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Sulphur Oxide Emission Control Areas (SECAs)
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Task 1. Read the text and summarize the methods which will allow the vessels to comply with
Annex YI regulations relating to sailing in SECAs.
Annex VI contains provisions allowing for special “SO Emission Control Areas” (SECAs) to be designated with more stringent control on sulphur emissions. In these areas the sulphur content of fuel oil used on board ships must not exceed 1 % m/m beginning on 1 July 2010; being further reduced to 0.1 %, effective from 1 January 2015. In order to meet these requirements it is often necessary for vessels trading to such areas to have an additional fuel oil storage tank with a fuel of the defined maximum level of sulphur.
The table below is a rough summary of existing SOx emission regulations.
When Ship type Area % Act
19.05.2006 All Baltic SECA 1.5 Marpol
11.08.2006 All Baltic SECA 1.5 EU
11.08.2006 Passenger ships All EU 1.5 EU
11.08.2007 All North Sea+English Channel SECA 1.5 EU
22.11.2007 All North Sea +English Channel SECA 1.5 Marpol
01.01.2010 All All EU ports 0.1 EU
01.01.2010 Inland waterway vessels All EU inland waterways 0.1 EU
01.01.2012 16 Greek ferries Greek ports 0.1 EU
According to Regulation 14(6) of Marpol Annex VI operation in SOx Emission Areas introduces new demands to ship operators, both with respect to bunker management and voyage planning. Almost all ships will continue to operate on high sulphur fuel oil (HSFO) outside the SECAs, mainly due to the high price and low availability of low sulphur bunkers in many ports. These ships will therefore need to switch to low sulphur fuel (LSFO) before entering a SECA. The Regulation requires the ships to allow sufficient time for the fuel oil service system to be fully flushed of all fuels exceeding 1.5 % sulphur prior to entering a SECA. The time it takes to flush the fuel oil (FO) system of fuel oil exceeding 1.5 % depends on the following:
- Sulphur content in high and low sulphur oil,
- Amount of high sulphur fuel between first point of blending and engine inlet, i.e. blending volume, and
- Fuel oil consumption rate.
Blending only takes place in the piping between the service tanks and the inlet to the engine. The settling tank should be emptied (either by pumping the HSFO back to storage or by consumption), and refilled with LSFO prior to entering a SECA. The dilution time can be reduced by minimizing the service and settling tank contents prior to changeover to LSFO, but this will create a risk for a continuous normal operating of the propulsion plant for a safe period of time. Another way is to install new settling and service tanks. The changeover procedure shall be recorded in the engine room log book, i.e. volume of LSFO in each tank, the date, time, and the position of the ship when any fuel changeover operation is completed.
As an alternative Marpol Annex VI, Regulation 14(4b) gives the option of using an exhaust gas cleaning system (EGCS) which reduces the total SOx emissions to 6.0 g/kWh. Special stack-scrubbers for ships are being developed.
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Ships utilizing scrubbers are required to be equipped with continuous emission monitoring equipment.
Task 2. Scan the text above to find the information about:
a) the measures to be taken onboard a vessel before entering a SECA;
b) the way to change over from HSFO to LSFO;
c) an alternative method allowing to obtain the required reduction of SOx emissions.
UNIT 2. SHIPBOARD EQUIPMENT TO PREVENT ENVIRONMENTAL POLLUTION
Text I
Standard Oily Water Separator (OWS).
Task 1. Read and translate the text into Russian using a dictionary.
MARPOL regulations regarding discharge of oil into the sea are becoming more stringent day by day. In this connection oily water separator has become compulsory on all types of ships.
“No ship can sail without an Oily Water Separator”, an annex of MARPOL says. OWS is used to treat an oily water mixture before disposing of it off to the sea. According to MARPOL requirements water that has to be discharged should contain less than 15 parts per million of oil.
Oily water separator SKIT aquaclean “S” (SKIT/S) is type tested and certificated by the Germanischer Lloyd.
OWS utilizes one of completely new flow control principles. The pump which is mounted on the housing of the separator draws water through a basket strainer installed in the suction line from the bilge to protect the OWS and its components against coarse dirt. A non-return valve is installed at the OWS inlet to prevent self-emptying of the system. Coarse separation takes place in the first stage by a process based on the differing densities of oil and water.
A new and extremely porous coalescer efficiently performs fine separation of even the smallest drops of oil due to their extremely oleophile surface. The residual oil content values of less than 1 ppm achieved in the type certification tests prove a very high efficiency of the SKIT separator.
The oil separated out of the water is collected in the upper settling zone of the OWS. An efficient heating system warms this area to support the separation process, to reduce the viscosity of the oil, and to protect the electrodes against clogging by deposits.
The sensor electrode measures the level of the collected oil. When the pre-set level has been reached, the automatic level control will open the oil discharge valve and the backwash water inlet valve and, and the entering backwash water flushes the oil to the oil collection tank. The flushing is followed by the backwash process. The backwash water inlet valve and the backwash water outlet valve will open to backwash the high-performance coalescer with clean water. The standard OWS needs clean water with a feed pressure of max. 1 bar at the backwash water inlet valve. The clean water is also needed for flushing the 15 ppm alarm. Both sea and fresh water are suitable. The consumption of the water is low and depends on oil quantity to be separated out and on the backwash water feed pressure.
The control box containing the automatic controls and electronics is mounted on the separator. Signal lamps on its front panel indicate oil discharge, backwash process, clear water discharge and pump stop. It also contains contacts for two float switches in the bilge. These can be used to start the separating plant depending on the bilge water level.
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The arrangement of the system allows automatic and nearly maintenance-free operation of the oily water separator. During the flushing of the oil and the backwashing sequence the pump heating system is shut down automatically.
Depending on the size of the separator a 15 ppm alarm device Monitor OCD 1M is either mounted on the SKIT separator or is installed close to it to minimize response delays. The distance must not be more than 8 meters; any greater distance will result in a response time over 20 seconds which is the maximum response time in accordance with IMO regulations. The power supply of the plant is controlled by a main switch. All processes are automatically controlled and require no monitoring.
Task 1. Answer the questions to the text you have just read.
1) Which of the annexes to MARPOL 73/78 requires all vessels to be fitted with an oily
water separator?
2) What are the sources of oily water produced on board a ship?
3) What requirements is any oily water separator to meet before it may be installed on a
ship?
4) Where does the separating process begin?
5) How many and what types of filters are employed in the oily water separator in question?
6) Where is a non-return valve installed and why?
7) Is water used in the separator? If yes, what for is it needed?
8) What water is employed and how much of it is required?
9) How is the collected oil level controlled?
10) What is done with the separated oil?
11) Where is the control box mounted?
12) What does it contain?
13) How is the oil content in the cleaned water controlled?
14) What does the place of mounting a 15 ppm alarm device depend on?
15) What maintenance does the plant require?
16) Is it difficult to control and monitor the oily water separator during its operating?
Task 2. Study the diagram below showing possible connections of the OWS system SKIT /S during its installation. Comment on the diagram.
Oily Water Separator Installation Diagram
1. Non-return valve
2. Power supply
3. Control box
4. Oil discharge valve
5. Backwashing discharge valve
9. Sensor electrode
12. Safety valve
13. Effluent outlet
15. Backwashing water supply valve
17. 15 ppm alarm monitor
18. Foot valve with strainer
20. Suction valve
21. Basket strainer
23. Pneumatic three-way valve
24. Overboard stop valve
25. Three-way cock
28. Sample discharge funnel
29. Non-return valve
30. Pressure reducing valve
Text 2
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