• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.312-318
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• 1990

The effects of blanching, homogenization and heat sterilization on the stability of soymilk suspension were investigated by determination of nitrogen solubility index(NSI) of suspension and measuring the volume of precipitates and cream separated. The results obtained were that the NSI was decreased as the blanching temperature increased from $50^{\circ}C\;to\;80^{\circ}C$. The soybean particles having $8{\mu}$ by grinding showed more stable soymilk than that of $53{\mu}$. The stability was increased as the homogenizing pressure increased to $200kg/cm^2$ and repeated homogenizing process gave more stability than single one. The sterilization resulted a significant decrease in stability as it was heated at $120^{\circ}C-125^{\circ}C$ for more than 30 minutes.

• Journal of the Korea Institute of Building Construction
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• v.17 no.6
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• pp.517-525
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• 2017

Red mud is an industrial by-product produced during the manufacturing aluminum hydroxide ($Al(OH)_3$) and aluminum oxide($Al_2O_3$) from Bauxite ores. In Korea, approximately 2 tons of red mud in a sludge form with 50% moisture content is produced when 1ton of $Al_2O_3$ is produced through the Bayer process. In the paper, dispersion characteristics of liquefied red mud that does not require heating and grinding process for recycling were investigated through viscosity and sediment index. The results showed that the sediment index of liquefied red mud increased but viscosity of that decreased with a higher W/R ratio. Also we proposed the range of initial viscosity from 2000cP to 8000cP and target sedimentation index below 20% at elapsed time 180days for stable dispersion of liquefied red mud.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.333-340
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• 2019

Red mud is an industrial by-product produced during the manufacturing aluminum hydroxide (Al(OH)3) and aluminum oxide(Al2O3) from Bauxite ores. In Korea, aproximately 2 tons of red mud in a sludge form with 50% moisture content is produced when 1ton of Al2O3 is produced through the Bayer process. Neutralization of red mud will help to reduce the environmental impact caused due to its storage and also lessen significantly the ongoing management of the deposits after closure. It will also open opportunities for re-use of the residue which to date have been prevented because of the high pH. Moreover, attention to liquefied red mud(LRM) that does not require heating and grinding process for recycling is needed. In this paper, characteristics of compressive strength for cement paste with content of LRM neutralized by nitric acid and sulfuric acid. The results showed that compressive strength of cement paste with neutralized LRM is higher than that of cement paste with LRM.

• Journal of the Korean Ceramic Society
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• v.40 no.8
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• pp.804-810
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• 2003

The fine powder produced by heating and grinding of the waste concrete in the waste construction was investigated whether utilize as substitution raw material of SiO$_2$, CaO, and Al$_2$O$_3$ source for OPC clinker manufacture is possible or not. In order to synthesize OPC clinker, limestone, shale, converter slag and fly ash were used as main raw materials, and modulus was fixed LSF 91.0, SM 2.60, IM 1.60. The synthesized clinkers were characterized. The Main products of synthesized clinker were C$_3$S, ${\beta}$-C$_2$S, C$_3$A, C$_4$AF as OPC clinker at 1,43$^{\circ}C$. As a result of TG-DTA and burnability index(B.U) analysis of each raw mixtures, the formation temperature of clinker phases was similar and B.I was showed easy burning as 48.6∼51.4.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.439-444
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• 1990

Fourteen varieties of soybeans grown in Korea were investigated for their chemical composition, yields and organoleptic properties of soybean curd. The soybean curd was prepared by soaking, grinding and heating of soybeans followed by filtration, coagulation with $CaSO_4$ and pressing. The proximate analysis showed that soybean curd had the moisture content of $75.0{\sim}82.0%\;and\;48.6{\sim}56.1%\;protein,\;14.8{\sim}40.4%\;lipids\;and\;6.4{\sim}26.8%$ carbohydrate by dry weight basis. The yield of volume total solids and protein from 100g of soybeans were $182.2{\sim}227.5cm^3,\;42.65{\sim}55.60%\;and\; 57.90{\sim}76.50%$, respectively. Among the 14 varieties, the highest volume yield was obtained from Suwon-141 which has the highest contents of moisture, carbohydrate and the lowest in lipids of soybean curd. The curd prepared with Baegun and Jangyeob contained relatively low values in moisture, protein and carbohydrate and yielded the lowest in volume yield. Therefor moisture, protein and carbohydrate contents in soybean curd affected greatly on volume yield. The organoleptic properties of odor and taste couldn't find any significant relationship with chemical composition of soybean curd eventhough there were some difference in their intensities among varieties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.137-141
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• 1979

A study on the processing of soy curd powder with soybean milk and kril autolasate has been carried out to prolong tile self life and to improve the taste and colour of soy curd. The soy curd was manufactured by coagulation of the soybean milk prepared from soybean through a series of processes of soaking, grinding, heating at $500^{\circ}C$ for 5 minutes and filtration. Ten hours was reasonable as the soaking time of the soybean for the high yield of soybean milk. The use of $3\%$ $glucono-\delta-lactone$ to the weight of the raw soybean showed the best coagulation of the soybean milk at $90^{\circ}C$ in relation to the yield and content of crude protein of the soy curd. The soy curd powder prepared by spray drying of soyben milk could be coagulated at $90^{\circ}C$ by the addition of $glucono-\delta-lactone$ after suspending in water. The powder manufactured by spray drying of the mixture of soybean milk and drill autolasate could also be coagulated under the same conditions to produce the soft soy curd. Another powder prepared by spray drying of the mixture of soybean milk, krill autolysate and $glucono-\delta-lactone$ could be coagulated by standing at room temperature after 2 minutes boiling.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.362-367
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• 2006

Waste activated sludge(WAS) collected from domestic wastewater treatment plant is biomass that contains large quantities of organic matter. However, relevant literature show that the bio-hydrogen yield using WAS was too low. In this study, the effect of pretreatment of WAS on hydrogen yield was investigated. Pretreatment includes acid and alkali treatments, grinding, heating, ozone and ultrasound methods. After pretreatment organic matters of WAS were solubilized and soluble chemical oxygen demand(SCOD) was increased by 14.6 times. Batch experiments were conducted to investigate the effects of pre-treatment methods and buffer solution, hydrogen partial pressure, and sodium ion on hydrogen production from WAS by using heated anaerobic mixed cultures. Experimental results showed that addition of buffer solution, efficient pre-treatment method with alkali solution, and gas sparging condition markedly increased the hydrogen yield to 0.52 mmol $H_2/g$-DS.

• International Journal of Ocean System Engineering
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• v.2 no.3
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• pp.185-194
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• 2012

A Macroscopic combination of two or more distinct materials is commonly referred to as a "Composite Material", having been designed mechanically and chemically superior in function and characteristic than its individual constituent materials. Composite materials are used not only for aerospace and military, but also heavily used in boat/ship building and general composite industries which we are seeing increasingly more. Regardless of the various applications for composite materials, the industry is still limited and requires better fabrication technology and methodology in order to expand and grow. An example of this is that the majority of fabrication facilities nearby still use an antiquated wet lay-up process where fabrication still requires manual hand labor in a 3D environment impeding productivity of composite product design advancement. As an expert in the advanced composites field, I have developed fabrication skills with the use of machinery based on my past composite experience. In autumn 2011, the Korea government confirmed to fund my project. It is the development of a composite sanding machine. I began development of this semi-robotic prototype beginning in 2009. It has possibilities of replacing or augmenting the exhaustive and difficult jobs performed by human hands, such as sanding, grinding, blasting, and polishing in most often, very awkward conditions, and is also will boost productivity, improve surface quality, cut abrasive costs, eliminate vibration injuries, and protect workers from exposure to dust and airborne contamination. Ease of control and operation of the equipment in or outside of the sanding room is a key benefit to end-users. It will prove to be much more economical than normal robotics and minimize errors that commonly occur in factories. The key components and their technologies are a 360 degree rotational shoulder and a wrist that is controlled under PLC controller and joystick manual mode. Development on both of the key modules is complete and are now operational. The Korean government fund boosted my development and I expect to complete full scale development no later than 3rd quarter 2012. Even with the advantages of composite materials, there is still the need to repair or to maintain composite products with a higher level of technology. I have learned many composite repair skills on composite airframe since many composite fabrication skills including repair, requires training for non aerospace applications. The wind energy market is now requiring much larger blades in order to generate more electrical energy for wind farms. One single blade is commonly 50 meters or longer now. When a wind blade becomes damaged from external forces, on-site repair is required on the columns even under strong wind and freezing temperature conditions. In order to correctly obtain polymerization, the repair must be performed on the damaged area within a very limited time. The use of pre-impregnated glass fabric and heating silicone pad and a hot bonder acting precise heating control are surely required.

• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.211-218
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• 2007

This study was carried out to develop the technique for manufacturing activated carbon from livestock manure and to analyse it's odor absorptiveness. Each of layer manure(LM), litter from broiler house(BL) and litter from dairy barn(DL), compost from layer manure(LC) and pig manure(PC), and coconut shell(CS) was used as a raw material. Activated carbon by grinding the raw material, adding the coal tar as a binder, palletizing, drying, heating with $N_2$ gas at $400^{\circ}C$ for 1 hour, activating by reaction with steam at a temperature of $750^{\circ}C$ for 1 hour. Moisture contents of raw material was 44.9% in layer compost, 71.9% in layer manure, 24.4% in broiler litter, 47% in pig manure compost and 33.9% in dairy litter. Volatile matter in layer compost, layer manure, broiler litter, pig manure compost and dairy litter was 18.8%, 31.0%, 49.8%, 22.3% and 11.6%, respectively. Surface area(BET) of activated carbon from layer compost, layer manure, broiler litter, pig manure compost, dairy litter and coconut shell was 259.8, 209.8, 63.5, 442.3, 812.9 and $1,040\;m^2/g$, respectively. Activated carbon made by livestock manure or litter were examined with scanning electron microscope, and micropore was a type of sponge like particles honeycombed with chambers. Pore size of activated carbon was ranged from 0.39 to $5.02\;{\AA}$, but coconut shell was $0.30\;{\AA}$. Iodine absorptiveness of activated carbon from livestock manure was $530{\sim}580mg/g$. But activated carbon made by coconut shell was 1000 mg/g. Each activated carbon could absorb odor compound very well. Absorptiveness of activated carbon from layer manure for hydrogen sulfide and trimethyl amino was 74.5% and 73.9% at the accumulated flux of 60,000 ml, but, in the case of ammonia was only 15.2% at the accumulated flux of 10,000 ml

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.302-308
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• 1997

The purpose of this study was to investigate the extraction yield and quality stability as to the oleoresin process with large amount of onion at one time. The first mixed-product is raw onion juice which was reduced the compression and concentrated by Brix 70% mixed together wit the residue which was extracted and concentrated by ethanol, the second product manufactured by the same method above after the autoclaving with onion, and the other product is made by grinding by 50mesh to freeze-dried onion. Each of yields were 7.3, 9.1 and 0.8% and each of total sugar content was 616.4, 712.3 and 150.3mg/g. Therefore the product extracted by ethanol from freeze-dried onion was very low in yield and total sugar content. By the index of the overall odor intensity, contents of total pyruvate were 1,733.7, 520.6, and 2,716.5$\mu\textrm{g}$/g for each product. As a result, oleoresin onion processing that desired to use raw onion was remarkable for odor recovery. For the homogenous mixture with concentrate of onion juice and ethanol extract were emulsified by the addition of 2% of PGDR(polyglycerol condensed ricinoleate) and agitation(10,000rpm, 30 minutes). At this time, interfacial tension was 1.9 dyne/cm and the formation of emulsion was for 96.2% when left over 24hours in 6$0^{\circ}C$. When it was to be centrifuged(2,000$\times$G, 80 minutes) after emulsification, the volume of emulsion level without seperation was 92.6%, and very high in emulsification stability. The induced heating-oxidize with soy bean oil and sesame oil added to 1% of onion oleoresin, induction-time extension effect appeared with antioxidant activity that was applicable for 80.8~82.2% as to the effect of addition of 0.02% BHA.