MARINE ENGINEERING Flashcards
- refers to the point where high-pressure steam enters the heat exchanger unit.
- The steam inlet is where the steam is introduced into the heat exchanger, and it typically connects to a steam supply line.
- it is where the heat transfer process begins, and it plays a crucial role in many industrial applications where temperature control is necessary.
STEAM INLET
- holds the tubes in place
- barrier between the two fluid streams in the heat exchanger
- The tube plate is a heat transfer surface itself
- structural component that helps maintain the overall integrity and strength of the heat exchanger
TUBE PLATE
- provides a path for this condensed liquid to exit the heat exchanger
- ensures that the liquid is continuously drained, preventing such accumulation
- helps maintain the thermal efficiency of the heat exchanger
- typically connected to a drainage system that collects and disposes of the condensed liquid
CONDENSATE OUTLET
- help dampen vibrations, preventing damage to the tubes and potential tube-to-tube or tube-to-shell contact
- help maintain the proper alignment and spacing of the tubes within the heat exchanger
- provide the necessary support to prevent excessive sagging and maintain tube integrity
- help distribute these stresses evenly across the tubes and prevent localized stress concentrations, which can lead to tube failure
- make it easier to remove and reinsert tubes when necessary
TUBE SUPPORT
- typically used in applications where the temperature of the fluid inside the tubes changes, causing the tubes to expand or contract
- help to reduce thermal stress on the heat exchanger tubes
- provide support for the tube bundle inside the shell of the heat exchanger
- used in heat exchangers to create a more compact design compared to straight tube arrangements.
- serves the purpose of transferring heat from one fluid to another
- used to cool or heat another fluid, depending on the temperature difference between the two fluids
- used to absorb heat and change from a liquid to a vapor, which is often seen in cooling towers or distillation columns
- used to recover waste heat from one process and transfer it to another, improving energy efficiency
- facilitate the integration of different processes or systems by transferring heat between them, helping to optimize energy usage and reduce energy costs
U-TUBE
- serves as the outer container or housing that encases the heat exchange process
- It encloses the tubes or other heat transfer surfaces where the hot and cold fluids flow
- designed to withstand the pressure of the fluids inside, ensuring that the heat exchanger can operate safely under the specified conditions
- minimize heat loss to the surrounding environment
- provides support and alignment for the tube bundle, ensuring that the tubes are properly positioned for efficient heat transfer
- designed with access points such as manholes, nozzles, and connections to allow for inspection, cleaning, and maintenance of the internal components, including the tube bundle and heat transfer surfaces
SHELL
- refers to the fluid or substance that flows out of the heat exchanger at the bottom of one of the two interconnected channels or compartments
- carry the thermal energy (heat) gained or lost in the heat exchange process to be used in a subsequent process or to maintain the desired temperature of a system
BOTTOM PRODUCT
- serves the purpose of transferring heat from one fluid to another
- used to cool or heat another fluid, depending on the temperature difference between the two fluids
- used to absorb heat and change from a liquid to a vapor, which is often seen in cooling towers or distillation columns
- used to recover waste heat from one process and transfer it to another, improving energy efficiency
- facilitate the integration of different processes or systems by transferring heat between them, helping to optimize energy usage and reduce energy costs
LIQUID FEED
- a piece of ship’s equipment used to produce fresh drinking water from sea water by distillation
- a unit operation that is typically used to concentrate a solution by evaporating some of the solvent
- Is installed in the engine room utilizing the heat available from the main engine jacket cooling water system to produce fresh water for use on-board the vessel.
EVAPORATOR
Sea water contains soluble salts of calcium and magnesium, which on boiling change to insoluble salts and get deposited as a crust on the inner sides of a boiler.
CALCIUM AND MAGNESIUM
the unit consists of a tubular heat exchanger that is fitted inside the casing at the base of the evaporator.
HEATER SECTION
maintains the correct brine level by removing excess brine. The brine ejector also removes the gases liberated from the sea water when it is heated and so the vacuum is maintained.
EVAPORATOR VESSEL
- is a tubular unit through which sea water flows from the duty main cooling sea water pump.
CONDENSER SECTION
- uses sea water as its driving medium and extracts brine and incondensable gases from the evaporator.
AIR EJECTOR
- is a single-stage centrifugal pump that supplies the brine/air ejector with operating water
EJECTOR PUMP
- continuously checks the quality and salinity of the fresh water produced and notifies the duty engineer if the salinity has exceeded a pre- defined set point of 10ppm
SALINOMETER
contains motor starters, running lights and contacts for the remote alarms.
CONTROL PANEL
- The unit is operated by a Iwaki type EH-R electromagnetic pump and the injection of treatment chemical is intended to inhibit foaming and control the formation of scale on the heating surfaces thereby allowing prolonged operation without the need for a plant shutdown for cleaning
CHEMICAL INJECTION UNIT
production of pure water from seawater by evaporation and re-condensing. Distilled water is produced as a result of evaporating sea water either by boiling or a flash process
Marine Distillation Process
______ is boiled using energy from a heating coil, and by reducing the pressure in the evaporator shell, boiling can take place at about _____°C. The seawater from the ship’s services is first circulated through the condenser and then part of the outlet is provided as feed to the evaporation chamber.
SEA WATERR AND 60C
is the result of a liquid containing a reasonable amount of sensible heat at a particular pressure being admitted to a chamber at a lower pressure. The liquid immediately changes into steam, i.e. it flashes, without boiling taking place.
FLASH EVAPORATION
the high pressure deaerated water supplied to the boiler from which steam is generated.
FEED WATER
partially or completely remove vapor/liquid. In case of _______ water, the steam was removed or completely liquefied into a liquid form through deaerator
DEAERATED
