• KSBB Journal
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• v.6 no.2
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• pp.135-141
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• 1991

This study thus looks into two treatment processess : i) Anaerobic digester coupled with hollow fibre membrane unit. Treatment of starch waste with anaerobic digester-membrane system was studied. $0.17\m^2$ area of hollow fibre membrane unit of known pore size was immersed into laboratory-scale anaerobic digestion system. The pore size of membrane was varied from 0.03 to $\0.15mu$m. The hydraulic retention time of anaerobic digester was varied from 1.5 to 10 days. The effect of hydraulic retention time on treatment efficiency was significant while effect of membrane size was not significant. The gas production was about 0.74㎥/kg COD treated. The COD removal efficient was about 80-95% depending on the hydraulic retention time. ii ) Crossflow ultrafiltration as post treatment to anaerobic filter. The effluent from anaerobic filter, which had a total COD in the range of 4,500-5,200 mg/L was treated by crossflow ultrafiltration units. The study conducted with different membrane pore size indicated that membrace with 1,000,000 molecular weight cut-off size gave a higher COD removal efficiency in the range of 83-87% while giving a study flux of $120-130 L/\m^2$.h. A study was conducted to see the long term clogging effect of membrane also.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.540-545
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• 2006

The anaerobic digester supernatant (ADS) with high $NH_4-N$ concentration often results in a $NH_4-N$ overloading to the mainstream process of municipal wastewater treatment plant (MWTP). The nitrogen removal from the ADS is therefore important in order to achieve a stable mainstream process performance as well as to prevent $NH_4-N$ overloading due to ADS. Recently because of several advantages compared to the full nitrification, many works have shown interests in controlling the build-up of $NO_2-N$ in nitritation processes. The application of nitritation could save the aeration power compared to the full nitrification processes. In addition, the denitrification of $NO_2-N$ could reduce organic carbon requirements compared to the $NO_3-N$ denitrification. The purpose of this research was to find out the characteristics of the ADS nitritation and $NO_2-N$ accumulating factors from the laboratory reactor study. As a result based on the long-term laboratory experiment, it can be concluded that the degree of nitritation was closely related with the availability of alkalinity, free ammonia (FA), solid retention time (SRT) and solid concentration in the nitritation reactor.

• Journal of Radiation Industry
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• v.4 no.1
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• pp.85-89
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• 2010

The radioactive experiments are carried out for diagnosis of a variety of industrial processes in terms of the operation condition and the efficiency by measuring the residence time distribution. However, it is not easy to interpret the residence time distribution using the conventional methods when the flow rate is not constant and a number of processes are coupled in a complicated manner. In these cases, they can be analyzed by describing the system with mathematical models that can be defined with the state-space equations. In this paper, the residence time distribution of sludge was measured with a radiotracer, $^{46}Sc-EDTA$, in the digester of which the flow rate varies with time. The digester was assumed as a linear time variant system since the flow rate changed during the experiment and the operation efficiency of the digester was calculated by applying the state-spae equations.

• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.563-571
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• 2011

The purpose of this study is to investigate the high strength ammonia oxidation of piggery wastewater. Laboratory scale reactors was operated using influent of piggery wastewater and effluent of anaerobic digester from piggery wastewater at $35^{\circ}C$ and $20^{\circ}C$. Results of various operating conditions were compared and analyzed. After analyzing the results, effluent of anaerobic digester from piggery wastewater required shorter Solid retention time (SRT) than influent of piggery wastewater. In terms of the temperature, stable ammonia removal and denitrification was achieved on the both of the condition. At the temperature of $35^{\circ}C$, nitrite conversion rate was better than $20^{\circ}C$. It can be concluded that treating the piggery wastewater using anaerobic digester on the condition of the temperature at $35^{\circ}C$ is more efficient on the nitritation of the piggery wastewater.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.104-111
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• 2011

In order to assess the performance of co-digester using pig slurry and food waste at the farm scale biogas production facility, the anaerobic facility that adopts the one-stage CSTR of 5 $m^3\;day^{-1}$ input scale was designed and installed under the conditions of the OLR of 2.33 kg $m^3\;day^{-1}$ and HRT of 30 days in an pig farmhouse. Several operation parameters were monitored for assessment of the process performance. The anaerobic facility was operated in three stages to compare the performance of the anaerobic co-digester. In the Stage I, that was fed with a mix of pig slurry to food waste ratio of 7:3 in the input volume, where input TS content was 4.7 (${\pm}0.8$) %, and OLR was 0.837-1.668 kg-VS $m^3\;day^{-1}$. An average biogas yield observed was 252 $Nm^3\;day^{-1}$ with methane content 67.9%. This facility was capable of producing an electricity of 626 kWh $day^{-1}$ and a heat recovery of 689 Mcal day-1. In Stage II, that was fed with a mixture of pig slurry and food waste at the ratio of 6:4 in the input volume, where input TS content was 6.9 (${\pm}1.9$) %, and OLR was 1.220-3.524 kg-VS $m^3\;day^{-1}$. The TS content of digestate was increased to 3.0 (${\pm}0.3$) %. In Stage III, that was fed with only pig slurry, input TS content was 3.6 (${\pm}2.0$) %, and OLR was 0.182-2.187 kg-VS $m^3\;day^{-1}$. In stage III, TS and volatile solid contents in the input pig slurry were highly variable, and input VFAs and alkalinity values that affect the performance of anaerobic digester were also more variable and sensitive to the variation of input organic loading during the digester operation. The biogas produced in the stage III, ranged from 11.3 to 170.0 $m^3\;day^{-1}$, which was lower than 222.5-330.2 $m^3\;day^{-1}$ produced in the stage II.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.4
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• pp.201-209
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• 2016

Theoretical maximum methane yield of glucose at STP (1 atm, $0^{\circ}C$) is 0.35 L $CH_4/g$ COD. However, most researched actual methane yields of anaerobic digester (AD) on lab scale is lower than theoretical ones. A wide range of them have been reported according to experiments methods and types of organic matters. Recent year, a MET (Microbial electrochemical technology) is a promising technology for producing sustainable bio energies from AD via rapid degradation of high concentration organic wastes, VFAs (Volatile Fatty Acids), toxic materials and non-degradable organic matters with electrochemical reactions. In this study, methane yields of food waste leachate and sewage waste sludge were evaluated by using BMP (Biochemical Methane Potential) and continuous AD tests. As the results, methane production volume from the anaerobic digester equipped with MET (AD + MET) was higher than conventional AD in the ratio of 2 to 3 times. The actual methane yields from all experiments were lower than those of theoretical value of glucose. The methane yield, however, from the AD + MET occurred similar to the theoretical one. Moreover, biogas compositions of AD and AD + MET were similar. Consequently, methane production from anaerobic digester with MET increased from the result of higher organic removal efficiency, while, further researches should be required for investigating methane production mechanisms in the anaerobic digester with MET.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.433-441
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• 2014

It has been known that sewage containing high-concentration nitrogen affects the efficiency of municipal wastewater treatment plants harmfully. Therefore, research has been actively conducted to treat sewage containing high-concentration nitrogen. The current study has analyzed organic compounds, conducted foaming tests, and operated a laboratory-level nitritation reactor with the subjects of anaerobic digester supernatant and livestock wastewater which are the typical kinds of sewage containing high-concentration nitrogen. According to the results of analyzing organic compounds, soluble inert components form the largest part of anaerobic digester supernatant while particle biodegradable components occupy the most part of livestock wastewater. About the retention time proper for the reaction of nitritation, anaerobic digester supernatant shows 2 days while livestock wastewater indicates 6 days. It seems that the difference in the proper retention time is resulted from the difference of properties in organic compounds and ammonium nitrogen concentration. In addition, livestock wastewater's reactor foam is generated comparatively more than anaerobic digester supernatant's, but it tends to be eliminated faster. It is expected that the findings of this study can be utilized as foundational data afterwards in applying the reaction of nitritation to municipal wastewater treatment plants.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.158.2-158
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• 1995

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.607-628
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• 1999

The swine waste industry is growing rapidly along with the world human population. The trend is toward more concentrated piggeries with numbers of herds in the thousands. Associated with these increased herds are large quantities of wastes, including organic matter, inorganic nutrients, and gaseous emissions. The trend in swine waste management is toward treatment of these wastes to minimize negative impact on the health and comfort of workers and animals and the atmosphere, water, and soil environments. Treatment of these wastes has traditionally involved land application, lagoons, oxidation ditches, and conventional batch and continuously stirred reactor designs. More sophisticated treatment systems are being implemented, involving advanced anaerobic digester designs, integrated with solids separation, aerobic polishing of digester effluents, and biological nutrient removal. This review discusses the present and future role of anaerobic processes in piggery waste treatment with emphasis on reactor design, operating and performance parameters, and effluent processing.

• Journal of Korean Society on Water Environment
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• v.29 no.3
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• pp.377-382
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• 2013

Enriching anammox bacteria (AMX) in a lab-scale granular sequencing batch reactor using local digester centrate, we observed the significant enrichment of the filamentous-like bacterial population. These bacteria were revealed as novel bacterial species (termed CHL) belonging to Chlorobi/Bacteroidetes phyla via Denaturing Gradient Gel Electrophoresis (DGGE). Further, niche differentiation of AMX and CHL quantification was observed in granule and filament biomass, suggesting AMX was dominant in the granule and CHL was dominant in the filament. Therefore, it was confirmed the structural role of CHL was indeed to aid the granule formation of the AMX. In parallel, the physiological role of CHL was suspected to degrade biopolymers in the digester centrate using nitrate as an electron acceptor.