Two-Stage Anaerobic Treatment of Dairy Wastewater Using HUASB with PUF and PVC Carrier

Banu, J. Rajesh,Kaliappan, S.,Yeom, Ick-Tae Korean Society for Biotechnology and Bioengineerin 2007 Biotechnology and Bioprocess Engineering Vol.12 No.3

In the present study, an attempt has been made to treat dairy wastewater entirely via anaerobic treatment over a period of 215 days, using two-stage Hybrid Upflow Anaerobic Sludge Blanket (HUASB) reactors, which offer the advantages associated both with fixed film and upflow sludge blanket treatments. A HUASB with polyurethane foam cubes was used for stage I, and a HUASB utilizing PVC-cut rings was used for stage II. The output from stage I was used as the input for stage II. The two-stage reactor was operated at an organic loading rate that varied from 10.7 to 21.4kg $COD\;m^3/d$ for a period of 215 days, including the start-up period. The ideal organic loading rate for the two-stage reactor was 19.2kg $COD/m^3/d$. A further 21.4 kg $COD\;m^3/d$ increase in the organic loading rate resulted in the souring of the reactor function in stage I, which consequently reduced the overall reactor performance. Combined COD removal during the stable operation period (10.7 to 19.2kg $COD\;m^3/d$) occurred in a range between 97 and 99%. The methane content in the biogas varied from 65 to 70% in stage I, and from 63 to 66% in stage II. The two-stage anaerobic treatment using HUASB with PUF and PVC described in this work is expected to constitute a better alternative for the complete treatment of dairy wastewater than high-rate anaerobic, anaerobic/aerobic, and two-phase anaerobic treatment methods.

A study on the performance of a pilot scale A2/0-MBR system in treating domestic wastewater.

Banu, J Rajesh,Uan, Do Khac,Chung, Ik-Jae,Kaliappan, S,Yeom, Ick-Tae The Academy 2009 Journal of environmental biology Vol.30 No.6

<P>Phosphorus and nitrogen are the important eutrophication nutrients. They were removed in the anaerobic/anoxic/oxic (A2/O) system through biologically. The use of pilot scale A2/O systems with immersed membranes in removing nutrients phosphorus and nitrogen were investigated over a period of 150 days. The A2/O membrane bio reactor (MBR) was operated at a flux of 17 LMH. The designed flux was increased stepwise over a period of one week. The reactor was operated with the mixed liquid suspended solids (MLSS) concentrations in the range of 7000-8000 mg l(-1). The phosphorus removal was found to be in the range of 74-84%. The ammonification was completed in the aerobic zone and the ammonia concentration was almost nil. Nitrate concentration in the anoxic zone was found to be in the range of 0.3-1.6 mg l(-1) indicating efficient denitrification. The nitrogen removal efficiency of the A2/O-MBR system was in the range of 68 to 75%. The chemical oxygen demand (COD) in the effluent was in the range of 8-5 mgl(-1) indicating the efficiency of membrane. During the period of reactor operation transmembrane pressure (TMP) of the reactor increased slowly from 0 to 6 -cmHg over a period of 150 days.</P>

Biomanagement of sago-sludge using an earthworm, Eudrilus eugeniae.

Banu, J Rajesh,Yeom, Ick Tae,Esakkiraj, S,Kumar, Naresh,Logakanthi, S The Academy 2008 Journal of environmental biology Vol.29 No.2

<P>Sago, the tapioca starch is manufactured by over 800 small-scale units located in the Salem district, Tamil Nadu, India. During the processing of sago it generates huge quantities of biodegradable solid waste, as crushed tubers. In present study an attempt was made to convert these biodegradable solid sago tubers into value added compost using an exotic earthworm, Eudrilus eugeniae. The experiments were carried out in a plastic tray at various concentrations of sago-sludge (50% 75% and 100%) for a period of 90 days. During the vermicomposting, data were collected on life form (cocoon, non clitellates, clitellates) of earthworm and it was found to be high in 50% followed by 75% and 100% concentrations. Chemical analysis of worked substrates showed a step wise increase of nitrogen and phosphorus. The fold increase of phosphorus and nitrogen were found to be high for sago-sludge undergoing vermicomposting than the control. During the composting period the organic carbon decreased from its initial value of 58, 76 and 107 mg/kg to 21, 24 and 65 mg/kg for 50, 70 and 100%, respectively The microbial analysis showed that after 75 days of composting, their population stabilized and further increase in composting period did not increase their population size. The results indicate that 50% and 75% concentration of sludge mixed with bedding material was ideal for the vermicomposting.</P>

Biomanagement of sago-sludge using an earthworm, Lampito mauritii.

Banu, J Rajesh,Yeom, Ick Tae,Esakkiraj,Kumar, Naresh,Lee, Young Woo,Vallinayagam, S The Academy 2008 Journal of environmental biology Vol.29 No.5

<P>In the present study vermicomposting was carried out at three different concentrations of sago-sludge namely 50, 75 and 100% with an indigenous earthworm, Lampito mauritii for a period of 50 days. The fecundity of earthworm Lampito mauritii was found to be high in 50%. At the end of 50 days composting period. There were about 12 cocoons, 5 juveniles and 2 nonclitellates appeared at 50% sago-sludge concentration. The microbial analysis showed that after 40 days of composting their population stabilized and further increase in composting period did not increase their population size. Chemical analysis of Lampito mauritii worked substrates showed there is a step wise increase of nitrogen and phosphorus. The fold increase of phosphorus and nitrogen were found to be high for sago-sludge undergoing vermicomposting than the control. From the initial value of 1.8, 1.4 and 0.5 mg kg(-1) total nitrogen increased in a stepwise manner and reached a value of 5.8, 3.9 and 2.3 mg kg(-1), respectively for vermicomposting at 50, 75 and 100%. During composting the organic carbon decreased from its initial value of 56, 74 and 107 mg kg(-1) to 15, 25 and 58 mg kg(-1) for vermicomposting and 34, 45 and 72 mg kg(-1) for 50, 70 and 100% control, respectively. The results indicate that 50% and 75% concentration of sludge mixed with bedding material was ideal for the vermicomposting.</P>

Effect of Alum on Nitrification during Simultaneous Phosphorous Removal in Anoxic/Oxic Reactor

J. Rajesh Banu,Khac-Uan Do,S. Kaliappan,염익태 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.4

Phosphorus and nitrogen are the important eutrophication nutrients. They are removed in the anoxic/oxic reactor through simultaneous precipitation and biological nitrogen removal. The effect of alum a commonly used simultaneous precipitant on biological nitrification and denitrification are investigated in the present study. Simultaneous removal of phosphorus was carried out using the coagulant alum Al₂(SO₄)₃∙14H₂O at 2.2 mol ratio. Before the start of simultaneous precipitation the nitrification rate of the A/O reactor was found to be 0.05 g N-NH4+/g VSS/d. It starts to decrease with increase in coagulant dosage. The nitrification rate for alum dosage 97.13 mg/L was 0.38 g N- NH₄+/g VSS/d. There was no accumulation of nitrate in anoxic tank. The nitrogen removal efficiency of the reactor was affected and it fell from 88 to 78%. There was a slight decrease in effluent COD from 16~20 mg/L to 8~12 mg/L after the introduction of simultaneous precipitation into the reactor. The usage of alum as a simultaneous precipitant in the anoxic/oxic reactor was limited due to its inhibition on nitrification. Alum did not have any affect over denitrification process.

<i>Marsilea</i> spp.—A novel source of lignocellulosic biomass: Effect of solubilized lignin on anaerobic biodegradability and cost of energy products

Rajesh Banu, J.,Sugitha, S.,Kannah, R. Yukesh,Kavitha, S.,Yeom, Ick Tae Elsevier 2018 Bioresource technology Vol.255 No.-

<P><B>Abstract</B></P> <P>The present study concerns the liquefying potential of an unusual source of lignocellulosic biomass (<I>Marsilea</I> spp., water clover, an aquatic fern) during combinative pretreatment. The focus was on how the pretreatment affects the biodegradability, methane production, and profitability of thermochemical dispersion disintegration (TCDD) based on liquefaction and soluble lignin. The TCDD process was effective at 12,000 rpm and 11 min under the optimized thermochemical conditions (80 °C and pH 11). The results from biodegradability tests imply that 30% liquefaction was sufficient to achieve enhanced biodegradability of about 0.280 g-COD/g-COD. When biodegradability was >30% inhibition was observed (0.267 and 0.264 g-COD/g-COD at 35–40% liquefaction) due to higher soluble lignin release (4.53–4.95 g/L). Scalable studies revealed that achievement of 30% liquefaction was beneficial in terms of the energy and cost benefit ratios (0.956 and 1.02), when compared to other choices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel lignocellulosic biomass, <I>Marsilea quadrifolia</I> was exploited to get energy. </LI> <LI> First study to evaluate the effect of liquefaction and lignin on biodegradability. </LI> <LI> Energy spent to obtain 20–30% liquefaction was very low compared to others. </LI> <LI> Inhibition of biodegradability occured for samples with 35–40% liquefaction. </LI> <LI> Cost analysis reveals that achievement of 30% liquefaction was profitable. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effect of sludge pretreatment on the performance of anaerobic/ anoxic/ oxic membrane bioreactor treating domestic wastewater

Banu, J. Rajesh,Uan, D. K.,Kaliappan, S.,Yeom, I. T. Springer-Verlag 2011 International journal of environmental science and Vol.8 No.2

Enhancing biomethanation from dairy waste activated biomass using a novel EGTA mediated microwave disintegration

Rajesh Banu, J.,Eswari, A. Parvathy,Saratale, Ganesh Dattatraya,Uma Rani, R.,Kaliappan, S.,Yeom, Ick-Tae Elsevier 2018 Journal of environmental management Vol.223 No.-

<P><B>Abstract</B></P> <P>A novel approach to explore the impact of calcium specific chelant - Ethylene glycol tetra acetic acid (EGTA) on deflocculation followed by biomass disintegration using microwave (MW) was investigated. In the first phase of the study, the EGTA dosage of 0.012 g/g suspended solids (SS) was found to be optimal for disassociating the biomass. Subsequent disintegration of biomass in microwave (EGTA-MW) yielded a biomass lysis and solids reduction of about 39.7% and 30.5%. EGTA-MW disintegration reduces the amount of specific energy required to disintegrate the biomass from 18,900 kJ/kg TS to 13,500 kJ/kg TS, when compared to control. The impact of EGTA-MW disintegration on anaerobic digestion was also evident from its methane yield (235.3 mL/g VS) which was 36.2% higher than control. An economic assessment of this study provides a net profit of 8.48 €/ton in EGTA-MW and highly endorsed for biomass disintegration.</P> <P><B>Highlights</B></P> <P> <UL> <LI> EGTA mediated microwave disintegration is a novel pretreatment method. </LI> <LI> EGTA mediated deflocculation was effective at 0.012 g/g SS. </LI> <LI> At low SE input 13,500 kJ/kg TS, EGTA-MW achieved a biomass lysis of about 39.7%. </LI> <LI> High methane potential of about 235.3 mL/g VS in EGTA-MW was achieved. </LI> <LI> EGTA-MW was found to be a cost-effective approach with a net profit of 8.48 €/ton. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Disperser-induced bacterial disintegration of partially digested anaerobic sludge for efficient biomethane recovery

Banu, J. Rajesh,Kannah, R. Yukesh,Kavitha, S.,Gunasekaran, M.,Yeom, Ick Tae,Kumar, Gopalakrishnan Elsevier 2018 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.347 No.-

<P><B>Abstract</B></P> <P>The present study highlights the options to enhance the methane potential of partially digested anaerobic sludge using disperser-induced bacterial disintegration. Floc dispersion with no biomass disintegration was achieved at a disperser-specific energy input of 9.5 kJ/kg TS. The outcomes of both sole bacterial disintegration (S-BD) and disperser-induced bacterial disintegration (D-BD) were assessed in terms of changes in lysate, biopolymer release and increase in biodegradability and methane generation. A higher lysate solubilization of about 22.4% was achieved in D-BD compared to S-BD (11.3%), indicating the efficiency of floc dispersion prior to bacterial disintegration. The biochemical methane result implies that D-BD shows higher methane potential of 0. 279 gCOD/gCOD. Considering the overall outcome achieved in this study, disperser-induced bacterial disintegration is proved to be an effective disintegration process for enhanced biodegradation and higher methane production.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Disintegration of digested sludge is a promising technique for bioenergy generation. </LI> <LI> Floc dispersion was achieved at lesser disperser input energy of 9.5 kJ/kg TS. </LI> <LI> A higher lysate solubilization of 22.4% was achieved in floc dispersed sample. </LI> <LI> Biopolymer release of floc dispersed sludge was higher (1379.8 and 394.2 mg/L) </LI> <LI> Result of methane reveals the effect of floc dispersion prior to disintegration. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Two-Stage Anaerobic Treatment of DairyWastewater Using HUASB with PUF andPVC Carrier

염익태,J. Rajesh Banu,S. Kaliappan 한국생물공학회 2007 Biotechnology and Bioprocess Engineering Vol.12 No.3

In the present study, an attempt has been made to treat dairy wastewater entirely via anaerobic treatment over a period of 215 days, using two-stage Hybrid Upflow Anaerobic Sludge Blanket (HUASB) reactors, which offer the advantages associated both with fixed film and upflow sludge blanket treatments. A HUASB with polyurethane foam cubes was used for stage I, and a HUASB utilizing PVC-cut rings was used for stage II. The output from stage I was used as the input for stage II. The two-stage reactor was operated at an organic loading rate that varied from 10.7 to 21.4 kg COD m3/d for a period of 215 days, including the start-up period. The ideal organic loading rate for the two-stage reactor was 19.2 kg COD/m3/d. A further 21.4 kg COD m3/d increase in the organic loading rate resulted in the souring of the reactor function in stage I, which consequently reduced the overall reactor performance. Combined COD removal during the stable operation period (10.7 to 19.2 kg COD m3/d) occurred in a range between 97 and 99%. The methane content in the biogas varied from 65 to 70% in stage I, and from 63 to 66% in stage II. The two-stage anaerobic treatment using HUASB with PUF and PVC described in this work is expected to constitute a better alternative for the complete treatment of dairy wastewater than high-rate anaerobic, anaerobic/aerobic, and two-phase anaerobic treatment methods.