Effect of cod loading rate on an upflow anaerobic sludge blanket reactor during anaerobic digestion of palm oil mill effluent with butyrate /

Palm oil Mill Effluent (POME) with concentrated butyrate was treated in a 4.5 l upflow anaerobic sludge blanket reactor (UASBR), run over a range of influent concentrations (16.5–46.0 g-COD l−1), chemical oxygen demand (COD) loading rates (1.5–11.5 g-CODl−1d−1) and 11–4 days hydraulic retention time (HRT) at 37 °C by maintaining pH between 6.5–7.5. The process consistently removed 97–99% of COD at loading rates up to 1.5–4.8 g-COD l−1d−1 by varying HRT (11–7.2 days). Butyrate is an important intermediate in the anaerobic degradation of organic matter. In sulphate-depleted environment, butyrate in POME (BOD/COD ratio of 0.5) is β-oxidised to acetate and hydrogen, by obligate proton reducers in syntrophic association with hydrogen utilizing methanogens. The conversion of acetate to methane appeared to be rate limiting step. Maximum biogas (20.17 ll−1d−1) and methane production (16.2 ll−1d−1) were obtained at COD loading rate of 4.80 gl−1d−1and HRT of 7.2 days. The biogas and methane production were higher in the presence of butyrate compared to control. The methane content of the biogas was in the range of 70–80% throughout the study while in control it was 60–65%. Finding of this study clearly indicates the successful treatment of POME with butyrate in UASBR. Santrauka Palmių aliejaus gamybinės nuotekos (POME) su koncentruotu butiratu buvo apdorotos 4,5 l talpos aukštyn tekančio aerobinio dumblo plokšteliniame reaktoriuje (UASBR). Nuotekos tekėjo įvairių koncentracijų (16,5–46,0 g – ChDS 1−1), cheminio deguonies suvartojimo (ChDS) normos (1,5–11,5 g – ChDS 1−1d.−1). Hidraulinio sulaikymo trukmė (HRT) nuo 11 iki 4 dienų, kai temperatūra 37 °C, pH palaikant 6,5–7,5. Vykstant procesui nuolat buvo pašalinama 97–99% ChD, kai tiekimo ir pakrovimo sparta 1,5–4,8 g – ChDS 1−1d.−1 kintant HRT(11–7,2 d.). Butiratas yra svarbus tarpininkas organinių medžiagų anaerobinio skilimo procese. Sulfatas iš aplinkos, butiratas iš POME (BDS/ChDS santykis 0,5) yra acetato ir vandenilio β oksidatoriai, priverčiantys protonų reducentus sintrofinės sąveikos su vandeniliu metu utilizuoti metanogenus. Acetato virtimas metanu pasirodė esąs greitį ribojantis veiksnys. Daugiausia biodujų (20,17 l 1−1 d.−1) ir metano (16,2 l 1−1 d.−1) susidarė tada, kai suvartojamo ChD tiekimo greitis buvo 4,80 g 1−1d.−1, o HRT – 7,2 dienos. Daugiau biodujų ir metano susidarė dalyvaujant butiratui, palyginti su kontroliniu pavyzdžiu. Biodujose metano kiekis tyrimo metu svyravo 70–80%, o kontroliniame buvo 60–65%. Šis tyrimas aiškiai parodė, kad POME su butiratu UASBreaktoriuje apdorojamas sėkmingai. Reikšminiai žodžiai: anaerobinis skilimas, palmių aliejaus gamybinės nuotekos, butiratas, acetatas,  UASB reaktoriu

Enhanced anaerobic co-digestion of food waste and solid poultry slaughterhouse waste using fixed bed digester : Performance and energy recovery

This study investigated the effects of organic loading rate (OLR) for anaerobic co-digestion (AcoD) of food waste (FW) and solid poultry slaughterhouse waste (SPSW) was performed in a fixed bed digester (FBD) at controlled pH to improve the methane production not fully discovered. Anaerobic co-digestion FW and SPSW were started up for the first time by gradually increasing OLR. At steady state, the FBD-AcoD reactor at OLR of 23.5 g COD/L/d the methane production was 7.8 L/L/d. Which achieved the highest OLR of 23.5 g COD/L, on the other hand when at OLR of 25.5 to 27.5 g COD/L the digester appeared inhibited and showed low performance in methane yields due to the accumulation of volatile fatty acids (VFAs) and long chain fatty acids (LCFAs). Methanosaeta and Methanosarcina were dominant over the acidogenic in the digester boosting the FBD-AcoD system to counter the acid effect. The removals of TS and VS around 79% and 76% on a continuous basis with a waste mixing of SPSW 18.5% and OLR of up to 23.5 g COD/L could biogas production 81 g COD/L/d. The FBD-AcoD system produces bioenergy of 875.3 Kj/g COD and the total investment energy utilized in the system was 8.51 Kj/g COD respectively

Evaluation of the Bio-Kinetics of Cement Kiln Dust In An Upflow Anaerobic Sludge Blanket Reactor for Treatment of Palm Oil Mill Effluent As A Function of Hydraulic Retention Time

In this paper we operated an upflow anaerobic sludge blanket reactor (UASBR) continuously at 35 °C in order to observe the effects of varying the hydraulic retention time (HRT) from 3.5 to 34.5 d and varying the organic loading rate (OLR) from 1.5 to 46 kg COD m−3 d−1. The pH of the digester improved, which we varied from 1.5 to 14.5 g L−1 CaO-CKD, a range pH 7.5. A high COD degradation rate of 97% and mixed liquor suspended solids (MLVSS) of 99,000 mg L−1 were achieved at an HRT of 24.5 d. The maximum methane yield was 0.346 l CH4/g CODremoved. A CO2 reduction of 87% was obtained at an OLR of 26.5 (r = 0.99). The optimum conditions for digestion of the palm oil mill effluent were determined by studying the bio-kinetics of granulation. The growth yield (YG) was 1.45 g VSS/g CODremoved day; the specific biomass decay (b) was 0.056; the specific biomass growth rate (μmax) was 0.988 d−1; the saturation constant (Ks) was 460; and the critical retention time (Θc) was 2.464 d−1. With a feed flow rate (QF) of 1.65 l/d, the upflow velocity (Vup) was 0.6 m/h, and for a QF of 2.45 l/d, Vup was 0.75 m/h

Enhanced Anaerobic Degradation Of Palm Oil Mill Effluent Using Butyrate, Cao-Ckd And Denitrifying Sulfide Removal

During this research three experiments were performed. In the first experiment Palm oil Mill Effluent (POME) with concentrated butyrate was treated in a 4.5 L upflow anaerobic sludge blanket reactor (UASBR), run over a range of influent concentrations (16.5-46.0 g-COD L-1), chemical oxygen demand (COD) loading rates (1.5-11.5 g CODL-1 d-1) and 11-4 days hydraulic retention time (HRT) at 37 °C by maintaining pH between 6.5-7.5. The process consistently removed 9799% of COD at loading rates up to 1.5-4.8 g COD L -1 d -1 by varying HRT (11-7.2 days). The conversion of acetate to methane appeared to be rate limiting step. Maximum biogas (20.17 LL -1 d -1) and methane production (16.2 LL) were obtained at COD loading rate of 4.80 gL -1 d -1 and HRT of 7.2 days. The biogas and methane production were higher in the presence of butyrate compared to control. The methane content of the biogas was in the range of 70-80% throughout the study while in control it was 60-65%. Finding of this study clearly indicates the succesful treatment of POME with butyrate in UASBR. In the second experiment, calcium oxide-cement kiln dust (CaO-CKD) was used to enhance the granulation process. The granulation process in POME using CaO-CKD provided an attractive and cost effective treatment option. In this study the efficiency of CaOCKD at doses of 1.5 to 20 gL -1 was tested in batch experiments and found that 10 g of CaO/L caused the greatest degradation of VFA, butyrate and acetate. An upflow anaerobic sludge blanket (UASB) reactor was operated continuously at 35 ºC for 150 days to investigate the effect of CaO-CKD on sludge granulation and methanogenesis during start-up. The treatment of POME emphasized the influence of varying organic loading rates (OLR). Up to 94.9% of COD was removed when the reactor was fed with the 15.5 to 65.5 g-COD gL at an OLR of 4.5-12.5 Kg-CODm-3 d -1, suggesting the feasibility of using CaO in an UASB process to treat POME. The ratio of volatile solids/total solids (VS/TS) and volatile fatty acids in the anaerobic sludge in the UASB reactor decreased significantly after long-term operation due to the precipitation of calcium carbonate in the granules. Granulation and methanogenesis decreased with an increase in the influent CaO-CKD concentration. In the third experiment, the inhibitory effects of 134.82-771.9 mgL -1 d -1 of sulfide loading rate (SLR) and 58.79-337.56 mgL -1 d -1 -1 of nitrate loading rate (NLR) on methanogenesis were investigated in a mixed methanogenic culture using butyrate as carbon source. A novel strategy was adopted to cultivate mature granules using anaerobic sludge of palm oil mill effluent (POME) as seed sludge, incubated in DSR medium to acclimate the denitrifiers. Biological denitrification was used to eliminate carbon, nitrogen and sulfur in an anaerobic granular bed reactor (AGBR) of 4.5 L by varying hydraulic retention time from 35.6-6.2 days. The maximum nitrate and sulfide removal efficiencies were observed up to SLR and NLR of 188.42 mgL -1 d -1 and 82.39 mgL -1 d -1 respectively. Maximum VFA removal of 82% was obtained on SLR and NLR of 230 mgL -1 d -1 and 100.62 mgL -1 d-1

Effect of cod loading rate on an upflow anaerobic sludge blanket reactor during anaerobic digestion of palm oil mill effluent with butyrate

Palm oil Mill Effluent (POME) with concentrated butyrate was treated in a 4.5 l upflow anaerobic sludge blanket reactor (UASBR), run over a range of influent concentrations (16.5–46.0 g-COD l−1), chemical oxygen demand (COD) loading rates (1.5–11.5 g-CODl−1d−1) and 11–4 days hydraulic retention time (HRT) at 37 °C by maintaining pH between 6.5–7.5. The process consistently removed 97–99% of COD at loading rates up to 1.5–4.8 g-COD l−1d−1 by varying HRT (11–7.2 days). Butyrate is an important intermediate in the anaerobic degradation of organic matter. In sulphate-depleted environment, butyrate in POME (BOD/COD ratio of 0.5) is β-oxidised to acetate and hydrogen, by obligate proton reducers in syntrophic association with hydrogen utilizing methanogens. The conversion of acetate to methane appeared to be rate limiting step. Maximum biogas (20.17 ll−1d−1) and methane production (16.2 ll−1d−1) were obtained at COD loading rate of 4.80 gl−1d−1 and HRT of 7.2 days. The biogas and methane production were higher in the presence of butyrate compared to control. The methane content of the biogas was in the range of 70–80% throughout the study while in control it was 60–65%. Finding of this study clearly indicates the successful treatment of POME with butyrate in UASBR

Bioenergy from anaerobic degradation of lipids in palm oil mill effluent

Fossil fuels are the lifeblood of our society and for many others around the world. The environmental pollution due to the use of fossil fuels as well as their gradual depletion make it necessary to find alternative energy and chemical sources that are environmentally friendly and renewable. Palm oil mill effluent (POME), a strong wastewater from palm oil mills, has been identified as a potential source to generate renewable bioenergies through anaerobic digestion. Thus, it has received considerable attention as feedstock for producing various value added products such as methane gas, bio-plastic, organic acids, bio-compost, activated carbon, and animal feedstock. Lipids are one of the major organic pollutants in POME. Furthermore, waste lipids are ideal potential substrates for biogas production, since theoretically more methane can be produced, when compared with proteins or carbohydrates. The objective of this review paper is to disscuss the microbial communities involved in the anaerobic degradation of long chain fatty acid and bioenergies and by-products from POME. With these options (Renewable and sustainable bioenergies) we can help phase out our dependency on fossil fuels and find clean, efficient, sources of power

Role of calcium oxide in sludge granulation and methanogenesis for the treatment of palm oil mill effluent using UASB reactor

The granulation process in palm oil mill effluent using calcium oxide-cement kiln dust (CaO–CKD) provides an attractive and cost effective treatment option. In this study the efficiency of CaO–CKD at doses of 1.5–20 g/l was tested in batch experiments and found that 10 g of CaO/l caused the greatest degradation of VFA, butyrate and acetate. An upflow anaerobic sludge blanket (UASB) reactor was operated continuously at 35 °C for 150 days to investigate the effect of CaO–CKD on sludge granulation and methanogenesis during start-up. The treatment of POME emphasized the influence of varying organic loading rates (OLR). Up to 94.9% of COD was removed when the reactor was fed with the 15.5–65.5 g-COD g/l at an OLR of 4.5–12.5 kg-COD/m3 d, suggesting the feasibility of using CaO in an UASB process to treat POME. The ratio of volatile solids/total solids (VS/TS) and volatile fatty acids in the anaerobic sludge in the UASB reactor decreased significantly after long-term operation due to the precipitation of calcium carbonate in the granules. Granulation and methanogenesis decreased with an increase in the influent CaO–CKD concentration

Phytosequestration of Metals in Selected Plants Growing on a Contaminated Okhla Industrial Areas, Okhla, New Delhi, India

Contamination of metal ions in soil and water represents more pressing threats to resources as well as human health. The present research was carried out to screen the phytosequester plants growing in industrial waste- and wastewater-affected industrial areas of Okhla, New Delhi, India. Accumulation trend of metal Fe, Zn, Cu, Cr, Pb, Cd, Hg, and As from soil and wastewater by plants were collected for study. Among aquatic plants Hydrilla verticillata, Marsilea quadrifolia, and Ipomea aquatica were found to be highest metals accumulator, Eclipta alba and Sesbania cannabina among terrestrial plant were highest accumulator of metals. Among the algal spp. Spirulina platensis and Phormidium papyraceum were the most efficient in accumulating Cd and Hg. The maximum bioconcentration factor (BCF) was recorded in Hygroryza aristata for the metals (Hg, Cd) in M. quadrifolia (Cd, Cr), in E. alba (Cr, Cu), and in S. platensis (Hg, Pb). However, the translocation factor (TF) of metals was found more in M. quadrifolia followed by I. aquatica than other plants. Among all the plants, H. verticillata showed high TF and low BCF values for toxic metals (Pb, Cr) and was suitable for phytostabilization of these metals. Our study showed that native plant species growing on contaminated sites may have a potential of phytosequestration of these metals

Integrated application of upflow anaerobic sludge blanket reactor for the treatment of wastewaters

The UASB process among other treatment methods has been recognized as a core method of an advanced technology for environmental protection. This paper highlights the treatment of seven types of wastewaters i.e. palm oil mill effluent (POME), distillery wastewater, slaughterhouse wastewater, piggery wastewater, dairy wastewater, fishery wastewater and municipal wastewater (black and gray) by UASB process. The purpose of this study is to explore the pollution load of these wastewaters and their treatment potential use in upflow anaerobic sludge blanket process. The general characterization of wastewater, treatment in UASB reactor with operational parameters and reactor performance in terms of COD removal and biogas production are thoroughly discussed in the paper. The concrete data illustrates the reactor configuration, thus giving maximum awareness about upflow anaerobic sludge blanket reactor for further research. The future aspects for research needs are also outlined