• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.173-181
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• 2010

This study was conducted to investigate the possible installation of small hydro-power plant at the discharge point of Gumi sewage treatment plant (STP) using treated wastewater. Sufficient amount of water to transfer to electric power and the selection of proper location are two essential elements for the construction of small hydro-power facility. Preliminary analysis based on site visit and existing data in Gumi STP were made. Capacity of the small hydro-power plants and exact location were determined by geomorphological condition and flow duration characteristics. Flow duration characteristics and its duration curve were identified using monthly rainfall data in Gumi STP. Relevant facts of small hydro-power system in other STP were referred to adopt to Gumi STP situation. Flowrate of treated effluents and effective head between flow chamber and the location of hydraulic turbine in Gumi STP are found to be $3.70m^3$/sec and 3.5m respectively. Electric generation rate based on this feasibility study was estimated to be 86.3kW/h. Yearly electric generation rate was expected to be 932.4MMh. Proposed small hydro-power plant construction in Gumi STP is to be reasonable.

• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.3
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• pp.69-76
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• 2005

An Absorbent Biofilter System (ABS) combined with the recirculation process was investigated for the feasible application in additional removing of organics (BOD, SS) as well as nutrients (TN, TP) from small Community wastewater in Korea. Polyurethane biofilter media with high porosity and large surface area were /used for the aerobic system. A part of treated wastewater was recirculated into the anoxic septic tank to promote removal of nutrients. The concentrations of BOD and SS of treated wastewater satisfied the regulations for small on-site wastewater treatment facility (10 mg/L) during the overall experimental period. The effluent concentrations of BOD and SS were decreased with enhancement of removal efficiencies of 95.7 and $96.7\%$. The nitrogen and phosphorus removal efficiencies by the recirculation increased to $52.9\%\;and\;43.2\%$ in average during the overall experimental period, respectively. With the improvement, these values were increased as much as additional 42 and $18\%$ compared with those of non-recirculation. The rates of nitrification and denitrification were enhanced showing $65\~77\%\;and\;42\~92\%$, respectively. The described process modification is a low cost and effective method of enhancing nitrogen and phosphorus removal, especially on existing systems without changing major design components of a treatment facility.

• Journal of Environmental Science International
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• v.2 no.2
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• pp.145-152
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• 1993

An experimental research was conducted in order to study the treatability of leachate and a combined wastewater of municipal landfill leachate and municipal sewage. The landfill leachate was that of Nanjido landfill site, and the municipal sewage was obtained from Chungnang municipal sewage treatment plant of Seoul. Several sets of bench-scale sequencing batch reactor(SBR) were used as experimental apparatus. Specially investigated items in this experiment were the removal efficiency of substrate and the influence of the hydraulic retention time(HRT). The experiment lasted for about 8 months. The result are as follows ; 1) The characteristics of leachate were pH 7.4~8.1, BOD 280~450 mg/l, COD 1300 ~ 1350 mg/l, T-N 2021 ~2110 mg/1,7-P 2.7 ~3.2 mg/l, Cl-3540 ~4085 mg/l, and heavy metals are a very small amount. And the characteristics of sewage Ivere pH 6.9~7.3, BOD 78.4~129.3 mg/1, COD 121.2~305.0 mg/l, T-N 14.9~36.4 mg/l, T-P 1.3 ~5.9 mg/l. 2) The treatability of leachate alone was not treat well. So for the good treatment of leachate, it was necessary to deal with the pretreatment before biological treatment and a combined treatment of municipal serfage. 3) The various contents of the leachate were 5%, 10%, and 50% and the removal efficiency of COD was 86.0%, 82.8%, 60.6%, and 31.7%. The maximum content of the leachate which could be sucessfully treated by SBR in the combined treatment was 10% of that of sewage.

• Journal of fish pathology
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• v.17 no.1
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• pp.57-66
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• 2004

Effects of oral administration with fermented product from sewage in land-based seawater fish farm on haematological disturbance in the olive flounder, Paralichthys olivaceus was investigated. After 4 weeks of conditioning with a basal diet, fish were divided into 4 groups and provided experimental diet (0.1, 0.5, 1.0 and 2.0%) supplement of fermented sewage for 80 days. Proximal analysis was performed for the product of sewage which was fermented by lactic acid and yeast. RBC count, hemoglobin concentration and hematocrit value were increased according to the treated periods, however, no statistical difference was observed between control and treatment groups. There were no significant difference in serum organic, inorganic compounds and enzyme activities between control and treatment groups. This study hypothesized that the supplement of fermented product from sewage in land-based seawater fish farm might be an additive supplement for source of fish diet in view of haematological examination. Recycling of the sewage may be an economic artificial sources of diet for fish aquaculture practices.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1232-1237
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• 2009

Recently, we often encounter water shortage problem due to drought during dry season. Although we have built dams and expanded our tap water system greatly to meet the increasing demand of water, this approach has its inherent limitation including environmental destruction in the course of the dam construction. Therefore, this paper is aimed to analyze the water recycling models developed in other countries and modify them to fit into our system. Also the water recycling system in Busan municipal area was analyzed to propose an alternative method for reusing the recycled water from wastewater treatment area.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.122-128
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• 2003

To develop a Mg-Zeolite for simultaneous recovery of the N and the P from sewage water, the natural zeolite was treated with 20% $MgCl_2$ solution by changing the pH the temperature and the treating time of the solution. And the contents of Ca Fe Na K Mg of Mg-Zeolite were analyzed by ICP. The optimum treatment condition for Mg-Zeolite was induced to pH 7.0 $50^{\circ}C$ in 20% $MgCl_2$ solution and for 80min treatment. And the Na and the K ions in natural zeolite are significant factors for Mg exchange in the zeolite.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.2
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• pp.13-24
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• 2023

Sewage sludge has been widely used as an organic fertilizer in agriculture. However, sewage sludge can cause serious malodor problems resulting from the decomposition of organic compounds in anaerobic conditions. The malodor of sewage sludge mainly occurs due to a low carbon to nitrogen ratio (C/N), high moisture, and low temperature, which are ideal conditions for ammonia emissions. Therefore, in this study, we investigated the reduction of the odor-causing ammonia nitrogen (NH₃-N) in sewage sludge by co-application of microbes and methanol (MeOH). The physico-chemical properties of the municipal sewage sludge showed that the odor was mainly caused by a higher NH₃-N content (2932.2 mg L^-1). Supplementation with MeOH (20%) as a carbon source in the sewage sludge significantly reduced the NH₃-N up to 34.2% by increasing C/N ratio. Furthermore, the sewage sludge was treated with the NH₃-N reducing and plant growth promoting (PGP) bacteria Stenotrophomonas rhizophila SRCM 116907. The treatment with S. rhizophila SRCM 116907 significantly increased the seedling vigor index of Lolium perenne (10.3%) and Chrysanthemum burbankii (42.4%). The findings demonstrate that supplementing sewage sludge with methanol significantly reduces ammonia emissions, thereby mitigating malodor problems. Overall, the study highlights the potential of using a microbial and methanol approach to improve the quality of sewage sludge as an organic fertilizer and promote sustainable agriculture.

• Journal of Energy Engineering
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• v.7 no.2
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• pp.231-240
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• 1998

The global environmental problems such as CFC, energy losses in heat recovery system as well as summer peak time power demands, the development of high efficiency absorption refrigeration systems is one of the most promising method in this problems. The absorption refrigeration system to utilize treated sewage is available for environmental protection and energy conservation. Simulation analysis on the double-effect absorption refrigeration cucles with parallel or series flow type has been performed. LiBr+LiI+LiCl+LiNO$_3$ solution was selected as the new working fluid. The main purpose of this study is evaluating the possibilities of effective utilization of treated sewage as a cooling water for the absorber and condenser. The other purpose of the present study is to determine the optimum designs and operating conditions based on the operating constraints and the coefficient of performance in the parallel or series flow type. In this study, we found out the characteristic of new working solution through the cycle simulation and compared LiBr solution to evaluate. The absorption refrigeration machine using the new working fluid was obtained better results COP rise and compactness of system by comparison with LiBr solution.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.116-122
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• 2008

Fungal floras were investigated for the lysimeter soil treated with municipal sewage sludge (MSS), pig manure compost (PMC), industrial sewage sludge (ISS), leather processing sludge (LS), and alcohol fermentation processing sludge (FS). Fungal populations were higher in the FS, ISS, LS, or MSS-treated soil than in the chemical fertilizer-treated soil. Isolated fungi from the sewage sludge were identified as Penicillium spp., Gliocladium spp., Acremonium spp., Trichoderma spp., Aspergillus spp., Blastomyces spp., and Phoma spp.

• Journal of the Korean Solar Energy Society
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• v.34 no.6
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• pp.19-25
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• 2014

Alternative sources of energy take a higher interest in order to reduce the greenhouse gas under the Climate Change Convention, fossil fuel consumption, and lower social anxiety about nuclear power such as crisis involving the Fukushima plant, problem of obsolete equipment. The energy consumption of agriculture, forestry and fisheries in South Korea is 3,082,000toe by 2011, reliance on electrical energy(35%) and oil(57.2%) is very high with 92.2%. In this study, we examined reserves and available capacity of temperature difference energy for thermal discharge from plant, treated sewage, river water, dam, and agricultural reservoir in rural community. Reserves of unutilized energy are 455,735Tcal/yr in rural community, these accounts for 78% of total reserves 582,385Tcal/y. Thermal discharge from plant has the most reserves of unutilized energy in rural community, it is estimated that it has the reserves of 277,410Tcal/y. Available capacity of unutilized energy in rural community is total 134,147Tcal/y, thermal discharge from plant available for heating is the most 128,035Tcal/y, and it shows in the order of treated sewage 4,318Tcal/y, river water 1,653Tcal/y, and reservoir 141Tcal/y. Elevating temperature area of green house by 2012 is 21,208ha. The amount of energy required for heating the greenhouse a year is dbout 11,365Tcal/y with 8.5% of the total available capacity of unutilized energy.