When a tank is to be gas freed after washing，the concentration of hydrocarbon vapour should be reduced by purging the inerted cargo tank with ______．A.the oxygenB.the gasC.the inert gasD.the hydrocarbon vapour
When a tank is to be gas freed after washing，the concentration of hydrocarbon vapour should be reduced by purging the inerted cargo tank with ______．
A.the oxygen
B.the gas
C.the inert gas
D.the hydrocarbon vapour
相关考题：
Which three statements are true about memory buffer allocation by a MySQL Server?() A.Global buffers such as the InnoDB buffer pool are allocated after the server starts, and are never freedB.Thread buffers are allocated when a client connects, and are freed when the client disconnectsC.Buffers that are needed for certain operation are allocated when the operation starts, and freed when it endsD.User buffers are allocated at server startup and freed when the user is droppedE.All dynamic buffers that are set with a SET GLOBAL statement immediately get allocated globally, and are never freed
How should cargo tank hatches be protected when the ullage opening is open and the tank NOT gas free?A.With gooseneck ventsB.With warning signsC.With flame screensD.With pressure-vacuum relief valves
A cargo tank that is initially gas freed，can be inerted by introducing inert gas by a process known as ______.A.dilutionB.displacementC.precipitationD.Either A or B
You are cleaning the tanks after carrying a cargo of crude oil. Which statement is TRUE?A.Washing water should be recirculated if possible because it has the same electric potential as the cargo tank being cleanedB.The hoses to portable cleaning machines should be disconnected before the machines are removed from the tankC.The principal hazard with steaming cargo tanks is raising the ambient temperature above the flame point of the cargo residueD.Steam cleaning and water washing are both capable of generating electrostatic charges within a tank
Which step is NOT generally taken when gas-freeing a tank? ______.A.Washing the tank interior with sea waterB.Application of degreasing solventsC.Removal of corrosion products and sludgeD.Fresh air ventilation
You are testing a tank that contained gasoline by using a combustible gas indicator．Under testing，the tank sample caused the needle to move rapidly to 100 on the dial then fall to zero．What is the concentration of flammable gas ________．A.Less than the flammable rangeB.Within the flammable rangeC.Over the flammable rangeD.The explosimeter is defective and giving a false reading
Inerting means ______．A.The introduction of inert gas into a tank with the object of reducing the oxygen content to below 8% by volumeB.The introduction of inert gas into a gas free tank for the purpose of reducing the oxygen content to below 8% by volumeC.The introduction of inert gas into a cargo tank during cargo discharge to replace the volume of discharged cargoD.All of the above
The deck water seal of the inert gas system ______．A.Cools the inert gas and prevents soot from entering the cargo tanksB.Acts as an emergency shutdown when inlet pressures exceed the safe working pressureC.Prevents the backflow of hydrocarbon gasses into nonhazardous areasD.Relieves sudden large overpressures in the system
What is NOT a requirement for the safe and effective use of a crude oil washing system ________．A.Strip all tanks and remove the bottom residueB.Use an inert gas system while washing tanksC.Use portable washing machines to reach areas obscured by structural members in the tanksD.Debottom the tank used as the source for the tank cleaning machines
When a non-volatile cargo is carried in a tank that has not been previously gas freed，then that tank shall ______．A.be purged with hydrocarbon gas prior to loadingB.be gas-freed after loading operationsC.not be maintained in an inert conditionD.be maintained in an inert condition
Which statement about inert gas pressures in a cargo tank is TRUE ________．A.The pressures of the inert gas in the tank may create excessive pressure at the pump while dischargingB.Gas pressures should be maintained at the highest permissible level throughout the discharging processC.High gas pressures may cause pyrophoric oxidation in the tankD.High gas pressures may cause loss of suction when stripping
When the inert gas pressure is being ______ in the cargo tanks，particular attention should be paid to obtaining an oxygen concentration．A.topped upB.bracedC.tommed downD.shored
You are planning to use a crude oil washing system．What precaution must be taken with the tank as the source for the washing machines ________．A.It must be debottomed and the level lowered by at least one meterB.The oil in the source tank must be sampled for compatibilityC.The source tank must have been crude oil washed at least once in the past 150 daysD.The inert gas system must lower the oxygen content to a maximum of 12% oxygen in the tank
______is not one of the most important environmental factors that influence hydrocarbon biodegradation．A.temperatureB.concentration of nutrientsC.nitrogenD.oxygen
An inert gas system is designed to reduce the possibility of tank explosions by ______.A.eliminating sparks and fire in the vicinity of cargo tanksB.removing all hydrocarbon gases from the cargo tanksC.blanketing cargo tanks with inert foamD.reducing the oxygen concentration below levels necessary for combustion
Which three statements are true about memory buffer allocation by a MySQL Server?（）A、Global buffers such as the InnoDB buffer pool are allocated after the server starts, and are never freedB、Thread buffers are allocated when a client connects, and are freed when the client disconnectsC、Buffers that are needed for certain operation are allocated when the operation starts, and freed when it endsD、User buffers are allocated at server startup and freed when the user is droppedE、All dynamic buffers that are set with a SET GLOBAL statement immediately get allocated globally, and are never freed
单选题Which of the following represents the maximum percent of oxygen by volume required to be achieved by a ship’s inert gas system, prior to the commencement of crude oil tank washing?（）A6%B8%C10%D12%
单选题The deck water seal of the inert gas system（）.Acools the inert gas and prevents soot from entering the cargo tanksBacts as an emergency system shutdown when the inlet pressures exceed the safe working pressure in the hazardous zoneCprevents the backflow of hydrocarbon gasses into nonhazardous areasDrelieves sudden large overpressures in the system
单选题An inert gas system is designed to reduce the possibility of tank explosions by（）.Aeliminating sparks and fire in the vicinity of cargo tanksBremoving all hydrocarbon gases from the cargo tanksCblanketing cargo tanks with inert foamDreducing the oxygen concentration below levels necessary for combustion
单选题A cargo tank that is initially gas freed，can be inerted by introducing inert gas by a process known as（）.AdilutionBdisplacementCprecipitationDEither A or B
单选题What action must be taken when an individual cargo tank is closed off from the inert gas system by the tank isolation valve?（）AThe tank must be gas freedBThe tank must be ballastedCThe tank must be vented to the atmosphereDThe bypass valve must also be closed
单选题Which step is NOT generally taken when gas-freeing a tank?（）.AWashing the tank interior with sea waterBApplication of degreasing solventsCRemoval of corrosion products and sludgeDFresh air ventilation
多选题Which three statements are true about memory buffer allocation by a MySQL Server?（）AGlobal buffers such as the InnoDB buffer pool are allocated after the server starts, and are never freedBThread buffers are allocated when a client connects, and are freed when the client disconnectsCBuffers that are needed for certain operation are allocated when the operation starts, and freed when it endsDUser buffers are allocated at server startup and freed when the user is droppedEAll dynamic buffers that are set with a SET GLOBAL statement immediately get allocated globally, and are never freed
单选题Inerting means（）.Athe introduction of inert gas into a tank with the object of reducing the oxygen content to below 8% by volumeBthe introduction of inert gas into a gas free tank for the purpose of reducing the oxygen content to below 8% by volumeCthe introduction of inert gas into a cargo tank during cargo discharge to replace the volume of discharged cargoDAll of the above
单选题Hydrocarbon vapors are usually detected by the use of the （）.Aflame safety lampBcombustible gas indicatorCgasometerDoxygen indicator
单选题The deck water seal of the inert gas system（）.Acools the inert gas and prevents soot from entering the cargo tanksBacts as an emergency shutdown when inlet pressures exceed the safe working pressureCprevents the backflow of hydrocarbon gasses into nonhazardous areasDrelieves sudden large overpressures in the system