Eliminating Discharges in Oil/Sea Interfaces - a Return to Seawater Lubricated Propeller Shaft Systems for Commercial Ships

2015 ◽  
Author(s):  
Craig D. Carter
Keyword(s):  
New York ◽  
Oil Pollution ◽  
Operating Costs ◽  
General Description ◽  
Propeller Shaft ◽  
Environment Protection ◽  
Protection Agency ◽  
New Classification ◽  
Shaft System ◽  
Standard Designs

Oil discharges from a ship’s propeller shaft system are an issue for commercial ship owners. A 2010 study by a New York Consulting firm estimated the total worldwide amount of lubricants from operational discharges from ships would be about 130 to 244 million litres annually. To add perspective, oil pollution from the Exxon Valdez tanker spill in 1989 was 41.6 million litres. Most ships use mineral oil to lubricate the propeller shaft and the oil is contained in the propeller shaftline by the aft seal – which is the oil to sea interface. According to the new U.S. Environment Protection Agency Vessel General Permit (VGP), all vessels built on or after Dec. 19, 2013 and trading in US waters must use an environmentally acceptable lubricant (EAL) in all oil to sea interfaces before their next drydocking. This paper will review: the renaissance of seawater based systems, a general description of a seawater lubricated bearing system, current commercial ship users and results, lower operating costs with “free” seawater and no aft seal, conversions of existing ships and resistance of shipyards to change standard designs from oil to seawater. The paper will also review new Classification rules from LR, CCS and BV for seawater lubricated propeller shaft systems, allowing the shaft to remain in place if monitoring conditions are met - which removes a major obstacle that ship owners had with seawater-based propeller shaft bearing systems.

Effects of Charging Infrastructure and Non-Electric Taxi Competition on Electric Taxi Adoption Incentives in New York City

2019 ◽  
Vol 2673 (4) ◽  
pp. 262-274 ◽  
Author(s):  
Jaeyoung Jung ◽  
Joseph Y. J. Chow
Keyword(s):  
New York ◽  
New York City ◽  
York City ◽  
Operating Costs ◽  
Charging Infrastructure ◽  
Trade Offs ◽  
Average Revenue ◽  
The Individual ◽  
Queue Delay ◽  
Charging Stations

With major investments in electric taxis emerging around the world, there is a need to better understand resource allocation trade-offs in subsidizing electric vehicle taxis (e-taxis) and investing in electric charging infrastructure. This is addressed using simulation experiments conducted in New York City: 2016 taxi pickups/drop-offs, a Manhattan road network (16,782 nodes, 23,337 links), and 212 charging stations specified by a 2013 Taxi & Limousine Commission study. The simulation is based on a platform used to evaluate taxi operations in California and Seoul. Eleven scenarios are analyzed: a baseline of 7,000 non-electric taxis, five scenarios ranging from 1,000 e-taxis to 5,000 e-taxis, and another five scenarios in which the e-taxis have infinite chargers as an upper bound. The study finds that the number of charging locations recommended in the earlier study may be insufficient at some locations even under the 3,000+ e-taxi scenarios. More importantly, despite an average revenue of $260 per taxi for the 7,000 non-electric taxis and about $247 per taxi for electric taxis over the finite charger scenarios, the revenue gap between e-taxis and non-electric taxis in a mixed fleet increases significantly as the e-taxi share increases. This is because the increasing queue delay imposed on e-taxis gives non-electric taxis an increasing competitive advantage, raising their average revenue from $260 per taxi (1,000 e-taxis) up to $286 per taxi (5,000 e-taxis, 150% revenue gap increase), all other operating costs being equal. This has implications for individual versus whole-fleet policies, as the individual-oriented policies may be less effective.

scholarly journals Assessment of Some Heavy Metals in Drinking Water Samples of Tunceli, Turkey

2011 ◽  
Vol 8 (1) ◽  
pp. 276-280 ◽  
Author(s):  
Olcay Kaplan ◽  
Nuran Cikcikoglu Yildirim ◽  
Numan Yildirim ◽  
Nilgun Tayhan
Keyword(s):  
Heavy Metals ◽  
Drinking Water ◽  
Water Samples ◽  
World Health ◽  
Environment Protection ◽  
Protection Agency ◽  
Supply Networks ◽  
Health Organization ◽  
The City ◽  
Drinking Water Samples

The drinking water quality is associated with the conditions of the water supply networks, the pollution and the contamination of groundwater with pollutants of both anthropogenic and natural origin. In this study, water samples were taken from four different waterworks in Tunceli, Turkey and heavy metals concentrations (As, Cu, Cd, Cr, Pb, Ni and Hg) were measured. Four sampling sites were pre-defined in different locations of the city. The obtained results showed that, the heavy metals concentrations in water samples did not exceed the values of WHO (World Health Organization), EC (Europe Community), EPA (Environment Protection Agency) and TSE-266 (Turkish Standard) guidelines.

Non-Linear Coupled Dynamics of a Flexible Propeller-Shaft System Supported by Water Film Bearings

2020 ◽  
Vol 142 (3) ◽  
Author(s):  
Chang-Gang Lin ◽  
Ming-Song Zou ◽  
Can Sima ◽  
Li-Bo Qi ◽  
Yue Yu
Keyword(s):  
Nonlinear Vibration ◽  
Damping Ratio ◽  
Water Film ◽  
Vibration Characteristics ◽  
Superposition Method ◽  
Propeller Shaft ◽  
Chaotic Motions ◽  
Mode Superposition Method ◽  
Shaft System ◽  
Slice Method

Abstract A slice method to determine the boundary conditions between the stern bearing and shaft by dividing the journal in the stern bearing into several slice elements along the axial direction is proposed for the first time. A comprehensive finite element model considering the nonlinear force of the water film and the flexibility of the propeller blade is established for a propeller-shaft system. The long bearing approximation is adopted to calculate the pressure distribution around each journal element in the stern bearing. The mode superposition method is employed. The nonlinear equation of motion is solved iteratively using the Newmark method. A parametric study is implemented to analyze the nonlinear vibration characteristics of the system. It is shown that the real motion state of the journal in the stern bearing can be simulated more precisely by the slice method proposed. The responses of the system alternate among period-one, quasi-periodic, multi-periodic, and chaotic motions as the rotating speed increases. The damping ratio has a significant effect on the dynamic characteristics of the propeller-shaft system. The motion of the system is unstable when the damping ratio is very small. At this time, the modes of the flexible propeller blades can be excited readily. The slice method, which can also be extensively used in similar rotor-bearing systems in the engineering field, is very simple and efficient to analyze the nonlinear vibration characteristics of a flexible propeller-shaft system supported by water film bearings.

U.S. Environmental Protection Agency/U.S. Coast Guard Peer Exchange Program1

1999 ◽  
Vol 1999 (1) ◽  
pp. 1137-1139
Author(s):  
Jeffrey C. Babb ◽  
Glenn Cekus
Keyword(s):  
Environmental Protection ◽  
Environmental Protection Agency ◽  
Oil Pollution ◽  
Coast Guard ◽  
Leadership Roles ◽  
Environmental Response ◽  
Protection Agency ◽  
Response Planning ◽  
Response Team ◽  
The U.S

ABSTRACT Nationwide, the U.S. Coast Guard (CG) and the U.S. Environmental Protection Agency (EPA) are both tasked with the implementation of several environmental and safety statutes (Comprehensive Environmental Response, Compensation, and Liabilities Act [CERCLA], Oil Pollution Act of 1990 [OPA 90], Clean Water Act [CWA], international Convention for the Prevention of Pollution from Ships [MARPOL], etc.). They share important leadership roles on the National Response Team (NRT), Regional Response Team (RRT) and several other response planning bodies. Often EPA On-Scene Coordinators (OSCs) and CG OSC representatives work together in oil and chemical response operations and on various planning and exercise committees. However, the joint efforts of both organizations are often impacted by a mutual lack of understanding of each other's authorities, policies, procedures, internal structures, and leadership roles. Even the response zones for CG and EPA are often based on factors other than geography and often may not be well understood. USCG Marine Safety Office (MSO) Chicago and EPA Region V are bridging this gap in understanding by sponsoring a Peer Exchange Program. Representatives from each agency are spending up to a week with the other agency for hands-on training and education. The program was initiated in April 1996 and has produced excellent results. As a result, joint CGIEPA responses run more smoothly, mutual understanding and accessibility are enhanced, and overall public health and welfare and the environment are better protected.

scholarly journals BIOACCUMULATION OF ORGANOCHLORINES PESTICIDES (OCP) COMPOUND IN GREEN MUSSELLS (Perna viridis) IN JAKARTA BAY

2016 ◽  
Vol 8 (1) ◽  
Author(s):  
. Edward
Keyword(s):  
Organochlorine Pesticides ◽  
Organochlorine Pesticide ◽  
Threshold Limit Value ◽  
Average Concentration ◽  
Medium Size ◽  
Perna Viridis ◽  
Environment Protection ◽  
Protection Agency ◽  
Green Mussel ◽  
Limit Value

<p align="center"><strong><em>ABSTRACT</em></strong></p><p><em>The green mussel, Perna viridis can be used to determine bioaccumulation levels of organochlorine pesticides in a marine environment. Measurements on pesticide organochlorine concentration in green mussels (Perna viridis) were conducted in March and  May 2013. The purpose of this research was to determine the bioaccumulation level of organochlorine pesticides in green mussels which were  cultivated in Jakarta Bay. The samples were collected in Jakarta Bay in March and May 2013. The organochlorine pesticides concentration were measured  by gas chromatography HP 5890 series II. The results showed that the average concentration of organochlorine pesticides in the small size of green mussells was 12.842 ppb, in the medium size was 27.065 ppb, and in the big size was 108.646 ppb. These concentrations were still lower than safety threshold limit value for seafood stated by EPA (Environment Protection Agency) i.e., 1,500 ppb. The comparation between organochlorine pesticide concentration in seawater and organochlorine pesticide in green mussels (bioaccumulation factor) were 2,140 for small green mussel, 4,510 for medium green mussel, and 18,107 for big green mussels, respectively.</em></p><p><strong><em>Keywords</em></strong>: <em>bioaccumulation, green musselss, organochlorine pesticide, Jakarta Bay </em></p>

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