Ozone is the principal active substances and usually employed in ballast water management systems. In the present study, the corrosion protective effect of ozone was conducted by immersion test and electrochemical tec...Ozone is the principal active substances and usually employed in ballast water management systems. In the present study, the corrosion protective effect of ozone was conducted by immersion test and electrochemical techniques. It was found that corrosion protective effect was revealed in the range of 2.0 to 2.7 ppm of ozone concentration in seawater. The ratio of the rust area of specimen became 20% in that concentration region. The rusted area is strongly influenced by the ozone concentration and the flow rate determined by FEM (finite element method). Ozone has a good influence for ballast tanks, i.e., ozone can delay the rust of ballast tanks, provided that the suitable concentration of ozone is selected. In this case, ozone may stop the corrosion at the defects, if a part of the paint in ballast tank is peeled off. However, ozone may also promote the corrosion of steel when the ozone concentration is very high, e.g., 10 ppm. Attention should be paid to the ozone concentration, if we use ozone as an active substance for ballast water management systems.展开更多
It was originally planned that the Liuhua 11-1 Tension Leg Platform(TLP) would be constructed by China Offshore Oil Engineering Co., Ltd. at its dock in Qingdao. After the closure of upper blocks and the completed con...It was originally planned that the Liuhua 11-1 Tension Leg Platform(TLP) would be constructed by China Offshore Oil Engineering Co., Ltd. at its dock in Qingdao. After the closure of upper blocks and the completed construction of a lower floating body, it would then be towed out of the dock and set for sail via wet towing. However, due to the insufficient depths of the dock in Qingdao and the fairway, additional temporary buoyancy is required for the safe undocking and sailing of the TLP. In this paper, a technique to provide additional buoyancy by use of temporary ballast tanks positioned on both sides outside the Pontoon of the TLP to reduce its draft was studied. The paper also introduced the design, mounting and offshore removal of the temporary ballast tanks and additional related techniques, which will provide reference for subsequent integral undocking projects relating to floating platforms that require additional temporary buoyancy.展开更多
随着国际社会对保护海洋环境要求的不断提升,越来越多的港口和特定水域禁止船舶排放生活污水和灰水,这种禁排规定超出了国际海事组织(international maritime organization,IMO)的《国际防止船舶造成污染公约》(international conventio...随着国际社会对保护海洋环境要求的不断提升,越来越多的港口和特定水域禁止船舶排放生活污水和灰水,这种禁排规定超出了国际海事组织(international maritime organization,IMO)的《国际防止船舶造成污染公约》(international convention for the prevention of pollution from ships,MARPOL)中关于船舶生活污水和灰水的排放要求,使船舶不得不寻求其他舱室用于临时储存不允许排放的生活污水和灰水。该文针对目前船舶在营运过程中将生活污水和灰水临时储存在压载舱内的做法,分别通过对IMO压载水公约关于船舶压载水D-2标准排放要求,以及IMO MARPOL关于船舶生活污水和船舶灰水排放要求的解析,探讨了在压载舱内储存生活污水和灰水的可行性,同时结合IMO关于该问题的讨论进展,提出了在压载舱内临时储存灰水和经处理的生活污水需进一步考虑的技术和操作因素,以规避该行为可能带来的违规风险。展开更多
文摘Ozone is the principal active substances and usually employed in ballast water management systems. In the present study, the corrosion protective effect of ozone was conducted by immersion test and electrochemical techniques. It was found that corrosion protective effect was revealed in the range of 2.0 to 2.7 ppm of ozone concentration in seawater. The ratio of the rust area of specimen became 20% in that concentration region. The rusted area is strongly influenced by the ozone concentration and the flow rate determined by FEM (finite element method). Ozone has a good influence for ballast tanks, i.e., ozone can delay the rust of ballast tanks, provided that the suitable concentration of ozone is selected. In this case, ozone may stop the corrosion at the defects, if a part of the paint in ballast tank is peeled off. However, ozone may also promote the corrosion of steel when the ozone concentration is very high, e.g., 10 ppm. Attention should be paid to the ozone concentration, if we use ozone as an active substance for ballast water management systems.
文摘It was originally planned that the Liuhua 11-1 Tension Leg Platform(TLP) would be constructed by China Offshore Oil Engineering Co., Ltd. at its dock in Qingdao. After the closure of upper blocks and the completed construction of a lower floating body, it would then be towed out of the dock and set for sail via wet towing. However, due to the insufficient depths of the dock in Qingdao and the fairway, additional temporary buoyancy is required for the safe undocking and sailing of the TLP. In this paper, a technique to provide additional buoyancy by use of temporary ballast tanks positioned on both sides outside the Pontoon of the TLP to reduce its draft was studied. The paper also introduced the design, mounting and offshore removal of the temporary ballast tanks and additional related techniques, which will provide reference for subsequent integral undocking projects relating to floating platforms that require additional temporary buoyancy.
文摘随着国际社会对保护海洋环境要求的不断提升,越来越多的港口和特定水域禁止船舶排放生活污水和灰水,这种禁排规定超出了国际海事组织(international maritime organization,IMO)的《国际防止船舶造成污染公约》(international convention for the prevention of pollution from ships,MARPOL)中关于船舶生活污水和灰水的排放要求,使船舶不得不寻求其他舱室用于临时储存不允许排放的生活污水和灰水。该文针对目前船舶在营运过程中将生活污水和灰水临时储存在压载舱内的做法,分别通过对IMO压载水公约关于船舶压载水D-2标准排放要求,以及IMO MARPOL关于船舶生活污水和船舶灰水排放要求的解析,探讨了在压载舱内储存生活污水和灰水的可行性,同时结合IMO关于该问题的讨论进展,提出了在压载舱内临时储存灰水和经处理的生活污水需进一步考虑的技术和操作因素,以规避该行为可能带来的违规风险。