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1.
Heliyon ; 10(8): e29618, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38699720

ABSTRACT

This study focused on characterizing sewage sludge, food waste, and livestock manure, representative of continuously generated organic wastes, along with their anaerobic digestion residues. Microwave assisted pyrolysis was employed to investigate the relationship between the properties of the raw organic wastes and the resulting pyrolysis products, utilizing the R-program for analysis. Evaluation of the pyrolysis products of these six organic wastes revealed that char yield was primarily influenced by ash and fixed carbon contents, with higher yields observed in residues from anaerobic digestion compared to the original organic waste. Liquid and gaseous product quantities were found to increase with volatile content, while high-fat content within the volatile fraction notably enhanced liquid product yields, impacting syngas production. Analysis of syngas composition indicated a negative correlation between high nitrogen content in the feedstock and H2 generation. Furthermore, examining the correlation between chemical properties of organic waste and pyrolysis products revealed a proportional increase in protein components with nitrogen content, suggesting potential improvements in pyrolysis efficiency through raw material pretreatment enhancements by the R program.

2.
Chemosphere ; 357: 142007, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38631497

ABSTRACT

For energy recovery, anaerobic digestion is applied to organic waste, such as livestock manure (LM) and food wastewater (FW). Digested sludge(DS), a residue from the anaerobic co-digestion of LM and FW, is another type of organic waste that can be converted into energy through pyrolysis. This study compared the pyrolysis characteristics of LM, FW, and DS. The product content varied with the pyrolysis temperature, rate of temperature increase, reaction time, and final reaction temperature. Gas production from FW and DS was similar; however, gas production from LM was low. As the pyrolysis temperature increased, the H2 content increased, and the CO2 content decreased, respectively. At 1000 °C, the H2 content of LM increased to 45%, and FW produced the most gas but the lowest H2 content. The H2/CO ratios of LM and FW ranged from 3.5 to 5.2, while those of DS ranged from 5.5 to 12.4, with the highest values. The carbon conversion rate was the highest for the gaseous products of LM (30-54%) and lowest for the gaseous products of digested sludge (26-36%). Conversely, the cold gas efficiency was the highest for the DS and lowest for the LM. Following anaerobic digestion, the DS generated less tar than the untreated LM and FW, showed higher efficiency in gas generation and gas properties, and exhibited a higher value as a char fuel.


Subject(s)
Livestock , Manure , Pyrolysis , Sewage , Waste Disposal, Fluid , Wastewater , Manure/analysis , Sewage/chemistry , Animals , Wastewater/chemistry , Anaerobiosis , Waste Disposal, Fluid/methods , Gases/analysis , Gases/chemistry
3.
J Hazard Mater ; 468: 133762, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38402678

ABSTRACT

Assessing the cyanobacteria disinfection in sewage and its compliance with international-standards requires determining the concentration and viability, which can be achieve using Imaging Flow Cytometry device called FlowCAM. The objective is to thoroughly investigate the sonolytic morphological changes and disinfection-performance towards toxic cyanobacteria existing in sewage using the FlowCAM. After optimizing the process conditions, over 80% decline in cyanobacterial cell counts was observed, accompanied by an additional 10-15% of cells exhibiting injuries, as confirmed through morphological investigation. Moreover, for the first time, the experimentally collected data was utilized to build deep-learning probabilistic-neural-networks (PNN) and natural-gradient-boosting (NGBoost) models for predicting disinfection efficiency and ABD area as target outputs. The findings suggest that the NGBoost model exhibited superior prediction performance for both targets, with high test coefficient of determination (R2 > 0.87) and lower test errors (RMSE < 7.10, MAE < 4.14). The confidence interval examination in NGBoost prediction performance showed a minute variation from the experimentally calculated values, suggesting a high accuracy in model prediction. Finally, SHAP analysis suggests the sonolytic time alone contributes around 50% to the cyanobacteria disinfection. Overall, the findings demonstrate the effectiveness of the FlowCAM device and the potential of machine-learning modeling in predicting disinfection outcomes.


Subject(s)
Cyanobacteria , Wastewater , Disinfection , Sewage , Machine Learning
4.
Arch Craniofac Surg ; 24(5): 218-222, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37919908

ABSTRACT

BACKGROUND: Botulinum toxin is a neurotoxic substance with a wide range of uses, from the treatment of musculoskeletal spasms to antiaging regimens by improving wrinkles. Split-face studies in which drugs are injected in the right and left sides of the faces have been actively conducted in botulinum toxin studies. In this study, we aimed to investigate the reliability of a split-face study for determining the effectiveness of botulinum toxin based on eyebrow height and movement, and electromyography results. METHODS: Thirty-one women aged 35 to 55 years were included in the study. Eyebrow height was measured as the distance from the eyebrows to the upper eyelid margin on the primary gaze, and eyebrow movement was measured as the distance when the forehead was wrinkled for 5 seconds. A noninvasive method was used for electromyography of the frontalis muscles. RESULTS: No statistically significant differences in right and left eyebrow heights and movements, and electromyography findings (p= 0.256, p= 1.000, and p= 0.978, respectively) were found. Pearson correlation analysis showed that electromyography muscle activity is positively associated with eyebrow movement, respectively (p< 0.001). CONCLUSION: We advocate the reliability of split-face study and the usefulness of electromyography of frontalis muscle in forehead rejuvenation research.

5.
Chemosphere ; 332: 138881, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37164203

ABSTRACT

Zinc smelting wastewater contains high concentrations of Cd. Here, the treatment efficiency of Cd using electrodialysis was evaluated. In addition, scale accumulation of ion-exchange membrane (IEM) was analyzed, and fouling control was studied. The results showed that spacers effectively improved the limiting current density but accelerated foulant accumulation. The Cd-treatment efficiency improved to 85.4% without a spacer. Dissolved organic carbon (DOC) and hydrophobic DOC levels in diluted water decreased by 0.65 mg L-1 and 2.1 mg L-1, respectively; in contrast, hydrophilic DOC level increased by 1.45 mg L-1. Some of the hydrophobic DOC in the diluted water was converted to hydrophilic DOC and subsequently to low-molecular-weight (LMW) DOC. DOC level in the concentrated water did not change substantially, but the LMW fraction of the hydrophilic DOC increased. In the cation-exchange membrane, a material composed of calcium sulfate accumulated in the bottom layer, and hydroxides of divalent and trivalent ions accumulated on top of it. In contrast, the anion-exchange membrane was fouled by humic substances. In terms of fouling control, physical and acid cleaning of IEMs was more effective than the reversal operation.


Subject(s)
Wastewater , Water Purification , Cadmium , Zinc , Organic Chemicals/chemistry , Water , Membranes, Artificial , Water Purification/methods
6.
Heliyon ; 9(3): e14165, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36923894

ABSTRACT

In this study, the pyrolysis of sewage sludge was explored through microwave-assisted pyrolysis. Three kinds of sludge (primary sludge, waste-activated sludge, and digested sludge) from a sewage treatment process were used. All three kinds of sewage sludge had a low microwave absorption capacity; therefore, an absorber was added to enable microwave-assisted pyrolysis. By using silicon carbide as the heating element, it was possible to increase the temperature within a short time by applying microwaves. During the microwave-assisted pyrolysis of sewage sludges, the amount of gas generated and the H2 and CO fraction of the produced gas increased as temperature increased. The pyrolysis of waste-activated sludge produced the greatest quantity of gas. However, the primary sludge produced the highest amount of syngas in terms of H2 and CO, which indicate the high-quality of the syngas.

7.
Taehan Yongsang Uihakhoe Chi ; 83(3): 724-729, 2022 May.
Article in English | MEDLINE | ID: mdl-36238499

ABSTRACT

A duodenal web is an incomplete diaphragm of the duodenal lumen that causes a partial or (intermittent) complete obstruction. The size of a duodenal web's aperture determines the degree of obstruction, age at presentation, and radiologic findings. We report a case of duodenal web incidentally diagnosed in a 14-month-old boy who presented to the hospital after ingesting a foreign body. We provide a comprehensive report of multiple studies through abdominal radiograph, upper gastrointestinal study, endoscopy, and surgical findings. We emphasize that the duodenum should be considered as the location of the obstruction when infants exhibit delayed discharge or dynamic positioning of a foreign body in a radiologic examination.

8.
Plants (Basel) ; 11(9)2022 Apr 29.
Article in English | MEDLINE | ID: mdl-35567213

ABSTRACT

Perilla, also termed as purple mint, Chinese basil, or Perilla mint, is a flavoring herb widely used in East Asia. Both crude oil and essential oil are employed for consumption as well as industrial purposes. Fatty acids (FAs) biosynthesis and oil body assemblies in Perilla have been extensively investigated over the last three decades. Recent advances have been made in order to reveal the enzymes involved in the fatty acid biosynthesis in Perilla. Among those fatty acids, alpha-linolenic acid retained the attention of scientists mainly due to its medicinal and nutraceutical properties. Lipids synthesis in Perilla exhibited similarities with Arabidopsis thaliana lipids' pathway. The homologous coding genes for polyunsaturated fatty acid desaturases, transcription factors, and major acyl-related enzymes have been found in Perilla via de novo transcriptome profiling, genome-wide association study, and in silico whole-genome screening. The identified genes covered de novo fatty acid synthesis, acyl-CoA dependent Kennedy pathway, acyl-CoA independent pathway, Triacylglycerols (TAGs) assembly, and acyl editing of phosphatidylcholine. In addition to the enzymes, transcription factors including WRINKLED, FUSCA3, LEAFY COTYLEDON1, and ABSCISIC ACID INSENSITIVE3 have been suggested. Meanwhile, the epigenome aspect impacting the transcriptional regulation of FAs is still unclear and might require more attention from the scientific community. This review mainly outlines the identification of the key gene master players involved in Perilla FAs biosynthesis and TAGs assembly that have been identified in recent years. With the recent advances in genomics resources regarding this orphan crop, we provided an updated overview of the recent contributions into the comprehension of the genetic background of fatty acid biosynthesis. The provided resources can be useful for further usage in oil-bioengineering and the design of alpha-linolenic acid-boosted Perilla genotypes in the future.

9.
Chemosphere ; 301: 134791, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35508263

ABSTRACT

In this study, an open pond constructed in Myanmar, a region with tropical climate and favorable environmental conditions for algae growth, was considered to conduct field experiments on sewage inflow river water. The nutrient removal efficiency and productivity of Hydrodictyon reticulatum (H. reticulatum) were analyzed, and the maximum fermentation limit concentration for bioethanol production was determined. Three ponds were operated in batch mode to investigate the effect of light intensity. Photoinhibition was caused due to excessive light intensity in summer season in the region with tropical climate resulting in reduced facility efficiency in the absence of shade. For light blocking, a transparent film was found to be more effective than a translucent film. In the transparent film shading facility, the nitrogen and phosphorus removal efficiencies were maintained above 76% and 81%, respectively, and the productivity of H. reticulatum was 2.27 g m-2 d-1. For a raceway open pond facility shaded with transparent film, the performance was evaluated based on hydraulic retention time (HRT), and the productivity of algae was found to increase with increasing supply of nitrogen and phosphorous. Maximum biomass production of 3.21 g m-2 d-1 was observed with an HRT of 3 d, suggesting the possibility of long-term operation. As a result of evaluating the ethanol production based on the initial concentration of H. reticulatum, the yield of bioethanol at the initial reducing sugar content of 120 g L-1 was 89.4%, but bioethanol production was only 8.9 g L-1.


Subject(s)
Microalgae , Water Purification , Biomass , Nitrogen , Nutrients , Phosphorus , Ponds , Waste Disposal, Fluid/methods , Wastewater , Water , Water Purification/methods
10.
Chemosphere ; 277: 130129, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33774229

ABSTRACT

Although microalgae are seen as a potential alternative source of energy and other materials currently sourced from petroleum, issues still remain with industrialization because of difficulties in developing commercially operational microalgal production systems. We set up a pilot-scale study that involved the simultaneous reuse of wastewater and production of algae under different light and harvesting conditions. We cultivated Hydrodictyon reticulatum (H. reticulatum), a type of water-net algae, using secondary effluent from a wastewater treatment plant in a raceway open pond combined with an underwater light device. Experimental results showed that the underwater light device maintained some level of underwater light throughout the year. Photoinhibition of algal growth only occurred when the sunlight exceeded 1270 µmol m-2 s-1. During the non-harvest process, the maximum algal concentration was 1700 mg L-1 at 20 days after the experiment began, the maximum specific growth rate was 0.18 d-1 and the maximum productivity was 21.3 g m-2 d-1. Conversely, periodic harvesting decreased the concentration of nutrients in the effluent more as the days of cultivation increased, but the productivity of algae also decreased to 11.7 g m-2 d-1. The maximum yield of bioethanol using three kinds of fermentation strains was 93.5% and, thus, the commercial value of H. reticulatum as a raw material for energy production was excellent.


Subject(s)
Microalgae , Ponds , Biofuels , Biomass , Nutrients , Wastewater , Water
11.
Environ Sci Pollut Res Int ; 28(30): 40703-40714, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33547611

ABSTRACT

Although the struvite crystallization process has proven to be an effective process for the recovery of nutrients from wastewater, this process has not been widely used due to the excessive use of chemicals. In this study, the optimal production conditions, yield, and economic feasibility of struvite using the anaerobic digestion of livestock wastewater were investigated. In addition, the economic feasibility of adding zeolite to improve the productivity of struvite and additionally remove nitrogen was evaluated. The result of the experiment on the struvite yield change according to the molar ratios at pH 9.0 showed that the struvite yield ratio was 99.0% of the stoichiometric yield at the Mg2+ :NH4+ :PO43- molar ratios of 1.2:1.0:1.1. As a magnesium source, MgCl2, concentrated seawater in the seawater desalination process, and MgO were compared, and when MgO was used, struvite productivity and economic efficiency were the best. Also, while the addition of zeolite greatly increased the struvite production and zeolite was also sold as a soil conditioner, the struvite sales benefit was estimated to be 103% of the operating cost.


Subject(s)
Magnesium Compounds , Phosphorus , Anaerobiosis , Animals , Feasibility Studies , Phosphates , Struvite , Waste Disposal, Fluid , Wastewater
12.
J Hosp Palliat Care ; 24(4): 235-244, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-37674638

ABSTRACT

Purpose: This study aimed to provide basic data for developing interventions to relieve the end-of-life care stress experienced by pediatric nurses by examining the relationships of end-of-life care stress with compassionate competence and attitudes toward end-of-life care. Methods: Data were collected via a survey that was conducted from September 10 to September 30, 2018 and administered to 113 nurses who had worked for more than 6 months in a pediatric unit at a tertiary hospital in Seoul, South Korea. The data were analyzed for frequency, percentage, mean, and standard deviation, and the independent t-test, one-way analysis of variance, and Pearson correlation analysis were conducted using SPSS version 25.0. Results: End-of-life care stress among pediatric nurses had a weak positive correlation (r=0.216, P<0.05) with compassionate competence and had no significant correlation with attitudes toward end-of-life care. Among the sub-factors of end-of-life care stress, psychological difficulties had a weak positive correlation with sensitivity (r=0.309, P<0.01) and communication (r=0.230, P<0.05), which are aspects of compassionate competence. Lack of knowledge about end-of-life care had a weak positive correlation with communication (r=0.209, P<0.05) as an aspect of compassionate competence. Conclusion: To improve the quality of end-of-life care provided by pediatric nurses, it is necessary to improve their compassionate competence and reduce their end-of-life care stress by developing education and support programs tailored to the characteristics of children and specific communication methods.

13.
Sci Total Environ ; 757: 143762, 2021 Feb 25.
Article in English | MEDLINE | ID: mdl-33316530

ABSTRACT

Recent development in industry has led to increased water usage, while intensifying water shortage. Electrodialysis has been proposed as a technique for minimizing the generation of secondary environmental pollution problems and effectively treating harmful substances such as heavy metals in industrial wastewater. As electrodialysis is affected by several factors, it is crucial to provide necessary information about the operating elements. This study investigates the effect of linear flow velocity on the removal of heavy metals in an electrodialysis pilot plant. The results of the experiment showed that increasing the linear flow velocity from 0.6 to 5.1 cm/min increased the voltage from 17.3 to 40 V. In addition, the limiting current density (LCD) showed a linear relationship with the linear flow velocity, increasing from 1.4 to 5.9 A/m2 as the linear flow velocity increased proportionally in the same voltage range. The empirical correlation coefficients a and b for the mass transfer coefficient K, which can be expressed as a nonlinear function of the linear flow velocity, were estimated to be 1.8519 and 0.7016, respectively. In the batch operation, the ion-separation rate in the electrodialysis process was estimated with the shift order kinetics of the first-order and zero-order constants via regression analysis of experimental data. The ion separation rate in the diluate and the ion concentration rate in the concentrate decrease as the experiment number increase. This may be due to the reverse diffusion of ions transferring to the diluate owing to the high concentration of ions in the concentrate. Therefore, ion concentration in the concentrate has to be maintained at an appropriate level. Copper ions are deposited on the cathode electrode surface, although not uniformly.

14.
Environ Pollut ; 269: 116127, 2021 Jan 15.
Article in English | MEDLINE | ID: mdl-33279266

ABSTRACT

In this study, heavy metal-containing sunflower residues obtained from a phytoremediation site were hydrothermally carbonized at 160-260 °C. The properties of hydrochar thus produced were evaluated with respect to its potential as solid fuel. The results confirmed that hydrothermal carbonization (HTC) reduced the concentration of heavy metals in hydrochars, with the concentration lower than the maximum permissible level of domestic standards for bio-solid refuse fuel. Higher HTC temperatures resulted in improved energy-related properties of the hydrochar (i.e., coalification degree, fuel ratio, and higher heating value); however, HTC temperatures between 200 and 220 °C were deemed suitable for energy retention efficiency. Furthermore, as hydrochar contains low nitrogen and ash content, it can be considered as a clean energy source. The results of this study suggest a sustainable approach to the disposal and effective utilization of contaminant-containing biowastes. Moreover, this study suggests linking biomass cultivation for phytoremediation and converting the phytoremediated biomass into value-added solid fuel.


Subject(s)
Carbon , Metals, Heavy , Biodegradation, Environmental , Biomass , Temperature
15.
Chemosphere ; 256: 127116, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32460161

ABSTRACT

Anaerobic digestion (AD) of lignocellulosic biomass is appealing because of the abundance and ease of obtaining the biomass locally. However, the recalcitrance of lignocellulosic biomass presents an obstacle in the hydrolysis step of AD and lowers the process efficiency. In this study, sunflower, which is a model lignocellulosic biomass, was pretreated by thermal (hydrothermal pretreatment, HTP) and non-thermal (milling) methods; the methane yield and biodegradability of the pretreated biomass were determined using a series of batch tests. The thermal pretreatment method showed a significantly higher methane yield (213.87-289.47 mL g-1 VS) and biodegradability (43-63%) than those of the non-thermally pretreated biomass, and the optimum pretreatment effect was observed at an HTP temperature of 180 °C. However, at an HTP temperature exceeding 200 °C, the induced formation of 5-hydroxymethylfurfural and furfural significantly lowered the methane yield and biodegradability. This study revealed that the HTP temperature is closely related to the formation of lignocellulosic biomass-degrading byproducts, which potentially hinder the methanogenesis step in AD; severe HTP conditions may have the opposite effect on the AD performance of lignocellulosic biomass.


Subject(s)
Biofuels/analysis , Hot Temperature , Lignin/chemistry , Methane/analysis , Refuse Disposal/methods , Anaerobiosis , Biodegradation, Environmental , Biomass , Hydrolysis
16.
Bioresour Technol ; 303: 122934, 2020 May.
Article in English | MEDLINE | ID: mdl-32036325

ABSTRACT

In this study, leather fleshing waste (LFW) and a complementary substrate (food waste leachate; FWL) were co-digested. The main focus of research was to study effects on biogas production caused by interactions between co-substrates when combined in different mixing ratios and changes on microbial community structures. Due to a positive effect of co-digestion (i.e., establishing nutrient equilibrium), the adjusted substrates for optimum C/N ratio by blending LFW and FWL resulted in significantly higher biodegradability and biomethane production (375.5-520.8 mL CH4 g-1 VS) than the mono-digestion of each substrate. According to co-digestion of LFW and FWL, microbial communities became more diverse and the changes of microbial structure influenced the biomethane production performance. Among the co-digesting conditions, the biomethane production yield and rate of the samples were in reverse order and the results were firmly associated with the relative richness of lipids (yield-related) and proteins (rate-related) in the co-substrates.


Subject(s)
Microbiota , Refuse Disposal , Anaerobiosis , Biofuels , Bioreactors , Food , Methane
17.
J Environ Manage ; 247: 115-120, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31234046

ABSTRACT

This study presents hydrothermal carbonization (HTC) of leather waste (LW) to produce hydrochar and feasibility of using produced hydrochar as solid fuel. The results showed that a relatively low HTC treatment temperature (180-200 °C) improved both the hydrochar product yield (>82.9% by dry weight) and its potential use as a solid fuel with in terms of its physicochemical properties and heating value. Furthermore, the hydrochar showed a higher heating value (5807-6508 kcal kg-1) compared to that of low-ranked coals (i.e., sub-bituminous and lignite), and stable combustion characteristics at a higher temperature. This allows the hydrochar to be considered as a suitable alternative to conventional fossil fuel. In addition, the decrease of nitrogen content in the hydrochar during the HTC treatment, and the inherent low sulfur content of LW could make hydrochar a more appealing clean energy source. The findings of this study suggest that the conversion of LW through HTC can be a useful method for waste management and energy recovery from abandoned biomass.


Subject(s)
Carbon , Coal , Biomass , Feasibility Studies , Temperature
18.
Environ Sci Pollut Res Int ; 26(33): 34332-34344, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31175569

ABSTRACT

Struvite precipitation is an effective method to remove and recover ammonia and phosphate from livestock wastewater. Struvite has properties similar to those of the traditional ammonium-phosphate fertilizer, which does not burn the roots owing to its slow-release characteristics. Struvite is an effective fertilizer as its nutrient-releasing rate is very slow. But the release rate of ammonia and phosphate in soil depends on the size of crystals. In this study, the nutrient-releasing pattern of three types of struvite crystals and liquid fertilizer was compared using soil column. X-Ray fluorescence spectrometry was conducted to investigate the potential use of struvite as a fertilizer. Various struvite crystalline fertilizers were evaluated for their fertilizer performance by cultivating potted vegetable crops. The nitrogen removal efficiency of zeolite-seeded struvite was higher than that of no seed struvite. The ammonia nitrogen removal efficiency was more than 99% irrespective of the kind of zeolite. The soil column test revealed that nutrient releasing from liquid fertilizer and zeolite-seeded struvite recovered from livestock wastewater was 11 and 63 days, respectively. Struvite recovered from livestock wastewater contained more than 20% (w/w) potassium oxide; however, the concentration of heavy metals, such as copper and zinc, was very low. Therefore, we considered that the synthesized struvite using livestock wastewater has high value as fertilizer. The recovered struvite was effective under appropriate concentrations to cultivate all the applied vegetable crops in this study.


Subject(s)
Fertilizers/analysis , Struvite/chemistry , Vegetables/growth & development , Ammonia/analysis , Metals, Heavy/analysis , Nitrogen/analysis , Nutrients , Phosphates/chemistry , Phosphorus , Soil , Wastewater/chemistry
19.
Chemosphere ; 230: 157-163, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31103861

ABSTRACT

This study presents co-hydrothermal treatment of primary sludge (PS) from wastewater treatment plant (WWTP) and Chlorella sp., cultivated using WWTP effluent, and feasibility of using produced hydrochar as solid fuel. The results showed that properties of PS were improved through blending with Chlorella sp., in terms of mixture hydrochar properties (physicochemical composition, calorific value, fuel ratio, product yield, and energy recovery potential). The coalification degree (1.63 of H/C and 0.41 of O/C) and calorific value (5810 kcal kg-1) of hydrochar at 210 °C, defined as suitable hydrothermal carbonization temperature for mixture hydrochar production, were comparable to those of low-ranked coals (i.e., sub-bituminous and lignite). The low ash (<16.01% by dry weight until treatment temperature of 210 °C) and sulfur (0.64-0.78% by dry weight for all treatment temperature) contents of mixture hydrochar make it more attractive solid fuel as clean energy source. The findings suggest that the co-hydrothermal treatment of biomass (generated sludge and cultivated microalgae from WWTP) helps energy self-sufficiency in municipal WWTP.


Subject(s)
Biofuels , Chlorella/physiology , Waste Disposal, Fluid , Biomass , Carbon/chemistry , Coal , Microalgae , Sewage , Temperature , Wastewater/chemistry
20.
Environ Pollut ; 243(Pt B): 1704-1709, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30408857

ABSTRACT

It is desirable to establish an environmentally benign platform for disposing biomass from the phytoremediation process while recovering energy is of importance. To this end, the biochemical methane potential (BMP) tests were conducted using four different biomass samples (i.e., sunflower: Helianthus annuus) that were obtained from the different remediation sites. In particular, this study laid great emphasis on evaluating the inhibition for the anaerobic digestion (AD) process induced by endogenous heavy metal (Cd, Cu, Ni, Pb, and Zn) content in biomass. Despite the high levels of heavy metal contents (Cd: 58.4, Cu: 23.0, Ni: 2.01, Pb: 9.88, and Zn: 146 mg kg-1) in the substrate for the AD process, the overall performance was comparable relative to the case of the references. Therefore, this study signified that the inhibition derived from heavy metals was nearly negligible, which suggested that biomass from the phytoremediation site could be used as a substrate for the AD process.


Subject(s)
Biodegradation, Environmental , Helianthus/metabolism , Metals, Heavy/analysis , Metals, Heavy/metabolism , Methane/biosynthesis , Soil Pollutants/analysis , Soil Pollutants/metabolism , Biomass , Environmental Restoration and Remediation
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