• Journal of Korean Society of Environmental Engineers
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• v.32 no.1
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• pp.53-60
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• 2010

In the present study, experiments have been performed to investigate the possibility of removing Cochlodinium polykrikoides using the dredged sediment from a coastal fishery and then to derive the optimal conditions; the amount and particle size of dredged sediment besprinkled into water, the thermal treatment, the types and amounts of additives, and the depth profile of Cochlodinium polykrikoides. Results showed that the optimal amount of dredged sediment besprinkled into water was 6~10 g/L, and the removal efficiency of Cochlodinium polykrikoides after the reaction time for 60 min was 73~93%. Note that, in the real sea water, it is necessary to besprinkle 6~10 $kg/m^3$ of dry dredged sediment on a unit area (1 $m^2$). With decreasing particle size, Cochlodinium polykrikoides could be more efficiently removed. The removal efficiency was 93% with the dredged sediment smaller than 100 ${\mu}m$, whereas it was 51% with that of 100 ${\mu}m$ ${\mu}m$. Since most of dredged sediment (over 90%) was smaller than 100 ${\mu}m$, high efficiency could be obtained by besprinkling only the dredged sediment without pre-treatment. CaO was found to be an effective additive in promoting the removal efficiency (up to 99%). The optimal amount of additive was 5~10%, however, it was necessary to use as small amount of an additive as possible in order to avoid the sharp increase in pH. The removal efficiency increased with increasing depth profile of Cochlodinium polykrikoides. The removal efficiency was 83% at 5 cm depth, whereas it was 93% at 50 cm depth. In the sea water, red tide occurred within 3 m depth, and furthermore most Cochlodinium polykrikoides existed within 1 m depth. It was, therefore, expected that higher removal efficiency of Cochlodinium polykrikoides could be obtained when the dredged sediment was besprinkled into the sea water. The removal efficiency of Cochlodinium polykrikoides was up to 93% when the dredged sediment (<100 ${\mu}m$) was besprinkled into water at the ratio of 10 g/L. This result was comparable to that obtained with loess (90~97%). All the results in the present study indicated that the dredged sediment from a coastal fishery could be successfully used as a substitute of loess for removing the red tide alga.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.4
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• pp.223-231
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• 2012

The purpose of this study is to investigate basically the mechanism of heat transfer by the resolution of complex fluid flow inside a sophisticated designed screw dryer for the treatment of sewage sludge by using numerical analysis and experimental study. By doing this, the result was quite helpful to obtain the design criteria for enhancing drying efficiency, thereby achieving the optimal design of a multiple screw type dryer for treating inorganic and organic sludge wastes. One notable design feature of the dryer was to bypass a certain of fraction of the hot combustion gases into the bottom of the screw cylinder, by the fluid flow induction, across the delicately designed holes on the screw surface to agitate internally the sticky sludges. This offers many benefits not only in the enhancement of thermal efficiency even for the high viscosity material but also greater flexibility in the application of system design and operation. However, one careful precaution was made in operation in that when distributing the hot flue gas over the lump of sludge for internal agitation not to make any pore blocking and to avoid too much pressure drop caused by inertial resistance across the lump of sludge. The optimal retention time for rotating the screw at 1 rpm in order to treat 200 kg/hr of sewage sludge was determined empirically about 100 minutes. The corresponding optimal heat source was found to be 150,000 kcal/hr. A series of numerical calculation is performed to resolve flow characteristics in order to assist in the system design as function of important system and operational variables. The numerical calculation is successfully evaluated against experimental temperature profile and flow field characteristics. In general, the calculation results are physically reasonable and consistent in parametric study. In further studies, more quantitative data analyses such as pressure drop across the type and loading of drying sludge will be made for the system evaluation in experiment and calculation.

• Economic and Environmental Geology
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• v.55 no.6
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• pp.727-736
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• 2022

Ice wedges are subsurface ice mass structures that formed mainly by freezing precipitation with airborne dust and surrounding soil particles flowed through the active layer into the cracks growing by repeating thermal contractions in the deeper permafrost layer over time. These ice masses characteristically contain high concentrations of solutes and solids. Because of their unique properties and distribution, the possibility of harnessing ice wedges as an alternative archive for reconstructing paleoclimate and paleoenvironment has been recently suggested despite limited studies. It is imperative to preserve the physicochemical properties of the ice wedge (e.g., solute concentration, mineral particles) without any potential alteration to use it as a proxy for reconstructing the paleo-information. Thawing the ice wedge samples is prerequisite for the assessment of their physicochemical properties, during which the paleo-information could be unintentionally altered by any methodological artifact. This study examined the effect of thawing conditions and procedures on the physicochemical properties of solutes and solid particles in ice wedge samples collected from Cyuie, East Siberia. Four different thawing conditions with varying temperatures (4 and 23℃) and oxygen exposures (oxic and anoxic) for the ice wedge sample treatment were examined. Ice wedge samples thawed at 4℃ under anoxic conditions, wherein biological activity and oxidation were kept to a minimum, were set as the standard thawing conditions to which the effects of temperature and oxygen were compared. The results indicate that temperature and oxygen exposure have negligible effects on the physicochemical characteristics of the solid particles. However, the chemical features of the solution (e.g., pH, electric conductivity, alkalinity, and concentration of major cations and trace elements) at 4℃ under oxic conditions were considerably altered, compared to those measured under the standard thawing conditions. This study shows that the thawing condition of ice wedge samples can affect their chemical features and thereby the geochemical information therein for the reconstruction of the paleoclimate and/or paleoenvironment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.611-616
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• 2001

Effects of high pressure and thermal pasteurization on the survival of microorganisms and quality changes of kochujang during 120 days of storage at 37$^{\circ}C$ were investigated. Viable cell counts were 1.43$\times$10$^{6}$ CFU/g in heat-treated, and 1.56$\times$10$^3$ CFU/g in pressure-treated, and decreased up to 3 log cycle, compared with 3.78$\times$10$^{6}$ CFU/g in the untreated kochujang. Viable cell counts decreased by the storage period at 37$^{\circ}C$. Viable cell counts decreased up to 2 log cycle from 3.78$\times$10$^{6}$ to 5.43$\times$10$^4$ CFU/g in the untreated kochujang, 4 log cycle from 1.43$\times$10$^{6}$ to 3.10$\times$10$^2$ CFU/g in heat-treated after 120 days of storage, while those in pressure-treated were not detected after 90 days from the initial stage of 1.56$\times$10$^3$ CFU/g. pH decreased significantly by the storage time. Titratable acidity increased significantly during storage, and pressure-treated kochujang showed lower values than heat-treated. Amino nitrogen content decreased significantly during storage, and pressure-treated kochujang showed higher values than heat-treated and lower values than the untreated. There were no significant changes in reducing sugar and ethanol content regardless of the treatment condition and the storage period. Hunter L, a and b values decreased significantly during storage. In the untreated kochujang, the changes in color accelerated compared with heat and pressure-treated.

• Journal of Korean Medical classics
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• v.24 no.4
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• pp.157-174
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• 2011

We derived following result by organizing research about processing of medicinal of before Han(漢) dynesty. The human being intake of natural substance for the purpose of treatment was what happened later than the use of natural substance as food. According to the record of by the early years of Shang(商) dynasty, we can assume that we cooked food with water and fire. The reason why there is no appearance of common production that can be included under the name of 'Tang Ye(湯液)' in the medical record discovered from Ma Wang Dui(馬王堆) is because 'Tang Ye' was yet developed. However, as the presentation of format of medicine process, there was gradual formation of medicinal fluid concept. There are quite of records on major details of cloth manufacture like washing and selection, grinding, processing of medicine from the recordings of "Wu Shi Er Bing Fang(五十二病方)", "Yang Sheng Fang(養生方)", "Za Liao Fang(雜療方)" discovered at Ma Wang Dui. It used words like 'Ze(擇)', 'Qu(去)' for the selection and 'Jiu(酒)', 'Zhuo(濯)' for the wash as a process method before cloth manufacture. When filter the processed medicine, it used words like 'Zhuo(捉)', 'Suo(索)', 'Jun(浚)' and used 'Yin Gan(陰乾)', 'Bao(暴)', 'Yang(暘)' for dry. The 'cutting(切削)' that crushes the medicine used different names based on the properties of medicines. The most frequent crush is 'Ye(冶)' and it means the powered medicine after dry. There was thermal process of mild fire(微火) and heating of 'Wen(溫)'. There are many states of medicine seen from the medical record discovered at Ma Wang Dui so they can be said as original medicine. 藥末劑 is relatively commercialized type then. Here, it includes later 湯劑 but there was no name such as 'decoction(湯)' or 'decoction of medical ingredients(湯液)'. Also, 'Fu Ju(㕮咀)' is the transformation of what was 'Fu Qie(父且)' at "Ja Liao Fang" of medical books of Ma Wang Dui with time flow. The original meaning of 'Fu Qie(父且)' is 'Fu Zu(斧俎)' and it means the crushing medicine with axe. The most important thing among the medical books of Han dynasty is "Shen Nong Ben Cao Jing(神農本草經)" and "Shang Han Za Bing Lun(傷寒雜病論)" of Zhang Zhong Jing(張仲景). "Shen Nong Ben Cao Jing" mentioned the dry method of medicine, collection and process production time, cooked and uncooked use of medicine and there are several types of medicine. Other than those, it mentioned 'Seven methods of combining herbs(七情合和)' to address cautions for combining medicines. Therefore, the 'processing of medicinal' in east Han dynasty period entered the theoretical step. However, there is only little recording on cloth manufacture of detailed medicine. From the "Shang Han Za Bing Lun" of Zhang Zhong Jing, the development in the way of 'processing of medicinal' reveled the cloth manufacture for each medicine. This tradition is continued until today and so it presents the development of purpose of 'processing of medicinal' is to greatly present the effect of medicine and to reduce the side-effect.

• Clean Technology
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• v.25 no.2
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• pp.129-139
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• 2019

Bamboo is an evergreen perennial plant, and it is known as one of the most productive and fastest-growing plants in the world. It grows quickly in moderate climates with only moderate water and fertilizer. Traditionally in Asia, bamboo is used for building materials, as a food source, and as versatile raw materials. Bamboo as a biomass feedstock can be transformed to prepare activated carbon using the thermal treatment of pyrolysis. The effect of process variables such as carbonization temperature, activation temperature, activation time, the amount of steam, and the mixing ratio of phosphoric acid and bamboo were systematically investigated to optimize the preparation conditions. Steam activation was proceeded after carbonization with a vapor flow rate of $0.8{\sim}1.8mL-H_2O\;g-char^{-1}\;h^{-1}$ and activation time of 1 ~ 3 h at $700{\sim}900^{\circ}C$. Carbon yield and surface area reached 2.04 ~ 20.59 wt% and $499.17{\sim}1074.04m^2\;g^{-1}$, respectively, with a steam flow rate of $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$ for 2 h. Also, the carbon yield and surface area were 24.67 wt% and $1389.59m^2\;g^{-1}$, respectively, when the bamboo and phosphoric acid were mixed in a 1:1 weight ratio ($700^{\circ}C$, 2 h, $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$). The adsorption of methylene blue into the bamboo activated carbon was studied based on pseudo first order and second order kinetics models. The adsorption kinetics were found to follow the pseudo second order model, which is governed by chemisorption.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.2
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• pp.47-56
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• 2008

The objective of this research is to evaluate the optimum recycling methods for the sewage sludge cakes at different microwave power-settings and for different periods of time. The dehydrated sewage sludge cakes used in this study was obtained from N wastewater treatment plan in the P City. The beginning drying processes were carried out in a microwave oven with 2,450 MHz frequency and power ranges of 1kW to 4 kW. The continuous conveyer drying system was also operated with 2,450 MHz frequency and power setting, ranging from of 1 kW to 6 kW. Initial moisture content of the sewage cake is 78~80%, and the moisture content decreased rapidly up to 0.2~2(wt%) within short periods due to breaking the cell walls. This study is also conducted to evaluate the characteristics of sewage sludge cakes with respect to important physical parameters effect on the thermal kinetics for evaporation water in the sludge which are operation times, moisture contents, drying rates, input amounts, flow rates and calorific values. It takes 60 minutes and 120 minutes to reach the critical moisture contents with power setting of 4 kW for 3kg/min and 6kg/min of the flow rates respectively. It takes 120 minutes and 110 minutes to reach the critical moisture contents with flow rates of 2.5 cm/min and sludge input of 6kg/min for the power settings of 4 kW and 6 kW respectively. The most effective value of the power for drying the sludge is 4 kW. Operation with 6kg/min and 4kW on 2cm of the sludge thickness can be effectively and inexpensively to reach the critical moisture contents, when you compare 2cm of the sludge thickness with 1cm and 3cm of the sludge thickness.

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.304-317
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• 2015

For the production of pumpkin paste with respect to heating conditions, we steamed the pumpkin for roughly 15 min, heated it with high pressure treatment for 0 min (A), 10 min (B), 20 min (C), 40 min (D), and subsequently investigated the quality characteristics. Generally a significant difference was observed between the pumpkin paste treated with and without high-pressure heat. The values of water content, crude protein and crude fiber of the high-pressure heat-treated groups B, C, D were decreased compared with untreated group A. The soluble fiber in experimental group B sweet-pumpkin paste treated with high-pressure heat for 20 min was higher than the control, and the highest value at 2.02. Experimental group D sweet-pumpkin paste treated with high-pressure heat for 40 min was found to have a decreased soluble fiber content relative to the control. The L value for the color of the group A untreated control sweet-pumpkin paste (no high-pressure heating) decreased as the time increased from 10 min to 40 min, with L values of 50.33, 49.46, and 48.06, respectively. The b value for the color of the sweet-pumpkin paste also decreased, showing a significant difference. Taking into account all the results, we chose experimental group B in order to prepare sweet-pumpkin latte. We used 0.2% gum (xanthan gum, locust bean gum, guar gum) as a stabilizer. Sweet-pumpkin latte with xanthan and locust bean gum has a suspension stability effect that lasts 90 min. The L and b values of sweet-pumpkin latte with gums increase and a value decrease compared with the control. In terms of the overall acceptance of the sweet-pumpkin latte, the experimental group with xanthan gum scored the best.

• Journal of Environmental Impact Assessment
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• v.29 no.3
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• pp.157-181
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• 2020

Sediments from rivers, lakes and marine ports serve as end points for pollutants discharged into the water, and at the same time serve as sources of pollutants that are continuously released into the water. Until now, the contaminated sediments have been landfilled or dumped at sea. Landfilling, however, was expensive and dumping at sea was completely banned due to the London Convention. Therefore, this study applied contaminated sedimentation soil of 'Royal Palace Livestock Complex' as soil purification method. Soil remediation methods were applied to pretreatment, composting, soil washing, electrokinetics, and thermal desorption by selecting overseas application cases and domestically applicable application technologies. As a result of surveying the site for pollutant characteristics, Disolved Oxigen (DO), Suspended Solid (SS), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) exceeded the discharged water quality standard, and especially SS, COD, TN, and TP exceeded the standard several tens to several hundred times. Soil showed high concentrations of copper and zinc, which promote the growth of pig feed, and cadmium exceeded 1 standard of Soil Environment Conservation Act. In the pretreatment technology, hydrocyclone was used for particle size separation, and the fine soil was separated by more than 80%. Composting was performed on organic and Total Petroleum Hydrocarbon (TPH) contaminated soils. TPH was treated within the standard of concern, and E. coli was analyzed to be high in organic matter, and the fertilizer specification was satisfied by applying the optimum composting conditions at 70℃, but the organic matter content was lower than the fertilizer specification. As a result of continuous washing test, Cd has 5 levels of residual material in fine soil. Cu and Zn were mostly composed of ion exchange properties (stage 1), carbonates (stage 2), and iron / manganese oxides (stage 3), which facilitate easy separation of contamination. As a result of applying acid dissolution and multi-stage washing step by step, hydrochloric acid, 1.0M, 1: 3, 200rpm, 60min was analyzed as the optimal washing factor. Most of the contaminated sediments were found to satisfy the Soil Environmental Conservation Act's standards. Therefore, as a result of the applicability test of this study, soil with high heavy metal contamination was used as aggregate by applying soil cleaning after pre-treatment. It was possible to verify that it was efficient to use organic and oil-contaminated soil as compost Maturity after exterminating contaminants and E. coli by applying composting.

• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.10-17
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• 2003

This study was carried out to analyze physicochemical characteristics of sericin cocoon from silkworm, Bombyx mori. The degumming loss increased with increasing treatment time up to 2 hr, and temperature up to 130$^{\circ}C$. At 130$^{\circ}C$, degumming loss of Nd-s jam and Nd$\^$H/ jam were 100% while that of Baegok jam was 24%. Nd-s jam and Baegok jam ha high glycine content of 29.1∼46.3 mol% where as Nd$\^$H/ jam had high serine content of 32.6 mol%. Thermal denaturation temperatures were found at 218$^{\circ}C$ for Nd-s jam, 216$^{\circ}C$ for Nd$\^$H/ jam, and 218$^{\circ}C$ for Baegok jam. Before degumming, crystallinities obtained by FT-IR analysis were 44.3, 43.7, and 59.9% for Nd-s jam, Nd$\^$H/ jam, and Baegok jam respectively. After degumming, crystallinity increased to 61.8% for Baegok jam. Before degumming, crystallinitics obtained from XRD were 35.9, 33.5, and 47.2%, for Nd-s jam, Nd$\^$H/ jam, and Baegok jam. After degumming, crystallinity increased to 49.8% for Baegok jam. The molecular weight of Nd$\^$H/ jam were 9,417 in 1 hr, 3,744 in 2 hr, 4,944 in hr, and 3,910 in 6 hr.