轮机英语三管轮试题 造水机.doc

轮机英语Lesson191735. _ is the production of pure water from sea water by evaporation and re-condensing.A. Evaporation B. Circulation C. Condensation D. Distillation1736. When a vacuum boiling evaporator works, the hot jacket water will pass over the tube stack and_ the sea water passing through the tubes.A. dispose B. dissolve C. heat D. dissipates1737. With a vacuum boiling evaporator, the remainder of sea water fed to the evaporator is pumped out by_.A. a brine pump B. an air ejector C. a feed pump D. distillate pump1738. In a vacuum boiling evaporator, the fresh water generated is pumped out by_.A. a brine pump B. an air ejector C. a feed water pump D. a condensate pump1739. When distilling sea water the cooling water discharging from the distiller is fed back to evaporator as feed water_.A. to decrease scale formation B. for better cooling effectC. for more economical purpose D. to raise vacuum1740. When distilling salt water the cooling water discharging from the distiller is fed back to evaporator as feed water_.A. to cut down the amount of cooling water neededB. to prevent an excess amount of cooling water from being discharged to the bilgesC. to supply hot water to the evaporator for more economical operationD. None of the above is tree.1741. The process during which liquid containing a reasonable amount of sensible heat at a particular pressure immediately changes into steam after admitted to a chamber at a lower pressure is called_.A. boiling off B. flash evaporation C. condensation D. none of the above1742. In the process of_, liquid changes into gas.A. evaporation B. frosting C. condensing D. compressing1743. Which of the following is NOT on the list items to be recorded in Oil Record Book Part I (machinery space operation)?A. Accidental discharge of oil. B. Disposal of oil residues.C. Quantity of water produced by F. W. G.D. Discharge of dirty ballast or cleaning water from fuel oil tanks.1744. When the water produced from most evaporator is supplied for drinking purpose, it must be treated to ensure it is biologically pure and_.A. slightly acidic B. slightly alkaline C. no salty D. slightly bitter1745. _ provides the head or pressure to supply the domestic water where required.A. The compressed air B. The compressing air C. The transfer pump D. The head tank1746. _ is used for washing and drinking.A. The ballast system B. The salt water system C. The bilge system D. The domestic system1747. Water evaporates or steam condenses at the saturation temperature, which depends upon the pressure, the higher the pressure_ the saturation temperature.A. the more B. the higher C. the lower D. the highest1748. We use_ to distill fresh water from sea water.A. engine B. sea water pump C. cylinder cooler D. fresh water generator1749. Because of the reduced_ in the vacuum boiling evaporator, some of the sea water boils as it flows through the tubes.A. temperature B. water level C. pressure D. rate of flow1750. The fresh water generator produces fresh water_.A. by cooling sea water B. by heating sea waterC. by evaporation of sea water D. by purifying sea water1751. Clean oil is achieved in a clarifier bowl where the impurities and water collect at the bowl_.A. bottom B. top C. center D. periphery1752. The designed capacity is 25 tons a day, but the fresh water generator can only_ 22 tons at present.A. consume B. distill C. run D. operate1753. More than one stage of evaporation can take place by admitting the sea water into chambers with progressively_ pressure in the flash evaporator.A. lower B. higher C. the lower D. the higher1754. Because of the reduced_ in the distillation system, some of the sea water boils as it flows through the tubes of the evaporator.A. pressure B. temperature C. density D. volume1755. In_, hot diesel engine jacket water passes over the stack and heats the sea water passing through the tubes.A. a flash generator B. a flash evaporator C. a vacuum boiling evaporator D. a boiler1756. Which of the following statements is true concerning any evaporator?A. High conductivity of the distillate indicates distillate salinity is excessive.B. Increasing the absolute pressure of the shell will increase the distillers capacity.C. Mesh separators are used in evaporators to filter the distillate.D. Reducing the brine density will reduce the heat lost overboard.1757. The process of boiling seawater in order to separate it into freshwater vapor and brine is usually defined as_.A. dehydration B. condensation C. evaporation D. dissolution1758. When a flash-type evaporator is to be secured for an extended period of time, the entire unit should be drained, cleaned, and_.A. completely filled with saltwater B. filled with de-scaling compoundC. tightly closed to exclude air D. vented to the atmosphere1759. Which of the following descriptions best identifies the operating principal of a flash-type evaporator?A. Sea water is heated to boiling temperature while under a vacuum.B. Sea water is passed over heated plates in a thin film.C. Heated sea water is injected into a vacuum chamber.D. Sea water is forced through a heated eductor.1760. Which of the listed problems could produce a high absolute pressure within a flash type evaporator?A. Production of high salinity distillate .B. Seawater feed temperature below 165oC.C. A leak in the first stage demister .D. A cracked distillate pump vent line.1761. Distilled water from an evaporator may be discharged into a potable water(饮用水)tank _.A. through a detachable hose connection B. after passing through an activated charcoal filterC. after chemical analysis shows it is fit for consumptionD. through a solenoid operated three-way valve1762. Which of the following statements is correct relative to distillation plant operation?A. Distillation is the process of boiling seawater to produce vapor which is condensed into fresh water.B. Evaporation is the second part of the distillation process where brine is removed.C. Brine is the result of condensed sea water vapor.D. Distillate is the product resulting from the evaporation of fresh water vapor.1763. Brine density in a distilling plant is measured with a/an_.A. psychrometer B. salinometer C. anemometer D. sphygmomanometer1764. Tube leaks in the distillate cooler of a two stage flash evaporator will result in_.A. loss of second stage vacuum B. contamination of the distillateC. lower feed inlet temperature D. contamination of the second stage condenser1765. Why will a two stage flash type distilling plant tend to operate more efficiently when operating in cold seawater?A. The colder seawater passing through the condenser tube bundles of the various stages increases evaporator vacuum.B. The amount of heated feed water discharged from the feed water heater after condenser is increased.C. Fewer non-condensable gases are created by the flow of colder seawater.D. More seawater is allowed to pass through the flint stage overflow weir.1766. One distinct advantage of flash type evaporators, as compared to most other evaporators, is that in a flash evaporator_.A. high temperature distillate can be re- circulated to induce additional flashingB. scale formation is not a severe problemC. cold shocking is more effective in removing scaleD. water purity is greatly increased at high capacity1767. Less scale formation occurs in a flash evaporator than in a submerged tube evaporator because_.A. the distillate produced has greater purity B. no boiling occurs on heat transfer surfacesC. evaporation occurs at a higher rate D. the incoming feed is at a higher temperature1768. The primary reason low pressure evaporators produce distillate more efficiently, and with less scale formation, than high pressure evaporators is_.A. evaporation is accomplished in a vacuum B. due to the higher temperature of the incoming feedC. due to the latent heat of evaporation principleD. evaporation in a submerged medium produces more distillate1769. A vacuum is initially created in a flash type distilling plant by_.A. the flashing of the feed water B. the condensation of the saltwater feedC. air ejectors, eductors, or a separate vacuum pump D. condensation of the distillate1770. Scale accumulation on evaporator heat exchange surfaces_.A. increases brine density B. increases distillate salinityC. reduces metal corrosion D. reduces heat transfer1771. Excessive scale formation in a distilling plant may result from_.A. poor distillate quality B. reduced evaporator capacityC. low brine concentration D. improper vacuum regulation1772. Which of the listed conditions will cause the feed water, that has not flashed to vapor in the first-stage of a flash evaporator, to flow into the second-stage?A. Gravity siphon effect. B. Higher vacuum in the second-stage.C. Difference in brine density between first and second stages. D. lower pressure in first-stage.1773. The vacuum maintained in the salt water feed heater shell of a flash-type evaporator is generally accomplished by_.A. a separate air ejector unitB. a direct unimpeded connection between second stage and salt water feed heaterC. either by vacuum drag or an external line from the first stage via a fixed orificeD. the fixed orifice provided in the steam supply line1774. In which of the areas listed would you expect to find the highest salt concentration in a flash evaporator?A. Distiller air ejector cooling medium. B. Saltwater heater discharge.C. First-stage internal feed box. D. Second-stage internal feed box.1775. On which of the following heated surfaces of a flash type evaporator would you be more likely to find soft scale formation?A. Feed-water heater internal tube surfaces. B. Internal distillate cooler tubes.C. Flash chamber vertical surfaces. D. Distilling condenser tubes.1776. Which of the conditions listed represents the greatest effect of excess frost accumulation on the evaporator coils?A. Keeps the refrigerated space cooler. B. Reduces the efficiency of the plant.C. Takes the load off the compressor. D. Has no affect on the system.1777. Which statement concerning the collection of fresh water is FALSE?A. Fresh water may be obtained from fish.B. lifeboat covers or canopies should be washed with rain before drinking water is collected.C. Fresh water may be collected from condensation inside the life-raft.D. Freshwater cannot be produced from standing seawater.1778. Seawater may be used for drinking water_.A. at a maximum rate of two ounces per day B. after mixing with an equal quantity of fresh waterC. if gather during or immediately after a hard rain D. under no circumstance1779. Distilled water is now largely used on board, this may be corrosive (due to presence of dissolves CO2) and_ to the taste.A. flat B. slat C. sweet D. acid1780. A flash-type evaporator discharges heated seawater into a chamber that is maintained at a pressure _ than the vapor pressure of the entering heated seawater, and subsequently the flashed water vapor thereby produced.A. lower condensing B. higher cooling C. lower cooling D. higher condensing1781. The design of _for a flash type evaporator is of critical importance because it must provide an optimum feed water spray pattern that facilitates the flashing process, and it must also maintain a pressure differential between successive stages.A. condenser B. flashing device C. lashing device D. vacuum pump1782. Which one of the following might not be employed to create vacuum for flash type evaporator_.A. high-pressure steam-driven air-ejector B. motor-driven vacuum pumpC. water-motivated air educator D. centrifuge pump1783. The flash-evaporator is different with the submerged-tube evaporator in that for the former_.A. Water is heated into vapor on heating surfaces B. Water is vaporized by pressure differenceC. There are no heating-transfer surfaces D. There are more heating-transfer surfaces1784. For a flash type evaporator, the seawater heater will have to maintain a _enough temperature to minimize scale formation.A. lower B. higher C. low D. high1785. For a flash type evaporator, a demister is located _the condenser.A. after B. before C. inside D. outside 1786. The efficiency and output capacity of a low pressure distilling plant will bereduced if the last effect shell _.A pressure does not fluctuate rapidly B pressure remains steady and unchanged C brine density does not exceed 1.5 D brine density is too low 1787. The heated feed water entering any flash chamber of a flash-type evaporator will _.A vaporize, with the unflashed water remaining at the temperature at which itentered the flash chamber B vaporize, with the unflashed water equalizing to the saturation conditions existing in the flash chamberC vaporize, with the remaining water at a temperature greater than it entered the flash chamberD boil, allowing steam bubbles to rise through the brine at the bottom of the flash chamber1788. The three basic parts of any eductor are the nozzle, the suction chamber, and the _.A injector B compressor C diffuser D siphon 1789. _ is based upon the biological process of osmosis, which allows fluids to pass through a semi permeable membrane.A. Flash B. Reverse osmosis C. Boiling off D. Distillation1790. The desalination of water by _is a membrane separation process in which the water from a pressurized saline solution (seawater) is forced through a synthetic semi-permeable membrane leaving its salts behind (dissolved solids) A. distillation B. flash C. reverse osmosis D. boiling off1791. The function of the _is to convert seawater into fresh water by vacuum distillation, for the supply of high quality fresh water for domestic and process utilization. A. oily water separator B. incinerator C. fresh water generator D. centrifuges1792. The efficiency of a flash type evaporator can be increased by _ A. lowering brine discharge density B. decreasing the absolute pressure of each stage C. increasing the saltwater feed heater temperature D. increasing the pressure at the spray pipe 1793. The second stage feed water temperature and shell absolute pressure in a multistage, flash type, distilling plant is _A. higher than the first stage feed water temperature and absolute shell pressure B. lower than the first stage feed water temperature and absolute shell pressure C. the same as the first stage feed water temperature and absolute shell pressure D. not related to the feed water temperature and absolute shell pressure1794. On a multistage flash type evaporator, the flash chamber is _A. combined as part of the salt water feed heater B. the open area above the brine levels in the first and second stagesC. combined as part of the distillate cooler D. another term used to describe the vapor feed heater 1795. Which of the listed chemicals can be routinely used to maintain the hygienic quality of potable water?A. hydrochloric acid B. chlorine C. sulfuric acid D. zinc chromate1796. Drops of sea water removed by demister _in the fresh water generator.A. fall due to gravity in to the brine sump B. fall due to gravity in to the evaporation section C. are removed by fresh water generator D. are removed by sea water generator1797. The hot water in let and outlet valves in the fresh water generator should be open _during the starting process.A. when there is minimum of 90% vacuum B. before starting the ejector pumpC. when there is a minimum of 30% vacuum D. after stop the ejector pump1798. The combined brine/air ejector in fresh water generator is supplied by _creates a vacuum in the system in order to lower the evaporation temperature of the feed water.A. the fresh water pump B. the feeding pump C. the compressed air installation D. the separate vacuum pump1799. The air valve installed on the upper part of the fresh water generator_ A. should be open during vacuum creation procedure B. should be open after stopping the plants C. should remain closed all the time D. should remain open all the time1800. The combined brine/air ejector creates a vacuum in fresh water generator in order to_A. increase the evaporation temperature of the feed-waterB. decrease the evaporation temperature of the feed-water C. decrease the temperature of the feed-water D. increase the evaporation temperature of the feed-water1801. The ejector pump used in the fresh water generator will_A. discharge brine over water B. supply condenser only C. feed the evaporator D. circulate seawater between condenser and evaporator 1802. The fresh water generator with a vacuum of _allowing the brine to evap