Deterioration of Water Ballast Tank Coating Systems by Active Substances in Ballast Water Management Systems

Sodium hypochlorite and ozone are the principal active substances and usually employed in ballast water management systems. In the present study, the authors focus on the effect of these active substances to the maaix polymer of coating. In order to obtain such information, the authors investigated the penetration of active substances to the polymer from cross section of specimens introduced by SAICAS （surface and interracial cutting analysis system）, followed by FT-IR-ATR （Fourier transform infrared and attenuated total reflectance） spectroscopy analysis from Z direction of cross section. The corrosion test of coating panels by these active substances （control as artificial seawater） has been conducted for 120 days. The results show that the depth profile of each active substance is around few dozens of micrometers from coating surface. The criteria of corrosion test cannot be determined by these results due to lacking in actual corrosion data immersed for 15 years under active substances. However, the authors evaluated the effect on ballast tank coating systems by active substances using analytical methods of SAICAS and FT-IR-ATR spectroscopy.

Treating ballast water with hydroxyl radical on introduced organisms

With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl radicals on introduced organisms in ballast water was experimentally investigated. The results indicate that the contents of chlorophyl-a, chlorophyl-b, chlorophyl-c and carotenoid are decreased by 35%-4% within 8.0s and further to the lowest limit of test 5 minutes. In addition, the main reasons of cell death are the lipid peroxidation, the strong destruction to the monose, amylose, protein, DNA and RNA of cell, and damage in CAT, POD and SOD of antioxidant enzyme system.

Optimization of Bow Shape for a Non Ballast Water Ship

In this research,a commercial CFD code ＂Fluent＂ was applied to optimization of bulbous bow shape for a non ballast water ships（NBS）.The ship was developed at the Laboratory of the authors in Osaka Prefecture University,Japan.At first,accuracy of the CFD code was validated by comparing the CFD results with experimental results at towing tank of Osaka Prefecture University.In the optimizing process,the resistances acting on ships in calm water and in regular head waves were defined as the object function.Following features of bulbous bow shapes were considered as design parameters： volume of bulbous bow,height of its volume center,angle of bow bottom,and length of bulbous bow.When referring to the computed results given by the CFD like resistance,pressure and wave pattern made by ships in calm water and in waves,an optimal bow shape for ships was discovered by comparing the results in the series of bow shapes.In the computation on waves,the ship is in fully captured condition because shorter waves,λ/Lpp 0.6,are assumed.

Input characteristics and risk analysis of ballast water from offshore entry ships in China

Large quantities of ballast water discharge from ocean going ships in sea ports of China is one of the important factorswhich cause the spread of aquatic nonindigenous harmful species isolated geographically by waters,the deteriorating environment of the near-shore water area and the frequent outbreaks of red tides.In this paper,the total amount of the ballast water input estimation model for entry ships in Chinese ports was established.The information of foreign trade shipping and the import and export goods released publicly by the State Department of Transportation and the State General Administration of Customs were investigated.And then,the input features and its ecological environment risk of ballast water in China's offshore entry ships from2007to2012were analyzed based on the established total input amounts of ballast water from entry ships to Chinese sea ports together with the ballast water input ratio of the five major port-groups in China.The results show that:the total ballast water input amounts from entry ships of the five major port-groups in China are extremely imbalanced.The most developed Yangtze River Delta in economy has the biggest total ballast water input amounts,103.61million tons in2012.The second is the Circum-Bohai Sea Region(73.66million tons)and the third is the Pearl River Delta(67.24million tons).The total ballast water input amounts of the northwest and the southwest coastal areas are less,only16.57and5.71million tons respectively.The large quantity of entry ships’ballast water discharge has been an enormous threat to ecological environment of our country's sea areas,especially to economically developed regions.

Added Resistance Acting on Hull of a Non Ballast Water Ship

In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, Japan. In the present paper, the performances of three kinds of bow shapes developed for the NBS were theoretically and experimentally investigated to find the best one in high waves. In previous papers, an optimum bow shape for the NBS was developed in calm water and in moderated waves. For a 2 m model for experiments and computations, the wave height is 0.02 m. This means that the wave height is 15% of the draft of the ship in full load conditions. In this paper, added resistances in high waves up to 0.07 m for a 2 m model or 53% of the full load draft are investigated. In such high waves linear wave theories which have been used in the design stage of a ship for a long time may not work well anymore, and experiments are the only effective tool to predict the added resistance in high waves. With the computations for waves, the ship is in a fully captured condition because shorter waves, λ/Lpp<0.6, are assumed.

Development and evaluation of a DNA microarray assay for the simultaneous detection of nine harmful algal species in ship ballast and seaport waters

Rapid,high-throughput and reliable methods are urgently required to accurately detect and monitor harmful algae,which are responsible for algal blooms,such as red and green tides. In this study,we successfully developed a multiplex PCR-based DNA microarray method capable of detecting nine harmful algal species simultaneously,namely A lexandrium tamarense,Gyrodinium instriatum,Heterosigma akashiwo,Karenia mikimotoi,Prorocentrum donghaiense,Prorocentrum minimum,Ulva compressa,Ulva ohnoi and Ulva prolifera. This method achieved a limit of detection(LOD) of 0.5 ng of genomic DNA(orders of magnitude of the deci-nanogram range) in the tested algae cultures. Altogether,230 field samples from ship ballast waters and seaport waters were used to evaluate the DNA microarray. The clinical sensitivity and specificity of the DNA microarray assay in detecting field samples were 96.4% and 90.9%,respectively,relative to conventional morphological methods. This indicated that this high-throughput,automatic,and specific method is well suited for the detection of algae in water samples.

Tests to evaluate the ecological impact of treated ballast water on three Chinese marine species

Ballast water has been a topic of concern for some time because of its potential to introduce invasive species to new habitats. To comply with the International Convention for the Control and Management of Ships' Ballast Water and Sediments, members of the International Maritime Organization(IMO) must equip their ships with on-board treatment systems to eliminate organism release with ballast water. There are many challenges associated with the implementation of this IMO guideline, one of which is the selection of species for testing the ecological impacts of the treated ballast water. In the United States, ballast water toxicity test methods have been defined by the United States Environmental Protection Agency. However, the test methods had not been finalized in China until the toxicity test methods for ballast water were established in 2008. The Chinese methods have been based on species from three trophic levels: Skeletonema costatum, Neomysis awatschensis, and Ctenogobius gymnauchen. All three species live in broad estuarine and open sea areas of China; they are sensitive to reference toxicants and acclimatize easily to different conditions. In this paper, the biological characteristics, test processes and statistical analysis methods are presented for the three species. Results indicate that the methods for evaluating these three organisms can be included in the ecological toxicity tests for treated ballast water in China.

Eradication of algae in ships’ ballast water by electrolyzing

In order to verify the effectiveness of electrolytic treatment on ships’ ballast water, experiments are carried out by a pilot system in laboratory. The raw seawater and seawater with different concentrations of different algae are simulated as ships’ ballast water. The algae in the raw seawater can be killed if it is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L. If the seawater with one kind of algae (Nitzschia closterum, Dicrateria spp., or Pyramidomonnas sp.105cells/mL) is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L, the alga can be sterilized. If the seawater with one kind of algae (Dunaliella sp., Platymonas or Chlorella spp.) is directly treated by electrolyzing with an initial residual chlorine concentration of 4 mg/L, the instant mortality changes with the concentration of different algae. However, after 72 hours, in all treated samples, there are no live algal cells found.

Ballast Water Treatment Methods of International Vessels Docking in Loboc Port, Iloilo City, Philippines

This study delved on the ballast water management methods among international vessels docking at Loboc Port, Iloilo City, Philippines and other factors that are considered during ballast operation. The respondents of this study were the seafarers from the 15 international vessels docking at Loboc Port. The findings of the study revealed that the international vessels docking at Loboc Port used the sequential method, flow-through method, chlorination method, hydrogen peroxide, UV （ultraviolet） irradiation and filtration method in ballasting. In order to prevent transfer of alien invasive species, government authorities such as MARINA （Maritime Industry Authority） and Philippine Coast Guard should strictly monitor and implement the ballast water management methods used by international vessels based on the guidelines set by the IMO （International Maritime Organization）.

Influence of Ozone Injection on Corrosion Behavior of Steel in Water Ballast Tank

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.

The Management of Environment Cost Caused by Ballast Water

According to classical economic theory,external cost is the indirect,and uncompensated,social or environmental cost caused to an uninvolved third party that arises as an effect of another party’s activity.In light of this,the environmental cost caused by ballast water is considered as a negative externality.This paper aims to contribute by proposing that the environmental cost caused by ballast water can be determined through questionnaires,and that the imposition of a Pigouvian retributive tax is required to compensate for the environmental damage caused.The paper proceeds as follows.Firstly,ballast water management is discussed.Second,the environmental cost is discussed and it is asserted that it is important to have clear regulations and to update them frequently to prevent or minimize ballast water’s negative impact on the environment.Finally,it is suggested that the environmental cost caused by ballast water can be determined by questionnaires and,more specifically,by the WTP(Willingness to Pay)method,and that a special Pigouvian corrective taxation which can internalize this cost should be imposed.

Large scale northward expansion of warm water species Skeletonema tropicum (Bacillariophyceae) in China seas

Skeletonema tropicum is regarded as a species with an affinity to warm waters and it has never been reported in seas where temperatures drop below 11℃ in winter. Previous studies in China reported that S. tropicum was restricted to subtropical and warm temperate seas （East and South China Seas）, but the species was recently found during August cruises of 2009 and 2010 in Jiaozhou Bay, Yellow Sea, located several hundred kilometers to the north. Here, winter water temperatures often drop below 5℃. Identification of S. tropicum was confirmed under light and scanning electronic microscopes and maximum cell abundance in Jiaozhou Bay was estimated as 1.73× 10^4 celI/L. This record of S. tropicum in Jiaozhou Bay represents a significant northward expansion in the geographic range of the species. Ship ballast water was identified as a possible carrier of S. tropicum from southern places along Chinese coastline, and in addition, thermal pollution from local power stations and seawater desalination plants may provide suitable conditions for species over-wintering.

A Study on the Composition of Wastewater Produced during Ship Biofouling Management

The IMO(International Maritime Organization)recognized the problem of invasive species invasion and adopted the“International Convention for the Control and Management of Ships’Ballast Water and Sediments”in 2004,which came into force on September 8,2017.In 2011,the IMO approved the“Guidelines for the Control and Management of Ships’Biofouling to Minimize the Transfer of Invasive Aquatic Species”to minimize the movement of invasive species by hull-attached organisms and required ships to manage the organisms attached to their hulls.Invasive species enter new environments through ships’ballast water and hull attachment.However,several obstacles to implementing these guidelines have been identified,including a lack of underwater cleaning equipment,regulations on underwater cleaning activities in ports,and difficulty in accessing crevices in underwater areas.The shipping industry,which is the party responsible for understanding these guidelines,wants to implement them for fuel cost savings resulting from the removal of organisms attached to the hull,but they anticipate significant difficulties in implementing the guidelines due to the obstacles mentioned above.Robots or people remove the organisms attached to the hull underwater,and the resulting wastewater includes various species of organisms and particles of paint and other pollutants.Currently,there is no technology available to sterilize the organisms in the wastewater or stabilize the heavy metals in the paint particles.In this study,we aim to analyse the characteristics of the wastewater generated from the removal of hull-attached organisms and select the optimal treatment technology.The organisms in the wastewater generated from the removal of the attached organisms meet the biological treatment standard(D-2)using the sterilization technology applied in the ships’ballast water treatment system.The heavy metals and other pollutants in the paint particles generated during removal are treated using stabilization technologies such as thermal decomposition.The wastewater generated is treated using a two-step process:(1)development of sterilization technology through pretreatment filtration equipment and electrolytic sterilization treatment and(2)development of technology for removing particle pollutants such as heavy metals and dissolved inorganic substances.Through this study,we will develop a biological removal technology and an environmentally friendly processing system for the waste generated after removal that meets the requirements of the government and the shipping industry and lay the groundwork for future treatment standards.

基于随机森林的船舶压载水系统故障诊断

针对船舶压载水系统工作环境恶劣,相关设备易发生故障且传统人工故障检测方法耗时长、误判率高的问题,提出一种基于随机森林算法的船舶压载水系统故障诊断方法。以某大型集装箱船模拟器压载水系统的5种运行状态的180组运行数据为样本,随机选取150组数据作为训练集,30组数据作为测试集,使用MATLAB软件进行模型搭建。结果表明,模型的总体准确率达到95%以上,可以较为准确地对船舶压载水系统的常见故障进行判别。

基于ISSA-ELM的船舶压载水系统故障诊断研究

为了从船舶压载水系统中有效挖掘数据信息,降低极限学习机(ELM)初始参数随机性对故障诊断精度的影响,提出基于改进麻雀搜索算法(ISSA)优化ELM的船舶压载水系统故障诊断模型。首先,使用自适应加权策略和Levy飞行策略改进发现者位置公式,获得ISSA并验证其性能;而后利用改进后的麻雀搜索算法对ELM的初始输入权重和阈值进行优化,建立基于ISSA-ELM的故障诊断模型。结果表明,ISSA-ELM模型的故障诊断精度为96.6%,比SSAELM、PSO-ELM、GWO-ELM模型高出1.8%、3.5%和2.6%,比ELM和SVM模型高出4.5%和7.1%。

Technical feasibility study of an onshore ballast water treatment system

To fulfill the requirements of Guidelines forapproval of ballast water management system(G8),a setof onshore ballast water treatment equipment utilizingmicro-pore ceramic filtration(MPCF)and UV radiation(MPCF&UV)system was designed and set up with amaximum flow rate of 80 m^(3)·h^(-1).Technical feasibilities ofMPCF&UV system were evaluated in three areas:removalefficiencies of indicator organism and oceanic bacteria,perdurability of a ceramic filter,and application on nativeseawater.The results showed that no indicator organism(Dunaliella)or oceanic bacteria was detected aftertreatment of 20 L MPCF and UV radiation at 1.3×10^(4)μW·s·cm^(-2).A 20 L ceramic filter can run continuouslyfor 5.3 h at the flow rate of 15 m3·h-1 before itspressure drop up to 0.195 MPa.The removal percentage oftotal plankton amounts were 91.9%at a flow rate of70 m^(3)·h^(-1)by 80 L MPCF and UV radiation at 1.3×10^(4)μW·s·cm^(-2).

压载水管理系统关键技术分析

通过解读压载水公约,介绍压载水公约的实施要点,对压载水管理系统实践中的要求及注意事项进行归纳总结。通过对比分析压载水处理技术,介绍技术优劣性,对目前市场上4种主流的压载水管理系统分析其关键技术要点,并结合实践中遇到的问题提出建议。

船舶压载水复合集成化处理系统研究

为提高船舶运营的安全性、可持续性和环保性,文章首先探讨了传统系统面临的微生物入侵、海洋污染、运行压力和系统复杂等问题,明确了这些挑战对生态系统和渔业的负面影响。接着详细介绍了新系统的结构及工作原理,以及系统优化带来的创新性,该新系统设计不仅降低了运营成本,减轻了环境负担,还提高了压载水处理的整体性能,为船舶行业的可持续发展提供了有力支持。

基于三菱Q型PLC的泵房本质安全自控系统研究

泵房用于船舶压载水设备的出厂测试,其本身属于有限空间,内部存有氢气、氯气等危险气体,人员频繁进出存在较大安全隐患。为提升存储海水并模拟海水环境泵房的本质安全,在大量试验分析的基础上,以三菱Q型PLC为控制核心,研究了一套泵房本质安全自控系统,该系统可实现远程控制、实时监测、自我诊断等功能,有效提高了现场作业效率,同时极大消除了频繁进入泵房带来的安全隐患,实现了作业过程的本质安全。

船舶压载水系统仿真建模与控制的研究与实现

以某油轮为母型船,建立了整个船舶压载水系统的仿真数学模型,并利用MINIS通用仿真平台与Intouch工控组态软件,开发了船舶压载水系统动态仿真与监控程序,基于全PC平台实现了船舶进、出港和货油装、卸过程中压载水系统的动态仿真与监控调节。