Browsing by Author "Dutta, Kasturi"

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Ambient temperature SNAD process treating anaerobic digester liquor of swine wastewater
(2013-08-01)
Daverey, Achlesh
;
Hung, Nien-Tzu
;
Dutta, Kasturi
;
Lin, Jih-Gaw
;
環境工程研究所
In present study, effluent from anaerobic digestion of swine wastewater was treated by the simultaneous partial nitrification, anaerobic ammonium oxidation and denitrification (SNAD) process using a lab scale 5 L sequencing batch reactor (SBR) under ambient temperature. The fluctuation of anaerobic digester liquor quality (COD, 387 +/- 145 mg/L; TKN, 662 +/- 190 mg/L; NH4+-N, 519 +/- 134 mg/L) and temperature created difficulties to develop a stable SNAD process in the SBR (days 1-285). Fed batch feeding strategy was adopted to have a stable condition in the reactor and overcome the negative effects of organic nitrogen. The average total nitrogen, NH4+-N and COD removal efficiencies in the SBR under steady state conditions (days 485-523) were 80%, 96% and 76%, respectively. The results showed that presence of organic nitrogen, mode of feeding and reactor temperature affects the SNAD process. (C) 2013 Elsevier Ltd. All rights reserved.
Effect of carriers on the performance of anaerobic sequencing batch biofilm reactor treating synthetic municipal wastewater
(2014-11-01)
Dutta, Kasturi
;
Tsai, Cheng-Yu
;
Chen, Wen-Hsing
;
Lin, Jih-Gaw
;
環境工程研究所
In this study, effects of granular activated carbon (GAC) and natural zeolite as attached carriers for microbes on anaerobic treatment of synthetic municipal wastewater were evaluated in laboratory scale anaerobic sequencing batch biofilm reactors (ASBBRs). An anaerobic sequencing batch reactor (ASBR) and three ASBBRs, individually named ASBR-1 without any carrier (control), ASBBR-2 with GAC, ASBBR-3 with zeolite, ASBBR-4 with both GAC and zeolite, were operated at 2.5 d HRT with non-fat dry milk to mimic municipal wastewater. The four reactors were successfully started up and attained steady state within two weeks of operation. Total COD and soluble COD removal efficiencies of more than 93% and 98%, respectively, were observed in the four reactors during steady-state. The average biogas productions for ASBR-1, ASBBR-2, ASBBR-3 and ASBBR-4 were 229, 246, 238 and 278 mI/d, respectively. Addition of carriers improved both the COD removal efficiency and biogas production. Apparently GAC improved COD removal efficiency and zeolite improved gas production. SEM results suggested higher number of biomass attached to GAC than zeolite. (C) 2014 Elsevier Ltd. All rights reserved.
Evolution retrospective for alternative fuels: First to fourth generation
(2014-09-01)
Dutta, Kasturi
;
Daverey, Achlesh
;
Lin, Jih-Gaw
;
環境工程研究所
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Institute of Environmental Engineering
The ever increasing worldwide demand for liquid and gaseous fuels along with overwhelming environmental concerns for greenhouse gas emissions have driven scientists and technologists to consider different alternative energy sources. In past decades, several biomass sources have been identified with increasing potential to be used as new alternative sources of energy - the "Biofuels". The evolution of biofuels is classified into four different generations. In this article an overview of the systematic evolution of different biofuel generations with their advantages and disadvantages has been presented. The advancements in technology, reduction in greenhouse gas emission and assessment of commercial production cost of each generation of biofuel have also been highlighted. Finally this review provides an outlook for a better future generation biofuel. (C) 2014 Elsevier Ltd. All rights reserved.
Removal of pharmaceuticals and organic matter from municipal wastewater using two-stage anaerobic fluidized membrane bioreactor
(2014-08-01)
Dutta, Kasturi
;
Lee, Ming-Yi
;
Lai, Webber Wei-Po
;
Lee, Chien Hsien
;
Lin, Angela Yu-Chen
The aim of present study was to treat municipal wastewater in two-stage anaerobic fluidized membrane bioreactor (AFMBR) (anaerobic fluidized bed reactor (AFBR) followed by AFMBR) using granular activated carbon (GAC) as carrier medium in both stages. Approximately 95% COD removal efficiency could be obtained when the two-stage AFMBR was operated at total HRT of 5 h (2 h for AFBR and 3 h for AFMBR) and influent COD concentration of 250 mg/L. About 67% COD and 99% TSS removal efficiency could be achieved by the system treating the effluent from primary clarifier of municipal wastewater treatment plant, at HRT of 1.28 h and OLR of 5.65 kg COD/m(3) d. The system could also effectively remove twenty detected pharmaceuticals in raw wastewaters with removal efficiency in the range of 86-100% except for diclofenac (78%). No other membrane fouling control was required except scouring effect of GAC for flux of 16 LMH. (C) 2014 Elsevier Ltd. All rights reserved.
Removal of pharmaceuticals and organic matter from municipal wastewater using two-stage anaerobic fluidized membrane bioreactor
(2014-08-01)
Dutta, Kasturi
;
Lee, Ming-Yi
;
Lai, Webber Wei-Po
;
Lee, Chien Hsien
;
Lin, Angela Yu-Chen
The aim of present study was to treat municipal wastewater in two-stage anaerobic fluidized membrane bioreactor (AFMBR) (anaerobic fluidized bed reactor (AFBR) followed by AFMBR) using granular activated carbon (GAC) as carrier medium in both stages. Approximately 95% COD removal efficiency could be obtained when the two-stage AFMBR was operated at total HRT of 5 h (2 h for AFBR and 3 h for AFMBR) and influent COD concentration of 250 mg/L. About 67% COD and 99% TSS removal efficiency could be achieved by the system treating the effluent from primary clarifier of municipal wastewater treatment plant, at HRT of 1.28 h and OLR of 5.65 kg COD/m(3) d. The system could also effectively remove twenty detected pharmaceuticals in raw wastewaters with removal efficiency in the range of 86-100% except for diclofenac (78%). No other membrane fouling control was required except scouring effect of GAC for flux of 16 LMH. (C) 2014 Elsevier Ltd. All rights reserved.
Start-up of simultaneous partial nitrification, anammox and denitrification (SNAD) process in sequencing batch biofilm reactor using novel biomass carriers
(2015-08-01)
Daverey, Achlesh
;
Chen, Yi-Chian
;
Dutta, Kasturi
;
Huang, Yu-Tzu
;
Lin, Jih-Gaw
Simultaneous partial nitrification, anammox and denitrification (SNAD) process was started-up in a 2.5 L sequencing batch biofilm reactor (SBBR) using novel biomass carriers. The SNAD process took only 51 d for start-up at nitrogen loading rate (NLR) and organic loading rate (OLR) of 120 and 60 g/m(3)-d, respectively. Long-term stable operation of SNAD process was observed at NLR and OLR of 360 and 180 g/m(3)-d with average total nitrogen and COD removal efficiencies of >88% and >90%, respectively. The values of conversion ratio Y(NO2-+NO3-)/NH4+ remained below 0.11 after the start-up period, which further confirmed the long-term stability of SNAD process. Results of polymerase chain reaction (PCR), qualitative PCR, and scanning electron microscopic (SEM) analysis of sludge samples confirmed the co-existence and enrichment of AOB, anammox bacteria and denitrifying bacteria in the reactor and biofilm formation on to the carriers. (C) 2015 Elsevier Ltd. All rights reserved.
Statistical analysis to evaluate the effects of temperature and pH on anammox activity
(2015-08-01)
Daverey, Achlesh
;
Chei, Pang Chang
;
Dutta, Kasturi
;
Lin, Jih-Gaw
;
環境工程研究所
Anaerobic ammonium oxidation (anammox) is the most efficient process of nitrogen removal from wastewater. A central composite design was employed to study the individual and interactive effects of temperature and pH on the activity of anammox bacteria. A total of 13 experiments including 5 center point replicates with specific anammox activity as a response were carried out. The maximum specific anammox activity (0.0286 +/- 0.0003 g N-2-N g VSS-1 d(-1)) was observed at temperature and pH of 43 degrees C and 7.5, respectively. The results of estimated regression coefficients for specific anammox activity suggested that both temperature and pH positively affects the specific anammox activity of bacteria. The effect of pH was found to be more significant than temperature as evident from the P value (P < 0.05). Further, contour plot revealed that the interaction between pH and temperature is also significant. Regression model equation was developed to predict the specific anammox activity at particular pH and temperature. The regression model was validated by carrying out experiment at lower temperatures (25, 20 and 15 degrees C) with varying pH, which revealed that an appropriate anammox activity could be maintained at lower temperature by changing pH. The study suggested that higher pH should be maintained in wastewater treatment plant to achieve the high anammox activity at lower temperatures. (C) 2015 Elsevier Ltd. All rights reserved.