• Land and Housing Review
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• v.2 no.1
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• pp.87-92
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• 2011

The anaerobic digestion of food waste effluent through single- and two-phase process was estimated and compared in this study. The treatment efficiencies for total solid(TS), volatile solid(VS), tCOD(total COD) and sCOD(soluble COD) were invariably higher in the single-phase process, which was accounted for by the fact that the treatment efficiency of organic wastes usually showed an inverse relationship with organic loading rate in the anaerobic digestion. In fact, the organic loading rate was lower for single-phase process. The concentration of tCOD were significantly lower in two-phase process but much more biogas was produced, compared to single-phase anaerobic digestion process, which might be explained partly by the relatively higher stability of two-phase process resulting from the separation of acid phase from methane phase.

• Resources Recycling
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• v.26 no.1
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• pp.59-68
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• 2017

This study has been conducted to evaluate the effects of a single stage anaerobic co-biogasification of food waste and primary sewage sludge mixture (1 : 5 V/V%) according to mixing ratio (0% : CAP0, 0.5% : CAP0.5, 1%: CAP1.0) in red pepper powder, which was reported as the material anti-bacterial and anti-fungi, under mesophilic condition ($35^{\circ}C$). during 31 days. It showed that red pepper powder effected anaerobic bacteria, Especially, Hydrolytic bacteria and methanogenic bacteria was inhibited much more than Acetogenic bacteria with red pepper powder. at CAP0, Experimental cumulative methane yield (ECMY) and Experimental bio-energy production (EBEP) were 0.17 L $CH_4/g$ $VS_{fed}$ and 1,465 cal/g $VS_{fed}$ individually as the highest value during 31 days.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.3
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• pp.113-120
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• 2007

Anaerobic batch tests were performed to evaluate the characteristics of methane production from piggery manure such as the ultimate methane yield (UMY), the kinetic constant and the maximum methane production rate. The kinetic behavior of anaerobic degradation of piggery manure was assumed as a first order reaction. The UMY, the first order kinetic constant and the maximum methane production rate were 0.27~0.44L $CH_4/gVS$, $0.161{\sim}0.280d^{-1}$ and 0.043~0.120L $CH_4/d$, respectively. Reactor of piggery manure as the self-seed source of anaerobic digestion resulted in longer acclimation time than reactors seeded with anaerobic digested sludge (ADS). But there was no little difference in the UMY between the two seed materials. The anaerobic digestion can be effective for the treatment of piggery manure containing high concentration of solids, the two-stage anaerobic digestion is, however, thought to be more effective than the traditional single one.

• Korean Journal of Environmental Agriculture
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• v.30 no.1
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• pp.31-36
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• 2011

BACKGROUND: Disposal of slurry animal manure produced by an anaerobic slurry-type barn method is not easy since the animal slurry contain high moisture content which makes solid-liquid separation a difficult process. However, recently, the interest about anaerobic digestion process as an environment-friendly waste disposal method has gained a wide interest because it can treat highly organic matter contained by the piggery slurry, decrease the odor after treatment, and enable the effective recovery of the methane gas which is a valuable energy resource. The objectives of this study were to identify the solubilization characteristics and to improve the anaerobic digestion efficiency of piggery slurry through full-scale anaerobic digestion experiments. METHODS AND RESULTS: In a full-scale continuous anaerobic digestion operation, the adaptability of single anaerobic digestion and its digestion efficiency were also evaluated in the farm field. The actual pH range and alkalinity concentration of piggery slurry used during the operation were comparatively higher than the concentrations of pH and alkalinity in the digestion tank which were stable at 7.5~8.0, 4,008 mg/L (as$CaCO_3$), respectively. The removal efficiency of organic matter (TCOD) by anaerobic digestion was 75~90% and methane gas production amount was at 0.33 L/L/day, a little higher than that of ordinary animal manure. CONCLUSION(s): Our findings showed higher recovery of highly purified methane and greater efficiency of anaerobic tank digestion since its methane gas content was at 65~70%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.588-597
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• 2016

In this study, we attempted to improve the biogas production efficiency by varying the mixing ratio of the mixed sludge of organic wastes in the improved single-phase anaerobic digestion process. The types of organic waste used in this study were raw sewage sludge, food wastewater leachate and livestock excretions. The biomethane potential was determined through the BMP test. The results showed that the biomethane potential of the livestock excretions was the highest at $1.55m^3CN4/kgVS$, and that the highest value of the composite sample, containing primary sludge, food waste leachate and livestock excretions at proportions of 50%, 30% and 20% respectively) was $0.43m^3CN4/kgVS$. On the other hand, the optimal mixture ratio of composite sludge in the demonstration plant was 68.5 (raw sludge) : 18.0 (food waste leachate) : 13.5 (livestock excretions), which was a somewhat different result from that obtained in the BMP test. This difference was attributed to the changes in the composite sludge properties and digester operating conditions, such as the retention time. The amount of biogas produced in the single-phase anaerobic digestion process was $2,514m^3/d$ with a methane content of 62.8%. Considering the value of $2,319m^3/d$ of biogas produced as its design capacity, it was considered that this process demonstrated the maximum capacity. Also, through this study, it was shown that, in the case of the anaerobic digestion process, the two-phase digestion process is better in terms of its stable tank operation and high efficiency, whereas the existing single-phase digestion process allows for the improvement of the digestion efficiency and performance.

• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.532-536
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• 2016

In this study, single-stage continuous anaerobic reactors to treat sewage sludge were operated under different temperature (55 and $35^{\circ}C$; $R_{TAD}$ and $R_{MAD}$) to evaluate the reactor stability and performance of the thermophilic and mesophilic anaerobic digestion. During the overall digestion, both anaerobic reactors maintained quite stable and constant pH and total alkalinity (TA) values in the range of 6.5-8.0 and 3-4 g $CaCO_3/L$, respectively. After the start-up period, $R_{TAD}$ showed 10% higher VS removal efficiency than that of $R_{MAD}$ ($R_{TAD}$; 43.3%; $R_{MAD}$ : 33.6%). Although organic acids such as acetic and propionic acid were detected in both anaerobic reactors at the start-up period, all organic acids in $R_{TAD}$ and $R_{MAD}$ were consumed at the steady state condition. Also $R_{TAD}$ showed 31.4 % higher methane production rate (MPR) than that of $R_{MAD}$ at the steady state condition ($R_{TAD}$; 243 mL $CH_4/L/d$; $R_{MAD}$ : 185 mL $CH_4/L/d$). Meanwhile, the experimental results indicated similar methane yield between $R_{TAD}$ and $R_{MAD}$.

• Journal of Korean Society of Water and Wastewater
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• v.7 no.1
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• pp.5-12
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• 1993

The objectives of this paper are to present data to illustrate how an advanced digestion process, two-phase digestion, can provide superior performance in terms of waste stabilization efficiency and net energy recovery. As the result, it is possible to separate enrichment cultures of acidogenic and methanogenic organisms in isolated environments by kinetic control involving manipulation of dilution rates. In single-phase digestion process, HRT and COD loading for effective operation were 14.29 days and 2.33kg $COD/m^3$ day, but two-phase digestion may be conducted efficiently at 7 days of HRT and 5.71kg $COD/m^3$ day of loading. Data from this studies showed that the two-phase process is better than single-phase digestion under all test conditions when compared on the bases of gas yield and production rate, reductions of COD and VS, buffer capacity, and unconverted volatile acids in the effluent.

• Journal of Environmental Science International
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• v.9 no.1
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• pp.75-80
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• 2000

Kinetic data for the acid phase anaerobic digestion were presented in this study and the constants were determined with acid production rate and gas production rate. Process models based on continuous culture theory were used to describe the characteristics of the acid forming microorganisms and to enable further development toward utilization of the process in a more rational manner. Acid phase digestion can be separated with appropriate manipulation of hydraulic retention time in anaerobic digestion. Kinetic analysis of data from the various hydraulic retention times using a phase specific model obtained form the acid phase indicated maximum specific growth rate of 0.40/h, saturation constant of 2,000mgCOD.$\ell$, yield coefficient of 0.35 mgVSS/msCOD utilized and decay constant of 0.04/h for the acid production rate. Similar analysis of data for the gas production rate indicated maximum specific growth rate of 0.003/h, saturation constant of 2,200mgCOD/$\ell$, yield coefficient of 0.035 mgVSS/mgCOD utilized and decay constant of 0.06/h.