• Environmental Engineering Research
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• v.19 no.3
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• pp.185-195
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• 2014

Despite the enormous technical and economic efforts to improve environmental conditions, currently about 40% of the global population (or 2 billion people) are still lack access to safe water supply and adequate sanitation facilities. Pollution problems and transmission of water- related diseases will continue to proliferate. The rapid population growth and industrialization will lead to a reduction of arable land, thus exacerbating the food shortage problems and threatening environmental sustainability. Natural systems in this context are a transdisciplinary approach which employs the activities of microbes, soil and/or plants in waste stabilisation and resource recovery without the aid of mechanical or energy-intensive equipments. Examples of these natural systems are: waste stabilisation ponds, aquatic weed ponds, constructed wetlands and land treatment processes. Although they require relatively large land areas, the natural systems could achieve a high degree of waste stabilisation and at the same time, yield potentials for waste recycling through the production of algal protein, fish, crops, and plant biomass. Because of the complex interactions occurring in the natural systems, the existing design procedures are based mainly on empirical or field experience approaches. An integrated kinetic model encompassing the activities of both suspended and biofilm bacteria and some important engineering parameters has been developed which could predict the organic matter degradation in the natural systems satisfactorily.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.2
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• pp.86-96
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• 2003

This study was conducted to investigate use possibility of pharmaceutical byproducts(process sludge) and waste water sludges as raw materials of organic compost at Fertilizer Official Regulation of Fertilizer Management Law in 2002. All pharmaceutical byproducts were satisfied the standard levels of raw material regulated in organic compost, some waste water sludges were deficient in the level. The content of n-hexane extractable material(HEM) was in byproduct higher than in waste water sludge. This was presumed that the sludge with containing a lot of organic matter was high in HEM content. Of the whole microorganism flora, bacteria was mainly detected, and yeast and filamentous fungi took up less population which was fluctuated depending on the source of sludges. Most dominated bacteria were identified into Genus of Pseudomonas. Pseudomonas syringae and Rathayibacter bathayi was classified as plant pathogenic bacteria.

• Journal of Environmental Science International
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• v.10 no.4
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• pp.275-280
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• 2001

In an attempt to evaluate the possibility of producing an organic fertilizer using sediments from coastal farming areas, the chemical composition, bacteriological quality and heavy metals in the sediments alkalized by conditions : a 1:4 mixture of dry sediment to food wastes and the addition of 30% quicklime to the mixture. According to the classification standard for compost constituent by Higgins, all composts had a low or intermediate grade in T-N and $K_2O$ content, a low grade in $P_2O_5$ and a high grade in CaO and MgO content. Stabilization by quicklime and magnesium hydroxide is likely to inhibit th bacterial decomposition of organic matter and the actigity of pathogenic organic. Raising the pH of stabilized sediment to 12 for 2 hours(PSRP criteria of EPA) allowed 99.99% of the coliform group, fecal group and viable cell count to be reduced. the results suggested that the crude fertilizer produced by alkaline stabilization method was innoxious and thereby the sediments from coastal farming areas could be used as organic fertilizer.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.259-265
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• 2008

Generally speaking, there are two widely used methods of Nitrogen removal from waste water: 1) nitrification using autotrophic microorganisms, and 2) denitrification using heterotrophic microorganisms. The C/N ratio is an important factor of the denitrification process. In this case, if methanol is added to increase the lacking organic matter, a high economic cost is incurred and methanol is left in the processed water. In an effort to fix these issues, autotrophic denitrification through the use of Hydrogen, Iron and Sulfur is being studied, and among those Sulfur is cheaper and carries out denitrification effectively, and therefore is being studied the most. In this study, after cultivating T. denitrificans, the presence of T. denitrificans was determined and the effectiveness of denitirification via T. denitrificans was studied. In order to find out about the inhibition of T. denitrificans from the loading of organic matter, this shows that the greater the loading of organic matter, the more the denitrification ability of T. denitrificans is hindered. In order to research the hindrance of T. denitrificans resulting from the loading of $NO_3{^-}-N$, these results show that concentrations less than 100mg/L per 100mL of gel volume do not hinder T. denitrificans. In order to research the optimization of denitrification resulting from T. denitrificans, three 500mL samples of Sulfur granules were prepared: 1) one with only T. denitrificans attached (Mode I), 2) one with both T. denitrificans and active sludge attached (Mode II), and 3) one with only active sludge attached (Mode III). The results showed that autotrophic denitrification using S from Mode I was the most active.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.147-151
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• 1987

This study was conducted to evaluate the effect of the liquid waste from methane fermentation on chemical components, digestible dry matter and net energy of pasture mixtures of orchard grass, tall fescue, Kentucky bluegrass and ladino clover. The total crude proteins and crude ashes increased with the application of liquid waste, but N-free extracts decreased somewhat and it didn't affect the content of crude fat and crude fiber. Amounts of neutral detergent fiber and acid detergent fiber increased with increasing application of liquid waste and the content of cellulose in cell-wall constituents decreased, but hemicellulose increased. The digestible dry matter was produced 405 kg/10a at optimum application of 42 MT/10a liquid waste compared to NPK check plot of 233 kg/10a. The starch value and net energy lactation were 291.3 KStE and 3450 MJ-NEL respectively indicating that the optimum application of liquid waste increased their values.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.2
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• pp.28-35
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• 2015

In this study, the experiment was carried out to produce methane by applying Semi-Continuous Leachate Recirculation Anaerobic Digestion System fed with source separated food waste from school cafeteria. There were two systems and each system consisted of a bioreactor and a liquid tank. Each bioreactor had a screen near the bottom of the reactor. 2.5L of separated liquid was transferred to the liquid tank for 30min each day by using a tubing pump and the liquid from the liquid tank was pumped to the bioreactor at the upper of the bioreactor as soon as the transfer was ended. Through this circulation, the liquid having high concentration of VFAs was supplied to the top of bioreactor. At the beginning of the experiment, food waste/inoculum anaerobic sludge volume ratio was 2:8 that is 9g VS/L of OLR(Organic Loading Rate). Feeding was conducted every two weeks. Experimental results showed that the contents of moisture, combustible matter, ash were 65.91%, 32.73%, and 1.36%, respectively. Two different food waste loading were studied. The average organic loading rates were 3.51g VS/d for System A and 3.86g VS/d for System B, respectively. The average produced methane based on food waste fed to bioreactor were observed as $6.30m^3CH_4/kgVS{\cdot}d$ for system A and $4.94m^3CH_4/kgVS{\cdot}d$ for System B, respectively.

• Korean Journal of Agricultural Science
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• v.42 no.3
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• pp.177-181
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• 2015

Food waste has been widely considered as a recycling resource to be applied to agricultural lands due to the effects of organic matter and nutrient for plant productivity. but the maturity and salt concentration in the compost produced from food waste processing facilities should be considered firstly, which was little information on compost quality produced from food waste treatment facility. In this study, we examined actual situation of food waste processing facility on the composting of food waste and evaluated the characteristics of composts produced from food waste processing facilities. The quality of composts was analyzed on the basis of the criteria of fertilizer processing manual. The 46% of food waste treatment facility registered composting produced actually the compost mixed with food waste or animal waste. The compost maturity and salt concentration as indicators of the quality of compost were not met 46.8% of composts collected from food waste processing facilities to the criteria of fertilizer processing manual. Also, 15.6%(moisture) were not satisfied with the criteria. In conclusion, the compost produced from food waste processing facilities is firstly required with better compost maturity and reduced salt concentration in order to use to agricultural lands as an amendment.

• The Korean Journal of Ecology
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• v.21 no.3
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• pp.313-320
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• 1998

Ameliorating effects of dolomite and sludge on the polluted soil sampled from Ulsan and yeocheon Industrial Complexes were investigated. Ameliorating effects were analysed by changes of soil properties and plant growth after treatment of dolomite and sludge. Soil properties were investigated by analysing organic matter, N, P, K, Ca and Mg contents and pH. Growth of sample plants was investigated by leaf area calculated from length and breadth of leaves and by biomass from diameter and height of sample plants. Quercus serrata and Celtis sinensis selected as tolerant plants in field survey were used as experimental plants. Treatment with dolomite showed ameliorating effects by increassing n, Ca, and Mg com\ntents, and pH of soil and by decreasing Al content. Treatment of sludge showed similar effects by increasing N, Ca, Mg and organic matter contents, and by decreasing A1 content. But treatment of sludge did not show any effect on pH. Both soil ameliorators showed accelerating effects on the growth of experimental plants in Ulsan soil. But those effects in Yeocheon soil were somewhat different. Treatment of sludge showed accelerating effects of the growth of both sample plants but dolomitic liming did not so. From those results, we confirmed availability of sludge, a kind of industrial waste, as one of ameliorators of the polluted soil. In addition, we recognized that soil properties had to be considered to select soil ameliorators suitable for restoration of degraded ecosystems.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4204-4212
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• 2023

Background: Storage reservoirs of radioactive waste could be the source of atmospheric pollution due to the efflux of aqueous aerosol from their water areas. The main mechanism of formation of aqueous aerosols is the collapse of gas bubbles at the water surface. In this paper, we discuss the potential influence of biological factors on gas ebullition in the water areas of the radioactively contaminated industrial reservoirs R-9 (Lake Karachay) and R-4 (Metlinsky pond) of the Mayak PA. The emission of the released non-dissolved gases captured with gas traps in reservoir R-9 was (88-290) ml/m² per day (2015) and in reservoir R-4 (270-460) ml/m² per day (2016). The analysis of gas composition in reservoir R-4 (60% methane, 35% nitrogen, 2.4% oxygen, 1.5% carbon dioxide) confirms their biological origin. It is associated with the processes of organic matter destruction in bottom sediments. The major source of organic matter in bottom sediments is the dying phytoplankton developing in these reservoirs. Conclusion: The obtained results form the basis to set a task to quantify the relationship between the phytoplankton development, gases ebullition and radioactive atmosphere contamination.

• Journal of Animal Environmental Science
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• v.4 no.2
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• pp.167-174
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• 1998

It is known that the anaerobic fermentation of organic matter (OM) is divided into 2 phases, acidogenic phase in which OM is digested into volatile fatty acid (VFA), and methanogenic phase where the produced VFA is converted to CH4 and CO2. In a natural fermenting procedure, these 2 phases occur at the same time. However the total production of end products (methane) may be limited if these 2 phases occur at the same time. This is believed to be due to the difference in growth rate, substrate-utilizing efficiency and favorable environment for each microbes (acidogens and methanogens), involved in each phase. It is therefore suggested for the maximum recycling of organic waste (such as animal waste) through providing 2 different steps in fermenting procedure, acidogenic phase and methanogenic phase, in each case the activity of involved microbes can be maintained at the maximum level. The results obtained from these experiments are summarized as follows : The loading rates of swine waste were made through 2.5, 5 and 10 gVS / l / d to identify its acidogenic fermenting character in this study. The VFA yield was maximized at 10 gVS / l / d of loading rate. On the basis of this study was executed to identify the optimum HRT of 1, 2 and 4 days at 10 gVS / l / d of loading rate in acidogenic phase. The maximum VFA yield was obtained at 1 days of HRT.