• Environmental Engineering Research
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• v.24 no.2
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• pp.202-210
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• 2019

In order to maximize the utilization of sewage sludge, a waste from wastewater treatment facility, the residual sewage sludge generated after lipid and carbohydrate extraction for biodiesel and bioethanol production was used to produce bio-oil by pyrolysis. Thermogravimetric analysis showed that sludge pyrolysis mainly occurred between 200 and $550^{\circ}C$ (with peaks formed around 337.0 and $379.3^{\circ}C$) with the decomposition of the main components (carbohydrate, lipid, and protein). Bio-oil was produced using a micro-tubing reactor, and its yield (wt%, g-bio-oil/g-residual sewage sludge) increased with an increase in the reaction temperature and time. The maximum bio-oil yield of 33.3% was obtained after pyrolysis at $390^{\circ}C$ for 5 min, where the largest amount of energy was introduced into the reactor to break the bonds of organic compounds in the sludge. The main components of bio-oil were found to be trans-2-pentenoic acid and 2-methyl-2-pentenoic acid with the highest selectivity of 28.4% and 12.3%, respectively. The kinetic rate constants indicated that the predominant reaction pathway was sewage sludge to bio-oil ($0.1054min^{-1}$), and subsequently to gas ($0.0541min^{-1}$), rather than the direct conversion of sewage sludge to gas ($0.0318min^{-1}$).

• Tribology and Lubricants
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• v.25 no.4
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• pp.236-242
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• 2009

Oil viscosity is one of the important parameters for machinery condition monitoring. Basically, it is expressed as kinematic viscosity measured by capillary flow and dynamic or absolute viscosity measured by rotary shear viscometry. Recently, acoustic wave techniques appear in the market, measuring viscosity as the product of dynamic viscosity and density. For Newtonian fluids, knowledge of density allows conversion from one viscosity parameter to the other at a specific shear rate and temperature. In this work, oil samples with different chain lengths of viscosity index (VI) improvers and concentrations were examined by different viscometric techniques. Results showed that acoustic viscosity measurements give misleading results for oil samples with high molecular weight VI improvers and at low temperatures ${\leq}40^{\circ}C$.

• Polymer(Korea)
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• v.29 no.1
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• pp.64-68
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• 2005

To recycle collected high-impact polystyrene (HIPS) wastes as liquid fuel, depolymerization characteristics of HIPS by pyrolysis was studied. The effects of temperature and time on the pyrolysis of HIPS were investigated. The depolymerization temperature and activation energy of HIPS pyrolysis increased with increasing heating rate. In general, conversion and liquid yield gradually increased with pyrolysis temperature and pyrolysis time. Each liquid product formed during pyrolysis was classified into gasoline, kerosene, light oil and heavy oil according to the distillation temperature based on the petroleum product quality standard of Korea Petroleum Quality Inspection Institute. As a result, the amount of liquid products produced during HIPS pyrolysis was in the order of gasoline》heavy oil〉kerosene〉light oil. Especially 51${\pm}$6 wt% of HIPS treated was obtained as gasoline.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.997-1003
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• 2006

An experiment with twenty crossbred goat kids (male) of 2-3 months old, weighing about 12 kg was conducted to study the effect of feeding formaldehyde treated rape seed oil cake based diet supplemented with molasses on growth rate and histopathological changes of different organs. Goats were randomly divided into four groups of 5 animals each and were individually fed for a period of 120 days. The animals in group I (URC) and II (URCM) were fed concentrate mixture (CM-I) containing untreated rape seed oil cake (30%) while, the animals in group III (TRC) and IV (TRCM) were offered concentrate mixture (CM-II) containing formaldehyde treated rape seed oil cake. Further, molasses as energy source was additionally supplemented with the concentrate mixture at the rate of 8% of concentrate mixture on dry matter basis to animals in group II and IV. All the animals were maintained on roughage (Berseem hay:wheat straw = 2:1) and concentrate in 50:50 ratio. Average daily gain (g/d) of animals in group IV was significantly (p<0.05) higher than that in group I., but at par with group II and III. Feed conversion efficiency was also significantly (p<0.05) higher in group IV (10.14) than group I and II but at par with group III. The growth rate however increased by 50.2% in group IV showing more consistency in maintaining highest growth rate due to better balance of nutrients. At the end of four months of feeding trial, two animals from each group were sacrificed for histopathological study of different organs. Significant histopathological changes in liver, heart, lungs tissue of animals fed untreated rape seed oil cake diet were recorded which were totally absent in the organ of animals fed formaldehyde treated cake. The liver tissue of goats receiving control diet (containing untreated rape seed oil cake) were found to be associated with engorged central vein and blood vessels. Hepatocytes were swollen, pale and degenerated with cellular infiltration and fibrosis of portal areas. The muscles of heart were found to have intermyofibral edema. Emphysema accompanied by dilated and ruptured alveoli was also recorded in lung tissue. However, histopathological examination of various tissues of goats fed formaldehyde treated cake diet did not exhibit any degenerative changes. Additional supplementation of molasses with or without treated cake diet, apparently did not have any significant effect on ameliorating the above degenerative changes.

• Journal of the Korean Applied Science and Technology
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• v.28 no.4
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• pp.455-463
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• 2011

The average sulfur content of crude oil is 2.2%. Coal is about 0.3 to 4.0 percent of the sulfur gases or particles being discharged into the atmosphere through the chimney as 1 to 2% $SO_3$(Sulfur trioxide) and about 95% of the $SO_2$ is reported. $SO_3$ gas, which has many different causes of, as the combustion of sulfur containing fuel during the air due to the excess $SO_2$ gas is oxidized to $SO_3$ gas. Sulfur trioxide emitted from high sulfur heavy oil fired boiler caused white plume in stack and high temperature and cold end corrosion of facilities. So, in order to control sulfur trioxide concentration of Fuel gas in boiler, various of additives are used in other foreign. They are injected to Fuel Oil and consumed in boiler and reduce ash and the conversion rate of sulfur trioxide. In domestic, MgO compounds are used as additives but the total volume of them are made from other foreign company. In this study, MgO compounds were developed with liquid MgO compounds and field application was accomplished. The effect of newly developed chemicals and process were nearly equal to foreign products. In Consequent, the chemicals and process produced by newly developed technology can be substituted for foreign products and reduce the cost of plant operation.

• KSBB Journal
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• v.11 no.6
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• pp.654-662
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• 1996

Bacterial strains which degrade crude oil were isolated by liquid culture from oil-spilled soil, and four isolates were selected among them. The strain Hl7-1 was finally selected after testing emulsifying activity and oil conversion rate. The strain Hl7-1 was identified as a Nocardia sp. based on the test for morphological, biochemical and physiological characteristics. It appears to be highly specialized for growth on crude oil in minimal salts medium since it showed preference for oil or degradation products as substrates for growth. It was found that it could grow on at least fifteen different hydrocarbons. The optimum cultural and environmental conditions were seeked. Cell growth and emulsification activity as a function of time were also determined. Crude oil degradation and the reduction of product peak was identified by the analysis of remnant oil by gas chromatography after 3 days of cultivation. Approximately 83% of oil were converted into a form no longer extractable by organic solvents.

• Clean Technology
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• v.23 no.1
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• pp.54-63
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• 2017

Volatile organic compounds (VOCs) are widely used in both industrial and domestic activities. VOCs are one of the most unpleasant, frequently complaint-rousing factors of pollution around the world. It is now necessary to research and develop an alternative technology that could overcome the problems of the existing odor-control and VOC-eliminating techniques. In this study, essential oil and photocatalytic process was applied in the removal of benzene and toluene, typical VOCs in petrochemistry plant. therefore, this study conducted experiments on the selection of appropriate essential oil, photodegradation, hydroxyl radical generation capacity. The removal efficiency and reaction rate were performed to selecte the type and concentration of essential oil. As a result, removal efficiency of Hinoki Cypress oil was approximately 70% and reaction rate of Hinoki Cypress was high. The results of photolysis experiment, photocatalytic oxidation process showed that the decomposition efficiency of VOCs increased considerably with increasing UV lamp power. In addition, the conversion of VOCs was increased up to $0.1gL^{-1}$ photocatalysts. The hydroxyl radicals measure was performed to determine the ability to generate hydroxyl radicals. The analytical result showed that high $TiO_2$ concentration and lamp power was produced many hydroxyl radical. Experiments of the removal efficiency and reaction rate were performed using essential oil and photooxidation. As a result, the removal efficiency showed that the removal efficiency was increased high temperature and reaction time. The activation energy was calculated from the reaction rate equation at various temperature condition. Activation energy was approximately $18kJmol^{-1}$.

• Korean Journal of Poultry Science
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• v.33 no.2
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• pp.141-149
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• 2006

An experiment was conducted to investigate the effects of dietary acidifier($Lactacid^(R)$) and essential oil($Immunocin^(R)$) on the performance, nutrient metabolizability, small intestinal microflora, IgG level and leukocytes and erythrocytes in broiler chickens. Five hundred males and 500 females broiler chickens($Ross^(R)$) were divided into 20 pens of 50 chickens(25 birds in each sex). Five pens were assigned to each of four dietary treatments: control, diets containing antibiotics(Bacitracin methylene disalicilate), acidifier($Lactacid^(R)$) and essential oil($Immunocin^(R)$) dietary treatments. Birds were fed experimental diets ad libitum 5 wks. Weight gain, feed intake, and feed conversion rate were significantly affected by dietary treatment(P<0.05). Overall weight gain($0{\sim}5$ wks) of $Lactacid^(R)$ treatment was significantly lower than the others. Feed intake was highest(P<0.05) in the control followed by antibiotics, $Lactacid^(R)\;and\;Immunocin^(R)$ treatment. Feed conversion rate of $Immunocin^(R)$ treatment was lowest(P<0.05) followed by antibiotics, $Lactacid^(R)$ treatment and the control. Production indices of $Immunocin^(R)$ and antibiotics treatments were significantly higher than those of the control and $Lactacid^(R)$ treatment(P<0.05). $Immunocin^(R)$ treatment was the highest and antibiotics was lowest in serum IgG level. The number of leukocytes and stress index(neutrophil/lymphocytes) tended to be lower in $Immunocin^(R)$ treatment than others. There were no significant differences in erythrocytes among the treatments. The cfu of E. coli was significantly lower in $Immunocin^(R)$ and antibiotics treatments than $Lactacid^(R)$ treatment and the control. Metabolizability of crude protein was significantly lower in the control than $Lactacid^(R)\;and\;Immunocin^(R)$ treatment while that of NFE was significantly lower in $Immunocin^(R)\;than\;Lactacid^(R)$ and antibiotics treatments. It was concluded that essential oil product $Immunocin^(R)$ is as effective as antibiotics in improving feed conversion efficiency and production index while $Lactacid^(R)$ is not.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.4
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• pp.225-230
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• 2002

Experiments on deactivation kinetics of immobilized lipase enzyme from Candida cyl-indracea were performed in stirred bath reactor using rice bran oil as the substrate and temperature as the deactivation parameter. The data were fitted In first order deactivation model. The effect of temperature on deactivation rate was represented by Arrhenius equation. Theoretical equations were developed based on pseudo-steady state approximation and Michaelis -Menten rate expression to predict the time course of conversion due to enzyme deactivation and apparent half-life of the immobilized enzyme activity in PFR and CSTH under constant feed rate polity for no diffusion limitation and diffusion limitation of first order. Stability of enzyme in these continuous reactors was predicted and factors affecting the stability were analyzed.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.6
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• pp.1055-1061
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• 2000

The kinetics of tar formation has been studied experimentally and modeled mathematically for waste lubricating oil after pyrolyzed at batch reactor. And stabilization of pyrolyzed oil has been studied. A combination of series and parallel reaction was assumed for the mechanism of tar formation. From the proposed kinetic model, pyrolyzed oil to tar was found to be rate limiting step for tar formation. It was found that the fly ash and coke had the ability to remove materials of tar formation and to protect oxidation of pyrolyzed oil.