• Journal of Digital Convergence
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• v.10 no.10
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• pp.221-227
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• 2012

In Korea, ocean dumping has been widely used as the ultimate disposal of sewage sludge. However, ocean dumping of food wasted and sewage sludge from 2013 is expected to legally restricted as London convention on marine pollution prevention has been effective in 2009. This research aims to examine the effect of HEAS in treating the environmental pollution load caused by organic high concentrated sludge. Thus, onsite laboratory scale treatability test using HEAS was adopted to treat the high concentrated organic sludge from sewage and industrial wastewater treatment plant. The research results showed that the HEAS is useful to reduce the environmental pollution caused by organic high concentrated sludge. Specific results are as follows. 1. The organic removal after the sludge digestion using the high efficiency aeration system was 55.2-85.8%. Although these results were lower than those from the general sewage treatment, the high efficiency aeration system could be evaluated as efficient, considering the object sludge contained the industrial waster water. 2. The average removal efficiency was about 25.2%. 3. It was revealed that sludge digestion by the high efficiency aeration system could effectively contribute to the sludge treatment cost. Especially, the high efficiency aeration system is more applicable to the onsite treatment of small sewage and wastewater treatment plant that contains high solid content sludge, industrial wastewater sludge, high fixed solid sludge.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.3
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• pp.198-207
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• 1990

Among the biodegradable liquid waste treatment and disposal methods, ocean dumping is a cost-effective and productive manner considering reuse point of view However, when biodegradable liquid waste is dumped in the ocean, oxygen consumption by the decomposition of organic matter must be considered. The purpose of this study is to determine the maximum allowable concentration and dumping rate in the southern waters of the East Sea based on dissolved oxygen level. Streeter and Phelps' model has been used to determine the maximum allowable concentration. Factors in this model, deoxygenation constants and reaeration coefficients, have been determined by appling oxygen consumption method and closed system model. Deoxygenation constants and reaeration coefficients from surface to each standard depth are $0.24\~0.29/day\;and\;0.03\~0.39/day$ in summer, $0.17\~0.20/day\;and\;0.04\~0.56/day$ in winter, respectively. The allowable organic matter concentration($mgBOD/\iota$) to the dissolved oxy-gen sag value of $5mg/{\iota}$ is represented $17.23\times(H)^{-0.37}$ in summer, and $64.96\times(H)^{-0.52}$ in winter by mixing depth(H, m). Csanady's experiment has been applied to estimate the optimum dumping rate. The optimum dumping rate($R,\;m^3/sec$) can be written as a product of the beam(b, m) and the draft(h, m) of vessel, and biochemical oxygen demand of waste($L_n,\;mg/{\iota}$) $R=275{\times}bh^{0.63}L_n^{-1}$ in summer $=745{\times}bh^{0.48}L_n^{-1}$ in winter. The difference of dumping rate between in summer and winter is due to the oxygen distribution.

• Proceedings of the KAIS Fall Conference
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• 2007.05a
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• pp.297-298
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• 2007

본 논문은 가열된 폐식용유를 이용하여 음식물류폐기물에 포함된 수분을 증발시키고 고형성분을 익혀 사료, 퇴비 및 연료화 할 수 있는 장치를 소개한다. $200^{\circ}C$의 폐식용유에서 l분 이내에 완전 건조 처리되며 멸균을 시킬 수 있어 효과적이다. 열원은 소각로 열을 재활용할 경우 경제적이다. 탈리액의 해양투기가 금지될 경우 탈리액을 획기적으로 줄이는 대안이라 여겨진다.

• Environmental engineer
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• s.184
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• pp.64-69
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• 2001

1998년 기준으로 하수처리장에서 발생하는 슬러지는 약 144만톤/년으로 발생량 대부분을 단순매립과 해양투기로 처리하고 있어서, 각종 규제가 강화됨에 따라 처리방안에 대한 대안 마련이 시급한 실정이다. 특히 단순매립 시에는 슬러지 대부분이 유기물로 부패되어 매립지 내에서 악취, 침출수, 해충 등의 2차 환경오염을 야기시키고 있다. 따라서 본 연구개발의 목표는 자가발열 고온호기성 소화(Autothermal Thermophilic Aerobic Digest

• The Korea Swine Journal
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• v.29 no.6 s.334
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• pp.170-174
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• 2007

양돈인들의 가장 큰 고민거리를 이야기한다면 빠지지 않는 대표적인 문제인 분뇨처리. 양돈인 누구에게나 해당하는 걱정거리이다. 2012년부터 해양투기가 금지되는 상황을 감안하면 더욱 그렇다. 하지만 배만용 지부장(만종축산 대표)은 "분뇨 처리 걱정을 왜 하느냐"고 반문한다. 경북 경주지부(배만용 지부장, 59세)는 양돈인들의 숙원사업인 가축분뇨처리 문제해결을 위해 2002년부터 액비사업을 활발히 추진하고 있으며, 이제 그 축적된 노하우를 타 지역 축산농가 및 지방자치단체에 알리는데 선도적인 역할을 담당하고 있는 경북 경주지부를 찾아가 보았다.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.400-402
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• 2007

본 논문은 쓰레기 소각로에서 발생하는 폐열을 활용하여 유기성 폐기물의 재활용하는 방안을 제시한다. 파쇄된 유기성 폐기물을 증류 건조시켜 건조된 고형물과 응축수로 분리하여 응축수는 액비나 탈취제로 활용하고 고형물은 단미사료로 활용하는 완벽한 재활용시스템이다. 탈리액의 해양투기가 금지될 경우 탈리액을 획기적으로 줄이는 대안이라 여겨진다.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.482-482
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• 2010

하수처리장에서 발생하는 유기성 슬러지는 대부분 해양투기에 의해 처분되고 나머지는 매립, 소각, 퇴비화 등으로 처분된다. 그러나 런던협약 '96 의정서' 발효에 의해 2012년부터 해양투기가 금지되고, 매립장 및 소각장의 신규건설은 님비(NIMBY) 현상에 의해 제한받기 때문에 효과적인 슬러지 처분 및 가용화 방법이 요구되고 있다. 현재 초음파[1]나 열처리[2], 오존[3,4], 미생물 처리[5,6] 등 물리, 화학, 생물학적 처리방안이 연구되고 있으나 이러한 방법들은 에너지 과소비, 2차 오염물질 발생에 따른 처리비용 증가 등의 단점을 가지고 있다. 따라서 본 연구에서는 기존의 연구 방법을 보안하고자 전기분해를 활용하여 슬러지 가용화를 시도함으로써 슬러지 발생을 저감시킬 수 있는 방법을 연구하였다. 본 실험에서는 전기분해를 위해 제작된 불용성 전극은 Titanium에 Iridium을 코팅하여 제작하였고, 최대 20V까지 전압을 고정시키고 시간에 따라 변화되는 전류와 전기전도도, pH 값을 관찰하였다. 실험에 사용된 활성슬러지는 3개월간 합성폐수로 순응화 시킨 후에 시료로 사용하였다. 전기분해에 의해 처리된 활성슬러지의 여액을 분석한 결과 SCOD, TN, TP 농도가 각각 510%, 9%, 106% 증가하였다. 이는 전기분해에 의해 미생물의 세포벽이 파괴되어 세포 내 물질들이 세포 외부로 용출되어 미생물들의 이용이 가능한 상태로 되었음을 알 수 있었다. 이는 국내 하 폐수의 낮은 C/N비 때문에 무산소조에 메탄올 같은 외부 탄소원을 공급하는 대신에 별도의 탄소원 공급 없이 가용화 된 슬러지를 반송시킴으로써 슬러지 저감에 따른 폐기 비용과 운전비용의 절감을 기대할 수 있어, 근본적인 슬러지 발생을 저감시킬 수 있는 해결책이라 할 수 있다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.9 no.2
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• pp.97-104
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• 1997

A hyperbolic numerical model with multi-directional waves has been used to investigate harbor tranquility in Pohang New Harbor. Comparing numerical results with field data measured at two stations in the harbor, it was found that use of input condition of multi-directional waves is superior to the use of uni-directional waves. Calculations with unidirectional wave input give errors of about 12% at St. P2 and 26% at St. P3, while calculations with multi-directional wave input give errors of 4 % at St. P2 and. 14% at St. P3. Using the input condition of multi-directional waves, we investigate the tranquility of Pohang New Harbor with two layouts : the condition in 1994 when the downtime at the 7th pier was often reported and the condition in 1996 when the 4th disposal site was constructed. The numerical results show that the problem of downtime at the 7th pier cannot be solved by the construction of the 4th disposal site.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.5
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• pp.515-520
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• 2007

Recently, the treat of sludge is usually progressed by ocean disposal. But it will be totally banned by content of its heavy metal according to London Dumping Convention, gradually. The stable way of treat of sewage sludge should be examined urgently. To solve the problem, recently, there are efficient and environment-oriented method. One of them is to produce absorbent through the activation. This study produces absorbent through steam activation. As basic experiment, optimum activation condition for preparation of good absorbent is researched through study of the fellowing variables : steam flow rate, activated temperature, activation time. As the result of this with standard on iodine adsorptivity, it is chosen, that steam flow rate "30 mL/hr", activation temperature $"500^{\circ}C"$, activation time "60 minutes". At the time, iodine adsorptivity and yield shown that 228.4 mg/g, 77.23%. And also, by using nitrogen adsorption, SEM and EDS are confirmed that pore development, specific surface area, mean pore size, chemical component and content. Pore developed by steam activation is also confirmed that it is micropore.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.4
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• pp.342-348
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• 2015

Recently, many waste is getting into the ocean because of natural disasters and trash of illegality. These destroy the marine ecosystem and the great views around the ocean. Many methods are used for the removal of the waste in the ocean and one of the main waste forms is floating debris. In order to remove the waste, the nets are mostly used and the ships are recently used. However, many problems are occurred due to low number of people and techniques in the ship-based removal. To solve this problem, a surface robot for floating debris removal is developed. To verify the performance of the developed robot, tests of surge, yaw, and floating debris removal are executed. The test results show the possibility of real applications and the need for additional studies.