Difference between purifiers and clarifier

What are centrifuges?

A centrifuge is a device that uses centrifugal force to separate component parts of a fluid. This is achieved by rotating the fluid at high speed within a container, thereby separating fluids of different densities (e.g. cream from milk) or liquids from solids.

• It works by causing denser substances and particles to move outward in the radial direction.
• At the same time, objects that are less dense are displaced and move to the center.
• In ships, we use two types of centrifuges ie. purifier and clarifiers 

Definition

• Purifier is a type of centrifugal separator that we can use to separate two liquids with different densities 
• Clarifier is a type of centrifugal separator that we can use to separate solid impurities from fuel.

The main difference between the two

Purifier

1. In a purifier there exists an inference or a line separation between the oil and water, this is achieved using a dam ring. the position and the diameter of the dam ring plays a major role in the creation and maintenance of interface line
2. Purifier needs to be filled completely with sealing water for the generation of a seal that prevents the oil to leave from the water outlet
3.  The conical disc has feed holes/distribution holes to help with the interface
4. It has two outlets clean oil outlet and water outlet
5. Generally used for lubricating oil

If the interface is broken or misplaced water can go into the clean oil outlet or oil can enter the water outlet, hence disturbing the purification process 

Clarifier

1. In a clarifier, there is no interface between oil and water, this is achieved by using a sealing ring, which seals the water outlet. this allows the water and impurities to stay within the bowl and is discharged when the bowl disludges
2. The clarifier doesn’t need to be filled up with sealing water.
3. The conical discs in a clarifier usually don’t have feed holes in them but if they do, then a disc without any holes is fitted at the bottom of the stack.
4. It has only one outlet clean oil outlet
5. Generally used for fuel oil depending on fuel density and design

World cap for sulfur content for Fuel

On 1 January 2020, the global sulphur limit on marine fuels will be reduced from 3.50% to 0.50% m/m(mass by mass) sulphur.

• The IMO has decided that the global fuel sulphur limit of 0.50% will enter into force in 2020.
• This requirement is in addition to the 0.10% sulphur limit in the North American, US Caribbean, North Sea and Baltic Sulphur Emission Control Areas (SECAs). 
• Vessels that have exhaust gas cleaning systems installed will be allowed to continue using high-sulphur fuel oil (HSFO).

Are there any exemption

• If the ship cannot obtain compliant fuel oil.
• They can complete a fuel oil non-availability report(FONAR). 
• This can be taken into account by port state control but this is not an exemption

Is a (FONAR) a waiver -Short answer-​No. 

long answer

The 2019 Guidelines on consistent implementation of 0.50% sulphur limit under MARPOL Annex VI adopted by resolution MEPC.320(74) here clearly states (in APPENDIX 1):

3.1 A fuel oil non-availability report is not an exemption. According to regulation 18.2 of MARPOL Annex VI, it is the responsibility of the Party of the destination port, through its competent authority, to scrutinize the information provided and take action, as appropriate."

3.2 In the case of insufficiently supported and/or repeated claims of non-availability, the Party may require additional documentation and substantiation of fuel oil non-availability claims. The ship/operator may also be subject to more extensive inspections or examinations while in port."

3.3 Ships/operators are expected to take into account logistical conditions and/or terminal/port policies when planning bunkering, including but not limited to having to change berth or anchor within a port or terminal in order to obtain compliant fuel."

3.4 Ships/operators are expected to prepare as far as reasonably practicable to be able to operate on compliant fuel oils. This could include but is not limited to, fuel oils with different viscosity and different sulphur content not exceeding regulatory requirements (requiring different lube oils) as well as requiring heating and/or other treatment on board."

What is the "carriage ban" 

• Carriage of Fuel Oil for use onboard ships will be prohibited from 1st march 2020 if sulfur content exceeds 0.50%, unless the ship has approved scrubber system,

sources:http://www.imo.org

Regulation for SCABA (FSS code)

• SCBA may be either of the negative demand or positive pressure type or may have a changeover facility to allow operation in either mode.
• The volume of air contained in the SCBA cylinders should be at least 1,200 litres, which shall be capable of providing air for at least 30 minutes.
• Two spare charges suitable for use with the apparatus should be provided for each apparatus required.
• As a requirement approved SCBA sets must be fitted with a low pressure warning device and pressure indicator.
•  Each breathing apparatus should be provided with a flexible fireproof lifeline, type approved to meet the testing standards quoted in the Marine Equipment Directive, of at least 30 m in length,The lifeline should be subjected to a test by static load of 3.5 kN for 5 minutes.

NEW REGULATION FOR FIRE FIGHTER COMMUNICATION

For ships constructed on or after 1 July 2014, a minimum of two two-way portable radiotelephone apparatus for each fire party for firefighter's communication shall be carried on board

• Those two-way portable radiotelephone apparatus shall be of an explosion-proof type or intrinsically safe.
•  The purpose of these specific radios is to provide a dedicated means of communication between a team of fire fighters entering the space, and the crew member located outside the space who is assigned to control this team, i.e. one Fire Party
• Intrinsically safe radios should have a power output of 1 watt or less. It is the ship's responsibility to demonstrate that the radios are fit for purpose, i.e. that they are able to work within the environment to be expected in a fire scenario, that their operating range is sufficient and that they are safe. 

MLC REGULATION FOR WORK AND REST HOURS

Maximum hours of work shall not exceed:

• 14 hours in any 24-hour period; and
• 72 hours in any seven-day period;

or

Minimum hours of rest shall not be less than:

•  ten hours in any 24-hour period; and
• 77 hours in any seven-day period.

2. Hours of rest may be divided into no more than two periods, one of which shall be at least six hours in length, and the interval between consecutive periods of rest shall not exceed 14 hours.

3. Musters, fire-fighting and lifeboat drills, and drills prescribed by national laws and regulations and by international instruments, shall be conducted in a manner that minimizes the disturbance of rest periods and does not induce fatigue.

4. When a seafarer is on call, such as when a machinery space is unattended, the seafarer shall have an adequate compensatory rest period if the normal period of rest is disturbed by call-outs to work.