• Journal of the Korea Organic Resources Recycling Association
• /
• v.22 no.2
• /
• pp.11-16
• /
• 2014

Korea is the urgent need to diversify the bio-energy raw materials because we have narrow area of land cultivated plants and lack the bio-mass resources. Using a resource-rich the marine environment enclosed on three sides by the sea. Through bio-energy production-technical and carbon dioxide reduction measures which will be a very effective alternative. Sustainable development about algae bio-energize industry through SSaM-GG(Smart, Shared and Mutual-Green, Growth) is expected. Algae has high carbon dioxide absorption factor, extracting oil from algae is thirty times much more than sunflower.

• KSBB Journal
• /
• v.30 no.4
• /
• pp.161-165
• /
• 2015

Lactic acid and its derivatives are widely used in the food, pharmaceutical, and cosmetic industries. It is also a major raw material for the production of poly-lactic acid (PLA), a biodegradable and environmentally friendly polymer and a possible alternative to synthetic plastics derived from petroleum. For PLA production by new strains of lactic acid bacteria (LAB), we screened LAB isolates from shellfish. A total of 51 LAB were isolated from 7 types of shellfishes. Lactic acid production of individual isolates was examined using high-performance liquid chromatography using a Chiralpak MA column and an ultraviolet detector. Lactobacillus plantarum T-3 was selected as the most stress-resistant strain, with minimal inhibition concentrations of 1.2 M NaCl, 15% ethanol, and 0.0020% hydrogen peroxide. In a 1 L fermentation experiment, $\small{D}$-lactic acid production of 19.91 g/L fermentation broth was achieved after 9 h cultivation, whereas the maximum production of total lactic acid was 41.37 g/L at 24 h.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.05a
• /
• pp.47-48
• /
• 2023

In the domestic industrial sector, greenhouse gases emitted from the cement industry account for about 10%, with most of them generated during the cement clinker calcination process. During the calcination process, 57% of carbon dioxide is emitted from the decarbonation reaction of limestone, 30% from fuel consumption, and 13% from electricity usage. In response to these issues, the cement industry is making efforts to reduce carbon dioxide emissions by developing technologies for raw material substitution and conversion, improving process efficiency by utilizing low-carbon alternative heat sources, developing CO₂ capture and utilization technologies, and recycling waste materials. In addition, due to the limitations in purchasing and storing industrial byproducts generated from industrial facilities, many studies are underway regarding the recycling of construction waste. Therefore, this study analyzes the manufacture of calcium silicate cement (CSC), which can store carbon dioxide as carbonate minerals in industrial facilities, and aims to contribute to the development of environmentally friendly regenerated cement using construction waste.

• Korea Trade Review
• /
• v.45 no.5
• /
• pp.117-139
• /
• 2020

In case of international long-term transactions, there are various risks of economic change of circumstances including skyrocketing price increase and shortage of raw material, as well as force majeure in a general sense. Nevertheless, pretty many of international long-term commercial contracts do not include the provisions of renegotiation and adaptation of the contract. In this case, possibility of renegotiation and adaptation depends mainly on the applicable law. Namely, it may be possible or not, according to choice of law. The reason is that national laws have nuances each other, and most of national courts are traditionally reluctant to accept hardship. and also, provisions of international uniform law (CISG) has ambiguity and inflexibility in relation to the problems of change of circumstances. Accordingly, this paper analyzes comparatively the doctrines and provisions related to renegotiation and adaptation of contracts of the most representative countries such as England, U.S.A., France, Germany as well as provisions CISG and soft law such as PICC. By doing so, the author makes clear which laws of instruments is more flexible or acceptable in allowing renegotiation and adaptation of long-term commercial contracts, and emphasizes on the importance of inclusion of express terms by using other alternative supplementing clauses, as a best solution for settling the problems of legal uncertainty of contract in relation to renegotiation and adaptation.

• Journal of Korean Society of Environmental Engineers
• /
• v.36 no.7
• /
• pp.514-520
• /
• 2014

In this study, the production potential of alternative coagulant ($Al_2(SO_4)_3$ solution) having the identical coagulation activity with respect to the commercial coagulant was investigated. The raw material of alternative coagulant was a spent catalyst including aluminium (waste activated alumina) generated in the manufacturing process of the polymer. The alternative coagulant was produced through a series of processes: 1) intense heat and grinding, 2) chemical polymerization and substitution with $H_2SO_4$ solution, 3) dissolution and dilution and 4) settling and separation. To determine the optimal operating conditions in the lab-scale autoclave and dissolver, the content of $Al_2O_3$ in alternative coagulant was analyzed according to changes of the purity of sulfuric acid, reaction temperature, injection ratio of sulfuric acid and water in the dissolver. The results showed that the alternative coagulant having the $Al_2O_3$ content of 7~8% was produced under the optimal conditions such as $H_2SO_4$ purity of 50%, reaction temperature of $120^{\circ}C$, injection ratio of $H_2SO_4$ of 5 times and injection ratio of water of 2.3 times in dissolver. In order to evaluate the coagulation activity of the alternative coagulant, the Jar-test was conducted to the effluent in aerobic reactor. As a result, in both cases of Al/P mole of 1.5 and 2.0, the coagulation activity of the alternative coagulant was higher than that of the existing commercial coagulant. When the production costs were compared between the alternative and commercial coagulant through economic analysis, the production cost reduction of about 50% was available in the case of the alternative coagulant. In addition, it was identified that the alternative coagulant could be applied at field wastewater treatment plant without environmental problem through ecological toxicity testing.

• Applied Chemistry for Engineering
• /
• v.19 no.2
• /
• pp.199-204
• /
• 2008

Hemicellulose, consisteing of pentose as xylose and mannose, is usable as high octane fuels and heavy oil additives if depolymerized to monomer unit. In this study, thermochemical degradation by pyrolysis-liquefaction of hemicellulose, the effects of reaction temperature, conversion yield, degradation properties and degradation products were investigated. Experiments were performed in a tube reactor by varying reaction temperatures from $200^{\circ}C$ to $400^{\circ}C$ at 40 min of reaction time. The liquid products from pyrolysis-liquefaction of hemicellulose contained various kinds of ketones. Ketones, as 2,3-dimethyl-2-cyclopenten-1-one, 2,3,4-trimethyl-2-cyclopentan-1-one, and 2-methyl-cyclopentanone, could be used as high-octane-value fuels and fuel additives. However, phenols are not valuable as fuels. Combustion heating value of liquid products obtained from thermochemical conversion processes of hemicellulose was in the range of 6,680~7,170 cal/g. After 40 min of reaction at $400^{\circ}C$ in pyrolysis-liquefaction of hemicellulose, the energy yield and mass yield were as high as 72.2% and 41.2 g oil/100 g raw material, respectively.

• Journal of the Korean Applied Science and Technology
• /
• v.34 no.4
• /
• pp.727-736
• /
• 2017

In this study, the method of evaluation of moisturizing ability of cosmetics using specimens was studied as an alternative method of clinical tests. Cosmetic spreadability, surface drying, and moisture loss rate of four specimens (Japanese cake (Maru mochi), Garaetteok, wheat flour, and agar) were evaluated. Also, the water loss rate of the specimens and the transepidermal waterloss were analyzed for 10 kinds of lip make-up products (5 kinds of lipstick, 3 kinds of lip balm, 2 kinds of lip gloss). The moisture loss rate (moisture evaporation sensitivity) of the agar specimen was highest in the order of agar> Garaetteok> Japanese cake> wheat flour. Agar specimens are the most suitable in terms of spreadability, surface crack, and raw material supply. Containers for the preparation of agar specimens are suitable for plastic materials with low heat transfer, which can produce convex, smooth surface specimens. In the evaluation of moisturizing ability of lip makeup products, there was a strong correlation between the water loss rate and the transepidermal waterloss rate measured with agar specimens. These results show that the proposed method can be used as one of the useful alternative test methods.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.39 no.3
• /
• pp.147-155
• /
• 2016

Industry 4.0's goal is the 'Smart Factory' that integrates and controls production process, procurement, distribution and service based on the fundamental technology such as internet of the things, cyber physical system, sensor, etc. Basic requirement for successful promotion of this Industry 4.0 is the large supply of semiconductor. However, company I who produces dicing blades has difficulty to meet the increasing demand and has hard time to increase revenue because its raw material includes high price diamond, and requires very complex and sensitive process for production. Therefore, this study is focused on understanding the problems and presenting optimal plan to increase productivity of dicing blade manufacturing processes. We carried out a study as follows to accomplish the above purposes. First, previous researches were investigated. Second, the bottlenecks in manufacturing processes were identified using simulation tool (Arena 14.3). Third, we calculate investment amount according to added equipments purchase and perform economic analysis according to cost and sales increase. Finally, we derive optimum plan for productivity improvement and analyze its expected effect. To summarize these results as follows : First, daily average blade production volume can be increased two times from 60 ea. to 120 ea. by performing mixing job in the day before. Second, work flow can be smoother due to reduced waiting time if more machines are added to improve setting process. It was found that average waiting time of 23 minutes can be reduced to around 9 minutes from current process. Third, it was found through simulation that the whole processing line can compose smoother production line by performing mixing process in advance, and add setting and sintering machines. In the course of this study, it was found that adding more machines to reduce waiting time is not the best alternative.

• Journal of the Korean Applied Science and Technology
• /
• v.30 no.4
• /
• pp.688-700
• /
• 2013

The potential of biodiesel production technology using lipids extracted from sewage sludge was investigated. Despite the bright prospect of biodiesel production, efforts to commercialize it have been very limited. One of the major obstacles has been the high price associated with refined oil feedstock, which makes up nearly 70-75% of the total production costs. Hence, in order to reduce the cost of biodiesel production, using cheaper feedstock such as waste oil or low-quality oil has been proposed. Especially, sewage sludge, a relatively inexpensive feedstock, is a promising raw material for such a purpose. In this study, it is aimed to review biodiesel production technology from sewage sludge as a lipid feedstock. It is process modifications to combine the oil extraction steps, fuel conversion steps (i.e. in situ transesterification, thermo-chemical process with non-catalytic heterogeneous biodiesel production) and fuel quality from sewage sludge.

• The Korea Journal of Herbology
• /
• v.30 no.4
• /
• pp.21-27
• /
• 2015

Objectives : In this study, we investigated the biological activities such as anti-obesity using Samwondan ethanol extract (SWD). SWD is a complex with Salicornia herbacea Linnaeus, Saururus chinensis Baill and Houttuynia cordata Thunberg as the main raw material.Methods : The SWD was extracted 80% ethanol. 3T3-L1 preadipocytes were induced adipogenesis by differentiation media with SWD at 1 μg/mL, 10 μg/mL, and 100 μg/mL. Effect of SWD performed using MTT assay, oil red O staining (observation by microscope), and reverse transcription polymerase chain reaction. Also we measured production of triglyceride (TG), fatty acid, and acetyl-CoA carboxylase (ACC).Results : Non-cytotoxicity was in all test group from range of 1 μg/mL to 100 μg/mL on pre-adipocyte. The droplet and production of lipid were decreased significantly by the SWD. And TG was decreased by approximately 89%, 85% and 82%, upon the SWD treatment at concentration of 1 μg/mL, 10 μg/mL, and 100 μg/mL. Moreover, the SWD showed inhibitory effects on the expression of the C/EBP (CCAAT/enhaner binding protein)β, C/EBPα, and peroxisome proliferator-activated receptorγgenes in adipocytes. The SWD at 100 μg/mL concentration showed inhibitory effect on fatty acid production by 79%. Also ACC production were decreased dose-dependently.Conclusions : From the results above, we concluded that the SWD indicated significantly anti-obesity effects.