Optimizing the conversion of cow dung to bio-energy under anaerobic condition by varying the organic loading rate (OLR) using proto-types of Chinese fixed dome bioreactor (CFDB)

The rate at which feedstock is added to the anaerobic digester (AD) reactor has to be adjusted for the growth rate of methanogens bacteria. Increase in biogas yield is as a result of improved mathanogens forming bacteria. Under loading and over loading of feedstock in the AD reactor has effect on methanogens forming bacteria. If more feedstock is added than the bacteria are able to degrade, the process will become acidic. Feedstock has to been fed to the reactor at a uniform rate and volume. If feeding pattern has to change, this must be done gradually so that bacteria can adapt to the new conditions. For optimum biogas yield, required amount of feedstock must be added to the AD reactor. The aim of this research work is to determine the effect of organic loading rate (OLR) on biogas yield from food waste, water hyacinth, cow dung, waste water from abattoir, poultry dropping and pig dung. The experimental set up comprises of single stage and three-stage continuous AD reactors. The same quantity and composition of feedstock were used and this was subjected to a variation of OLR 0.5 kg/m3(1.5 kg/m3, 2 kg/m3, 2.5 kg/m3, and 3 kg/m3). The experiment was conducted within a mesophilic temperature range of 36°C-37°C, percentage total solid (%TS) of 9.98% and percentage volatile solid (%VS) of 78%. pH meter was used to monitored the daily pH reading of the slurry. It was observed that the quantity of biogas yield from the feedstock increases with increasing organic load rate to the optimum value of 1.5 kg/m3and started decreasing above the optimum value for a single stage AD reactor but this was not the case for the three-stages continuous AD reactors that experienced continuous increase in biogas yield with a successive increase in OLR from 1-5 kg/m3-3.0 kg/m3.

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Effect of Organic Loading Rate (OLR) of Slurry on Biogas Production Quality

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1115.325 ◽

2015 ◽

Vol 1115 ◽

pp. 325-330

Author(s):

Maizirwan Mel ◽

Nadiah Mohd Suhuli ◽

Avicenna ◽

Sany Izan Ihsan ◽

Ahmad Faris Ismail ◽

...

Keyword(s):

Loading Rate ◽

Biogas Production ◽

Oxygen Demand ◽

Continuous System ◽

Total Solid ◽

Organic Loading Rate ◽

Cow Dung ◽

Feeding Rates ◽

Organic Loading ◽

Biogas Yield

In this study, three different concentration of organic loading rate (OLR) were investigated to examine the effect of the change in the organic loading rate on the efficiency of the biogas production. Daily amount of biogas of different type of organic loading rate (OLR), rates of production of biogas, removal efficiencies of chemical oxygen demand (COD), total solid (TS) matter, volatile solids (VS) matter from the slurry were investigated in 30 days retention tyme using 50 L digester. The digester was operated at different organic feeding rates of 25000 mg/L COD, 50000 mg/L COD, and 75000 mg/L COD. The material used in this system is the fruits waste, vegetables waste and cow dung. The system operated in continuous system. The reactor showed stable performance with the highest quality of methane (concentration about70.3% of CH4) and rate of biogas production is 38.1 L/day with COD reduction of 52.1% during organic loading rate 50000 mg/L COD. As the organic loading rate was increased, the COD degradation and biogas yield decreased. Based on this result, the OLR of 50000 mg/L COD is suggested as design criteria for pilot biogas production.

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Effect of the addition of fatty by-products from the refining of vegetable oil on methane production in co-digestion

Water Science & Technology ◽

10.2166/wst.2012.458 ◽

2012 ◽

Vol 66 (10) ◽

pp. 2237-2242 ◽

Cited By ~ 4

Author(s):

M. Torrijos ◽

P. Sousbie ◽

L. Badey ◽

F. Bosque ◽

J. P. Steyer

Keyword(s):

Vegetable Oil ◽

Methane Production ◽

Loading Rate ◽

Organic Loading Rate ◽

Cow Dung ◽

Vegetable Waste ◽

Organic Loading ◽

Fruit And Vegetable ◽

Volatile Solids ◽

By Products

The purpose of this work was to investigate the effects of the addition of by-products from the refining of vegetable oil on the behavior of co-digestion reactors treating a mixture of grass, cow dung and fruit and vegetable waste. Three by-products were used: one soapstock, one used winterization earth and one skimming of aeroflotation of the effluents. Three 15 l reactors were run in parallel and fed five times a week. In a first phase of 4 weeks, the three reactors were fed with the co-digestion substrates alone (grass, cow dung and fruit and vegetable waste) at an organic loading rate (OLR) of 1.5 g VS/kg d (VS: volatile solids). Then, a different by-product from the refining of oil was added to the feed of each reactor at an OLR of 0.5 g VS/kg d, generating a 33% increase in the OLR. The results show that the addition of by-products from the refining of oil is an efficient way of increasing the methane production of co-digestion reactors thanks to high methane yield of such by-products (0.69–0.77 l CH4/g VS loaded). In fact, in this work, it was possible to raise the methane production of the reactors by about 60% through a 33% increase in the OLR thanks to the addition of the by-products from the refining of vegetable oil.

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Optimum Organic Loading Rate in the Biomethanation of a Mixture of Cow Dungs and Poultry Droppings

International Journal of Advanced Research ◽

10.37284/ijar.2.2.176 ◽

2020 ◽

Vol 2 (2) ◽

pp. 1-5

Author(s):

Julius Olatunji Jeje ◽

Oluwaseun Ruth Alo ◽

Tomiwa Oke Akadiri

Keyword(s):

Carbon Dioxide ◽

Loading Rate ◽

Organic Loading Rate ◽

Cow Dung ◽

Organic Loading ◽

Maximum Volume ◽

Loading Rates ◽

Poultry Droppings ◽

Sludge Concentration

The effect of varying the organic loading rate in the digester volume using a mixture of poultry droppings and cow dung as biomass was studied. The study was aimed at determining the optimum organic loading rates, which would produce the maximum volume of biogas from a mixture of poultry droppings and cow dung. The pH was maintained between 6.8 and 7.2. All other parameters affecting the production of gas were kept constant except the organic loading rate. The wastes, poultry droppings and cow dung was mixed in the ratio 60:40 and maintained at a sludge concentration of 700g/l. It was observed that biogas produced from the digester with the organic loading rate of 2.8 kg vs/m3/day gives the highest proportion of methane and the digester with organic loading rate of 3.2 kg vs/m3/day produced the highest proportion of carbon dioxide.

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Anaerobic Treatment of Polyethylene Terephthalate (PET) Wastewater from Lab to Full Scale

Water Science & Technology ◽

10.2166/wst.1999.0426 ◽

1999 ◽

Vol 40 (8) ◽

pp. 229-236 ◽

Cited By ~ 4

Author(s):

F. Fdz-Polanco ◽

M. D. Hidalgo ◽

M. Fdz-Polanco ◽

P. A. García Encina

Keyword(s):

Polyethylene Terephthalate ◽

Loading Rate ◽

Treatment Plant ◽

Textile Wastewater ◽

Anaerobic Treatment ◽

Cod Removal ◽

Organic Loading Rate ◽

Foam Formation ◽

Organic Loading ◽

Start Up

In the last decade Polyethylene Terephthalate (PET) production is growing. The wastewater of the “Catalana de Polimers” factory in Barcelona (Spain) has two main streams of similar flow rate, esterification (COD=30,000 mg/l) and textile (COD=4000 mg/l). In order to assess the anaerobic treatment viability, discontinuous and continuous experiments were carried out. Discontinuous biodegradability tests indicated that anaerobic biodegradability was 90 and 75% for esterification and textile wastewater. The textile stream revealed some tendency to foam formation and inhibitory effects. Nutrients, micronutrients and alkali limitations and dosage were determined. A continuous lab-scale UASB reactor was able to treat a mixture of 50% (v) esterification/textile wastewater with stable behaviour at organic loading rate larger than 12 g COD/l.d (0.3 g COD/g VSS.d) with COD removal efficiency greater than 90%. The start-up period was very short and the recuperation after overloading accidents was quite fast, in spite of the wash-out of solids. From the laboratory information an industrial treatment plant was designed and built, during the start-up period COD removal efficiencies larger than 90% and organic loading rate of 0.6 kg COD/kg VSS.d (5 kg COD/m3.d) have been reached.

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Performance of an anaerobic baffled reactor (ABR) as a hydrolysis-acidogenesis unit in treating landfill leachate mixed with municipal sewage

Water Science & Technology ◽

10.2166/wst.2000.0253 ◽

2000 ◽

Vol 42 (12) ◽

pp. 115-121 ◽

Cited By ~ 13

Author(s):

B. Wang ◽

Y. Shen

Keyword(s):

Landfill Leachate ◽

Loading Rate ◽

Granular Sludge ◽

Operational Performance ◽

Municipal Sewage ◽

Organic Loading Rate ◽

Stable Operation ◽

Organic Loading ◽

Anaerobic Baffled Reactor ◽

Biological Treatability

A study on the performance of an Anaerobic Baffled Reactor(ABR) as a hydrolysis-acidogenesis unit in treating the mixed wastewater of landfill leachate and municipal sewage in different volumetric ratios was carried out. The results showed that ABR substantially improved the biological treatability of the mixed wastewater by increasing its BOD5/COD ratio to 0.4–0.6 from the initial values of 0.15–0.3. The formation of bar-shaped granular sludge of 0.5–5 mm both in diameter and length with an SVI of 7.5–14.2 ml/g was observed in all compartments of the ABR when the organic loading rate reached 4.71 kgCOD/m3 · d. The effects of the ratios of NH4+-N/COD and COD/TP in mixed wastewater on the operational performance were also studied, from which it was found that a reasonable NH4+-N/COD ratio should be lower than 0.02, and the phosphorus supplement was needed when the volumetric ratio was higher than 4:6 for stable operation of ABR.

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