• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.2
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• pp.107-115
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• 2009

Lately, the length of tunnel, the number of large-long tunnel over three lanes are steeply increased because of the request for high speed and straight road. Therefore, the maximization of excavation efficiency is needed in tunnel construction. Bulk Emulsion explosives charging system is the spearhead equipment using the radio remote control $&$ mechanization system compare with a traditional method Cartridge type. This study introduced the bulk emulsion explosives which is new method in tunnel blasting and verified the efficiency of bulk emulsion explosives for long-large tunnel. And we tried to compare Cartridge type efficiency with bulk emulsion explosives efficiency by the field test.

• Explosives and Blasting
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• v.26 no.2
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• pp.64-76
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• 2008

Bulk Emulsion blasts using mechanized charging system, which is generally used in foreign countries, have recently introduced and gradually increased in Korea. The Bulk Emulsion are safe and able to increase the charging density for improvement of fragmentation and advancement especially in tunneling, and minimizing environmental problem. Because of less toxic gas generation, the explosives are called, namely ech-friendly products. There are two kinds of Bulk Emulsion; one is for open cut and the other is for tunneling. According to features of blast sites and its purpose, the compositions are different, but the principle is the same. In this study, trial blasts using Bulk Emulsion for tunneling had executed at 10 sites in Korea. The major result of the major job-sites is the following. First of all, compared with cartridge explosive, Bulk Emulsion was able to increase its charging density up to $35{\sim}60%$, to decrease the blast holes to approximately $10{\sim}30%$ down, and the advancement was improved up to $8{\sim}20%$ and also 30% up in its fragmentation. Toxic gas production after cartridge blasting showed 34.44ppm of its CO. Bulk Emulsion, however, showed 20.13ppm, which was 58.45% production of the cartridge explosive, and NOx was below 2ppm. The mechanized charging system of Bulk Emulsion should be applied to large sized tunnel blasting, long advanced tunnel which can secure the advancement of over $4{\sim}5m$, and the sites required finishing rapidly.

• Explosives and Blasting
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• v.19 no.3
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• pp.39-47
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• 2001

Bulk-Emulsion system은 미주나 서구 유럽 등지의 발파분야에 있어 선구적인 역할을 수행하여 왔던 나라에서는 이미 보편화된 시스템으로 ANFO 다음으로 노천이나 터널 굴진에 널리 적용되고 있다. Bulk-Emulsion system은 제조, 저장, 운반 및 사용에 있어서 극히 안전하고 장전밀도를 증가시켜 효과적인 파쇄와 굴진률 향상을 기대할 수 있으며 발파 후가스가 매우 양호한것을 비롯하여 기계화 장전에 따른 시공 능률 향상과 작업 안전성 강화 등 많은 장점을 가지고 있다. 본 연구에서는 고속도로 터널 현장에 국내 최초로 터널용 Bulk-Emulsion system을 이용하여 총 15회에 걸쳐 시험발파를 실시하였으며 이 결과를 토대로 하여 Bulk-Emulsion system 적용에 따른 효과와 문제점을 알아보고자 하였다.

• Explosives and Blasting
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• v.25 no.2
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• pp.61-70
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• 2007

Korean large limestone mines started to employ bulk emulsion explosives to improve the productivity in early 2000s. As the application of the bulk emulsion explosives became common in the mid 2000s, the bulk emulsion application increases overall performance but it tends to decrease the moving and heaving because it lacks in gas volume and heat energy. Therefore, the chemical gassing technique was introduced to improve the blasting efficiency of the existing bulk emulsion explosives. The chemical gassing is a technique to replacing GMB(Glass Micro Balloon), which is used for a sensitizer, with gassing agent to chemically sensitize it. This paper introduces the case of successful application of chemical gassing in a Korean large limestone mine. We also compared and evaluated the blast and work efficiency between bulk emulsion GMB & gassing agent (chemical gassing). The results indicate that the replacement of GMB with gassing agent improved fragmentation in the upper part and toe of a bench as well as moving efficiency of the material.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1077-1083
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• 1999

This study was aimed to evaluate the effectiveness of hydrophilic, lipophilic antioxidants and emulsifiers by HLB (hydrophilic lipophilic balance) in different oil systems. Lipophilic antioxidant (${\delta}-tocopherol$), hydrophilic antioxidant (gallic acid) and emulsifier(lecithin, tween 20, span 60) were evaluated in relation to oil stability in bulk oil system (soybean oil) and emulsified with Tween 80 at $60^{\circ}C$. In the storage test ($60^{\circ}C$), gallic acid was more effective on the stability of oil oxidation than ${\delta}-tocopherol$ in bulk and emulsion system. Lecithin as a hydrophilic emulsifier was more effective than tween 20 on the stability of oil oxidation in bulk and emulsion system. Also span 60, a lipophilic emulsifier, was more effective than tween 20, a hydrophilic emulsifier, in bulk and emulsion systems.

• Proceedings of the KSEE Conference
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• 2004.08a
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• pp.77-95
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• 2004

• Explosives and Blasting
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• v.24 no.1
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• pp.29-37
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• 2006

The demand of the bulk emulsion explosives is being increased more and more by using the mechanization loading system in a domestic tunnel sites. Thus, a rational design criteria that is suitable for rock and circumstance condition has been required. In this study, authors investigated a optimum specific charging weight and resonable charging weight based on domestic blasting construction cases, which were performed by using a mechanization bulk emulsion explosives loading system up to now. Authors also analyzed the blasting results and got the following formula $({\Upsilon}= 0.669 + (0.0154{\times}RMR),\;r=0.81)$ from the relationship between a optimum specific charging weight of bulk exp. and rock mass rating. A range of resonable charging weight with a drilling depth is calculated considering a rock conditions.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.560-565
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• 1998

The purpose of this study was to investigate any differences in the efficiency of various antioxidants for the three types of substrates such as corn oil in water (O/W) emulsion, water in com oil (W/O) emulsion, and bulky corn oil. ${\alpha}$-Tocopherol (${\alpha}$-Toc) at 0.01 or 0.02%, ascorbic acid (AsA), ascorbyl palmitate (AP), and BHT at 0.02% were added separately to the prepared O/W emulsion, W/O emulsion, and bulk oil, and their antioxidative effects were compared. The mixture of ${\alpha}$-Toc ind AsA or AP at the level of 0.02% also was tested to observe any synergistic effect. Oxidation was made by storing at 42${\pm}$1$^{\circ}C$ for 25 days and the oxidative stability was determined by peroxide value and conjugated dienoic acid with time fluctuation of storage. The results were as follows: 1. In case of O/W emulsion, the order of antioxidative effect was AP> ${\alpha}$-Toc+AP>${\alpha}$-Toc+AsA>AsA>BHT. 2. In case of W/O emulsion, the order of antioxidative effect was AsA>AP>${\alpha}$-Toc+AsA>BHT. ${\alpha}$-Toc+AP mixture showed the prooxidant effect rather than synergistic effect. 3. In case of bulk oil, the order of antioxidative effect was AsA>AP>${\alpha}$-Toc+AsA>${\alpha}$-Toc+AP\ulcornerBHT. Therefore, AsA, a hydrophilic antioxidant, was more effective in W/O emulsion system than in O/W emulsion system, while the opposite trend was found in AP, a lipophilic antioxidant. AsA, a hydrophilic antioxidant, was more efficient in bulk oil of anhydrous substrate. ${\alpha}$-Toc showed prooxidant effects in all substrates.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.13-16
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• 2003

Vinyl acetate monomer can be polymerized through bulk, solution, emulsion, and suspension polymerization processes. However, in the preparation of PVA from bulk or solution polymerization, there are several technical limitations for obtaining high yield and high molecular weight simultaneously. Thus, the improvement of polymerization method is necessary to prepare the PVA with high yield and high molecular weight because that the difficulty in control of high viscosity and in removal of the heat of polymerization, which might lead to side reactions like branching. (omitted)

• Explosives and Blasting
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• v.18 no.3
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• pp.29-40
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• 2000

Emulan은 ANFO와 bulk Emulsion(Emulite)의 흔합물로서 ANFO입자 사이의 공간은 내수성을 가진 Emulite로 채워지기 때문에 에너지와 밀도가 확실하게 증가하며 뛰어난 내수성을 가진다. 따라서 높은 장전밀도와 고 함유 에너지로 인하여 ANFO 대비 천공 미터당 암석 파쇄량을 40 %이상 증가시킬 수 있으며 저항선과 공간격을 각각 20%이상 증가시킬 수 있다. 특히, 습윤상태가 심한 장소에서 ANFO를 대신하여 가장 경제적인 폭약임이 확인되었다. 본 연구에서는 최신 Bulk-type의 폭약(Emulan)과 AFPO 및 Emulsion계 폭약을 각각 사용하여 현장의 적용성, 상호 발파효과 및 효율성과 경제성 비교를 통하여 앞으로의 대규모 노천현장이나 석산에서 보다 적절하게 사용할 수 있는 화약류에 대하여 알아보고자 하였다.