The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
Jun Zhu - One of the best experts on this subject based on the ideXlab platform.
-
characteristics of solids bod5 and vfas in liquid swine manure treated by short term low intensity aeration for long term storage
Bioresource Technology, 2006Co-Authors: Zhijian Zhang, Jun ZhuAbstract:A laboratory-scale experiment presents data that reveal the temporal characteristics of solids, biochemical oxygen demand (BOD5) and volatile fatty acids (VFAs) in the aerated liquid swine manure for minimizing Odor generation potential during 190day storage. The performance of 15-day aeration of liquid manure with initial total solids (TS) content from 0.5% to 4.0% was examined at low-intensity aeration rates, i.e., +35 mV oxidation–reduction potential (ORP), 1.0 mg O2/l and 3.0 mg O2/l dissolved oxygen (DO). Odor generation potential was evaluated using VFAs. The aeration process contributed remarkably to the decomposition of TS, total volatile solids (TVS), BOD5 and VFAs. Moreover, the stabilization of manure due to aeration could last up to 190 days. The TS reduction on day 190 ranging from 6.3% to 32.7%, 20.2% to 39.1%, 19.0% to 41.0% were realized under the intensities of +35 mV ORP, 1.0 and 3.0 mg O2/l, respectively. At the same time, the reduction of BOD5 and VFAs reached around 7.8% to 69.5%, 17.2% to 79.9% and 21.9% to 91.1%; 0.4% to 91.0%, 60.4% to 95.0% and 70.4% to 94.1%. The liquid manure with low solids (e.g., TS of 0.5% and 1.0%) offered an advantageous condition for aeration treatment, particularly for biodegradation of BOD5 and VFAs. The Odor generation potential could also be evaluated by the levels of solids and BOD5 in the manure. Increasing aeration intensity would significantly diminish the Odor generation potential for given levels of solids and/or BOD5. Fifteen-day aeration with intensity of 1.0 mg O2/l may be recommended at farm level for both Odor Control and energy savings. 2005 Elsevier Ltd. All rights reserved.
-
a review of microbiology in swine manure Odor Control
Agriculture Ecosystems & Environment, 2000Co-Authors: Jun ZhuAbstract:Generation of Odors is a complex process that involves many bacterial species, producing an extensive array of volatile organic compounds under different manure storage systems currently used. A lack of understanding of the basic microbiology in manure leads to a poor Odor prevention and Control from animal wastes. This review covers pertinent available information about the indigenous bacterial genera in swine manure and their potentials of producing Odorous volatile compounds. It addresses not only the Odorous compounds in swine manure but also the inherent relations between the bacterial species and the related compounds. It also discusses several Odor Control techniques that have been developed based on microbial activities and the limitations with these techniques. Two bacterial genera, Eubacterium and Clostridium, are most likely the major contributors to Odorous volatile fatty acids. It appears that anaerobic lagoons may not be an appropriate choice for treating swine manure for Odor Control due to the reduced methonogenic activities resulted from the low temperatures in lagoon liquid. Also, it seems questionable that the microbial-based manure additives will work, without aeration, in a real storage system for the purpose of Odor Control.
Chungjung Tsai - One of the best experts on this subject based on the ideXlab platform.
-
Single SnO2 gas sensor as a practical tool for evaluating the efficiency of Odor Control engineering at food waste composting plants
Sensors and Actuators B: Chemical, 2012Co-Authors: Chungjung Tsai, Meilien Chen, I-fang MaoAbstract:Abstract The objective of this study was to evaluate the feasibility of using a single tin oxide (SnO 2 ) gas sensor as a simple and reliable tool for evaluating the efficiency of Odor Control engineering at food waste composting plants, by correlating sensor responses with chemical concentrations of critical Odorants and olfactometric data obtained under laboratory and field conditions. Three critical Odorants, including dimethylsulfide, trimethylamine and acetic acid, were prepared in various concentrations, ranging from parts per billion, to parts per million levels. Field samples were collected from two large food waste composting plants in Taiwan. The results indicated that the sensor responses showed significant linear correlation with the chemical concentration of the three target Odorants ( P P 2 gas sensor responses showed a good linear correlation with the olfactometric data for samples inside the composting plants, at exhaust outlets and at downwind boundaries ( P
-
the relationship of Odor concentration and the critical components emitted from food waste composting plants
Atmospheric Environment, 2008Co-Authors: Chungjung Tsai, Meilien Chen, Andi Ye, Mingshean Chou, Shuhung ShenAbstract:Abstract The current official policy regarding food waste management tends towards recycling for composting usage; however, malOdors emitted from food waste composting plants raises other important environmental issues. The objectives of this study are to investigate the critical Odorants of the emission from food waste composting plants and their human olfactory effect in general concentration ranges presented by olfactometric results. The determination of the critical Odorants was made by the analysis of multiple compounds in Odor samples collected inside and outside the plants using gas chromatography–mass spectrometry (GC–MS) and gas detector tubes. The results indicated that six critical Odorants were found in the fields including ethylbenzene, dimethylsulfide, trimethylamine, p -cymene, ammonia and acetic acid. Even ethylbenzene, dimethylsulfide, trimethylamine and p -cymene required similar and extremely low olfactory threshold (0.002 ppm), their olfactometric effect patterns were significantly different; the linear correlation could be found for these compounds in high concentration ranging from 0.25 to 100 ppm ( P P P p -cymene was without any correlation ( P > 0.05). At the same concentration of 5 ppm, the olfactometric results for trimethylamine, dimethylsulfide, p -cymene and ethylbenzene were 21 000, 1000, 300 and 74 Odor Concentration (OC), respectively (the ratio was 284:14:4:1). Trimethylamine contributed the most to this Odor problem. Acetic acid showed a significant linear correlation in concentrations 0.1–50 ppm ( P P > 0.05). This study not only indicated the specific olfactory effect patterns for the critical Odorants emitted from food waste composting plants, but provided the practical information for the Odor Control engineering to judge the elimination priority.
Duujong Lee - One of the best experts on this subject based on the ideXlab platform.
-
anaerobic storage as a pretreatment for enhanced biodegradability of dewatered sewage sludge
Bioresource Technology, 2011Co-Authors: Guanzhao Wang, Liming Shao, Duujong LeeAbstract:Dewatered sewage sludge is often stored still before further processing and final disposal. This study showed that anaerobic storage of dewatered sewage sludge could hydrolyze organic matter from the sludge matrix, and increase soluble organic acid content from 90 to 2400 mg/L and soluble organic carbon content from 220 to 1650 mg/L. Correspondingly, the contents of proteins, celluloses and hemicelluloses were reduced by 2-9%. Applying anaerobic storage markedly enhanced the efficiency of the subsequent bio-drying process on stored sludge. Correspondingly, biogas and Odor gas were produced immediately after commencing the sludge storage. Anaerobic storage with Odor Control can be applied as a pretreatment process for dewatered sewage sludge in wastewater treatment plants.
Yunxiao Chong - One of the best experts on this subject based on the ideXlab platform.
-
index for nitrate dosage calculation on sediment Odor Control using nitrate dependent ferrous and sulfide oxidation interactions
Journal of Environmental Management, 2018Co-Authors: Rong Huang, Yuhai Liang, Yunxiao Chong, Lin WangAbstract:Abstract Nitrate-driven sulfide and ferrous oxidation have received great concern in researches on sediments Odor Control with calcium nitrate addition. However, interrelations among sulfide oxidation, ferrous oxidation and their associated microbes during the nitrate reduction process are rarely reported. In this work, a nNO3/n(S+Fe) ratio (mole ratio of NO3− concentration to S2− and Fe2+ concentration) was first introduced as an index for calcium nitrate dosage calculation. Then certain amount of calcium nitrate was added to four sediment systems with various sulfide and ferrous initial concentration to create four gradients of nNO3/n(S+Fe) ratio (0.6, 0.9, 1.5 and 2.0) for treatment. Furthermore, the significant variations of sulfide and ferrous oxidation, microbial diversity and community structure were observed. The results revealed that at low nNO3/n(S+Fe) ratio (0.6 and 0.9) systems, sulfide seemed prior to ferrous to be oxidized and no obvious ferrous oxidation occurred. Meanwhile, sulfide oxidizing associated genus Sulfurimonas sp. became dominant in these systems. In contrast, sulfide and ferrous oxidation rate increased when nNO3/n(S+Fe) ratio reached 1.5 and 2.0 (two and three times of theoretically required amount for sulfide and ferrous oxidation), which made Thiobacillus sp. more dominant than Sulfurimonas sp. Hence, when nNO3/n(S+Fe) ratio of 1.5 and 2.0 were used, sulfide and ferrous could be simultaneously oxidized and no sulfide regeneration appeared in two months. These results demonstrated that for sulfide- and ferrous-rich sediment treatment, the nitrate consumed by ferrous oxidation should be taken into account when calculating the nitrate injecting dosage. Moreover, nNO3/n(S+Fe) ratio was feasible as a key parameter to Control the oxidation process and as an index for calcium nitrate dosage calculation.
-
temperature response of sulfide ferrous oxidation and microbial community in anoxic sediments treated with calcium nitrate addition
Journal of Environmental Management, 2017Co-Authors: Xinxian Long, Yunxiao Chong, Wen Xing, Ziao ZhuAbstract:Abstract Nitrate-driven sulfide oxidation has been proved a cost-effective way to Control sediments Odor which has long been a universal problem for urban rivers in south China areas. In this work, sediments treatment experiments under a dynamic variation of temperature from 5 °C to 35 °C with 3% of calcium nitrate added were conducted to reveal the influence of temperature variation on this process. The results showed that microbial community was remarkably restructured by temperature variation. Pseudomonas (15.56–29.31%), Sulfurimonas (26.81%) and Thiobacillus (37.99%) were dominant genus at temperature of ≤15 °C, 25 °C and 35 °C, respectively. It seemed that species enrichment occurring at different temperature gradient resulted in the distinct variation of microbial community structure and diversity. Moreover, nitrate-driven sulfide and ferrous oxidation were proportionally promoted only when temperature increased above 15 °C. The dominant bacteria at high temperature stage were those genus that closely related to autotrophic nitrate-driven sulfide and ferrous oxidizing bacteria (e.g.Thiobacillus, Sulfurimonas and Thermomonas), revealing that promotion of sulfide/ferrous oxidation could be attributed to the change of dominant bacteria determined by temperature variation. Thus, a higher treatment efficiency by calcium nitrate addition for Odor Control would be achieved in summer than any other seasons in south China areas.
-
potential risk assessment of heavy metals in sediments during the denitrification process enhanced by calcium nitrate addition effect of avs residual
Ecological Engineering, 2016Co-Authors: Lin Wang, Xinxian Long, Yunxiao ChongAbstract:Abstract Calcium nitrate addition has been proved to be a effective technology for sediment Odor Control, however, when sulfide was oxidized, metals those combined to sulfide might potentially threatened the aquatic ecosystem. In this work, for the purpose of assessing the effect of acid volatile sulfide (AVS) residual on ecological risk of heavy metals (Cu, Cd, Pb and Zn) in anoxic sediments during the denitrification, limited calcium nitrate (20 g/kg dw) was added into sediments in microcosm systems, and then was exhausted within two weeks, along with 95.0% AVS removed. During the treatment, simultaneously extracted metal (SEM) to AVS ratio increased with sulfide removal, but remained lower than 1 because of the residual of AVS. Furthermore, geoaccumulation index (Igeo), sediment quality guidelines (SQGs) and risk assessment code (RAC) all indicated that the risk level of all metals in treated sediments showed no significant change compared to that in initial sediments. It suggested that certain content of AVS residual could keep ecological risk of heavy metals at a low level during the treatment with calcium nitrate addition. However, limitations of each assessment index were observed as well. Igeo and SQGs were found to be unsuitable for temporal dynamic evaluation, but useful for identifying which metal got higher pollution level and risk level, and thus deserved more concerns. In addition, RAC was appropriate for Cu assessment rather than Zn, Cd and Pb evaluation, while AVS–SEM method was suitable for Zn, Cd and Pb evaluation instead of Cu assessment. Thus, all these indexes should be taken into account as a whole when used.
Meilien Chen - One of the best experts on this subject based on the ideXlab platform.
-
Single SnO2 gas sensor as a practical tool for evaluating the efficiency of Odor Control engineering at food waste composting plants
Sensors and Actuators B: Chemical, 2012Co-Authors: Chungjung Tsai, Meilien Chen, I-fang MaoAbstract:Abstract The objective of this study was to evaluate the feasibility of using a single tin oxide (SnO 2 ) gas sensor as a simple and reliable tool for evaluating the efficiency of Odor Control engineering at food waste composting plants, by correlating sensor responses with chemical concentrations of critical Odorants and olfactometric data obtained under laboratory and field conditions. Three critical Odorants, including dimethylsulfide, trimethylamine and acetic acid, were prepared in various concentrations, ranging from parts per billion, to parts per million levels. Field samples were collected from two large food waste composting plants in Taiwan. The results indicated that the sensor responses showed significant linear correlation with the chemical concentration of the three target Odorants ( P P 2 gas sensor responses showed a good linear correlation with the olfactometric data for samples inside the composting plants, at exhaust outlets and at downwind boundaries ( P
-
the relationship of Odor concentration and the critical components emitted from food waste composting plants
Atmospheric Environment, 2008Co-Authors: Chungjung Tsai, Meilien Chen, Andi Ye, Mingshean Chou, Shuhung ShenAbstract:Abstract The current official policy regarding food waste management tends towards recycling for composting usage; however, malOdors emitted from food waste composting plants raises other important environmental issues. The objectives of this study are to investigate the critical Odorants of the emission from food waste composting plants and their human olfactory effect in general concentration ranges presented by olfactometric results. The determination of the critical Odorants was made by the analysis of multiple compounds in Odor samples collected inside and outside the plants using gas chromatography–mass spectrometry (GC–MS) and gas detector tubes. The results indicated that six critical Odorants were found in the fields including ethylbenzene, dimethylsulfide, trimethylamine, p -cymene, ammonia and acetic acid. Even ethylbenzene, dimethylsulfide, trimethylamine and p -cymene required similar and extremely low olfactory threshold (0.002 ppm), their olfactometric effect patterns were significantly different; the linear correlation could be found for these compounds in high concentration ranging from 0.25 to 100 ppm ( P P P p -cymene was without any correlation ( P > 0.05). At the same concentration of 5 ppm, the olfactometric results for trimethylamine, dimethylsulfide, p -cymene and ethylbenzene were 21 000, 1000, 300 and 74 Odor Concentration (OC), respectively (the ratio was 284:14:4:1). Trimethylamine contributed the most to this Odor problem. Acetic acid showed a significant linear correlation in concentrations 0.1–50 ppm ( P P > 0.05). This study not only indicated the specific olfactory effect patterns for the critical Odorants emitted from food waste composting plants, but provided the practical information for the Odor Control engineering to judge the elimination priority.
