Study on Spatial Distribution of UVA Radiant Intensity for Ballast Water Treatment

2014 ◽  
Vol 644-650 ◽  
pp. 5216-5219
Author(s):  
Man Xia Zhang ◽  
Cheng Yu Yuan ◽  
Lei Shi ◽  
Wen Shi ◽  
Yi Min Zhu
Keyword(s):  
Experimental Data ◽  
Spatial Distribution ◽  
Water Treatment ◽  
Radiant Intensity ◽  
Photo Catalysis ◽  
Exciting Wavelength ◽  
Ballast Water Treatment ◽  
Radiation Conditions ◽  
Uva Radiation ◽  
Transmission Ability

UVA is seldom applied in UV inactivation or disinfection, however, it may be more suitable for underwater photo-catalysis treatment. Since the wavelength of UVA is longer than UVC, the former has higher transmission ability and encounter less disturbance of suspending substances in water. Also, the exciting wavelength of UVA is between 365nm and 413nm which coincides with the wavelength of UVA. Hence, the spatial distribution of UVA radiation is studied for a 15W UVA lamp. The decaying tendencies of UVA radiation intensity were probed over horizontal and vertical distance, behind large amounts of experimental data. Optimal radiation conditions plan to be detected based on the research to guide the UVA treatment.

Underwater Spatial Distribution of UVC Radiant Intensity in Different Water Environment for Ballast Water Treatment

2013 ◽  
Vol 448-453 ◽  
pp. 630-633
Author(s):  
Man Xia Zhang ◽  
Ya Long Liu ◽  
Cheng Yu Yuan ◽  
Yi Min Zhu
Keyword(s):  
Spatial Distribution ◽  
Water Treatment ◽  
Uv Radiation ◽  
Ballast Water ◽  
Tap Water ◽  
Water Environment ◽  
Radiant Intensity ◽  
Bacteria Inactivation ◽  
Ballast Water Treatment ◽  
Influence Of Water

UV radiation, as an effective method for bacteria inactivation, has been applied popularly on ballast water treatment. However, the inactivation efficiencies of UV radiation greatly depend on the UV intensity which distributed unevenly in water and can be deeply affected by the suspending particles in water. For better understanding of the spatial distribution of UV radiation, a 16W UVC lamp was measured underwater to detect the radiant intensity over horizontal and vertical distance. The distribution tendency of UV radiant intensity was probed behind large amounts of experimental data. In addition, four types of different water including tap water, clean seawater, seawater mixed with suspending substances (SS), and seawater mixed with typical algae, were studied to identity the influence of water environment on UV transmission. The impacting significances were compared among different water quality, to optimize the ballast water treatment methods combining with UV radiation.

Considerations in the Design of the Primary Treatment for Ballast Systems

2003 ◽  
Vol 40 (01) ◽  
pp. 49-60
Author(s):  
Michael G. Parsons
Keyword(s):  
Water Treatment ◽  
Great Lakes ◽  
Ballast Water ◽  
Primary Treatment ◽  
Coast Guard ◽  
Secondary Treatment ◽  
Bulk Carrier ◽  
Ballast Water Treatment ◽  
Mechanical Separation ◽  
Hierarchy Process

Investigations are currently underway to establish effective primary and secondary ballast water treatment methods to minimize the potential for the introduction of additional nonindigenous aquatic species into the Great Lakes and other U.S. coastal waters. This treatment could be used in place of mid-ocean ballast exchange currently required by the U.S. Coast Guard for all vessels entering the Great Lakes in ballast from beyond the Exclusive Economic Zone (EEZ). Primary and secondary treatment could provide environmental protection for both Ballast On Board (BOB) vessels, which are required to perform mid-ocean ballast exchange before entering the Great Lakes, and No Ballast On Board (NOBOB) vessels, which are currently exempt from any ballast exchange requirements. Primary treatment using some form of mechanical separation to 100 urn or 50 um followed by secondary treatment using 254 nm UV irradiation or some form of chemical treatment are currently leading candidates. Over the past six years, the Great Lakes Ballast Technology Demonstration Project (GLBTDP) has undertaken the full-scale evaluation of 340 m3/h (1500 U.S. gpm) ballast water mechanical separation using an automatic backwashing screen filter, hydrocyclone, and automatic backwashing disk filter. This experience provides the basis for the investigation of various ballast system design issues that must be considered in the selection and design of the primary ballast water treatment. This investigation is based upon the ballast system of a typical Seaway size bulk carrier using port and starboard 2000 m3/h (8800 U.S. gpm) main ballast pumps. A discrete multicriterion optimization tradeoff study using the Analytical Hierarchy Process (AHP) is also presented to illustrate a rational method for determining the best choice for primary ballast water treatment for such a Seaway size bulk carrier.

Spatial Distribution of Radiant Intensity from Primary Sources for Atomic Absorption Spectrometry. Part I: Hollow Cathode Lamps

1995 ◽  
Vol 49 (4) ◽  
pp. 413-424 ◽  
Author(s):  
Albert Kh. Gilmutdinov ◽  
Bernard Radziuk ◽  
Michael Sperling ◽  
Bernhard Welz ◽  
Konstantin Yu. Nagulin
Keyword(s):  
Spatial Distribution ◽  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Intensity Distribution ◽  
Hollow Cathode ◽  
Imaging System ◽  
Absorption Spectrometry ◽  
Operating Conditions ◽  
Radiant Intensity ◽  
Warm Up

The spatial distribution of radiant intensity from hollow cathode lamps used as radiation sources in atomic absorption spectrometry is investigated with a digital photodiode array imaging system. Intensity distribution over the cross section of each lamp is measured for both atomic and ionic lines of the analyte and the filler gas. The shape of the distribution is strongly dependent on the hollow cathode diameter. In small cathodes the distribution has the shape of a paraboloid with maximum intensity at the hollow cathode axis for all of the recorded lines. The intensity distributions of lines emitted from large cathodes are nonparaboloid and in some cases have a minimum at the cathode axis and a maximum concentric to the cathode walls. It is shown that the intensity distribution for a given lamp has practically the same shape for all currents applied. Data on the evolution of the intensity distribution during warm-up of the lamps and under various operating conditions are presented.

Equipment and Technology Research of Ballast Water Treatments

2014 ◽  
Vol 998-999 ◽  
pp. 414-417
Author(s):  
Jun Wang
Keyword(s):  
Water Treatment ◽  
Chemical Treatment ◽  
Ballast Water ◽  
Comprehensive Treatment ◽  
Technology Research ◽  
Advantages And Disadvantages ◽  
Marine Environmental Protection ◽  
Ballast Water Treatment ◽  
Water Treatments ◽  
Marine Environmental

Biological invasions caused by Ballast water is always one of the diffcult problems of marine environmental protection, and the technology of ballast water treatment is an effective way to solve biological invasion. This article introduce many equipments of ballast water treatment, introduce physical ballast water treatment, chemical treatment and comprehensive treatment, then describes the advantages and disadvantages of these metheods.

scholarly journals ATP assay for rapid onboard testing to detect living microorganisms in Ballast Water

2017 ◽  
Author(s):  
Seungshic Yum ◽  
Bong Gil Hyun ◽  
Kitae Rhie ◽  
Kyoungsoon Shin
Keyword(s):  
Water Management ◽  
Water Treatment ◽  
Cell Volume ◽  
Ballast Water ◽  
Treatment System ◽  
Diatom Species ◽  
Water Treatment System ◽  
Atp Assay ◽  
Ballast Water Treatment ◽  
Ballast Water Management

Rapid and simple analytical methods for viable microorganism detection in ballast water are required to evaluate the efficiency of ballast water treatment system. During the course of systematic investigation of the cytotoxicity and apoptosis assays, it was found that the adenosine triphosphate (ATP) and luminescence based cell viability assay, in other word, an ATP assay was the most sensitive and applicable to ballast water management (BWM). The assay was applied to cultured microalgae samples, and it could detect the existence of 5 viable cells in 100 μl. Comparably low luminescent values were detected in two cultured diatom species than in cultured dinoflagellates. This result might be caused by the small cell volume in diatom species. Following a regression model between ATP concentration and cell volume, an ATP guideline (876 – 109246 relative luminescence units: RLU) was developed for the evaluation of treated ballast water. ATP assay was also applied to the evaluation of ballast water treatment system (BWTS). The luminescence value which obtained from the ATP assay also showed a good correlation with the presence of living natural plankton cells with comparably low luminescence values than the cultured species. The low ATP concentration in natural plankton cells may reflect a decline in their biological activity because of extended exposure to dark conditions. ATP assay could be a suitable method for the monitoring of ballast water management compliance even though the results of this study need further validation.

scholarly journals Lessons Learned in Ballast Water Treatment Equipment Retrofit and Commissioning

2017 ◽  
Author(s):  
Robin Fearnley
Keyword(s):  
Water Treatment ◽  
Ballast Water ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Lessons Learned ◽  
International Maritime Organization ◽  
International Convention ◽  
Ballast Water Treatment ◽  
Treatment Equipment ◽  
Control And Management

Ratification of the International Maritime Organization (IMO) International Convention for the Control and Management of Ships' Ballast Water and Sediments (BWMC)[i] has now forced the hand of operators and ship owners to comply with the BWM, and without a great deal of time to react. The need to integrate and operate Ballast Water Treatment (BWT) Systems on In-Service ships, however, is not new, and BMT have recent and relevant experience in end-to-end BWT system solutions. In 2011 BMT Defence Services Ltd (BMT) produced the installation specification to enable A and P Falmouth Ltd (A and P) to carry out a ballast water treatment plant retrofit installation on the RFA Bay Class ships (i.e. RFA MOUNTS BAY, LARGS BAY and CARDIGAN BAY), enabling the ship to be approved and operated in compliance with the BWMC. In addition, BMT produced documentation to enable A and P to arrange, manage and perform the necessary test, trials and commissioning to prove the equipment installation and that it can be operated in accordance with the requirements of the BWMC. The objective of this paper is to take the reader through the process of design and embodiment of a BWT system retrofit on a relatively complex (with respect to the ballast system) ship. The Bay Class ships are Landing Ship Dock (Auxiliary) ships with separate forward and aft ballast systems (to allow the ships to function in their amphibious roles by way of their stern dock), and a ship wide Ballast Stripping system. Key design and engineering considerations are discussed below and recommendations for the installation of a ballast water treatment system are also offered. International Convention for the Control and Management of Ships' Ballast Water and Sediments, International Maritime Organization, Adoption: 13 February 2004; Entry into force: 8 September 2017.

scholarly journals Features of the Surface and Subsurface Waves Application for Ultrasonic Evaluation of Physicomechanical Properties of Solids. Part 2. Strenghtned Inhomogeneous Surface Layer

2019 ◽  
Vol 10 (1) ◽  
pp. 69-79
Author(s):  
A. R. Baev ◽  
A. L Mayorov ◽  
N. V. Levkovich ◽  
M. V. Asadchaya
Keyword(s):  
Experimental Data ◽  
Surface Layer ◽  
Spatial Distribution ◽  
Surface Wave ◽  
High Frequency ◽  
Hardened Layer ◽  
Gray Iron ◽  
Physicomechanical Properties ◽  
Inhomogeneous Surface ◽  
Ultrasonic Evaluation

The propagation of a pulsed signal of a surface wave over an object with a non-uniform surface layer, obtained, for example, as a result of surface hardening, with structural damage, is accompanied by the dispersion of the velocity of the wave carrying important information about the parameters of such a layer. The aim of the work is to study the relationship between the acoustic parameters of a pulsed acoustic signal of a surface and subsurface waves and the surface layer of steel specimens hardened by high-frequency hardening, and gray iron-chill. Features of the surface and subsurface waves application for ultrasonic evaluation of physicomechanical properties of solids. Strenghtned inhomogeneous surface layer.A brief analysis of the known works on determining the depth of hardened surface layers by various methods, including high-frequency hardening, cementation, etc., is carried out. Based on the Oulder integral expression. The dependence connecting the wave velocity, its frequency, the depth of the hardened layer and the spatial distribution of hardness represented as a step with a changing slope of its side surface simulating the transition zone of the hardened layer are calculated.Using the pulse method and low-aperture transducers with a frequency of 1−3.8 MHz, the dependences of the surface wave velocity on the cutting height of a layer hardened by HDTV hardening are obtained. A comparison of experimental data and calculations of the theoretical model showed a good qualitative correspondence between them, demonstrate a high «sensitivity» of the method in relation to the nature of the change in hardness over the depth of the hardened layer. It is shown that the proposed approach is promising for solving the inverse problem of restoring the spatial distribution of hardness based on experimental data.The goniometric method was approbated to determine the dependence between amplitude-angle characteristics and depth of the surface steel layers hardened by high-frequency hardening and depth of hardened gray iron specimens layer – with chill. It is shown that the optimal angle corresponding maximum of excited surface wave amplitude in steel specimens is decreasing up to 24–26'vs. hardened depth layer. But when the tested specimens from cast iron this angle decreasing is nearly of 6°. Recommendations on the use of research results in practice are given.

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