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Rasaq WA, Thiruchenthooran V, Wirkijowska K, Valentin M, Bobak Ł, Adaobi Igwegbe C, Białowiec A. Hydrothermal carbonization of combined food waste: A critical evaluation of emergent products. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 189:44-57. [PMID: 39173471 DOI: 10.1016/j.wasman.2024.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Revised: 07/22/2024] [Accepted: 08/15/2024] [Indexed: 08/24/2024]
Abstract
Hydrothermal carbonization (HTC) increasingly appears as an eco-friendly method for managing food waste (FW). In this work, a combination of FW was subjected to HTC, and products were critically evaluated. This involved a lab-scale pressure reactor and optimization of HTC conditions: temperature (220-340 °C) and residence time (90-260 min) via central composite design type of response surface methodology (CCD-RSM). Results showed varying temperatures and residence time to impact the hydrochar (HC) and hydrothermal carbonization aqueous phase (HTC-AP) properties. Although HC produced through HTC exhibited lower ash content (<2%) despite higher fixed carbon (>55 %) with respect to the raw FW, the heating value of HC ranged from 19.2 to 32.5 MJ/kg. Temperature primarily influenced FW conversion, affecting carbonaceous properties. Saturated fatty acids (SFA) were found to be predominant in the HTC-AP under all tested operating conditions (77.3, 48.4, and 37.1 wt% for HTC at 340, 280, and 220 °C in 180 min, respectively). Total phosphorus recovery in HC and HTC-AP respectively peaked at 340 °C and 220 °C in 180 min. The study concludes that HTC holds promise for energy-dense biofuel production, nutrient recovery, and fostering a circular economy.
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Affiliation(s)
- Waheed A Rasaq
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 37a Chełmońskiego Str., Wrocław 51-630, Poland.
| | - Vaikunthavasan Thiruchenthooran
- Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Norwida 25, Wrocław 50-375, Poland.
| | - Katarzyna Wirkijowska
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 37a Chełmońskiego Str., Wrocław 51-630, Poland.
| | - Marvin Valentin
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 37a Chełmońskiego Str., Wrocław 51-630, Poland.
| | - Łukasz Bobak
- Department of Functional Food Products Development, Wroclaw University of Environmental and Life Sciences, Wrocław 51-630, Poland.
| | - Chinenye Adaobi Igwegbe
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 37a Chełmońskiego Str., Wrocław 51-630, Poland; Department of Chemical Engineering, Nnamdi Azikiwe University, P.M.B. 5025, Awka 420218, Nigeria.
| | - Andrzej Białowiec
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 37a Chełmońskiego Str., Wrocław 51-630, Poland.
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Valentin MT, Białowiec A. Impact of using glucose as a sole carbon source to analyze the effect of biochar on the kinetics of biomethane production. Sci Rep 2024; 14:8656. [PMID: 38622318 PMCID: PMC11384929 DOI: 10.1038/s41598-024-59313-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 04/09/2024] [Indexed: 04/17/2024] Open
Abstract
The adaptation of biochar in anaerobic digestion (AD) positively influences the conversion of substrate to biomethane and promotes system stability. This study investigated the influence of biochar (BC) doses (0 to 8 g/L) on the Biochemical Methane Potential (BMP) of glucose during a 60-day AD in a mesophilic batch-type reactor. The first 6.5 weeks of the experimentation were dedicated to the microorganism's adaptation to the biochar and degradation of organics from the used inoculum (3 phases of the glucose feeding). The last 2 weeks (4th phase of glucose feeding) represented the assumption, that glucose is the sole carbon source in the system. A machine learning model based on the autoregressive integrated moving average (ARIMA) method was used to model the cumulative BMP. The results showed that the BMP increased with the amount of BC added. The highest BMP was obtained at a dose of 8 g/L, with a maximum cumulative BMP of 390.33 mL CH4/g-VS added. Likewise, the system showed stability in the pH (7.17 to 8.17). In contrast, non-amended reactors produced only 135.06 mL CH4/g-VS and became acidic at the end of the operation. Reducing the influence of carbon from inoculum, sharpened the positive effect of BC on the kinetics of biomethane production from glucose.
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Affiliation(s)
- Marvin T Valentin
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 51-630, Wroclaw, Poland
- Department of Science and Technology, Engineering and Industrial Research, National Research Council of the Philippines, Taguig, Philippines
- Department of Agricultural and Biosystems Engineering, Benguet State University, Km. 5, La Trinidad, 2601, Benguet, Philippines
| | - Andrzej Białowiec
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 51-630, Wroclaw, Poland.
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Liu J, Jia H, Xu Z, Wang T, Mei M, Chen S, Li J, Zhang W. An impressive pristine biochar from food waste digestate for arsenic(V) removal from water: Performance, optimization, and mechanism. BIORESOURCE TECHNOLOGY 2023; 387:129586. [PMID: 37516138 DOI: 10.1016/j.biortech.2023.129586] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Anaerobic digestion has become a global practice for valorizing food waste, but the recycling of the digestate (FWD) remains challenging. This study aimed to address this issue by utilizing FWD as a low-cost feedstock for Ca-rich biochar production. The results demonstrated that biochar pyrolyzed at 900 °C exhibited impressive As(V) adsorption performance without any modifications. Kinetic analysis suggested As(V) was chemisorbed onto CDBC9, while isotherm data conformed well to Langmuir model, indicating monolayer adsorption with a maximum capacity of 76.764 mg/g. Further analysis using response surface methodology revealed that pH value and adsorbent dosage were significant influencing factors, and density functional theory (DFT) calculation visualized the formation of ionic bonds between HAsO42- and CaO(110) and Ca(OH)2(101) surfaces. This work demonstrated the potential of using FWD for producing Ca-rich biochar, providing an effective solution for As(V) removal and highlighting the importance of waste material utilization in sustainable environmental remediation.
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Affiliation(s)
- Jingxin Liu
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan 430073, China
| | - Hang Jia
- Beijing Graphene Institute, Beijing 100095, China
| | - Zelin Xu
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Teng Wang
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan 430073, China
| | - Meng Mei
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan 430073, China
| | - Si Chen
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan 430073, China
| | - Jinping Li
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China; Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan 430073, China
| | - Wenjuan Zhang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
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Valentin MT, Świechowski K, Białowiec A. Influence of Pre-Incubation of Inoculum with Biochar on Anaerobic Digestion Performance. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6655. [PMID: 37895637 PMCID: PMC10608094 DOI: 10.3390/ma16206655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 10/05/2023] [Accepted: 10/09/2023] [Indexed: 10/29/2023]
Abstract
The application of biochar as an additive to enhance the anaerobic digestion (AD) of biomass has been extensively studied from various perspectives. This study reported, for the first time, the influence of biochar incubation in the inoculum on the anaerobic fermentation of glucose in a batch-type reactor over 20 days. Three groups of inoculum with the same characteristics were pre-mixed once with biochar for different durations: 21 days (D21), 10 days (D10), and 0 days (D0). The BC was mixed in the inoculum at a concentration of 8.0 g/L. The proportion of the inoculum and substrate was adjusted to an inoculum-to-substrate ratio of 2.0 based on the volatile solids. The results of the experiment revealed that D21 had the highest cumulative methane yield, of 348.98 mL, compared to 322.66, 290.05, and 25.15 mL obtained from D10, D0, and the control, respectively. Three models-modified Gompertz, first-order, and Autoregressive Integrated Moving Average (ARIMA)-were used to interpret the biomethane production. All models showed promising fitting of the cumulative biomethane production, as indicated by high R2 and low RMSE values. Among these models, the ARIMA model exhibited the closest fit to the actual data. The biomethane production rate, derived from the modified Gompertz Model, increased as the incubation period increased, with D21 yielding the highest rate of 31.13 mL/gVS. This study suggests that the application of biochar in the anaerobic fermentation of glucose, particularly considering the short incubation period, holds significant potential for improving the overall performance of anaerobic digestion.
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Affiliation(s)
- Marvin T. Valentin
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 51-630 Wroclaw, Poland or (M.T.V.); (K.Ś.)
- Benguet State University, Km. 5, La Trinidad, Benguet 2601, Philippines
| | - Kacper Świechowski
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 51-630 Wroclaw, Poland or (M.T.V.); (K.Ś.)
| | - Andrzej Białowiec
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 51-630 Wroclaw, Poland or (M.T.V.); (K.Ś.)
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Valentin MT, Luo G, Zhang S, Białowiec A. Direct interspecies electron transfer mechanisms of a biochar-amended anaerobic digestion: a review. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:146. [PMID: 37784139 PMCID: PMC10546780 DOI: 10.1186/s13068-023-02391-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 09/09/2023] [Indexed: 10/04/2023]
Abstract
This paper explores the mechanisms of biochar that facilitate direct interspecies electron transfer (DIET) among syntrophic microorganisms leading to improved anaerobic digestion. Properties such as specific surface area (SSA), cation exchange capacity (CEC), presence of functional groups (FG), and electrical conductivity (EC) were found favorable for increased methane production, reduction of lag phase, and adsorption of inhibitors. It is revealed that these properties can be modified and are greatly affected by the synthesizing temperature, biomass types, and residence time. Additionally, suitable biochar concentration has to be observed since dosage beyond the optimal range can create inhibitions. High organic loading rate (OLR), pH shocks, quick accumulation and relatively low degradation of VFAs, and the presence of heavy metals and toxins are the major inhibitors identified. Summaries of microbial community analysis show fermentative bacteria and methanogens that are known to participate in DIET. These are Methanosaeta, Methanobacterium, Methanospirillum, and Methanosarcina for the archaeal community; whereas, Firmicutes, Proteobacteria, Synergistetes, Spirochetes, and Bacteroidetes are relatively for bacterial analyses. However, the number of defined cocultures promoting DIET is very limited, and there is still a large percentage of unknown bacteria that are believed to support DIET. Moreover, the instantaneous growth of participating microorganisms has to be validated throughout the process.
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Affiliation(s)
- Marvin T. Valentin
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 51-630 Wroclaw, Poland
- Department of Science and Technology, Engineering and Industrial Research, National Research Council of the Philippines, Taguig, Philippines
- Benguet State University, Km. 5, La Trinidad, 2601 Benguet, Philippines
| | - Gang Luo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433 China
- Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai, 200438 China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092 China
| | - Shicheng Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433 China
- Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai, 200438 China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092 China
| | - Andrzej Białowiec
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, 51-630 Wroclaw, Poland
- Department of Agricultural and Biosystems Engineering, Iowa State University, 605 Bissell Road, Ames, IA 50011 USA
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Rosik J, Łyczko J, Marzec Ł, Stegenta-Dąbrowska S. Application of Composts' Biochar as Potential Sorbent to Reduce VOCs Emission during Kitchen Waste Storage. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6413. [PMID: 37834550 PMCID: PMC10573545 DOI: 10.3390/ma16196413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/13/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023]
Abstract
It is expected that due to the new European Union regulation focus on waste management, managing kitchen waste will become more important in the future, especially in households. Therefore, it is crucial to develop user-friendly and odour-free containers to store kitchen waste. The study aimed to test the effectiveness of composts' biochar in reducing noxious odours and volatile organic compounds (VOCs) released during kitchen waste storage. Various amounts of compost biochar (0%, 1%, 5%, and 10%) were added to food waste samples and incubated for seven days at 20 °C. The released VOCs were analysed on days 1, 3, and 7 of the storage simulation process. The results indicated that adding 5-10% of composts' biochar to kitchen waste significantly reduced the emissions in 70% of the detected VOCs compounds. Furthermore, composts' biochar can be used to eliminate potential odour components and specific dangerous VOCs such as ethylbenzene, o-xylene, acetic acid, and naphthalene. A new composts' biochar with a unique composition was particularly effective in reducing VOCs and could be an excellent solution for eliminating odours in kitchen waste containers.
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Affiliation(s)
- Joanna Rosik
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, Chełmońskiego Str. 37a, 51-630 Wroclaw, Poland; (J.R.); (Ł.M.)
| | - Jacek Łyczko
- Faculty of Biotechnology and Food Science, Wroclaw University of Environmental and Life Sciences, 50-375 Wroclaw, Poland;
| | - Łukasz Marzec
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, Chełmońskiego Str. 37a, 51-630 Wroclaw, Poland; (J.R.); (Ł.M.)
| | - Sylwia Stegenta-Dąbrowska
- Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, Chełmońskiego Str. 37a, 51-630 Wroclaw, Poland; (J.R.); (Ł.M.)
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Li P, Zhao T, Zhao Z, Tang H, Feng W, Zhang Z. Biochar Derived from Chinese Herb Medicine Residues for Rhodamine B Dye Adsorption. ACS OMEGA 2023; 8:4813-4825. [PMID: 36777604 PMCID: PMC9909799 DOI: 10.1021/acsomega.2c06968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
In this study, one well-known CHM residue (Atropa belladonna L., ABL) was used to prepare biochar capable of adsorbing rhodamine B (RhB) with an ultrahigh surface area for the first time. Three micropore-rich ABL biochars including ABL@ZnCl2 (1866 m2/g), ABL@H3PO4 (1488 m2/g), and ABL@KOH (590 m2/g) were obtained using the one-step carbonization method with activation agents (ZnCl2, H3PO4, and KOH) via chemical activation and carbonization at 500 °C, and their adsorption performance for RhB was systematically studied with adsorption kinetics, isotherms, and thermodynamics. Through pore diffusion, π-π interaction, and hydrogen bonding, ABL biochar had excellent adsorption performance for RhB. Moreover, when C 0 was 200 mg/L, biochar dosage was 1 g/L, and the contact time was 120 min; the maximum RhB adsorption capacity and removal efficiency on ABL@ZnCl2 and ABL@H3PO4 were 190.63 mg/g, 95% and 184.70 mg/g, 92%, respectively, indicating that it was feasible to prepare biochar from the ABL residue for RhB adsorption. The theoretical maximum adsorption capacities of ABL@ZnCl2 and ABL@H3PO4 for RhB were 263.19 mg/g and 309.11 mg/g at 25 °C, respectively. Furthermore, the prepared biochar showed good economic applicability, with pay back of USD 972/t (ABL@ZnCl2) and USD 987/t (ABL@H3PO4), respectively. More importantly, even after five cycles, ABL@H3PO4 biochar still showed great RhB removal efficiency, suggesting that it had a good application prospect and provided a new method for the resource utilization of traditional CHM residues. Additionally, pore diffusion, π-π interactions, and hydrogen bonding all play roles in the physical adsorption of RhB on ABL biochar. π-π interactions dominated in the early stage of RhB adsorption on ABL@H3PO4, while pore diffusion played a crucial role in the whole adsorption process on both adsorbents.
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Affiliation(s)
- Pengwei Li
- College
of Pharmacy, Henan University of Chinese
Medicine, Zhengzhou450046, China
| | - Ting Zhao
- College
of Pharmacy, Henan University of Chinese
Medicine, Zhengzhou450046, China
| | - Ziheng Zhao
- College
of Pharmacy, Henan University of Chinese
Medicine, Zhengzhou450046, China
| | - Hanxiao Tang
- College
of Chinese Medical Sciences, Henan University
of Chinese Medicine, Zhengzhou450046, China
| | - Weisheng Feng
- College
of Pharmacy, Henan University of Chinese
Medicine, Zhengzhou450046, China
| | - Zhijuan Zhang
- College
of Pharmacy, Henan University of Chinese
Medicine, Zhengzhou450046, China
- Institute
of Mass Spectrometer and Atmospheric Environment, Jinan University, Guangzhou510632, China
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Syguła E, Gałęzowska M, Białowiec A. Enhanced Production of Biogas Using Biochar-Sulfur Composite in the Methane Fermentation Process. MATERIALS 2022; 15:ma15134517. [PMID: 35806641 PMCID: PMC9267185 DOI: 10.3390/ma15134517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/14/2022] [Accepted: 06/23/2022] [Indexed: 11/22/2022]
Abstract
The methane fermentation of organic waste is one way to minimize organic waste, which accounts for 77% of the global municipal waste stream. The use of biochar as an additive for methane fermentation has been shown to increase the production potential of biogas. Sulfur waste has a potential application to synergistic recycling in a form of composites with other materials including biochar. A composite product in the form of a mixture of biochar and molten sulfur has been proposed. In this experiment, additions of the sulfur−biochar composite (SBC) were tested to improve the fermentation process. The biochar was produced from apple chips under the temperature of 500 °C. The ground biochar and sulfur (<1 mm particle size) were mixed in the proportion of 40% biochar and 60% sulfur and heated to 140 °C for sulfur melting. After cooling, the solidified composite was ground. The SBC was added in the dose rate of 10% by dry mass of prepared artificial kitchen waste. Wet anaerobic digestion was carried out in the batch reactors under a temperature of 37 °C for 21 days. As an inoculum, the digestate from Bio-Wat Sp. z. o. o., Świdnica, Poland, was used. The results showed that released biogas reached 672 mL × gvs−1, and the yield was 4% higher than in the variant without the SBC. Kinetics study indicated that the biogas production constant rate reached 0.214 d−1 and was 4.4% higher than in the variant without the SBC.
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Abstract
The efficiency of methane production by anaerobic digestion (AD), during which energy is generated from organic waste, can be increased in various ways. Recent research developments have increased the volume of gas production during AD using biochar. Previous studies have used food waste itself in AD, or, added wood-biochar or sewage sludge charcoal as an accelerant of the AD process. The application of food-waste biochar in AD using activated sludge has not yet been studied and is considered a potential method of utilizing food waste. Therefore, this study investigated the use of biochar prepared by the thermal decomposition of food waste as an additive to AD tanks to increase methane production. The addition of food-waste biochar at 1% of the digestion tank volume increased the production of digestion gas by approximately 10% and methane by 4%. We found that food-waste biochar served as a medium with trace elements that promoted the proliferation of microorganisms and increased the efficiency of AD.
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Malinowski M, Famielec S. Impact of Biochar Addition and Air-Flow Rate on Ammonia and Carbon Dioxide Concentration in the Emitted Gases from Aerobic Biostabilization of Waste. MATERIALS 2022; 15:ma15051771. [PMID: 35269003 PMCID: PMC8911222 DOI: 10.3390/ma15051771] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 02/20/2022] [Accepted: 02/23/2022] [Indexed: 02/01/2023]
Abstract
Application of additives to waste may influence the course of the biostabilization process and contribute to its higher effectiveness, as well as to a reduction in greenhouse gas and ammonia (NH3) emission from this process. This paper presents research on the impact of biochar addition on the course of the biostabilization process of an undersized fraction from municipal solid waste (UFMSW) in terms of temperature changes, CO2 concentration in the exhaust gases, NH3 emission from the process, as well as changes in the carbon and nitrogen content in the processed waste. Six different biochar additives and three different air-flow rates were investigated for 21 days. It was found that biochar addition contributes to extending the thermophilic phase duration (observed in the case of the addition of 3% and 5% of biochar). The concentration of CO2 in exhaust gases was closely related to the course of temperature changes. The highest concentration of CO2 in the process gases (approx. 18–19%) was recorded for the addition of 10% and 20% of biochar at the lowest air-flow rate applied. It was found that the addition of 3% or a higher amount of biochar reduces nitrogen losses in the processed UFMSW and reduces NH3 emission by over 90% compared to the control.
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