full-scale composting.
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Affiliation(s)
- Marco Baptista
- Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, Caparica, Portugal.
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17
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Silva PRP, Barbisan LF, Dagli MLZ, Saldiva PHN. Sewage sludge does not induce genotoxicity and carcinogenesis. Genet Mol Biol 2012; 35:657-63. [PMID: 23055806 PMCID: PMC3459417 DOI: 10.1590/s1415-47572012005000054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 03/18/2012] [Indexed: 11/22/2022] Open
Abstract
Through a series of experiments, the genotoxic/mutagenic and carcinogenic potential of sewage sludge was assessed. Male Wistar rats were randomly assigned to four groups: Group 1 - negative control; Group 2 - liver carcinogenesis initiated by diethylnitrosamine (DEN; 200 mg/kg i.p.); Group 3 and G4-liver carcinogenesis initiated by DEN and fed 10,000 ppm or 50,000 ppm of sewage sludge. The animals were submitted to a 70% partial hepatectomy at the 3(rd) week. Livers were processed for routine histological analysis and immunohistochemistry, in order to detect glutathione S-transferase positive altered hepatocyte foci (GST-P(+) AHF). Peripheral blood samples for the comet assay were obtained from the periorbital plexus immediately prior to sacrificing. Polychromatic erythrocytes (PCEs) were analyzed in femoral bone-marrow smears, and the frequencies of those micronucleated (MNPCEs) registered. There was no sewage-sludge-induced increase in frequency of either DNA damage in peripheral blood leucocytes, or MNPCEs in the femoral bone marrow. Also, there was no increase in the levels of DNA damage, in the frequency of MNPCEs, and in the development of GST-P AHF when compared with the respective control group.
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Affiliation(s)
- Paula Regina Pereira Silva
- Departamento de Patologia, Núcleo de Avaliação do Impacto Ambiental sobre a Saúde Humana, Faculdade de Medicina, Universidade Estadual Paulista “Júlio Mesquita Filho”, Botocatu, SP, Brazil
- Departamento de Patologia, Laboratório de Poluição do Ar, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Luis Fernando Barbisan
- Departamento de Morfologia, Instituto de Biociências, Universidade Estadual Paulista “Júlio Mesquita Filho”, Botucatu, SP, Brazil
| | - Maria Lúcia Zaidan Dagli
- Departamento de Patologia, Faculdade de Medicina Veterinária e Ciência Animal, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Paulo Hilário Nascimento Saldiva
- Departamento de Patologia, Laboratório de Poluição do Ar, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
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Wang X, Wang Q, Wang S, Li F, Guo G. Effect of biostimulation on community level physiological profiles of microorganisms in field-scale biopiles composed of aged oil sludge. BIORESOURCE TECHNOLOGY 2012; 111:308-15. [PMID: 22357295 DOI: 10.1016/j.biortech.2012.01.158] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 01/25/2012] [Accepted: 01/29/2012] [Indexed: 05/13/2023]
Abstract
Four biopiles were constructed for the bioremediation of total petroleum hydrocarbons (TPHs) in aged oily sludge by indigenous microorganisms. Three biopiles were treated with bulking agent, nutrients or their combination with the fourth pile serving as the control. Responses of microbial community level physiological profiles (CLPPs) to these biostimulation strategies were estimated, and variances among three layers within each biopile were evaluated. Microbial metabolic activity and diversity and the numbers of two species of bacteria were significantly enhanced by the addition of bulking agent, which also made the layers more homogeneous. In contrast, the application of large amounts of nutrients had a suppressing effect on the microbes. After 220 days, 49.62% of TPHs were removed from the middle layer of the bulking agent pile, whereas only 20.44% were removed from the inner layer of the control. This study aims to provide experience to improve the remediation efficiency of future investigations.
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Affiliation(s)
- Xiang Wang
- School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China
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Illa J, Prenafeta-Boldú FX, Bonmatí A, Flotats X. Empirical characterisation and mathematical modelling of settlement in composting batch reactors. BIORESOURCE TECHNOLOGY 2012; 104:451-458. [PMID: 22100237 DOI: 10.1016/j.biortech.2011.10.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Revised: 10/03/2011] [Accepted: 10/11/2011] [Indexed: 05/31/2023]
Abstract
The settlement of organic matter during composting was measured at different levels during the active biodegradation phase in forced-aerated static reactors loaded with different mixtures of organic wastes. The temperature evolution and the concentration of oxygen and carbon dioxide were also recorded in the exhaust gases. Two two-parameter equations and their generalised three-parameter form were fitted to the experimental data and their capability to predict settlement as a function of time was discussed. The settlement field inside the reactors was successfully described with a linear profile. At any given time and vertical position, mass settlement was proportional to the initial height after reactor loading. Furthermore, a relationship linking settlement to biological activity was also proposed. Under all tested experimental conditions, settlement showed a clear correlation with the cumulative oxygen consumption that was modelled with a three parameter equation.
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Affiliation(s)
- Josep Illa
- Dept. of Computing and Industrial Engineering, Universitat de Lleida, Avgda. Jaume II 69, E-25001 Lleida, Spain.
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Zhao L, Wang XY, Gu WM, Shao LM, He PJ. Distribution of C and N in soluble fractionations for characterizing the respective biodegradation of sludge and bulking agents. BIORESOURCE TECHNOLOGY 2011; 102:10745-10749. [PMID: 21962535 DOI: 10.1016/j.biortech.2011.08.111] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2011] [Revised: 08/23/2011] [Accepted: 08/26/2011] [Indexed: 05/31/2023]
Abstract
This study utilized C and N distribution in different soluble fractionations instead of the routine C/N ratio to characterize the respective biodegradation of sludge and bulking agents in bio-drying or composting. For sludge, C was mainly distributed (31.8%) in the neutral detergent soluble and water insoluble fraction (SOL), whereas it was mainly distributed in the cellulose-like fraction (CEL) for straw (39.5%) and sawdust (45.8%). A large proportion of N was in the 35 °C water-soluble fraction (W35 °C) for sludge (34.0%) and straw (52.5%), while for sawdust it was in the lignin-like fraction (LIG; 49.4%). For sludge, the C and N loss were mainly contributed by W35 °C (36.9% and 52.4%). The other fractions also contributed a lot. For straw, 22.4% of C and 89.8% of N lose in W35 °C. The hemicellulose-like (HEM) and CEL fraction also gave a large contribution to C loss (28.5% and 40.1%), while contributing little to N loss.
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Affiliation(s)
- Ling Zhao
- Institute of Waste Treatment and Reclamation, State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
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21
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Komilis D, Evangelou A, Voudrias E. Monitoring and optimizing the co-composting of dewatered sludge: a mixture experimental design approach. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2011; 92:2241-2249. [PMID: 21565440 DOI: 10.1016/j.jenvman.2011.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 04/17/2011] [Accepted: 04/23/2011] [Indexed: 05/30/2023]
Abstract
The management of dewatered wastewater sludge is a major issue worldwide. Sludge disposal to landfills is not sustainable and thus alternative treatment techniques are being sought. The objective of this work was to determine optimal mixing ratios of dewatered sludge with other organic amendments in order to maximize the degradability of the mixtures during composting. This objective was achieved using mixture experimental design principles. An additional objective was to study the impact of the initial C/N ratio and moisture contents on the co-composting process of dewatered sludge. The composting process was monitored through measurements of O(2) uptake rates, CO(2) evolution, temperature profile and solids reduction. Eight (8) runs were performed in 100 L insulated air-tight bioreactors under a dynamic air flow regime. The initial mixtures were prepared using dewatered wastewater sludge, mixed paper wastes, food wastes, tree branches and sawdust at various initial C/N ratios and moisture contents. According to empirical modeling, mixtures of sludge and food waste mixtures at 1:1 ratio (ww, wet weight) maximize degradability. Structural amendments should be maintained below 30% to reach thermophilic temperatures. The initial C/N ratio and initial moisture content of the mixture were not found to influence the decomposition process. The bio C/bio N ratio started from around 10, for all runs, decreased during the middle of the process and increased to up to 20 at the end of the process. The solid carbon reduction of the mixtures without the branches ranged from 28% to 62%, whilst solid N reductions ranged from 30% to 63%. Respiratory quotients had a decreasing trend throughout the composting process.
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Affiliation(s)
- Dimitrios Komilis
- Laboratory of Solid and Hazardous Waste Management, Department of Environmental Engineering, Democritus University of Thrace, Xanthi GR-671 00, Greece.
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Barrena R, Turet J, Busquets A, Farrés M, Font X, Sánchez A. Respirometric screening of several types of manure and mixtures intended for composting. BIORESOURCE TECHNOLOGY 2011; 102:1367-1377. [PMID: 20888220 DOI: 10.1016/j.biortech.2010.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 09/01/2010] [Accepted: 09/03/2010] [Indexed: 05/29/2023]
Abstract
The viability of mixtures from manure and agricultural wastes as composting sources were systematically studied using a physicochemical and biological characterization. The combination of different parameters such as C:N ratio, free air space (FAS) and moisture content can help in the formulation of the mixtures. Nevertheless, the composting process may be challenging, particularly at industrial scales. The results of this study suggest that if the respirometric potential is known, it is possible to predict the behaviour of a full scale composting process. Respiration indices can be used as a tool for determining the suitability of composting as applied to manure and complementary wastes. Accordingly, manure and agricultural wastes with a high potential for composting and some proposed mixtures have been characterized in terms of respiration activity. Specifically, the potential of samples to be composted has been determined by means of the oxygen uptake rate (OUR) and the dynamic respirometric index (DRI). During this study, four of these mixtures were composted at full scale in a system consisting of a confined pile with forced aeration. The biological activity was monitored by means of the oxygen uptake rate inside the material (OURinsitu). This new parameter represents the real activity of the process. The comparison between the potential respirometric activities at laboratory scale with the in situ respirometric activity observed at full scale may be a useful tool in the design and optimization of composting systems for manure and other organic agricultural wastes.
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Affiliation(s)
- Raquel Barrena
- Composting Research Group, Department of Chemical Engineering, Escola d'Enginyeria, Universitat Autònoma de Barcelona, Bellaterra, Cerdanyola, 08193 Barcelona, Spain
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23
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Zhao L, Gu WM, He PJ, Shao LM. Effect of air-flow rate and turning frequency on bio-drying of dewatered sludge. WATER RESEARCH 2010; 44:6144-52. [PMID: 20673952 DOI: 10.1016/j.watres.2010.07.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2010] [Revised: 05/11/2010] [Accepted: 07/04/2010] [Indexed: 05/24/2023]
Abstract
Sludge bio-drying is an approach for biomass energy utilization, in which sludge is dried by means of the heat generated by aerobic degradation of its organic substances. The study aimed at investigating the interactive influence of air-flow rate and turning frequency on water removal and biomass energy utilization. Results showed that a higher air-flow rate (0.0909m(3)h(-1)kg(-1)) led to lower temperature than did the lower one (0.0455m(3)h(-1)kg(-1)) by 17.0% and 13.7% under turning per two days and four days. With the higher air-flow rate and lower turning frequency, temperature cumulation was almost similar to that with the lower air-flow rate and higher turning frequency. The doubled air-flow rate improved the total water removal ratio by 2.86% (19.5gkg(-1) initial water) and 11.5% (75.0gkg(-1) initial water) with turning per two days and four days respectively, indicating that there was no remarkable advantage for water removal with high air-flow rate, especially with high turning frequency. The heat used for evaporation was 60.6-72.6% of the total heat consumption (34,400-45,400kJ). The higher air-flow rate enhanced volatile solids (VS) degradation thus improving heat generation by 1.95% (800kJ) and 8.96% (3200kJ) with turning per two days and four days. With the higher air-flow rate, heat consumed by sensible heat of inlet air and heat utilization efficiency for evaporation was higher than the lower one. With the higher turning frequency, sensible heat of materials and heat consumed by turning was higher than lower one.
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Affiliation(s)
- Ling Zhao
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
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Chang JI, Chen YJ. Effects of bulking agents on food waste composting. BIORESOURCE TECHNOLOGY 2010; 101:5917-5924. [PMID: 20385493 DOI: 10.1016/j.biortech.2010.02.042] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Revised: 02/07/2010] [Accepted: 02/08/2010] [Indexed: 05/29/2023]
Abstract
The effects of rice husk, sawdust and rice bran on the composting process of food waste were studied in a 180-L laboratory composter based on a mixture experimental design. Linear and quadratic models of seven important process characteristics (composting and acidification times, lowest and final pH values, highest temperature, the water-soluble organic carbon to water-soluble organic nitrogen (C(OW)/N(OW) ratio), and the water-soluble organic carbon to total organic nitrogen (C(OW)/N(OT)) ratio) in terms of fractional compositions of bulking agents as well as the water absorption capacity and the free air space of the composting matrix were developed.
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Affiliation(s)
- James I Chang
- Department of Safety, Health and Environmental Engineering, National Kaohsiung First University of Science and Technology, Kaohsiung, Taiwan, ROC.
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