International Journal of Advance Engineering and Research Development

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1 Scientific Journal of Impact Factor (SJIF): 5.71 International Journal of Advance Engineering and Research Development Volume 5, Issue 04, April e-issn (O): p-issn (P): GRANULE DEVELOPMENT AND PERFORMANCE OF SAGO WASTEWATER FED UPFLOW ANAEROBIC SLUDGE FIXED-FILM REACTOR Nandhini N 1, Sheela R 2, Asha B 3 1 P.G Student, Department of Civil Engineering, Annamalai University, Annamalai Nagar, Tamilnadu. 2,3 Assistant professors, Department of Civil Engineering, Annamalai University, Annamalai Nagar, Tamilnadu. Abstract A laboratory scale Up-flow anaerobic sludge fixed film reactor with the working volume of litres at 28 C was started up and loaded to an Organic Loading Rate (OLR) of kg COD/m3/d. The results showed that the UASFF reactor has good performance in terms of COD removal at a Hydraulic Retention Time (HRT) of 24 hours with an OLR of kg COD/m 3 /d. The ph of the feed was maintained in the range of 6.8 to 8.3. The entire start up period was carried out for 21 days with a HRT of 24 hours. This methodology was designed to decrease the Hydraulic Retention Time (HRT) from 48 to 21 days. The removal efficiency of the Chemical Oxygen Demand (COD) were 40% and 90% on the 2 nd and 21 st day respectively. The goal of this present study is to shorten the start-up time of the treatment process as compared to UASBR. Keywords- Chemical Oxygen Demand, Hydraulic Retention Time, Microbial Consortium, Organic Loading Rate, Upflow Anaerobic Sludge Fixed Film Reactor. I. INTRODUCTION Anaerobic treatment for wastewater has been acquiring an extensive popularity when it is compared with the aerobic treatment. Comparatively the anaerobic treatment for wastewater is very cost effective and has low sludge production and biogas recovery was maximum. Anaerobic process is a biological process carried out in the absence of oxygen for the stabilization of organic materials by conversion to methane and inorganic end products such as carbon-dioxide and ammonia. The volumetric load (COD load per m³ active volume per day) in an anaerobic reactor is typically 5 to 10 times higher than aerobic wastewater treatment. Sludge growth in an anaerobic reactor is 4-5 times lower than in an aerobic system.(lettinga,1995; Metcalf & Eddy, 2003 ). If the anaerobic sludge is not fed, it will hibernate, which means longer periods without food can be spanned without excessive sludge mortality. The system will almost immediately become active after re-start. The encountered organic pollutant is converted into biogas with a high energetic value. Amongst, the upflow anaerobic sludge blanket reactor is considered as one of the most famous anaerobic processes, which has the ability of maintaining high biomass in the form of granulated sludge and accordingly to allow high rate reactor performance. (Lettinga and Holshoff 1991). A major trouble related with the UASB reactor is long period for granulation, it may take several months. Alteration of UASB process was required to control the existing deficiency (.Najafpour et.al., (2008). Some internal packing is used for maintaining the biomass in the UASB reactor is the suitable solution to solve the above mentioned problem. The packing medium present in the reactor which helps to increase the solid retention time. (Elmitwalli,T.A et.al., (2007). The UASB reactor has been successfully used for treating various kinds of industrial waste water (A.A.L.Zinatizadeh et.al., (2006), Seyyed Mohammed Emadian et.al., (2015), G.D.Najafpour et.al.,(2008), Nazila Samimi Tehrani et.al., (2015), Ezzat abdel shafi et.al.,(2009). The process of gathering of biomass (Cells of micro-organisms) and retention in biomass systems are increased by attachment to a fixed medium. In the fixed film process, micro organisms are immobilized on a support surface, forming bio-films.(andrew M.Jenkins et.al., (2012) Substrates in the wastewater are absorbed into the film and gradually degraded by the micro-organisms. The attached growth process is more stable than suspended growth process when the waste water has considerable fluctuations in flow rate and concentrations. The utilization of fixed films for waste water treatment process has been increasingly considered due to inherent advantages over suspended growth system such as simplicity of construction and elimination of mechanical mixing. (Bharati Sunil Shete et.al., (2014) The main objective of this work was to look into the start up process performance of a laboratory scale UASFF inoculated with digested slurry, which was collected from an active anaerobic wastewater treatment plant at Annamalai All rights Reserved 398

2 II. EXPERIMENTAL METHODOLOGY Hybrid Reactor Configuration The UASFF reactor is the hybrid anaerobic reactor which is the combination of UASB and UFF reactor. The lower part of the UASFF reactor is the UASB portion where flocculants and granular sludge are formed. Then the fixed film portion is present above the UASB portion where internal packing is present. A laboratory scale UASFF reactor was made of a Plexi glass column with an internal diameter of 15cm and a height of180cm. The total volume of the reactor was 30,386 ml and the working volume was 28,266ml (excluding head space). The column consists of three compartments; bottom, middle and top. The bottom part of the column, with a height of 111cm was operated as a fixed film reactor. The top part of the bioreactor served as a gas-liquid-solid separator. The middle section of the column was packed with packing medium. The purpose of the top section (i.e. the gas-liquid-solid separator) of the reactor was to allow separation of the biogas and washed out solids from the liquid phase. An inverted funnel shaped gas separator was used to conduct the biogas to the gas collector tank. A gas sampling port was provided for the determination of biogas composition. The physical feature of the experimental set up was shown in Table 1.A variable speed peristaltic pump (PP-30) was used to control feed rate. The schematic of the laboratory scale experimental set up was shown in Figure 1. P.P- Peristaltic Pump Figure 1. Schematic of the Experimental set up Table 1: Physical Features of Experimental Setup Reactor Configuration Dimensions Total height of the reactor 180cm Effective height of the reactor 168cm Effective volume of the reactor 28 litres Effective diameter of the reactor 15cm Diameter of the GLSS top 3cm Diameter of the GLSS bottom 12cm Total height of the GLSS 10cm Diameter of Influent & Effluent pipe 1cm Peristaltic pump All rights Reserved 399

3 Packing medium Fujinospirals with the size of 26 mm was used a packing medium in the fixed film portion of the UASFF reactor. The specific surface area of the packing material was 500 m 2 /m 3 with a void space of 87%. The structure of the fujinospirals is shown in the Figure 2. Figure 2. Packing medium Analytical Method The influent and effluent samples were collected for every 24 hours and were analysed immediately as per the procedure given in Standard Methods (APHA 2016). III. RESULT AND DISCUSSIONS Acclimation and Process stability During the granulation process of anaerobic reactor, the biomass is acclimatized to new environmental conditions.(alkarimia R et.al., (2011). The inoculums source was granular sludge taken from the active biomass plant located at Faculty of Agriculture, Annamalai University, Annamalai Nagar. The granules were passed through a screening to remove debris. Establishment of the microbial consortium is the overall objective of the start up process of UASFF reactor. Performance of the reactor The influent and effluent samples from the reactor were collected on the daily basis and were analyzed immediately. Initially the influent feed of wastewater which are collected from the treatment facilities at Annamalai University. The low initial loading rate was recommended for the successful start-up of UASFF reactor. A low initial organic loading rate was beneficial for the growth of anaerobic active sludge, due to low COD organic loading resulting in low production of gas rate and low waste water up-flow velocity. The start up process of UASFF have been well presented in the literature (Najafpour et.al., 2006). The start-up period is considered as the period taken for stable operation to be achieved. In addition, operating temperature is prominent during start-up. In this work, the treatment operation was carried out in the laboratory where the operating temperature varied from 25º C 35º C (mesophilic range). The start-up stage of the process was began by continuous feeding of the reactor with an initial influent COD concentration of 480 mg/l with a HRT of 24 h and consequently organic loading rate of 0.551Kg COD/m 3 /day which is remarkably a low value. The COD removal rate during first two days was low in the range of 30% to 40%. The low efficiency in removal at the beginning of the process is due to the biomass adaptation in the new environment. The reactor achieved at steady state conditions during the period of 18 th day to 21 st day with a COD removal efficiency of 90%.(Figure. 2) It is difficult to maintain the effective number of useful microorganisms in the system (BAL A.S et.al., All rights Reserved 400

4 Figure 2: Start up Performance of UASFF reactor The ph is an important factor to control the digestion process in the anaerobic reactors. The methane forming microorganisms can survive in a condition with ph values ranging between 6.6 and 7.6 (Ritmann and Mc cardy P.L 2001 )., although stability may be achieved in the formation of methane over a range of 6.0 to 8.0. ph values below 6.0 and 8.3 should be avoided, as they can inhibit the methane forming microorganisms (Chernicharo C.A.L., 2007). Variations in ph of effluent from the reactor during the start up stages are shown in Figure. 3. Also the ph of the reactor was comparatively stable by varying from 6.8 to 8.3 which are well suited for methanogenic activities. This range of ph indicates that the reactor had sufficient alkanity to neutralize the organic acids delevevered from the hydrolysis as well as the acidogenesis stages. Figure.3: Variations in ph during start up process IV. CONCLUSIONS The purpose of the start-up of anaerobic bioreactors is to grow, build up and retain a sufficient concentration of active and well balanced biomass. It is concluded from the present research work that a self inoculated UASFF reactor with institutional sewage achieved the maximum COD removal efficiency in 21 days. This reactor was found to be very successful for the COD removal efficiency of around 90% during startup with an OLR of 0.551kg COD/m 3 /day. Also maintained a suitable and stable ph within the reactor for ensuring efficient methanogenic All rights Reserved 401

5 V. REFERENCES [1] Alkarimia R, Mahat S.B., Yuzir A., Fadhil M and Chelliapan Performance of an innovative multi stage anaerobic reactor during start-up period, African Journal of Biotechnology, Vol.10, no.54, pp [2] Andrew M.Jenkins, E.I. and Darrell Sanders, P.E. 2012, Introduction to Fixed-Film Bio-Reactors for Decentralized Wastewater Treatment Professional Development Series, By [3] APHA Standards for Water and Waste water Testing APHA. New York. U.S.A. [4] Bal, A.S. and Dhagat, N.N Up-flow anaerobic sludge blanket reactor A review, Indian, J. Environ. Health. 43(2), [5] Bharati Sunil Shete and N.P. Shinkar Fixed Film Fixed Bed Reactor-Low Cost Approach, International Journal of Civil, Structural,Environmental and Infrasstructure Engineering Research and Development. 4(4), pp [6] Chernicharo, C.A.L.,2007. Anaerobic reactors biological waste water treatment series.v.4, IWA publications, London. [7] Elmitwalli,T.A. and R. Otterpohl, Anaerobic biodegradability and treatment of grey water in upflow anaerobic sludge blanket (UASB) reactor,water Research, 41: [8] Ezzat Abdel Shafi, Hisham S.Abdel Halim, Mohamed H.Mostafa, and Mohamed Nazih Cost Effective Wastewater Treatment Processes: Anaerobic Domestic Wastewater treatment using Fixed Film Reactor as a Low cost Treatment alternative. IWTC [9] Lettinga.G and L.W. Hulshoff Pol UASB- Process Design for Various types of Wastewaters, 24(8) [10] Lettinga G. Antonie Van Leeuwenhoek Anaerobic Digestion and Wastewater Treatment systems. 67(1):3-28. [11] Metcalf and eddy (2003) Waste water Engineering Treatment and Reuse. 4thEdition, McGraw-Hill, New York. [12] Najafpour, G.D., Hashemiyeh, B.A., Asadi, M. And Ghasemi, M.B., Biological treatment of Diary waste water in an upflow anaerobic sludge-fixed film bioreactor.am. Eurasian J..Agric. Environ.Sci, 4(2),pp [13] Nazila Samimi Tehrani, Ghasem D. Najafpour, Mosthafa Rahimnejad, Hossein Attar Performance of Upflow Anaerobic Sludge Fixed Film Bioreactor for the Treatment of High Organic Load and Biogas Production of Cheese whey Wastewater. 21(2) [14] Ritmann,B.E., Mc Carty, P.L.,2001. Environmental Biotechnology; Principles and applications. Mc Graw- Hill International edition, New York. [15] Seyyed Mohamad Emadian., Mostafa Rahimnejad, morteza Hosseini and behnam khoshandam Investigation on Upflow anaerobic sludge fixed film reactor for treating low strength bilge water of Caspian sea ships. Journal of Environmental Health Science & Engineering [16] Yamuguchi, T., Harada, H., Treatment of sewage by a UASB reactor treating a wastewater containing high strength sulphate. Water Research, 33(14), pp [17] Zinatizadeh, A.A.L., Mohamed, A.R., Abdullah, A.Z., Mashitah, M.D., Isa, M.H. and Najafpour, G.D., Process modelling and analysis of palm oil mill effluent treatment in an up-flow anaerobic sludge fixed film bioreactor using response surface methodology (RSM). Water Research, 40(17), All rights Reserved 402