| 1. |
- Forgács, Gergely, 1983, et al.
(författare)
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Biological treatment of chicken feather waste for improved biogas production
- 2011
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Ingår i: Journal of Environmental Sciences. - : Elsevier BV. - 1001-0742 .- 1878-7320. ; 23:10, s. 1747-1753
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Tidskriftsartikel (refereegranskat)abstract
- A two-stage system was developed which combines the biological degradation of keratin-rich waste with the production of biogas. Chicken feather waste was treated biologically with a recombinant Bacillus megaterium strain showing keratinase activity prior to biogas production. Chopped, autoclaved chicken feathers (4%, W/V) were completely degraded, resulting in a yellowish fermentation broth with a level of 0.51 mg/mL soluble proteins after 8 days of cultivation of the recombinant strain. During the subsequent anaerobic batch digestion experiments, methane production of 0.35 Nm(3)/kg dry feathers (i.e., 0.4 Nm(3)/kg volatile solids of feathers), corresponding to 80% of the theoretical value on proteins, was achieved from the feather hydrolyzates, independently of the pre-hydrolysis time period of 1, 2 or 8 days. Cultivation with a native keratinase producing strain, Bacillus licheniformis resulted in only 0.25 mg/mL soluble proteins in the feather hydrolyzate, which then was digested achieving a maximum accumulated methane production of 0.31 Nm(3)/kg dry feathers. Feather hydrolyzates treated with the wild type B. megaterium produced 0.21 Nm(3) CH(4)/kg dry feathers as maximum yield.
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| 2. |
- Yang, Weijin, et al.
(författare)
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Alterations of endogenous metabolites in urine of rats exposed to decabromodiphenyl ether using metabonomic approaches
- 2014
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Ingår i: Journal of Environmental Sciences(China). - : Elsevier. - 1001-0742 .- 1878-7320. ; 26:4, s. 900-908
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Tidskriftsartikel (refereegranskat)abstract
- There is large usage of polybrominated diphenyl ethers (PBDEs) especially for decabromodiphenyl ether (BDE-209, Deca-BDE) in controlling the risks of fire. The toxicological effects of PBDEs are worth being concerned about. Female SD rats were daily gavaged with BDE-209 ether at the dose of 100 mg/kg for 20 days. Histological observation was performed for the screening of the target organs for BDE-209 exposure. The distribution and metabolism of PBDEs in the exposed main organs were evidenced by HRGC-HRMS. Alterations of the endogenous metabolite concentrations in urine were investigated using metabonomic approaches based on (1)H NMR spectrum. Histopathological changes including serious edema in kidney, hepatocellular spotty necrosis and perivasculitis in liver indicated that BDE-209 caused potential influences on endogenous metabolism in the exposed liver and the kidney. BDE-209 was found to be highly accumulated in lipid, ovary, kidney and liver after 20 days' exposure. Occurrence of other lower brominated PBDEs in the rats demonstrated that reductive debromination process happened in vivo. Hydroxylated and methoxylated-BDEs, as metabolism products, were also detected in the rat tissues. A total of 12 different endogenous metabolites showed obvious alterations in urine from the exposed rats, indicating the disturbance of the corresponding internal biochemical processes induced by BDE-209 exposure. These findings in vivo suggested the potential health risk might be of concern due to the toxicological effects of BDE-209 as a ubiquitous compound in the environment.
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| 3. |
- Wang, Zengzhang, et al.
(författare)
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Management of process performance at low water temperatures in respect of filamentous organisms
- 2004
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Ingår i: Journal of Environmental Sciences(China). - 1001-0742 .- 1878-7320. ; 16:1, s. 113-116
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Tidskriftsartikel (refereegranskat)abstract
- The management of sludge-settling properties in Nordic conditions is of importance during the low temperature (spring) season because of the peak settler load. A survey was made in 10 Finnish waste water treatment plants(WWTP's) and the total extended filament length and DSVI in half of the plants exceeded the limits, which indicates sludge bulking(15 km/g SS and 150 ml/g respectively). The dominant organism was Microthrix parvicella, the abundance of which was 59.22% of total extended filament length on average. Chemicals were tested to control the filaments, and it was found that special attention has to be paid to maintaining the nitrification at low temperature. A dosage of(H2O2-based) oxidants controlled the growth of Microthrix parvicella effectively and rapidly, whereas with the use of aluminium hydroxidechloride a 2 to 5-week period was needed to decrease the filament length.
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| 4. |
- Eriksson, Ulrika, 1972-, et al.
(författare)
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Contribution of precursor compounds to the release of per- and polyfluoroalkyl substances (PFASs) from waste water treatment plants (WWTPs)
- 2017
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Ingår i: Journal of Environmental Sciences(China). - : SCIENCE PRESS. - 1001-0742 .- 1878-7320. ; 61, s. 80-90
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Tidskriftsartikel (refereegranskat)abstract
- Per- and polyfluoroalkyl substances (PFASs) are ubiquitous in sludge and water from waste water treatment plants, as a result of their incorporation in everyday products and industrial processes. In this study, we measured several classes of persistent PFASs, precursors, transformation intermediates, and newly identified PFASs in influent and effluent sewage water and sludge from three municipal waste water treatment plants in Sweden, sampled in 2015. For sludge, samples from 2012 and 2014 were analyzed as well. Levels of precursors in sludge exceeded those of perfluoroalkyl acids and sulfonic acids (PFCAs and PFSAs), in 2015 the sum of polyfluoroalkyl phosphoric acid esters (PAPs) were 15-20 ng/g dry weight, the sum of fluorotelomer sulfonic acids (FTSAs) was 0.8-1.3 ng/g, and the sum of perfluorooctane sulfonamides and ethanols ranged from non-detected to 3.2 ng/g. Persistent PFSAs and PFCAs were detected at 1.9-3.9 ng/g and 2.4-7.3 ng/g dry weight, respectively. The influence of precursor compounds was further demonstrated by an observed substantial increase for a majority of the persistent PFCAs and PFSAs in water after waste water treatment. Perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), and perfluorooctane sulfonic acid (PFOS) had a net mass increase in all WWTPs, with mean values of 83%, 28%, 37% and 58%, respectively. The load of precursors and intermediates in influent water and sludge combined with net mass increase support the hypothesis that degradation of precursor compounds is a significant contributor to PFAS contamination in the environment. (C) 2017 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.
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| 5. |
- González-Arias, Judith, et al.
(författare)
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Hydrochar and synthetic natural gas co-production for a full circular economy implementation via hydrothermal carbonization and methanation: An economic approach
- 2024
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Ingår i: Journal of Environmental Sciences. - 1001-0742 .- 1878-7320. ; 140, s. 69-78
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Tidskriftsartikel (refereegranskat)abstract
- Herein we study the economic performance of hydrochar and synthetic natural gas co-production from olive tree pruning. The process entails a combination of hydrothermal carbonization and methanation. In a previous work, we evidenced that standalone hydrochar production via HTC results unprofitable. Hence, we propose a step forward on the process design by implementing a methanation, adding value to the gas effluent in an attempt to boost the overall process techno-economic aspects. Three different plant capacities were analyzed (312.5, 625 and 1250 kg/hr). The baseline scenarios showed that, under the current circumstances, our circular economy strategy in unprofitable. An analysis of the revenues shows that hydrochar selling price have a high impact on NPV and subsidies for renewable coal production could help to boost the profitability of the process. On the contrary, the analysis for natural gas prices reveals that prices 8 times higher than the current ones in Spain must be achieved to reach profitability. This seems unlikely even under the presence of a strong subsidy scheme. The costs analysis suggests that a remarkable electricity cost reduction or electricity consumption of the HTC stage could be a potential strategy to reach profitability scenarios. Furthermore, significant reduction of green hydrogen production costs is deemed instrumental to improve the economic performance of the process. These results show the formidable techno-economic challenge that our society faces in the path towards circular economy societies.
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| 6. |
- Gu, Zhenhong, et al.
(författare)
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Analysis of the most widely used building environmental assessment methods
- 2006
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Ingår i: Journal of Environmental Sciences(China). - : Informa UK Limited. - 1001-0742 .- 1878-7320. ; 3:3, s. 175-192
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Tidskriftsartikel (refereegranskat)abstract
- Building Environmental Assessment (BEA) is a term used for several methods for environmental assessment of the building environment. Generally, Life Cycle Assessment (LCA) is an important foundation and part of the BEA method, but current BEA methods form more comprehensive tools than LCA. Indicators and weight assignments are the two most important factors characterizing BEA. From the comparison of the three most widely used BEA methods, EcoHomes (BREEAM for residential buildings), LEED-NC and GBTool, it can be seen that BEA methods are shifting from ecological, indicator-based scientific systems to more integrated systems covering ecological, social and economic categories. Being relatively new methods, current BEA systems are far from perfect and are under continuous development. The further development of BEA methods will focus more on non-ecological indicators and how to promote implementation. Most BEA methods are developed based on regional regulations and LCA methods, but they do not attempt to replace these regulations. On the contrary, they try to extend implementation by incentive programmes. There are several ways to enhance BEA in the future: expand the studied scope from design levels to whole life-cycle levels of constructions, enhance international cooperation, accelerate legislation and standardize and develop user-oriented assessment systems.
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| 7. |
- Kanbar, Hussein Jaafar, et al.
(författare)
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Selective metal leaching from technosols based on synthetic root exudate composition
- 2020
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Ingår i: Journal of Environmental Sciences(China). - : Science Press. - 1001-0742 .- 1878-7320. ; 96, s. 85-92
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Tidskriftsartikel (refereegranskat)abstract
- This study focused on metal release from technosols induced by synthetic root exudate (SRE). The effect of SRE composition on metal release was studied using six technosols. This was done by treating the technosols with SRE solutions having varying concentrations of low molecular weight organic acids (LMWOAs), namely oxalic, citric, and malic acids. Consequently, the physico-chemical parameters (pH and electric conductivity), Ca, Mg, Fe, Zn, and Cu release (by atomic absorption spectroscopy, AAS), chemical changes (by Fourier transform infrared, FT-IR), and organic parameters (by fluorescence) were investigated. Metal release showed to be dependent on the SRE composition and technosol characteristics. Citric acid selectively released Ca, Mg, Zn, and Cu from technosols in a concentration-dependent manner; oxalic acid showed a significant role in the release of Mg and Fe. Under relatively high LMWOA concentrations, particulate organo- mineral complexes precipitated. Additionally, technosol weathering was seen by the dissolution of humic substances and ferriallophanes, which in turn caused metal release. However, re-precipitation of these phases showed to re-sorb metals, thus underestimating the role of LMWOAs in metal release. Therefore, the selective metal leaching was highly dependent on the SRE composition and LMWOA concentrations on one hand, and on the mineral, organic, and organo-mineral components of the technosols on the other. The understanding of such processes is crucial for proposing and implementing environmental management strategies to reduce metal leaching or for the beneficial re-usage of metals (e.g., for agromining) from technosols. (C) 2020 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.
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| 8. |
- Lu, Xiaotian, et al.
(författare)
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Climate change induced eutrophication of cold-water lake in an ecologically fragile nature reserve
- 2019
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Ingår i: Journal of Environmental Sciences (China). - : Elsevier BV. - 1001-0742 .- 1878-7320. ; 75, s. 359-369
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 Aquatic ecosystem sustainability around the globe is facing crucial challenges because of increasing anthropogenic and natural disturbances. In this study, the Tianchi Lake, a typical cold-water lake and a UNESCO/MAB (Man and Biosphere) nature reserve located in high latitude and elevation with the relatively low intensity of human activity was chosen as a system to examine the linkages between climate change and eutrophication. As a part of the UNESCO Bogda Man and Biosphere Reserve, Tianchi Lake has been well preserved for prevention from human intervention, but why has it been infected with eutrophication recent years? Our results show that climate change played a significant role in the eutrophication in the Tianchi Lake. Increased temperature, changed precipitation pattern and wind-induced hydrodynamic fluctuations in the summer season were suggested to make a major contribution to the accelerated eutrophication. The results also showed that the local temperature and precipitation changes were closely linked to the large-scale atmospheric circulation, which opens the door for the method to be applied in other regions without local climatic information. This study suggests that there is an urgent need to take into consideration of climate change adaptation into the conservation and management of cold-water lakes globally.
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| 9. |
- Meng, Qingpeng, et al.
(författare)
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Zeolite A synthesized from alkaline assisted pre-activated halloysite for efficient heavy metal removal in polluted river water and industrial wastewater
- 2017
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Ingår i: Journal of Environmental Sciences(China). - : Elsevier BV. - 1001-0742 .- 1878-7320. ; 56, s. 254-262
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Tidskriftsartikel (refereegranskat)abstract
- High quality zeolite A was synthesized through a hydrothermal process using alkaline-assisted pre-activated halloysite mineral as the alumina and silica source. The synthesis conditions employed in this study were finely tuned by varying the activating temperature, sodium hydroxide content, water content and Si/Al ratio. The obtained zeolite A showed excellent adsorption properties for both single metal cation solutions and mixed cation solutions when the concentrations of the mixed cations were comparable with those in polluted natural river water and industrial wastewater. High adsorptive capacities for Ag+ (123.05 mg/g) and Pb2+ (227.70 mg/g) were achieved using the synthesized zeolite A. This observation indicates that the zeolite A synthesized from alkaline-assisted pre-activated halloysite can be used as a low-cost and relatively effective adsorbent to purify heavy metal cation polluted natural river water and industrial wastewater.
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| 10. |
- Morin, Nicolas A. O., et al.
(författare)
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The presence and partitioning behavior of flame retardants in waste, leachate, and air particles from Norwegian waste-handling facilities
- 2017
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Ingår i: Journal of Environmental Sciences(China). - : Science Press. - 1001-0742 .- 1878-7320. ; 62, s. 115-132
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Tidskriftsartikel (refereegranskat)abstract
- Flame retardants in commercial products eventually make their way into the waste stream. Herein the presence of flame retardants in Norwegian landfills, incineration facilities and recycling sorting/defragmenting facilities is investigated. These facilities handled waste electrical and electronic equipment (WEEE), vehicles, digestate, glass, combustibles, bottom ash and fly ash. The flame retardants considered included polybrominated diphenyl ethers (∑ BDE-10) as well as dechlorane plus, polybrominated biphenyls, hexabromobenzene, pentabromotoluene and pentabromoethylbenzene (collectively referred to as ∑ FR-7). Plastic, WEEE and vehicles contained the largest amount of flame retardants (∑ BDE-10: 45,000–210,000 μg/kg; ∑ FR-7: 300–13,000 μg/kg). It was hypothesized leachate and air concentrations from facilities that sort/defragment WEEE and vehicles would be the highest. This was supported for total air phase concentrations (∑ BDE-10: 9000–195,000 pg/m3 WEEE/vehicle facilities, 80–900 pg/m3 in incineration/sorting and landfill sites), but not for water leachate concentrations (e.g., ∑ BDE-10: 15–3500 ng/L in WEEE/Vehicle facilities and 1–250 ng/L in landfill sites). Landfill leachate exhibited similar concentrations as WEEE/vehicle sorting and defragmenting facility leachate. To better account for concentrations in leachates at the different facilities, waste-water partitioning coefficients, Kwaste were measured (for the first time to our knowledge for flame retardants). WEEE and plastic waste had elevated Kwaste compared to other wastes, likely because flame retardants are directly added to these materials. The results of this study have implications for the development of strategies to reduce exposure and environmental emissions of flame retardants in waste and recycled products through improved waste management practices.
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