Hydrogen as a quick indicator of organic shock loading in UASB

2000 ◽  
Vol 42 (3-4) ◽  
pp. 43-50 ◽  
Author(s):  
Y.-H. Huang ◽  
G.-H. Huang ◽  
S. Chou ◽  
S.-S. Cheng
Keyword(s):  
Ethylene Glycol ◽  
Continuous Flow ◽  
Shock Loading ◽  
Biogas Production ◽  
H2 Production ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Flow Mode ◽  
Raw Wastewater

This study investigates the influence of organic shock loading on H2 production in an upflow anaerobic sludge bed (UASB) reactor. An esterification wastewater produced from a polyethylene terephthalate (PET) manufacturing plant was applied; the major organic pollutants are ethylene glycol and acetaldehyde. Experiments of two influent modes were performed here: a continuous-flow mode with a step input of shock loading and a batch mode with a pulse input of shock loading. Results of the continuous-flow experiments indicate that biogas production parameters such as H2 concentration and biogas production rate are more sensitive than water quality parameters such as pH, ORP, COD and TOC. In particular, H2, increasing by 140% within 1 hour, is a very important index upon the organic shock loading. It changes from 120 ppm to over 600 ppm as the organic loading rate increases from 4.4 to 13.2 kgCOD/m3·day through 4 hours of shock loading. Experiments of the batch shock loading with different pulse dosagesof ethylene glycol, acetaldehyde and the raw wastewater were also investigated. The amount of H2 production increased in proportion to an increase of organic load. Furthermore, the sequence of H2 production among the three types of shock loading is acetaldehyde> ethylene glycol> raw wastewater. To sum up, H2 shows a faster response rate than the other parameters. Therefore, H2 can be adopted as an important parameter for organic shock loading in UASB.

scholarly journals The Concept of Wastes to Energy Using Sugary Wastes

2012 ◽  
Vol 9 ◽  
pp. 57-62
Author(s):  
Fiza Sarwar ◽  
Wajeeha Malik ◽  
Muhammad Salman Ahmed ◽  
Harja Shahid
Keyword(s):  
Volatile Fatty Acids ◽  
Loading Rate ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Loading Rates ◽  
Sugar Mills ◽  
Anaerobic Sludge Blanket

Abstract: This study was designed using actual effluent from the sugary mills in an Up-flow Anaerobic Sludge Blanket (UASB) Reactor to evaluate treatability performance. The reactor was started-up in step-wise loading rates beginning from 0.05kg carbon oxygen demand (COD)/m3-day to 3.50kg-COD/m3-day. The hydraulic retention time (HRT) was slowly decreased from 96 hrs to eight hrs. It was observed that the removal efficiency of COD of more than 73% can be easily achieved at an HRT of more than 16 hours corresponding to an average organic loading rate (OLR) of 3.0kg-COD/m3-day, at neutral pH and constant temperature of 29°C. The average VFAs (volatile fatty acids) and biogas production was observed as 560mg/L and 1.6L/g-CODrem-d, respectively. The average methane composition was estimated as 62%. The results of this study suggest that the treatment of sugar mills effluent with the anaerobic technology seems to be more reliable, effective and economical.DOI: http://dx.doi.org/10.3126/hn.v9i0.7075 Hydro Nepal Vol.9 July 2011 57-62

Treatment of a chocolate industry wastewater in a pilot-scale low-temperature UASB reactor operated at short hydraulic and sludge retention time

2013 ◽  
Vol 67 (6) ◽  
pp. 1353-1361 ◽  
Author(s):  
M. Esparza-Soto ◽  
O. Arzate-Archundia ◽  
C. Solís-Morelos ◽  
C. Fall
Keyword(s):  
Low Temperature ◽  
Retention Time ◽  
Biogas Production ◽  
Pilot Scale ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Processing Industry ◽  
Sludge Retention Time ◽  
Industry Wastewater

The aim of this work was to evaluate the performance of a 244-L pilot-scale upflow anaerobic sludge blanket (UASB) reactor during the treatment of chocolate-processing industry wastewater under low-temperature conditions (18 ± 0.6 °C) for approximately 250 d. The applied organic loading rate (OLR) was varied between 4 and 7 kg/m3/d by varying the influent soluble chemical oxygen demand (CODsol), while keeping the hydraulic retention time constant (6.4 ± 0.3 h). The CODsol removal efficiency was low (59–78%). The measured biogas production increased from 240 ± 54 to 431 ± 61 L/d during the experiments. A significant linear correlation between the measured biogas production and removed OLR indicated that 81.69 L of biogas were produced per kg/m3 of CODsol removed. Low average reactor volatile suspended solids (VSS) (2,700–4,800 mg/L) and high effluent VSS (177–313 mg/L) were derived in a short sludge retention time (SRT) (4.9 d). The calculated SRT was shorter than those reported in the literature, but did not affect the reactor's performance. Average sludge yield was 0.20 kg-VSS/kg-CODsol. The low-temperature anaerobic treatment was a good option for the pre-treatment of chocolate-processing industry wastewater.

Comparison of start-up of an upflow anaerobic sludge blanket reactor and a polyurethane carrier reactor

1996 ◽  
Vol 34 (5-6) ◽  
pp. 509-515 ◽  
Author(s):  
Huub J. Gijzen ◽  
Frank Kansiime
Keyword(s):  
Volatile Fatty Acids ◽  
Biogas Production ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Operational Conditions ◽  
Start Up ◽  
And Performance ◽  
Anaerobic Sludge Blanket

The start-up and performance of an Upflow Anaerobic Sludge Blanket (UASB) reactor and a Polyurethane Carrier Reactor (PCR) was investigated under similar operational conditions. The presence of polyurethane cubes as a carrier material in the PCR resulted in fast reactor start-up due to quick immobilization of methanogenic associations. Start-up of the UASB was slower compared to the PCR, which was mainly reflected in a lower biogas production and acetate degradation efficiency. However, when enough biomass had accumulated in the UASB reactor after 15 weeks of operation, the performance of the two reactors was almost the same in terms of biogas production and volatile fatty acids degradation. Efficient VFA degradation (about 90%) and biogas production (5.2 l/l.d) were achieved at an organic loading rate of 13.2 g/l.d) and HRT of 6 h. When hydraulic retention time was subsequently reduced from 6 to 2 h, the performance of the UASB reactor was better than that of the PCR. The inferior performance of the PCR may have been attributed to channelling of the influent in the reactor at high liquid flow rate.

scholarly journals Influence of Pre-Hydrolysis on Sewage Treatment in an Up-Flow Anaerobic Sludge BLANKET (UASB) Reactor: A Review

Water ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 372 ◽  
Author(s):  
Rajinikanth Rajagopal ◽  
Mahbuboor Choudhury ◽  
Nawrin Anwar ◽  
Bernard Goyette ◽  
Md. Rahaman
Keyword(s):  
Suspended Solids ◽  
Biogas Production ◽  
Sewage Treatment ◽  
Oxygen Demand ◽  
High Rate ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Two Phase ◽  
Anaerobic Sludge Blanket

The up-flow anaerobic sludge blanket (UASB) process has emerged as a promising high-rate anaerobic digestion technology for the treatment of low- to high-strength soluble and complex wastewaters. Sewage, a complex wastewater, contains 30–70% particulate chemical oxygen demand (CODP). These particulate organics degrade at a slower rate than the soluble organics found in sewage. Accumulation of non-degraded suspended solids can lead to a reduction of active biomass in the reactor and hence a deterioration in its performance in terms of acid accumulation and poor biogas production. Hydrolysis of the CODP in sewage prior to UASB reactor will ensure an increased organic loading rate and better UASB performance. While single-stage UASB reactors have been studied extensively, the two-phase full-scale treatment approach (i.e., a hydrolysis unit followed by an UASB reactor) has still not yet been commercialized worldwide. The concept of treating sewage containing particulate organics via a two-phase approach involves first hydrolyzing and acidifying the volatile suspended solids without losing carbon (as methane) in the first reactor and then treating the soluble sewage in the UASB reactor. This work reviews the available literature to outline critical findings related to the treatment of sewage with and without hydrolysis before the UASB reactor.

scholarly journals Usage of UASB Reactor to Assess Feasibility of Treatment of Paper Mill Effluent

2011 ◽  
Vol 28 (2) ◽  
pp. 103
Author(s):  
A Arshad ◽  
N.H Hashim ◽  
N Ghazala
Keyword(s):  
Activated Carbon ◽  
Removal Efficiency ◽  
Biogas Production ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Paper Mills ◽  
Neutral Ph ◽  
Kinetic Coefficients ◽  
Mesophilic Temperature

Upflow anaerobic sludge blanket (UASB) reactors R-I and R-II, each with an effective volume of 6.0 l were used to study the treatability of actual effluent obtained from paper mills at a mesophilic temperature and neutral pH. Methanol, as a source of an easily biodegradable substance along with activated carbon of effective size 1.5 mm–2.5 mm were added to the reactor R-I to a total depth of 12 cm to evaluate its efficiency. The pH of both the reactors were kept constant at neutral by adding an external buffer solution of 0.03 M NaHCO3 with the feed solution. It was observed that corresponding to an organic loading rate of 3.5 kg-COD/m3-day, the overall chemical oxygen demand (COD) removal efficiency of the reactors R-I and R-II were 88% and 64%, respectively. The absorbable organic halides removal efficiency was observed to be 72% and 47% for reactorR-I and R-II, respectively. During the study it was however observed that, the treatability efficiency of reactor R-I was comparatively better but the amount of its biogas production was slightly lower than that of R-II. The average biogas production in reactors R-I and R-II during the course of study was observed as 0.33 l/g-CODremoved and 0.42 l/g-CODremoved respectively, with a mean methane composition of 58%–61% in both the reactors. Kinetic coefficients of k, Ks, Y and kd were determined to be 0.7 g-TOC/g-VSS.d, 0.30 g-TOC/l, 0.26 g-VSS/g-TOC and 0.02 day–1 respectively, based on the results obtained from reactor R-I. The results of this study showed that the use of methanol andan activated carbon in a UASB reactor to anaerobically digest the paper mills effluent at a mesophilic temperature and a neutral pH reactor was quite a feasible and viable technique. 

Nitrite reduction and methanogenesis in a single-stage UASB reactor

2015 ◽  
Vol 72 (12) ◽  
pp. 2236-2242 ◽  
Author(s):  
L. I. Borges ◽  
C. M. López-Vazquez ◽  
H. García ◽  
J. B. van Lier
Keyword(s):  
Domestic Wastewater ◽  
High Strength ◽  
Single Stage ◽  
Nitrite Reduction ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
N Removal

In this study, nitrite reduction and methanogenesis in a single-stage upflow anaerobic sludge blanket (UASB) reactor was investigated, using high-strength synthetic domestic wastewater as substrate. To assess long-term effects and evaluate the mechanisms that allow successful nitrite reduction and methanogenesis in a single-stage UASB, sludge was exposed to relatively high nitrite loading rates (315 ± 13 mgNO2−-N/(l.d)), using a chemical oxygen demand (COD) to nitrogen ratio of 18 gCOD/gNO2−-N, and an organic loading rate of 5.4 ± 0.2 gCOD/(l.d). In parallel, the effects of sludge morphology on methanogenesis inhibition were studied by performing short-term batch activity tests at different COD/NO2−-N ratios with anaerobic sludge samples. In long-term tests, denitrification was practically complete and COD removal efficiency did not change significantly after nitrite addition. Furthermore, methane production only decreased by 13%, agreeing with the reducing equivalents requirement for complete NO2− reduction to N2. Apparently, the spatial separation of denitrification and methanogenesis zones inside the UASB reactor allowed nitrite reduction and methanogenesis to occur at the same moment. Batch tests showed that granules seem to protect methanogens from nitrite inhibition, probably due to transport limitations. Combined COD and N removal via nitrite in a single-stage UASB reactor could be a feasible technology to treat high-strength domestic wastewater.

Open trickling filter: an innovative, cheap and simple form of post-treatment of sanitary effluents from anaerobic reactors in small communities

2012 ◽  
Vol 2 (2) ◽  
pp. 59-67 ◽  
Author(s):  
P. C. Vieira ◽  
M. von Sperling
Keyword(s):  
Loading Rate ◽  
Oxygen Demand ◽  
Post Treatment ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Trickling Filter ◽  
Small Communities ◽  
Capital Costs

We aimed to evaluate the performance and cost savings of an innovative design of a trickling filter (TF) for small population sizes, developed at the Federal University of Minas Gerais, Brazil referred to as an open trickling filter (OTF). The OTF had no side walls and no perforated bottom slab, and was applied for the post-treatment of sanitary sewage from an upflow anaerobic sludge blanket (UASB) reactor. The OTF had crushed-stone packing (3.5 m high) and was operated with an average surface hydraulic loading rate of 4.1 m3 m−2 d−1 and an average volumetric organic loading rate of 0.10 kg BOD m−3 d−1 (biochemical oxygen demand). The average concentrations obtained at the OTF effluent were 48 mg TSS L−1 (total suspended solids), 132 mg COD L−1 (chemical oxygen demand), 51 mg BOD L−1, 19 mg TKN L−1 (total Kjeldahl nitrogen), 16 mg NH4+-N L−1 and 10 mg NO3−-N L−1, complying with local discharge standards. Analysis of the construction costs indicated savings of 74% compared to conventional TF. Based on the performance, compactness, simplicity and reduced capital costs, it is believed that the proposed OTF is a good alternative for small communities, especially in developing countries.

Using A Novel Continuous Bioreactor In Enhancing The Biogas Production

2021 ◽  
Author(s):  
Mohammad Amui Khorshidi ◽  
Hossein Beiki ◽  
Mojtaba Kanvisi
Keyword(s):  
Production Process ◽  
Fossil Fuels ◽  
Biogas Production ◽  
Continuous Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Constant Composition ◽  
Continuous Bioreactor ◽  
Cumulative Volume ◽  
Volumetric Rate

Abstract Background: Since fossil fuels are limited and their burning is considered the main reason for environmental pollution, thinkers in the energy section are looking for a substitute for them. They have considered biogas as a potent replacement. Constant composition and volumetric rate, are ones of the challenges faced in term of using biogas. Therefore, in this study, a novel easily portable continuous bioreactor was designed and constructed to produce biogas at constant composition and volumetric rate, which is suitable for human uses. Sugar beet waste and anaerobic sludge were used as substrate and inoculum with an S/I ratio of 0.5 to 1, to produce biogas. Four parameters, i.e., hydraulic retention time (HRT), pH, biogas volume, and methane composition, were measured and compared.Results: The results of the mentioned reactor were compared with those of batch ones. The measurement revealed that the continuous reactor had a good performance on biogas purity and volumetric rate. The biogas contained about 53% methane. The suitable and preferable HRT and organic loading rate (OLR) were 18 days and 34.86 g VS/day. After the 18th day of operation, the biogas production process inside the continuous reactor was stable reaching about 411.2 ml STD/g VS per day.Conclusions: The reactor designed makes the biogas production process more manageable. Besides the production of the cumulative volume of biogas and constant methane percentage was achieved. As a result, the biogas produced is consumed daily, and a certain amount of gas is available every day. Since the percentage of gas produced is constant, it is possible to adjust the gas appliances with this amount of methane.

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