The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
Jun Zhu - One of the best experts on this subject based on the ideXlab platform.
-
Application of A Surface Aeration System with Venturi Injectors to Reduce Odor Generation Potential: A Field-scale Study
2009 Reno Nevada June 21 - June 24 2009, 2009Co-Authors: C. Dong, Jun Zhu, Curtis F MillerAbstract:A field-scale surface aeration system was tested from mid-June to mid-October in this study. About 0.14 ha (1/3 acre) of the liquid manure storage was surface-aerated continuously for four months, with the unaerated portion as the control. The aeration system consisted of a venturi air injector module, a 1.1 kW centrifugal pump, and a distribution frame made of PVC pipes. The results indicated that the solids removal efficiencies were 39.64% for TVS and 16.55% for TS after four months of aeration, while the ratio of TVS to TS decreased from about 49% to 31%. In the first seven weeks, the BOD removal efficiency was lower than 20% (9% on average) but increased linearly from 21.5% to 86.5% during the rest operating time. The VFAs removal efficiency increased from 5% at the beginning to 85% at the end of the experiment, with the VFAs level in the aerated liquid manure was reduced to below 230 mg/L. The linear coefficient between BOD and VFAs was 0.87. The results show that a DO level lower than 0.5 mg/L can still be effective in controlling Odor. The electricity cost for running the surface aeration system was estimated at $0.21 per pig finished.
-
A Field-Scale Surface Aeration System to Reduce Odor Generation
Transactions of the ASABE, 2009Co-Authors: C. Dong, Jun Zhu, C. MillerAbstract:A field-scale surface aeration system was tested from mid-June to mid-October in this study. About 0.14 ha (1/3 acre) of the liquid manure storage was surface-aerated continuously for four months, with the unaerated portion as the control. The aeration system consisted of a venturi air injector module, a 1.1 kW centrifugal pump, and a distribution frame made of PVC pipes. The results indicated that the solids removal efficiencies were 39.64% for TVS and 16.55% for TS after four months of aeration, while the ratio of TVS to TS decreased from about 49% to 31%. In the first seven weeks, the BOD removal efficiency was lower than 20% (9% on average) but increased linearly from 21.5% to 86.5% during the rest operating time. The VFA removal efficiency increased from 5% at the beginning to 85% at the end of the experiment, with the VFA level in the aerated liquid manure was reduced to below 230 mg/L. The linear coefficient between BOD and VFAs was 0.87. The results show that a DO level lower than 0.5 mg/L can still be effective in controlling Odor. The electricity cost for running the surface aeration system was estimated at $0.21 per pig finished.
-
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.
-
Effects of bioreactor temperature and time on Odor-related parameters in aerated swine manure slurries.
Environmental technology, 2003Co-Authors: Pius M. Ndegwa, Jun Zhu, A. LuoAbstract:Previous studies have linked Odor Generation from swine manure to some characteristics of the liquid manure such oxidation-reduction potential (ORP), five-day biochemical oxygen demand (BOD5), volatile fatty acids (VFAs), and predominant microbial population. This study investigated the effect of bioreactor temperature and time on the aforementioned parameters during aeration of swine manure. Five reactors (13 1 capacity) loaded with swine manure and maintained at temperatures of 5, 10, 15, 20, and 25 degrees C, were supplied with air for 15 days to maintain aerobic conditions. Large fluctuations in ORP (-120 to 360 mV) were observed in the first seven days of aeration, which stabilized thereafter regardless of the bioreactor temperature. The percentage removal of VFAs and BOD5 in the manure significantly increased from 0.0% on day one to 87.8% and 65.3%, respectively, on day nine, and remained relatively constant thereafter. The mean percentage of VFAs and BOD5 removed also increased significantly with an increase in the bioreactor temperature. The VFAs and BOD5 removal increased by approximately 25% and 35%, respectively, in going from 5 to 25 degrees C, during the 15 days of aeration. Both VFAs and BOD5 in the manure were significantly correlated with ORP, aerobic bacteria, and anaerobic bacteria. The data suggested that continued aeration for seven days at 20 or 25 degrees C was sufficient for significant reduction of Odor precursors (VFAs and BOD5) and in stabilization of swine manure. A linear correlation of 0.97 between VFAs and BOD5 indicated that the two parameters can be used interchangeably as indicators of Odor release potential in swine manure.
-
BACTERIAL RESPONSES TO TEMPERATURE DURING AERATION OF PIG SLURRY
Journal of environmental science and health. Part. B Pesticides food contaminants and agricultural wastes, 2002Co-Authors: Jun Zhu, Pius M. Ndegwa, Ancheng LuoAbstract:The temperature effect on total anaerobic and aerobic bacterial growth in pig slurry was studied using low level batch aeration treatments. Five bioreactors were built using Plexiglas tubes to perform five temperature treatments (5 °C, 10 °C, 15 °C, 20 °C, and 25 °C). An airflow rate of 0.129 L/min/L manure was used to aerate manure contained in all reactors. Data showed that temperature had a profound impact on the aerobic counts in pig slurry during the aeration process. When the temperature increased from 15 °C to 25 °C, the average oxidation–reduction potential decreased from +40 mV to −60 mV, accompanied by a 75% reduction of aerobic bacteria in the manure. At 25 °C, the anaerobic counts were consistently higher than aerobic counts for most of days. A quadratic relationship was observed between the aerobic counts and the oxidation–reduction potential with a correlation coefficient of 0.8374. To reduce Odor Generation potential, the oxidation–reduction potential in the manure should be maintained at +...
Pius M. Ndegwa - One of the best experts on this subject based on the ideXlab platform.
-
Effects of cycle-frequency and temperature on the performance of anaerobic sequencing batch reactors (ASBRs) treating swine waste
Bioresource technology, 2007Co-Authors: Pius M. Ndegwa, Douglas W. Hamilton, Jerald A. Lalman, H. J. CumbaAbstract:Anaerobic digestion of animal waste is a technically viable process for the abatement of adverse environmental impacts caused by animal wastes; however, widespread acceptance has been plagued by poor economics. This situation is dismal if the technology is adapted for treating low strength animal slurries because of large digester-volume requirements and a corresponding high energy input. A possible technology to address these constraints is the anaerobic sequencing batch reactor (ASBR). The ASBR technology has demonstrated remarkable potential to improve the economics of treating dilute animal waste effluents. This paper presents preliminary data on the effects of temperature and frequency-cycle on the operation of an ASBR at a fixed hydraulic retention time (HRT). The results suggest that within the parameter range under consideration, temperature did not affect the biogas yield significantly, however, higher cycle-frequency had a negative effect. The biogas quality (%CH4) was not significantly affected by temperature nor by the cyclefrequency. The operating principle of the ASBR follows four phases: feed, react, settle, and decant in a cyclic mode. To improve the biogas production in an ASBR, one long react-phase was preferable compared to three shorter react-phases. Treatment of dilute manure slurries in an ASBR at 20 C was more effective than at 35 C; similarly more bio-stable effluents were obtained at low cycle-frequency. The treatment of dilute swine slurries in an ASBR at the lower temperature (20 C) and lower cycle-frequency is, therefore, recommended for the bio-stabilization of dilute swine wastewaters. The results also indicate that significantly higher VFA degradation occurred at 20 C than at 35 C, suggesting that the treatment of dilute swine slurries in ASBRs for Odor control might be more favorable at the lower than at the higher temperatures examined in this study. Volatile fatty acid reduction at the two reactor temperatures and cyclefrequencies, from a high of 639 ± 75 mg/L to a low of 92 ± 23 mg/L, greatly reduced the Odor and the Odor-Generation potential in post-treatment storage. The nutrients (both N and P) in the waste influent were conserved in the effluents. Published by Elsevier Ltd.
-
Optimization of anaerobic sequencing batch reactors treating dilute swine slurries
Transactions of the ASAE, 2005Co-Authors: Pius M. Ndegwa, Douglas W. Hamilton, Jerald A. Lalman, H. J. CumbaAbstract:Use of anaerobic digestion for the treatment and recovery of biogas from concentrated animal waste effluents is a technically viable approach, but widespread acceptance has been limited due to poor economics. This challenge is magnified several-fold when considering anaerobic digestion of low-strength or dilute animal slurries because of the larger digester volumes and the corresponding high energy input requirements. These constraints could be mitigated by using an anaerobic sequencing batch reactor (ASBR). This technology has shown tremendous potential to improve the economics for the treatment of dilute animal waste effluents. This article reports preliminary optimization (biogas production and organic strength reduction) of an ASBR treating dilute swine slurries from pit-recharge manure management systems commonly found in confined swine housing. Based on the results, optimum biogas yields from anaerobic digestion of low-strength swine waste (0.3% to 0.4% TS) were approximately 0.14 mL/mg COD and 0.16 mL/mg COD at 5.25 and 6 days HRT at digestion temperatures of 20°C and 35°C, respectively. Higher operational temperature improved the specific biogas yield, but the qualities of biogas produced at the two temperatures, although high (65% to 70% CH4 and 17% to 20% CO2), were not significantly different. Maximum COD reductions of approximately 90% and 84% would be achieved at 7.2 and 9.1 days HRT at digestion temperatures of 20°C and 35°C, respectively. Higher COD reduction (implying more bio-stabilization of slurry) in the lower-temperature digester was attributed to less biomass washout, which is likely due to more efficient solids settling. The volatile fatty acids at both reactor temperatures were reduced from a mean of 639 ±75 mg/L in the influent to mean values of 74 ±12 and 85 ±17 mg/L in the effluents at 20°C and 35°C, respectively, which significantly mitigated the potential of Odor Generation from the effluents. Additionally, it was observed that the nutrient (both N and P) levels in the effluents remained about the same as in the influent.
-
Treatment of Low Strength Swine Waste Using Anaerobic Sequencing Batch Reactors (ASBRs)
2005 Tampa FL July 17-20 2005, 2005Co-Authors: Pius M. Ndegwa, Douglas W. Hamilton, Jerald A. Lalman, H. J. CumbaAbstract:Use of anaerobic digestion for the treatment and recovery of biogas from animal waste has a long history but its adoption has been hindered by to poor economics. The economic challenges are even worse when considering anaerobic digestion of low strength animal wastewaters because of large volumes of reactors and the corresponding high energy input requirements. A relatively new reactor-technology known as anaerobic sequencing batch reactor (ASBR), has shown promise of improving the economics of the treatment of such dilute wastewaters. This paper reports preliminary optimization studies of an ASBR treating dilute swine slurries from pitrecharge manure management systems. Based on the results, optimum biogas yields from anaerobic digestion of low strength swine waste (0.3 - 0.4% TS) were approximately 0.14 mL/mg COD and 0.16 mL/mg COD at a HRT of 5.25, and 6 days at digestion temperatures of 20oC and 35oC, respectively. Higher operational temperatures improved the specific biogas yield but the qualities of biogas produced at the two temperatures (65 – 70% CH4 and 17 – 20% CO2) were not significantly different. On the other hand, higher cycle-frequency for the same HRT significantly decreased the biogas yield but not the quality of the biogas produced. Maximum COD reductions of approximately 90 and 84% were achieved at HRTs of 7.2 and 9.1 days, at digestion temperatures of 20oC and 35oC, respectively. Higher COD reduction (implying more bio-stabilized effluents) in the lower-temperature digester was attributed to less biomass wash-out most probably due to more efficient solids settling. Results of suspended solids in the effluents showed that effectiveness of settling was degraded by higher cycle-frequency. The volatile fatty acids reduction at both reactortemperatures and the two cycle-frequencies (1 and 3 cycles/day) were significantly high from a mean of 639 mg/L in the influent to means less than 120 mg/L in the effluents; significantly mitigating the potential of Odor Generation from the effluents. Additionally, it was observed that the nutrients (both N and P) levels in the effluents remained about the same as in the influents during the entire testperiod.
-
Effects of bioreactor temperature and time on Odor-related parameters in aerated swine manure slurries.
Environmental technology, 2003Co-Authors: Pius M. Ndegwa, Jun Zhu, A. LuoAbstract:Previous studies have linked Odor Generation from swine manure to some characteristics of the liquid manure such oxidation-reduction potential (ORP), five-day biochemical oxygen demand (BOD5), volatile fatty acids (VFAs), and predominant microbial population. This study investigated the effect of bioreactor temperature and time on the aforementioned parameters during aeration of swine manure. Five reactors (13 1 capacity) loaded with swine manure and maintained at temperatures of 5, 10, 15, 20, and 25 degrees C, were supplied with air for 15 days to maintain aerobic conditions. Large fluctuations in ORP (-120 to 360 mV) were observed in the first seven days of aeration, which stabilized thereafter regardless of the bioreactor temperature. The percentage removal of VFAs and BOD5 in the manure significantly increased from 0.0% on day one to 87.8% and 65.3%, respectively, on day nine, and remained relatively constant thereafter. The mean percentage of VFAs and BOD5 removed also increased significantly with an increase in the bioreactor temperature. The VFAs and BOD5 removal increased by approximately 25% and 35%, respectively, in going from 5 to 25 degrees C, during the 15 days of aeration. Both VFAs and BOD5 in the manure were significantly correlated with ORP, aerobic bacteria, and anaerobic bacteria. The data suggested that continued aeration for seven days at 20 or 25 degrees C was sufficient for significant reduction of Odor precursors (VFAs and BOD5) and in stabilization of swine manure. A linear correlation of 0.97 between VFAs and BOD5 indicated that the two parameters can be used interchangeably as indicators of Odor release potential in swine manure.
-
BACTERIAL RESPONSES TO TEMPERATURE DURING AERATION OF PIG SLURRY
Journal of environmental science and health. Part. B Pesticides food contaminants and agricultural wastes, 2002Co-Authors: Jun Zhu, Pius M. Ndegwa, Ancheng LuoAbstract:The temperature effect on total anaerobic and aerobic bacterial growth in pig slurry was studied using low level batch aeration treatments. Five bioreactors were built using Plexiglas tubes to perform five temperature treatments (5 °C, 10 °C, 15 °C, 20 °C, and 25 °C). An airflow rate of 0.129 L/min/L manure was used to aerate manure contained in all reactors. Data showed that temperature had a profound impact on the aerobic counts in pig slurry during the aeration process. When the temperature increased from 15 °C to 25 °C, the average oxidation–reduction potential decreased from +40 mV to −60 mV, accompanied by a 75% reduction of aerobic bacteria in the manure. At 25 °C, the anaerobic counts were consistently higher than aerobic counts for most of days. A quadratic relationship was observed between the aerobic counts and the oxidation–reduction potential with a correlation coefficient of 0.8374. To reduce Odor Generation potential, the oxidation–reduction potential in the manure should be maintained at +...
H. J. Cumba - One of the best experts on this subject based on the ideXlab platform.
-
Effects of cycle-frequency and temperature on the performance of anaerobic sequencing batch reactors (ASBRs) treating swine waste
Bioresource technology, 2007Co-Authors: Pius M. Ndegwa, Douglas W. Hamilton, Jerald A. Lalman, H. J. CumbaAbstract:Anaerobic digestion of animal waste is a technically viable process for the abatement of adverse environmental impacts caused by animal wastes; however, widespread acceptance has been plagued by poor economics. This situation is dismal if the technology is adapted for treating low strength animal slurries because of large digester-volume requirements and a corresponding high energy input. A possible technology to address these constraints is the anaerobic sequencing batch reactor (ASBR). The ASBR technology has demonstrated remarkable potential to improve the economics of treating dilute animal waste effluents. This paper presents preliminary data on the effects of temperature and frequency-cycle on the operation of an ASBR at a fixed hydraulic retention time (HRT). The results suggest that within the parameter range under consideration, temperature did not affect the biogas yield significantly, however, higher cycle-frequency had a negative effect. The biogas quality (%CH4) was not significantly affected by temperature nor by the cyclefrequency. The operating principle of the ASBR follows four phases: feed, react, settle, and decant in a cyclic mode. To improve the biogas production in an ASBR, one long react-phase was preferable compared to three shorter react-phases. Treatment of dilute manure slurries in an ASBR at 20 C was more effective than at 35 C; similarly more bio-stable effluents were obtained at low cycle-frequency. The treatment of dilute swine slurries in an ASBR at the lower temperature (20 C) and lower cycle-frequency is, therefore, recommended for the bio-stabilization of dilute swine wastewaters. The results also indicate that significantly higher VFA degradation occurred at 20 C than at 35 C, suggesting that the treatment of dilute swine slurries in ASBRs for Odor control might be more favorable at the lower than at the higher temperatures examined in this study. Volatile fatty acid reduction at the two reactor temperatures and cyclefrequencies, from a high of 639 ± 75 mg/L to a low of 92 ± 23 mg/L, greatly reduced the Odor and the Odor-Generation potential in post-treatment storage. The nutrients (both N and P) in the waste influent were conserved in the effluents. Published by Elsevier Ltd.
-
Optimization of anaerobic sequencing batch reactors treating dilute swine slurries
Transactions of the ASAE, 2005Co-Authors: Pius M. Ndegwa, Douglas W. Hamilton, Jerald A. Lalman, H. J. CumbaAbstract:Use of anaerobic digestion for the treatment and recovery of biogas from concentrated animal waste effluents is a technically viable approach, but widespread acceptance has been limited due to poor economics. This challenge is magnified several-fold when considering anaerobic digestion of low-strength or dilute animal slurries because of the larger digester volumes and the corresponding high energy input requirements. These constraints could be mitigated by using an anaerobic sequencing batch reactor (ASBR). This technology has shown tremendous potential to improve the economics for the treatment of dilute animal waste effluents. This article reports preliminary optimization (biogas production and organic strength reduction) of an ASBR treating dilute swine slurries from pit-recharge manure management systems commonly found in confined swine housing. Based on the results, optimum biogas yields from anaerobic digestion of low-strength swine waste (0.3% to 0.4% TS) were approximately 0.14 mL/mg COD and 0.16 mL/mg COD at 5.25 and 6 days HRT at digestion temperatures of 20°C and 35°C, respectively. Higher operational temperature improved the specific biogas yield, but the qualities of biogas produced at the two temperatures, although high (65% to 70% CH4 and 17% to 20% CO2), were not significantly different. Maximum COD reductions of approximately 90% and 84% would be achieved at 7.2 and 9.1 days HRT at digestion temperatures of 20°C and 35°C, respectively. Higher COD reduction (implying more bio-stabilization of slurry) in the lower-temperature digester was attributed to less biomass washout, which is likely due to more efficient solids settling. The volatile fatty acids at both reactor temperatures were reduced from a mean of 639 ±75 mg/L in the influent to mean values of 74 ±12 and 85 ±17 mg/L in the effluents at 20°C and 35°C, respectively, which significantly mitigated the potential of Odor Generation from the effluents. Additionally, it was observed that the nutrient (both N and P) levels in the effluents remained about the same as in the influent.
-
Treatment of Low Strength Swine Waste Using Anaerobic Sequencing Batch Reactors (ASBRs)
2005 Tampa FL July 17-20 2005, 2005Co-Authors: Pius M. Ndegwa, Douglas W. Hamilton, Jerald A. Lalman, H. J. CumbaAbstract:Use of anaerobic digestion for the treatment and recovery of biogas from animal waste has a long history but its adoption has been hindered by to poor economics. The economic challenges are even worse when considering anaerobic digestion of low strength animal wastewaters because of large volumes of reactors and the corresponding high energy input requirements. A relatively new reactor-technology known as anaerobic sequencing batch reactor (ASBR), has shown promise of improving the economics of the treatment of such dilute wastewaters. This paper reports preliminary optimization studies of an ASBR treating dilute swine slurries from pitrecharge manure management systems. Based on the results, optimum biogas yields from anaerobic digestion of low strength swine waste (0.3 - 0.4% TS) were approximately 0.14 mL/mg COD and 0.16 mL/mg COD at a HRT of 5.25, and 6 days at digestion temperatures of 20oC and 35oC, respectively. Higher operational temperatures improved the specific biogas yield but the qualities of biogas produced at the two temperatures (65 – 70% CH4 and 17 – 20% CO2) were not significantly different. On the other hand, higher cycle-frequency for the same HRT significantly decreased the biogas yield but not the quality of the biogas produced. Maximum COD reductions of approximately 90 and 84% were achieved at HRTs of 7.2 and 9.1 days, at digestion temperatures of 20oC and 35oC, respectively. Higher COD reduction (implying more bio-stabilized effluents) in the lower-temperature digester was attributed to less biomass wash-out most probably due to more efficient solids settling. Results of suspended solids in the effluents showed that effectiveness of settling was degraded by higher cycle-frequency. The volatile fatty acids reduction at both reactortemperatures and the two cycle-frequencies (1 and 3 cycles/day) were significantly high from a mean of 639 mg/L in the influent to means less than 120 mg/L in the effluents; significantly mitigating the potential of Odor Generation from the effluents. Additionally, it was observed that the nutrients (both N and P) levels in the effluents remained about the same as in the influents during the entire testperiod.
María Ángeles Martín - One of the best experts on this subject based on the ideXlab platform.
-
Full-scale composting of sewage sludge and market waste: Stability monitoring and Odor dispersion modeling.
Environmental research, 2018Co-Authors: M. Toledo, M.c. Gutiérrez, José A. Siles, María Ángeles MartínAbstract:Abstract The aim of this study was to assess the Odor immission derived from full-scale composting of different abundant and highly pollutant organic waste: sewage sludge with bulking agent (SL), sewage sludge pretreated through anaerobic digestion and supplemented with bulking agent (SL-AD), and market waste with olive leaves (MW-OL). The combination of dynamic olfactometry and Gaussian dispersion modeling allowed both the quantification of Odor emissions from each waste and the evaluation of their global Odorous impact in nearby urban areas. Wind speed, summer and winter seasons, and atmospheric conditions were considered in the dispersion model. The results revealed that high wind speed (2.6 m/s) increases the global Odor immission in summer season, independently of atmospheric stability. However, the maximum Odor immission concentration recommended for composting process was not exceeded in any case, which depends on each country/region. The experimental results also enable to evaluate the influence of several physico-chemical variables on Odor emissions derived from composting. The removal of nitrogen and volatile solids was the main cause for Odor Generation. Moreover, the microbiological activity of each substrate was monitored throughout the process and different percentages of biodegradability were quantified depending on the type of substrate and pretreatment applied.
-
Centralized management of sewage sludge and agro-industrial waste through co-composting.
Journal of environmental management, 2017Co-Authors: M.c. Gutiérrez, Antonio Serrano, José A. Siles, A.f. Chica, María Ángeles MartínAbstract:In this research study, the co-composting process of a waste mixture containing strawberry extrudate, fish waste, sewage sludge and bulking agent (SEFW, 190:1:22:90 ratio) was carried out in a dynamic-solid respirometer at pilot scale. The aerobic biodegradability of the mixture was previously ensured in a static-liquid respirometer. The advantages and drawbacks of the SEFW co-composting process were subsequently identified through the determination of respirometric activity and the physical-chemical characterization of the waste, as well as the monitoring of Odor emissions. The evolution of the physical-chemical variables showed that pH increased slightly and that the organic matter concentration, expressed as volatile solids (VS, %) or oxidable organic carbon (COXC, %), decreased by around 15% in both cases and by approximately 56% in its biodegradable form (total organic carbon, TOC, %). The low Odor emission rate (OER) in the least favorable scenario (the maximum Odor Generation) during SEFW composting was 1.59 ouE/s, whereas this figure reached 3.52 ouE/s when only the organic fraction of municipal solid waste (OFMSW) was composted. Consequently, the co-composting of SEFW is more favorable in terms of Odor emission and permits the simultaneous treatment of different types of waste.
Mukesh Kumar Awasthi - One of the best experts on this subject based on the ideXlab platform.
-
Response of bamboo biochar amendment on volatile fatty acids accumulation reduction and humification during chicken manure composting.
Bioresource technology, 2019Co-Authors: Yumin Duan, Zengqiang Zhang, Sanjeev Kumar Awasthi, Tao Liu, Mukesh Kumar AwasthiAbstract:Present study was focused on to evaluate the effectiveness of increasing bamboo biochar (BB) (0%, 2%, 4%, 6%, 8% and 10%) amendment on volatile fatty acids (VFAs) degradation and humification, as well as correlation with interrelated physicochemical parameters during chicken manure (CM) composting. The results showed that the extended thermophilic period and higher humic acid/fulvic acid ratio as well as richness bacteria community during CM composting. In addition, lower quantities of VFAs and Odor Generation with elevated biochar concentration. Redundancy analysis also supported that 10% BB has strong correlation with physicochemical parameters than other treatments. Overall, the 10% BB amendment could stimulate microbial activities to accelerate the organic waste degradation, reduced VFAs and Odor emission so that improve hygiene and end product quality. It is notably assessed that application of 10% BB additive were optimal feasible and effectively channel for disposal of manure.
-
Influence of biochar on volatile fatty acids accumulation and microbial community succession during biosolids composting
Bioresource Technology, 2017Co-Authors: Mukesh Kumar Awasthi, Sanjeev Kumar Awasthi, Quan Wang, Zhen Wang, Altaf Hussain Lahori, Hongyu Chen, Meijing Wang, Junchao Zhao, Zengqiang ZhangAbstract:Abstract The impact of biochar amendment on volatile fatty acids (VFAs) and Odor Generation during the biosolids-wheat straw composting was investigated. Five treatments were design using the same mixture of biosolids-wheat straw with different dosage of biochar blending (2%, 4%, 8% and 12% on dry weight basis) and without biochar applied treatment served as control. The results of VFAs and Odour Index (OI) profile designated that compost with 8–12% biochar became more rapidly humified with less quantity of VFAs and OI Generation content compared to control. Consequently, the VFAs degrading and total bacterial abundance are also significantly higher recorded in 8–12% biochar than 2% biochar and control. In addition, 8–12% biochar applied treatment has significantly maximum close correlation among the all physicochemical and gaseous emission parameters. Finally, results designated that higher dosage of biochar (8–12% biochar) was more feasible approach for biosolids composting.
