• Journal of the Korean Society of Marine Environment & Safety
• /
• v.15 no.1
• /
• pp.71-78
• /
• 2009

Korea Marine Environment Management Corporation (KOEM) has waste oil facilities in 13 ports to collect and treat waste oil, bilge, etc. from ships based upon the Marine Environment Management Act of Korea and MARPOL 73/78 convention. Those facilities were designed and have been operated simply to discharge water under the level 15 ppm of oil contents. However, bad smells occurred from rotten organic matters in waste water and direct discharge of harmful substances to receiving water caused civil appeals. Therefore, KOEM tried to develop new process for treatment of oily waste water from ships, which could mitigate harmful substances, save cost, calm down civil appeals and contribute to marine environment preservation. This process consists of 3 steps to remove oil contents via gravity variation at first, $O_3$ input to contact water and organism deposition by inputting condensate deposits. Then finally upper water will be discharged, and the deposited substances in the bottom will be compressed through spinning machine to transfer to the designated contractors for treatment of wastes. This is very effective and innovative in that it could reduce 3 or 4 steps compared with existing process and mitigate not only waste oil concentration but also hard resolving materials such as colloid, ABS, phosphorus, nitrogen and bad smells. This method is expected to minimize bad smells and harmful gases, to save more than 10% of maintenance cost, and to arrange the good base for garbage treatment business dealing with waste water and bad smell.

• Journal of Advanced Marine Engineering and Technology
• /
• v.35 no.5
• /
• pp.582-589
• /
• 2011

The fuel cell technology has been considered as a technology to reduce greenhouse gases emission from a ship. In this research, internal reforming 500kW solid oxide fuel cell system fueled by methane for a ship were developed. Characteristics of gas temperature, stack power and system efficiency depending on the air flow rate, $CH_4$ flow rate, $H_2O$ flow rate, and system operation pressure are evaluated. As a result, air and $CH_4$ flow rate directly affect the temperature of inlet and outlet gas in the fuel cell stack. When the air and $H_2O$ flow rate increase, the stack power and system efficiency increases. However, the case of $CH_4$ flow rate increase, the efficiency decreases.

• Journal of Korean Society of Environmental Engineers
• /
• v.38 no.11
• /
• pp.596-602
• /
• 2016

Potassium iodide (KI) TRO sensor for measuring total residual oxidant which is an index for disinfection and neutralization in ballast water has been constructed. The results of UV absorption wavelength and absorbance test in various TRO concentrations show high linear correlation ($r^2=0.9825$) at 350 nm wavelengths and it can be possible to visualize numerical value of TRO concentration (0.1~7.0 mg/L). The result of comparison test according to TRO concentration between the KI based TRO sensor system and the DPD based TRO sensor system showed identical trend. Overall results indicated that the KI TRO sensing system could be applied for continuous TRO concentration measurement in ballast water treatment system.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.5
• /
• pp.1330-1343
• /
• 2020

In this study, emulsion fuel which contained water of 10 ~ 20% was prepared mixed with water and MDO(Marine Diesel Oil) which largely used in near sea. Diffusion stability of emulsion fuel was measured. Diffusion stability was measured at 30℃, 45℃, and 60℃ for 10 days respectively. The stability of the emulsion fuel was stabilized in the order of MDO-10 > MDO-13 > MDO-16 > MDO-20 and it means that the stability of the emulsion fuel was found to be stable in the order of low water content. Meanwhile, an engine dynamo-meter was used to test whether the manufactured emulsion fuel was actually available in the engine. The emulsified MDO emulsion fuel could be used as fuel for ships. For samples with more than 16% water added emulsion fuel, smoke was reduced by more than 50% in the load area of more than 50%, and nitrogen oxides were reduced by 20%.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.17 no.3
• /
• pp.189-197
• /
• 2014

Collection and management of various information related to the ballast water are the essential components for the efficient implementation of the IMO Ballast Water Management Convention. Based upon the ballast water risk assessment and information system developed by other states, regions or even at global level, an integrated information system has been established to be applied to our domestic ports. The integrated information system is composed of four DataBases (DB) which are the Shipping DB, Ballast water DB, Port Environment DB and Species DB. The Shipping DB has been established based on the data collected from the Port Management Information System (Port-MIS). For the Ballast water DB, Ballast water has only been estimated by the loading/unloading of the cargoes as the convention has not come into effect yet. The Port Environment DB and Species DB are being established based on the reference documents and existing and newly collected monitoring data. From these DB, the integrated information system will be able to provide a base for the information search, statistic analysis and risk assessment of ballast water. Once the convention comes into effect, this integrated information system will be applied to manage the domestic ballast water discharge and also the port management.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.15 no.3
• /
• pp.219-226
• /
• 2012

The International Maritime Organization (IMO) adopted the International Convention for the Control and Management of Ships' Ballast Water and Sediments in 2004 to prevent the transfer of aquatic organisms via ballast water. Thirty-four ballast water treatment systems were granted IMO active substance basic approval, among which twenty systems were granted final approval. This paper is an in-depth consideration of the mechanism principles of the treatment systems that received active substance basic or final approval from IMO, and on the concentration of Total Residual Oxidant (TRO). The TRO maximum allowable discharge concentration was reduced by neutralization equipment, resulting with a concentration lower than 0.2 ppm. However, between various treatment systems TRO maximum allowable dosage showed large differences, ranging from 1 to 15 ppm. The discrepancies of treatment allowable dosage concentration between different treatment systems are largely due to the properties of species and water conditions such as the temperature and turbidity, rather than the characteristics of treatment systems and the type or presence of filters etc.

• Journal of Advanced Marine Engineering and Technology
• /
• v.37 no.8
• /
• pp.822-828
• /
• 2013

Since the operating temperature of Solid Oxide Fuel Cell (SOFC) is high, the heat management of the gases supplied to fuel cell system is important. In this paper, the temperature characteristic of the gases supplied to the anode and the cathode of the fuel cell is studied in case of utilizing the waste heat contained in the ship exhaust gas as a heat source to heat up the fuel, gas and water supplied to a 500kW SOFC system for a ship power. For the fuel cell system proposed in this paper, the temperature of gases supplied to the anode and the cathode was the highest temperature at 963K when the exhaust gas of the fuel cell was utilized as the heat source for gases supplied to fuel cell system instead of utilizing the ship exhaust gas. In addition, the engine power did not effect on the temperature of gases supplied to the fuel cell stack.

• Journal of Navigation and Port Research
• /
• v.41 no.3
• /
• pp.79-86
• /
• 2017

Ballast water filled into and discharged from the ballast tank of a ship has a negative impact on local marine environment due to various aquatic organisms contained therein. The IMO developed and adopted "The International Convention for the Control and Management of Ships Ballast Water and Sediments, 2004" with the purpose of protecting the marine environment from transfer of harmful aquatic organisms in ballast water carried by ships. The IMO BWM Convention was approved in September 2016 and ships must be equipped with ballast water management system after September 2017. Ships' ballast water treatment methods are divided into using active substances as electrolytic type, ozone type, chemical dosing type and using physical treatment type as filter type, ultraviolet type. It is also used with a combination of two methods. Electrolysis is superior in terms of cost and efficiency. In this study, basic principles, components, and land base test contents of electrolysis ballast water treatment system, a direct electrolyzed ballast water treatment system, were examined. Land base test was conducted with 300m3/h capacity device at the KIOST Geoje plant where the government test facility was installed. This test validated that the system meets IMO standards.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.19 no.5
• /
• pp.525-530
• /
• 2013

In this study, the generator engine of training ship M/S "HAE RIM" of Kunsan National University which is being operated for 20 years was used in the experiment. The experiment was carried out under the engine speed of 1200rpm, then the load was varied 30 kW intervals from 0 to 90 kW and the injection timing was varied $2^{\circ}$CA intervals from BTDC $19^{\circ}$ to $23^{\circ}$CA. In the case of advancing fuel injection timing from BTDC $21^{\circ}$CA to $23^{\circ}$CA, specific fuel consumption is decreased by 1.37%, NOx is increased by 11.59 %, soot is decreased by 23.5 % and $SO_2$ is decreased by 2.8 %. Accoring to the analysis of effects of fuel injection timing on combustion & exhaust emissions characteristics on an old marine diesel engine, it is proved that the optimum fuel injection timing is BTDC $23^{\circ}$ which is $2^{\circ}$ faster than that of original injection timing.

• Journal of Advanced Marine Engineering and Technology
• /
• v.35 no.4
• /
• pp.406-413
• /
• 2011

Recently the fuel cell has been spotlighted as a technology to reduce greenhouse gases emission from a ship. In this research, internal reforming 500kW solid oxide fuel cell stacks fueled by methane for a ship were developed. Characteristics of power and efficiency depending on the number of cells in the stack, hydrogen conversion ratio, and active area of the cell are evaluated. Also the effects of air and methane supplying conditions on performance are analyzed. As a result, as the number of cells, hydrogen conversion ratio, active area of the cell, or supplied air flow rate increase, the stack power and efficiency increase. When the methane flow rate increases, the power increases. However the efficiency decreases. In addition, the case at the current of 976.4 A, voltage of 529.1 V, with corresponding power of 516.6 kW shows that the efficiency of fuel cell stack is 42.91%.