scholarly journals Ballast Water Treatment Performance Evaluation under Real Changing Conditions

2020 ◽  
Vol 8 (10) ◽  
pp. 817
Author(s):  
Pung-Guk Jang ◽  
Bonggil Hyun ◽  
Kyoungsoon Shin
Keyword(s):  
Ballast Water ◽  
Suspended Solids ◽  
Water Discharge ◽  
Suspended Solid ◽  
Coast Guard ◽  
Small Subset ◽  
High Concentration ◽  
Ballast Tank ◽  
Filter Unit ◽  
Filter Clogging

We conducted a shipboard ballast water test using seawater of extreme turbidity collected from Shanghai Port (China) (>300 mg total suspended solids (TSS)/L), and normal seawater collected in other ports (<100 mg TSS/L). All three types of International Maritime Organization (IMO)-approved ballast water management system (BWMS) tested failed to properly operate because of filter clogging or insufficient generation of oxidants under near-fresh water conditions with extremely high concentration of suspended solid during ballasting. It was also found that the number of microorganisms increased with longer ballast water retention time, with higher numbers in the treated discharge water. The results suggest that when operating a BWMS involving a filter unit in areas with water having high concentrations of suspended solids, the filter unit should be used during ballast water discharge, rather than during ballasting. This method has the advantage of removing ≥50 µm organisms at discharge that could not be removed by a filter during ballasting. For ballast water retained for long storage times, the results suggest the use of BWMSs involving UV units or electrolysis during deballasting. In addition, BWMSs involving electrolysis units provide the opportunity to maintain residual total residual oxidant (TRO) levels, using a partial ballast tank. Although the BWMSs tested are a small subset of the large number of IMO-approved BWMSs, the results demonstrate that there is a significant gap between the technology currently available and capacity to meet IMO and US Coast Guard standards.

scholarly journals Navigating in Uncertain Waters: 2006 Update on the Regulation of Ballast Water Discharge in the United States

2007 ◽  
Vol 1 ◽  
Author(s):  
Julie A. Aquino
Keyword(s):  
United States ◽  
Ballast Water ◽  
Native Species ◽  
Water Discharge ◽  
Federal District ◽  
Marine Species ◽  
The United States ◽  
Coast Guard ◽  
District Court ◽  
Statutory Authority

Every day more than 10,000 marine species are swept up in the ballast water of ships and make their way across the globe. 1 When discharged into non-native waters, these species are able to damage infrastructure, disrupt commerce, out compete native species, reduce biodiversity, and threaten human health.2 The ecological losses are difficult to quantify; however, the direct and indirect economic costs have been measured at billions of dollars per year in the United States alone.3 Recognizing the severity of the problem, Congress directed the Coast Guard in 1996 to administer a ballast water program and issue guidelines.4 According to various interest groups, the aquatic invasive species problem persists today despite Coast Guard involvement because of inherent and technological limitations surrounding ballast water management (BWM).5 However, other groups believe that the crux of the problem is that the Coast Guard has simply not acted aggressively enough to address the problem. In March 2005, an environmental advocacy group, joined by six states, convinced a federal district court for the Northern District of California that the EPA had exceeded its statutory authority by exempting the discharge of ballast water from the control of the Clean Water Act (CWA)6 in the case of Northwest Environmental Advocates v. EPA.

scholarly journals Essential Preparations for compliance and contingency options

2017 ◽  
Author(s):  
Debra DiCanna
Keyword(s):  
Water Management ◽  
Ballast Water ◽  
Water Discharge ◽  
Performance Standards ◽  
Coast Guard ◽  
State Control ◽  
Start Up ◽  
Marine Environmental Protection ◽  
And Performance ◽  
Ballast Water Management

Even though the Ballast Water Management Convention (BWMC) (referred to herewith as the Convention) has been ratified and a few ballast water management systems (BMWS) have received US Coast Guard (USCG) type approval, many shipowners and operators are reticent to begin the significant process of planning for compliance with ballast water discharge and performance standards. This delay is most probably due to the uncertainty in the implementation dates in the BWMC and limited options of USCG type approved BWMS. These delays may result in significant ramifications for shipowners if the process for compliance is not fully evaluated. This process includes selecting, designing installation, purchasing, start-up and commissioning of BWMS. Clarity on the implementation schedule should be determined at the 71st session of the Marine Environmental Protection Committee of the International Maritime Organization (IMO MEPC 71) and allow shipowners to plan for compliance. An important aspect of implementation is developing a strong compliance plan. A central part of compliance is identifying possible problems and contingency options that may alleviate any potential port State control issues. The paper will identify possible problems and contingency measures to ensure ship operations are not impacted. An important issue is that the BWMC does not include provisions for contingency measures. The paper will also outline needed contingency measures to be addressed by the IMO in any amendments to the BWMC.

scholarly journals F-Specific RNA Bacteriophage Transport in Stream Water: Hydro-Meteorological Controls and Association with Suspended Solids

Water ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2250
Author(s):  
Núria Martínez-Carreras ◽  
Leslie Ogorzaly ◽  
Cécile Walczak ◽  
Christophe Merlin ◽  
Emmanuelle Montargès-Pelletier ◽  
...  
Keyword(s):  
Time Scales ◽  
Suspended Solids ◽  
Stream Water ◽  
Water Discharge ◽  
Model Performance ◽  
Suspended Solid ◽  
Driving Factors ◽  
Storm Runoff ◽  
Low Flows ◽  
Runoff Events

F-specific RNA bacteriophages (FRNAPHs) are commonly used as indicators of faecal and viral contamination in waters. Once they enter surface waters, the exact role of suspended solids, sediments and hydro-meteorological factors in their fluvial fate and transport is poorly understood, and long-term studies (e.g., over years) are lacking. In this study, FRNAPH concentrations and genogroup distribution were measured in the Orne River (France) during two years at weekly intervals, and during four storm runoff events. Hydro-meteorological driving factors were investigated at both time scales. FRNAPH concentrations and genogroups at different depths of a riverbank sediment core were also examined to better discriminate the origin of the faecal pollution. During low flows, the FRNAPH and the suspended solid transport were decoupled and the FRNAPH concentrations were mainly correlated with the air and water temperature. During storm runoff events, the FRNAPH concentrations only showed a significant correlation with conductivity, turbidity and water discharge. Despite the uncertainty of the predictions, multi parameter regression models using hydro-meteorological variables were suitable to predict log transformed FRNAPHs’ concentrations at low flows with a standard error of 0.46. Model performance using the storm runoff events dataset was low. This study highlights different driving factors at low flows and during storm runoff events, and the need to measure at both time scales to better understand phage transport dynamics in surface water.

Evaluation of nutrient runoff from the kako river by continuous daily sampling

1996 ◽  
Vol 34 (12) ◽  
pp. 67-72
Author(s):  
Yukio Komai
Keyword(s):  
Suspended Solids ◽  
Water Discharge ◽  
Electronic Conductivity ◽  
High Water ◽  
Nutrient Loads ◽  
Discharge Condition ◽  
Nutrient Runoff ◽  
Average Value ◽  
Daily Sampling ◽  
A Site

A water sample was taken once a day for 15 months at a site near an estuary of the Kako River, Japan, to estimate nutrient loads from rivers to the sea. Total phosphorus (T-P), total nitrogen (T-N), suspended solids (SS) and electronic conductivity (EC) were measured. T-P and SS concentrations varied in proportion to the discharge, and T-P concentrations increased with those of SS, too. EC varied inversely with the discharge, but the fluctuations of T-N concentrations were less than those of T-P and SS concentrations. Water quality remained, for the most part, constant throughout the day. T-P, T-N and SS load were 181t/year, 2320t/year and 51000t/year in 1992, respectively, 54% of T-P load, 47% of T-N load and 80% of SS loads outflowed in those cases where the discharge was more than 100 m3/s, which were 36 days in 1992. 79% of T-P load, 69% of T-N load and 92% of SS load outflowed in periods of high water discharge, which were 88 in 1992. T-P and T-N loads calculated by using one day's data in every month were 151t/year and 2450t/year. But nutrient loads calculated by using the average value of data from an ordinary discharge were two or three times lower than calculated yearly loads. These results showed the importance of estimating the yearly load considering the discharge condition and sampling at a time of high water discharge.

Ecosystem under pressure: Ballast water discharge into Galveston Bay, Texas (USA) from 2005 to 2010

2012 ◽  
Vol 64 (4) ◽  
pp. 779-789 ◽  
Author(s):  
Jamie L. Steichen ◽  
Rachel Windham ◽  
Robin Brinkmeyer ◽  
Antonietta Quigg
Keyword(s):  
Ballast Water ◽  
Water Discharge ◽  
Galveston Bay

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.

A generalized settling approach in the numerical modeling of sedimentation tanks

1998 ◽  
Vol 38 (3) ◽  
pp. 95-102 ◽  
Author(s):  
G. Mazzolani ◽  
F. Pirozzi ◽  
G. d'Antonoi
Keyword(s):  
Transport Model ◽  
Numerical Models ◽  
Removal Rate ◽  
Total Concentration ◽  
Suspended Solid ◽  
Primary Concern ◽  
High Concentration ◽  
Hindered Settling ◽  
Low Concentration ◽  
Solid Distribution

Numerical models for the prediction of turbulent flow field and suspended solid distribution in sedimentation tanks are characterized by refined modeling of hydrodynamics, but apparently weak modeling of settling properties of suspensions. It is known that sedimentation tanks typically treat highly heterodisperse suspensions, whose concentrations range from relatively high to low values. However, settling is modeled either by considering one or more particle classes of different settling velocity, without accounting for hindered settling conditions, or by treating the suspension as monodisperse, even in regions of low concentration. A new generalized settling model is proposed to account for both discrete settling conditions in low concentration regions of the tanks and hindered settling conditions in high concentration regions. Settling velocities of heterodisperse suspensions are then determined as a function of particle velocities in isolation and their total concentration. The settling model is used in the framework of a transport model for the simulation of hydrodynamics and solid distribution in a rectangular sedimentation tank. Results show that solid distribution is mainly affected by particle interactions in the inlet region and by settling properties of individual particles in the outlet region. Comparison of the proposed settling model with other settling models suggests that a generalized approach of the modeling of settling properties of suspensions is a primary concern to obtain reliable predictions of the removal rate.

scholarly journals ASSESSMENT OF GROUNDWATER QUALITY FROM INDUSTRIAL AND RESIDENTIAL AREAS OF SANGO OTA, NIGERIA

2021 ◽  
Vol 46 (2) ◽  
Author(s):  
O.A. Oguntade ◽  
V.I. I Fesiokwu ◽  
O. S. Sule
Keyword(s):  
Electrical Conductivity ◽  
Drinking Water ◽  
Water Samples ◽  
Total Suspended Solid ◽  
Industrial Area ◽  
Suspended Solid ◽  
Residential Area ◽  
Total Hardness ◽  
Residential Areas ◽  
High Concentration

High concentration of contaminants in drinking water can affect human health. This study assessed quality of groundwater at industrial and residential areas of Sango Ota, Ogun State. Water samples were collected in triplicates from 8 wells at industrial and residential areas and analyzed for its physicochemical properties. The pH, electrical conductivity, total dissolved solid (TDS), nitrate, sulphate, total suspended solid (TSS), total hardness (TH), iron, zinc, copper, lead, nickel, chromium and cadmium concentrations in the water samples were determined following American Public Health Association (APHA) procedure. Results showed that pH of 50 % of the wells were lower than minimum limit of 6.5 recommended by WHO. Sulphate, TH and iron in the water were significantly (p < 0.05) higher at residential area than industrial area. Electrical conductivity exhibited significant (p < 0.01) correlation with TDS (r = 0.701**) and NO32- (r = 0.922**) at residential area. At the industrial area however, concentration of salts in water samples was highly associated with SO42- (r = 0.864**) and Cd (r = 0.587**). Across locations of groundwater, iron and lead were above allowable WHO limits in drinking water. Cadmium was also above drinking limit at location T4 of the residential area. Consumers of groundwater in the study area are prone to health related challenges of heavy metal toxicity.

Removal of Oily Wastewater Using Chitosan-filled Filter Media

2015 ◽  
Vol 74 (7) ◽  
Author(s):  
Aziatul Niza Sadikin ◽  
Mohd Ghazali Mohd Nawawi ◽  
Norasikin Othman ◽  
Roshafima Rasit Ali ◽  
Umi Aisah Asli
Keyword(s):  
Palm Oil ◽  
Suspended Solids ◽  
Total Suspended Solid ◽  
Suspended Solid ◽  
Palm Oil Mill Effluent ◽  
Filter Media ◽  
Fibrous Media ◽  
Filtration Process ◽  
Empty Fruit Bunches ◽  
Palm Oil Mill

The aim of this research is to evaluate the feasibility of the fibrous media for removal of total suspended solid and oil grease from palm oil mill effluent (POME). Wet lay-up method was adopted for filter fabrication where empty fruit bunches (EFB) were matted together with chitosan in non-woven manner. Chitosan-filled filter media were tested for their ability to reduce Total Suspended Solids (TSS) and Oil & Grease (O&G) from palm oil mill effluent. Filtration process results indicated that chitosan-filled filter media filtration only removed up to 28.14% of TSS and 29.86% of O&G. 

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