• Journal of Animal Environmental Science
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• v.5 no.1
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• pp.37-44
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• 1999

This study was carried out to improve utilization of substitute fly-ash in bedding material of animal waste treatments. The amount used of fly-ash used in a pigpen or beef stall was 50% lower than that of existing bedding material of animal waste treatments. From the results, substitution effect of fly-ash put over the floor of the stable became much better. Effects of processed fly ash as a spread straw decreased ammonia(NH3) and Hydrogensulfide (H2S) gas at beef stall, but there was no benefit of replacement terms. Effect of processed fly ash as a spread straw increased 4∼5 times replacement terms more than control NH3 and H2S gas was decreased. A lot of maggots and porasites were grown at sawdust pig farm, but fly ash inhibited to grow maggots and paraeters. In conclusion, as substituting fly-ash for 5% sawdust(DM basis) in making animal waste into a compost with fly ash, we can reduce the sawdust purchasing costs and produce the high quality of a compost, especially a pollutant as NH3 and H2S gas, etc. from the process of biodegradation, and as substituting fly-ash(1,540 won per ton ; can be extended the replacement period of spreading straw approximatively 4∼5 times) for sawdusts(111,000 won per ton) will increase a real income in livestock house.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.5
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• pp.379-388
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• 2019

Chlorination and UV illumination are being widely applied to inactivate a number of pathogenic microbials in the environment. Here, we evaluated the inactivation efficiency of individual and combined treatments of chlorination and UV under various aqueous conditions. UV dosage was required higher in waste water than in phosphate buffer to achieve the similar disinfecting efficiency. Free chlorine generated by electrolysis of waste water was abundant enough to inactivate microbials. Based on these, hybrid system composed of sequential treatment of electrolysis-mediated chlorination and UV treatment was developed under waste water conditions. Compared to individual treatments, hybrid system inactivated bacteria (i.e., E. coli and S. typhimurium) and viruses (i.e., MS-2 bacteriophage, rotavirus, and norovirus) more efficiently. The hybrid system also mitigated the photo re-pair of UV-driven DNA damages of target bacteria. The combined results suggested the hybrid system would achieve high inactivation efficiency and safety on various pathogenic microbials in wastewater.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.6
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• pp.825-834
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• 2005

Two experiments were conducted with growing crossbred Super-Meat ducks at the experimental duck farm of Cantho University to evaluate the effects of reducing the proportion of soybean meal (SBM) in a broken rice (BR)-SBM mixture and providing soya waste (SW) ad libitum (Expt. 1), and reducing the proportion of fish meal (FM) in a BR-FM mixture and supplying ensiled shrimp waste (ESW) ad libitum (Expt.2). Both experiments included five treatments, with three replicates and ten growing ducks per replicate. In Expt.1, the five diets were based on BR and five levels of SBM, with SW offered ad libitum. The control diet (SBM25) consisted of 75% BR and 25% SBM, and the other four treatments included SBM levels of 20% (SBM20), 14% (SBM14), 8% (SBM8) and 0% (SBM0) mixed with BR to 100%, and with SW ad libitum. In Expt. 2, the control diet consisted of 86% BR and 14% FM, and the other dietary treatments had FM levels of 11% (FM11), 8% (FM8), 4% (FM4) and 0% (FM0) mixed with BR, and with ESW ad libitum. In Expt. 1, total intakes of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF) and metabolizable energy (ME) were higher for birds given SW (p<0.001). Total CP intake was highest on the SBM20 diet, and lowest on the SBM0 diet (p<0.001). Lower daily gain (DG) was found for the SBM0 diet (p<0.01). Carcass weights were higher on the control treatment, with the lowest values on the SBM0 diet (p<0.001). Gizzard weights were higher on diets with high intakes of SW (p<0.05). In Expt. 2, birds with high intakes of ESW (FM4 and FM0) had lower (p<0.01) daily intakes of DM. The total CP intakes declined (p<0.001) with higher intakes of ESW. The highest DG were for the control and FM11 diets, while the lowest value was for diet FM0 (p<0.001). The poorest feed conversion ratio (FCR) was for the FM0 treatment (p<0.01). Lower weights of carcass and breast muscle were found on the FM0 diet (p<0.001). Feed costs per kg gain were only slightly different between diets. However, the lowest feed cost was for ducks on the SBM0 and FM11 diets in Expt.1 and Expt. 2, respectively.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.362-372
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• 2010

Although different disposal routes of waste-activated sludge are possible, anaerobic digestion plays an important role for its abilities to further transform organic matter into methane. The potential of using methane as energy source has long been widely recognised and the present paper extensively reviews the principles of anaerobic digestion, the process parameters and hydrolysis. Hydrolysis is recognised as rate-limiting step in the complex digestion process. To accelerate the digestion and enhance the production of biogas, various pre-treatments can be used to improve the rate-limiting hydrolysis. These treatments include mechanical, thermal, chemical and biological interventions to the feedstock. All pre-treatments result in a lysis or disintegration of sludge cells, thus releasing and solubilizing intracellular material into the water phase and transforming refractory organic material into biodegradable species. The reader will finally be guided to extensive discussion for anaerobic digestion processes.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.452-461
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• 2017

This study was conducted to select an optimal approach to corn waste biochar (BC) application, and to evaluate the effects of combined application of BC and inorganic fertilizer (IF) on corn growth and soil chemical properties in a pot experiment. Corn growth differed with BC application timing and BC application levels. Based on the characteristics of corn growth in pot-based experiments, the selected optimal application conditions of BC were application of $500kg\;10a^{-1}$ at 20 days before sowing. Also, the chemical properties of the tested soil with BC after corn harvesting were significantly improved than those in the other treatments. In particular, soil pH and CEC regardless of application conditions were markedly increased by 0.04~0.19 units and $0.08{\sim}2.58coml_c\;kg^{-1}$ in BC treatments than without BC treatments. Additionally, combined application of BC and IF had greater effects on corn growth than single application of BC. Therefore, the results suggest using properly BC application conditions and a combination of BC and IF for effective corn cultivation in an upland field.

• Clean Technology
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• v.28 no.1
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• pp.32-37
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• 2022

Food waste is produced from food factories, food services, and home kitchens. The generated mass reached 5.4 million tons/year in 2020. The basic management technology for such waste has been biological degradation under an anaerobic environment. However, the whole process is intrinsically slow and considerably affected by the inner physicochemical properties of the waste and other surrounding conditions, which makes optimization of the process difficult. The most promising options to counter this massive generation of waste are eco-friendly treatments or recycling. As a preliminary step for these options, attempts were made to evaluate the feasibility and usability of three simulative models based on reaction kinetics. Model (A) predicted relative changes over reaction time for reactant, intermediate, and product. Overall, an increased reaction rate produced less intermediate and more product, thereby leading to a shorter total reaction time. Particle diminishing model (B) predicted reduction of the total waste mass. The smaller particles diminished faster along with the dominant effect of microbial reaction. In Model (C), long-chain cellulose was predicted to transform into reducing sugar. At a standard condition, 48% of cellulose molecules having 10⁵ repeating units turned into reducing sugar after 100 h. Also it was found that the optimal enzyme concentration where the highest amount of remnant sugar was harvested was 1 mg L^-1.

• Hwankyungkyoyuk
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• v.2 no.1
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• pp.92-99
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• 1991

According to our secondary school curriculum for natural science and technical circles, there be used 353 of chemical reagents including 24 kinds of harmful and toxicant components. At present, most school are discharging their school laboratory waste water without any chemical and physical treatments. So as to solve the environmental problem for water pollution, this study tried to research a kind of adsorbant utilizing saw dust, wasted wood sources and designed the simple processing system using the adsorbent. This adsorbent was made by extracting lignin substances from raw saw dust under the solution of 0.5N-NaOH at the temperature of $100^{\circ}C$. Their metal removed rates was measured not only by processing of column and vessel. but also by comparing the standard solution and real waste water. The results were proved as more than 90(%) of the adsorptive efficiency on the average from Pb, Cd, Cu except Cr(VI)in case of the school experimental waste water soaked in vessels a long with 4g of the adsorbent for 24 hours. The new processing system enables to remove most harmful and toxicant metals by filtering, sedimenting and adsorbing at the low cost.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.3
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• pp.35-43
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• 2017

This study was conducted to evaluate effects of Kimchi factory waste (KFW) as bulking agent on physicochemical properties of cow manure (CM) composting and of its application on lettuce growth. Treatments were designed as follows; CM compost [65 % CM + 35 % sawdust (SD); control], KFW 5 % (65 % CM + 30 % SD + 5 % KFW), KFW 10 % (65 % CM + 25 % SD + 10 % KFW) and KFW 15 % (65 % CM + 20 % SD + 15 % KFW). After composting for 25 days, temperature of KFW treatments was lower than that of control. As compared with control, water content of KFW 15 % treatment was low about $5^{\circ}C$, and content of organic matter (O.M.) and nitrogen (N) was higher. pH and O.M./N ratio of KFW treatments or control were unaffected. In comparison with germination index (G.I.), G.I.s of KFW treatments were more than 70 on 25 days and G.I. of control on 35 days. As applied with KFW composts in lettuce, dry weight of KFW 10 % and KFW 15 % were increased by 84 % and 67 %, respectively, than that of control. These results indicated that Kimchi factory waste was possible to use as the compost law materials in livestock manure composting and to replace some sawdust as bulking agent.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.255-260
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• 2002

This study was conducted to evaluate the effect of the proper application level of anaerobic digestion waste water on rice. The waste water was from methane fermentation of pig manure to use as a liquid manure. The mixture treatment of 70% liquid manure and 30% chemical fertilizer (LM 70%+CF 30%) and 100% liquid manure (LM 100%) treatment were higher number of tiller than other treatments at the both tillering and heading stages of rice. The yields of LM 70%+CF 30% and LM 100% treatments were a little higher than that of NPK treatment, but the mixture treatment of 50% liquid manure and 50% chemical fertilizer (LM 50%+CF 50%) was a little lower yield than NPK treatment. The periodic changes of the $NH_4-N$ and $NO_3-N$ contents of the NPK and the LM 50%+CF 50% treatments in paddy soil were a little higher than those of other treatments at the early stage of rice. The $NH_4-N$ contents of NPK and the LM 50%+CF 50% treatments in irrigation water quality were higher than those of other treatments, however there was no difference in $NO_3-N$ content among the treatments. The $NH_4-N$ and $NO_3-N$ contents of non fertilizer treatment in infiltration water quality were leached a little higher than those of other treatments. It may be due to poor growth of rice following to reduce the nutrient uptake by rice and to increase relatively the nutrient leaching to the ground water. The proper application level of anaerobic digestion waste water as a liquid manure could be suggested to apply LM 70%+CF 30%. All treatments were the same amount of nitrogen content for the standard application amount on rice.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.440-448
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• 2005

Physical and chemical properties of waste glass, such as bottle glass, plate glass, and LCD glass were investigated to test the feasibility of starting materials for the production of high quality foamed glass for insulating grade construction material without pre-treatments such as cleaning, and waste removals. For this purpose, chemical analysis, thermal analysis, crystalline analysis, and rheological analysis including viscosity were proceeded and the preparation of foamed glass under the qualitative conditions obtained from these various analysis was also attempted. Overall results of various analysis and investigations for these waste glass showed that waste bottle glass and plate glass have high possivility of use as feed materials for the production of foamed glass.