• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2005.11a
• /
• pp.5-8
• /
• 2005

In this report the developing trends of several clean and green propellants have been summarized. A low-acid clean propellant has been developed, which substantially reduced the content of hydrochloric acid(HCl) in the solid rocket exhaust. Although the chlorine-free approach is now preferred, this technology has not been proved yet. Another acid suppression effect of Magnalium(Mg-Al Alloy) was investigated. Reports says that the concentration of HCl could be reduced to approximately one-fifth of conventional propellant. Many 'green' propellants with low toxicity are being developed for next-generation post-boost propulsion systems, in which combustion research on the Al or Mg fine metal particles with hot steam in various stoichiometric conditions are being performed.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.47 no.5
• /
• pp.335-343
• /
• 2019

The third stage of the KSLV-II is equipped with the reaction control system that performs three axis-control during non-thrust coasting phase and performs a roll axis control during thrust phase. Toxic propellants such as hydrazine have been used for conventional rocket propulsions, however, recently, more studies have been conducted on the use of non-toxic eco-friendly propellants such as ADN and HAN. Especially, hydrogen peroxide has received a growing focus as an emerging propellant. It is considered an alternative of the toxic propellants because of economic advantage in producing the system, conducting operation test, and evaluation of the test result. In this paper, we describes the design, prototype, testing and evaluation of the test results with the 50 N-level hydrogen peroxide monopropellant thruster system which is currently under development.

• Monthly Duck's Village
• /
• s.70
• /
• pp.37-41
• /
• 2009

충청북도가 AI청정지역을 유지한 비결은 한발 앞선 적극적인 방역행정 추진이 가장 큰 원인으로 작용했다. 200년과 2002년 구제역, 2003년 AI 발생을 극복한 경험으로 실용적인 방역시스템 훈련을 강화하는 한편, 2004년 이후 청정지역을 달성할 수 있었던 것은 꾸준하게 친환경축산물 생산기반 구축을 위해 무항생제 면역증강 물질 및 가공장 지원(90억원)과 친환경축산 시설장비 지원(111억원), 생균제 및 가축분뇨자원화 사업(200억원) 지원과 양축농가와 행저이관이 함께 유기적인 협조체제를 유지하면서 사전 방역활동을 한 결과다.

• 동물약계
• /
• no.79
• /
• pp.3-4
• /
• 2001

[ $\cdot$ ]국립수의과학검역원 보유 산업재산권 이용 $\cdot$농림부, '전국 일제소독의 날' 홍보 요청 $\cdot$가축방역사업용 예방약품 품목 및 단가 조사 $\cdot$동물약사감시 행정처분 결과 홍보 $\cdot$협회 제4차 이사회 개최 $\cdot$사료첨가용 동물약품 허가요건 완화 건의 $\cdot$동물약사 관련 회원사 직원교육 실시 $\cdot$돼지콜레라 청정화 추진 공청회 참석 $\cdot$한국 구제역 청정국 지위 조기 회복 $\cdot$제2회 KAHPA컵 골프대회 개최 $\cdot$염산 옥시테트라싸이클린 공급 오퍼상 선정

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.37 no.7
• /
• pp.717-728
• /
• 2009

In the field of rocket propulsion system hydrogen peroxide has been used as mono-propellant and as the oxidizer of bi-propellants. At the beginning, hydrogen peroxide was used as mono-propellant for thrusters, but later it had been replaced by hydrazine, which has better specific impulse and storability. On the other hand, to drive turbo-pumps, hydrogen peroxide is still being utilized. As the oxidizer of bi-propellants it was used until 1970's and from 1990's hydrogen peroxide once again got back to developer's interest, because one of the recent development purposes of rocket propulsion system is low-cost and ecologically-clean. Until now the storability of hydrogen peroxide has been remarkably improved. The combination of Kerosene/$H_2O_2$ also shows similar accelerating performance to Kerosene/$LO_x$ combination because of higher propellant density and higher O/F ratio, even though the propulsion performance is not as good as the combination of Kerosene/$LO_x$. Moreover, its combustion products are much cleaner than Kerosene/$LO_x$ combination.

• Clean Technology
• /
• v.26 no.3
• /
• pp.196-203
• /
• 2020

In this study, a Cu/hexaaluminate catalyst was prepared by a co-precipitation method, and then a binder was added to form a pellet. A catalyst in which Ni and Ru promoters were added to a Cu/hexaaluminate pellet catalyst was prepared. This study focused on examining the effect of the addition of Ni and Ru promoters on the properties of Cu/hexaaluminate catalysts and the decomposition reaction of ADN-based liquid monopropellants. Cu/hexaaluminate catalysts had few micropores and well-developed mesopores. When Ru was added as a promoter to the Cu/hexaaluminate pellet catalyst, the pore volume and pore size increased significantly. In the thermal decomposition reaction of ADN-based liquid monopropellant, the decomposition onset temperature was 170.2 ℃. Meanwhile, the decomposition onset temperature was significantly reduced to 93.5 ℃ when the Cu/hexaaluminate pellet catalyst was employed. When 1% or 3% of Ru were added as a promoter, the decomposition onset temperatures of ADN-based liquid monopropellant were lowered to 91.0 ℃ and 83.3 ℃, respectively. This means that the Ru promoter is effective in lowering the decomposition onset temperature of the ADN-based liquid monopropellant because the Ru metal has excellent activity in the decomposition reaction of ADN-based liquid monopropellant, simultaneously contributing to the increase of the pore volume and pore size. After the thermal treatment at 1,200 ℃ and decomposition of ADN-based liquid monopropellant were repeatedly performed, it was confirmed that the addition of Ru could enhance the heat resistance of the Cu/hexaaluminate pellet catalyst.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2009.11a
• /
• pp.309-312
• /
• 2009

The various hazards should be eliminated before operations for the successful launches or tests. Using the contaminated propellants is one of the causes for the launch and test failures. Especially, the systems using liquid oxygen as an oxidizer have risks about fires and explosions not be forecasted if they are contaminated by oil, water and mechanical impurities. The procedure for the quality control of the liquid oxygen and the liquid oxygen filling system and the lessons learned from the first launch preparation with the system are introduced on this paper.

• Tribology and Lubricants
• /
• v.7 no.2
• /
• pp.13-21
• /
• 1991

선박은 사람이나 화물을 수상(水上) 운송수단의 목적으로 오랜 옛날부터 사용하여 왔으며, 금세기에 이르러서는 오랜 옛날부터 사용하여 왔으며, 금세기에 이르러서는 인류문화의 급속한 발전에 따라 주변생활이 가속화(Speed화), 합리화되어 문명의 혜택을 보다 많이 누리게 된 반면에, 국제간에 파생되는 여러가지 교환현상을 바탕으로 지구는 하나의 촌(村)으로 되어 유통경제를 지배하고 이용하는 운송수단으로 발전되어 왔다. 물질문명이 급속히 발전하는 작금, 선용추진 주 기관의 동향을 살펴보면, 1981년 세계에서 건조한 2000톤급 이상의 선박은 940여척으로 이중 13척이 증기 Turbine. 추진(推進), 나머지는 미끄럼 저속 디이젤 또는 중고속 디이젤 추진으로 되어있다. 이와 병행하여 선박에 쓰여지고 있는 각종 윤활제는 주기관으로서 디이젤 engine, Trubine engine, 가솔린 engine, 석유, engine, 선외기, 왕복동 증기기관, Journal계열로서 역전기, 추력베어링, 중간 베어링, 프로펠러베어링, 일반상선으 보조기계로서 발전기, 공기압축기, Boiler, 각종 Pump, 각종 Motor, 냉동기, 조타장치, Side Thrust, 갑판기계, 환기용 송풍기 및 통풍통, Oil 청정기, 수밀로(水蜜爐), 소화설비, 주기 개방용 천정 크레인, elevator, 어선으로서의 주 기관, 보조기기 등에 쓰여지고 있으며 이밖에 수중날개선 등에도 적용되는 등 실로 다양다종한 윤활제가 요구되고 있음에, 본 논고에서는 제목 건을 중심으로 한 선박과 윤활의 중요 Point만을 간추려 기술하고져 한다.

• Clean Technology
• /
• v.13 no.4
• /
• pp.274-280
• /
• 2007

A liquid-liquid solvent extraction process was developed in this study to recover Fe and Ni from heavily concentrated aqueous ferric chloride solution, in an effort to substitute the conventional iron reduction method. Solvent composition and extraction conditions were first developed from the laboratory experiments, and the pilot system was designed and built for commercialization. Stage numbers for extraction and stripping were determined from pilot plant runs, and other operation data were obtained for mass production.

• Clean Technology
• /
• v.27 no.3
• /
• pp.247-254
• /
• 2021

In this study, an eco-friendly combustion process of waste 2,4,6-trinitrotoluene (TNT: 2,4,6-trinitrotoluene) was developed, and fundamental data for the quantity of the organic matter in the final combustion residues is presented. Because complete combustion of TNT is not possible theoretically, the combustion process was optimized to reduce organic matter content in the combustion residue by performing measures such as heating time changes, addition of propellant material, and after treatment using a high-temp electrical furnace. From the results, it was confirmed that the organic matter content in the residue could be decreased to 7 ~ 10% with each method. The quantity of the organic matter could be minimized by optimizing the combustion conditions of the process. With only a combustion time increase, the amount of organic matter in the combustion residues was measured at about 9 wt%. The environmental friendliness of the final exhaust gas was also confirmed by real time gas component analyses. In addition, the organic contents could be reduced by a further 2 wt% by applying an additional heat treatment using an external electric furnace after the first incineration treatment. In the combustion process of propellant added waste TNT, it was found that various TNT wastes could be treated using the same eco-friendly protocols because the organic content in the residue decreased in accordance with the amount of propellant. The amount of the organic matter content produced by all these methods fulfilled the requirements under the Waste Management Act.