Hotel Service Unit 18 Oil Separators Flashcards

What is the primary purpose of a bilge holding tank in an OWS system?

B) To temporarily store bilge water before processing

What additional information should be recorded about the discharge location in the Oil Record Book?

B) The geographic position (latitude and longitude)

Which other pollutant, aside from NOx, does MARPOL Annex VI aim to reduce due to its greenhouse gas effects?

C) Ozone-depleting substances (ODS)

Which additional component must be present with the oil discharge monitoring system on a vessel of 400 GRT or above?

A) Oil water separator (OWS)

How does a single-stage static OWS ensure compliance with MARPOL Annex I?

C) By ensuring the oil content in discharged water does not exceed 15 ppm

How does an oil detection probe help maintain regulatory compliance?

A) By shutting off discharge if oil content exceeds the allowable limit

Why does MARPOL Annex VI set NOx limits specifically for diesel engines over 130 kW?

B) These engines typically produce higher NOx emissions due to their larger size and power

How does an excessive bilge water feed rate affect the performance of an OWS?

B) It may overwhelm the system, reducing separation efficiency

Why is it essential to control the feed rate of bilge water to an OWS?

B) To maintain optimal separation by giving the system adequate time to process the mixture

What is the primary function of a single-stage static Oily Water Separator in marine applications?

B) To separate oil from bilge water before discharge to meet MARPOL Annex I standards

What is a primary limitation of a single-stage static OWS?

B) It cannot function at high flow rates or with detergent contamination

What is the purpose of a bilge holding tank in an OWS system?

B) To temporarily store bilge water before processing through the OWS

Why is a positive displacement pump preferred over a centrifugal pump as the main bilge pump for an OWS system?

A) It provides a consistent flow rate, regardless of system pressure

What is the purpose of recording the oil content of the mixture when pumping bilges overboard through an OWS?

B) To verify compliance with the 15 ppm oil content limit for discharge

Which engines are required to comply with NOx emission limits under MARPOL Annex VI?

B) All diesel engines over 130 kW installed on vessels

Why is it important to record the quantity of oil-water mixture pumped overboard?

B) To ensure the quantity complies with discharge regulations

Which MARPOL Annex deals with the control of pollution by harmful substances in packaged form?

C) Annex III

How can detergents used for bilge cleaning affect the operation of an OWS?

B) They break down oil particles, making it harder to separate oil from water

What is the purpose of an oil content discharge monitor in conjunction with a single-stage static OWS?

A) To measure and confirm that oil content in the discharge meets MARPOL Annex I limits

Which MARPOL Annex is aimed at controlling pollution by sewage from ships?

B) Annex IV

What system must be fitted on a vessel of 400 GRT or above to comply with MARPOL Annex I?

C) Oil discharge monitoring and control system (ODMC)

What is the primary purpose of an oil detection probe in an OWS system?

B) To detect the presence of oil in bilge water before discharge

Why is an oil content discharge monitor essential in an OWS system?

B) To verify that discharged water meets regulatory oil content limits

Why is an air release fitted to the top of the shell of the OWS?

B) To release any trapped air, which could impede the separation process

Why is it beneficial to have a bilge holding tank on board?

B) It allows for controlled discharge of bilge water when conditions permit

What role does the coalescing plate play in a single-stage static OWS?

C) It helps smaller oil droplets merge into larger droplets for easier separation

Why is it beneficial to use a bilge holding tank before the OWS?

B) It allows bilge water to be stored and processed under appropriate conditions

Why should the discharge overboard line be higher than the OWS?

B) To prevent backflow into the separator

Why is it critical to monitor the oil content of water discharged overboard?

B) To comply with environmental regulations and prevent marine pollution

What is the purpose of an oil content discharge monitor in an OWS system?

B) To ensure discharged water meets the 15 ppm oil content limit

What document must be kept on board as per MARPOL Annex I for vessels above 400 GRT, and why is it required?

B) Oil Record Book – to document oil and oily waste discharges

Which of the following features is essential in the design of a single-stage static OWS?

B) Baffles to promote separation

Why is a positive displacement pump preferred over a centrifugal pump in an OWS system?

C) It maintains a constant flow, essential for effective separation

Which of the following correctly lists one of the MARPOL Annexes?

A) Annex I – Prevention of Pollution by Oil

What is the function of a vacuum breaker in an OWS system?

B) To prevent backflow into the OWS system

Under which condition does a single-stage static OWS operate most effectively?

B) With controlled, low flow rates and minimal detergent presence

Besides NOx, which pollutant is limited by MARPOL Annex VI?

B) Sulfur oxides (SOx)

Which MARPOL Annex focuses on air pollution prevention from ships?

D) Annex VI

Which type of pump is most suitable for use with an Oily Water Bilge Separator (OWS) system, and why?

B) Positive displacement pump, as it provides a constant flow rate

What information must be recorded in the Oil Record Book when bilges are pumped overboard through an oil water separator?

B) Date and time of discharge

What is a significant advantage of using a single-stage static OWS?

C) It is relatively simple and cost-effective compared to multi-stage systems

Why is preventing backflow into the OWS system essential?

B) To prevent contamination of processed water

What is the primary purpose of an oil drain tank in a bilge system?

A) To collect and hold separated oil from the bilge water

How does a single-stage static Oily Water Separator typically separate oil from water?

B) Through gravity separation based on density differences

Why is an oil drain tank important for an OWS system?

A) It ensures separated oil is stored securely until disposal

Why is flow control important in a single-stage static OWS?

B) To allow consistent separation efficiency by controlling bilge water flow rate

What is the primary purpose of an oil content discharge monitor in an OWS system?

B) To measure and ensure that oil content in discharged water meets the legal limit

Why is the Oil Record Book essential on vessels regulated by MARPOL Annex I?

B) It provides evidence of oil handling procedures for compliance and inspection

Why must the flow rate to the Oily Water Separator (OWS) not be exceeded?

B) To ensure efficient oil-water separation without overwhelming the system

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