This type is especially applicable for vacuum condensers, and can be equipped with integral finned tubes to counteract the effect of low shellside velocity on heat transfer. The exhaust pressure in the condenser is maintaned. Compress pdf files for publishing on web pages, sharing in social networks or sending by email. Plate condensers are used mainly for smaller power plants. Air cooled steam condensers air cooled condensers types natural convection. An assessment of the use of direct contact condensers. The dewar condenser is a special type of condenser meant to be used with special types of coolants, in order to reach very low temperatures. The steam condenser receives the exhaust steam from one end and comes in contact with the cooling water circulated within it form the cooling tower. R sekulib university of kentucky introduction a heat exchanger is a device that is used for transfer of thermal energy enthalpy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a. It is a device or an appliance in which steam condenses and heat released by steam is absorbed by water. Steam gets condensed while it comes in contact with the falling water. Particularly with steam, it depends upon the method used to generate such as coal, oil, gas and electricity. Both of these steam turbine types have their own operating schemes and benefits which are described here in detail. Occurs when an outer force pushes a fluid, such the same as water of air, to create it move about and transfer heat.
Another type, which is produced in large quantities, a scroll compressor, but still these compressors are not available in the amount normally encountered in industrial refrigeration. Surface condensers are basically a shell and tube heat exchanger consisting of water boxes for directing the flow of cooling water to and from horizontal tubes. Cooling water is distributed inside the condenser in the form of a fine spray that contacts and condenses the steam. In this article, we will see the difference between difference between condensing turbine and back pressure turbine. In such condenser even impure water can be used for cooling purpose whereas the cooling water must be pure in jet condensers. The steam turbine is one kind of heat engine machine in which steams heat energy is converted to mechanical work. Design of vacuum systems for crude oil vacuum tower. In the world of hvac, condensers happen to be a topic of great importance. The main purpose of a steam condenser in turbine is to maintain a low back pressure on the exhaust side of the steam turbine after releasing from nozzles, the steam has to expand to a great extent for converting available energy into it to usable mechanical work. Condensers 1674 condensors are used to liquify vapors. A surface condenser is a commonly used term for a watercooled shell and tube heat exchanger installed to condense exhaust steam from a steam turbine in thermal power stations.
Horizontal condensation on the outside of the tubes 2. Thesis performance of an aircooled steam condenser. In the efficient use of energy second edition, 1982. We define the evaporation process as one that starts with a liquid. It consists of a rotor and a set of rotating blades which are attached to a shaft and the shaft is placed in the middle of the rotor. Direct aircooled condenser units in power plants usually consist of finned tubes arranged in the form of a delta or aframe to drain condensate effectively, reduce distribution steam duct lengths. It is connected to the air extraction pump and condensate extraction pump. Boiling water sensible steam heat latent heat temperature change measurable tt change the water to steam. The pressure of outlet steam depends on in the load, therefore, this turbine is also known as the backpressure steam turbine. Types of steam turbine an overview sciencedirect topics. When a j type shell would still produce too high a pressure drop, an x type shell, shown in fig. Steam turbines may be classified into different categories depending on their construction, working pressures, size and many other parameters. The condenser uses cooling water to remove the steam s latent heat and convert the steam to condensate.
Difference between condensing turbine and back pressure. As the low pressure steam comes in contact with the cooling water, it condenses and converts into water. It is also selected when no high pressure steam is available. Steam condenser definition, working, types and advantages. Thus, the condensing temperature is a function of the ambient air drybulb temperature. In the condenser, cooling water condenses the steam voc mixture. Many translated example sentences containing gland steam condenser germanenglish dictionary and search engine for german translations. Steam condensation analysis in a power plant condenser. Water runs through the coil, and refrigerant vapor is discharged from the compressor, condensing on the outside of the cold tubes. This steam then leaves the turbine at the atmospheric pressure or lower pressure. Condensation can be done by removing heat from exhaust steam using circulating cooling water. Performance characteristics of an aircooled steam condenser incorporating a hybrid drywet dephlegmator johan adam heyns dissertation presented in partial fulfilment of the requirements for the degree master of engineering at the university of stellenbosch thesis supervisor.
To maintain condensate separate from the cooling water, a bank of plate heat exchangers is used. Wit solapur professional learning community 1,461 views. Surface condensers can be classified into varies types depending upon the position of condensate extraction pump, flow of condensate and arrangement of tubes. Pdf power plant lecture notes chapter2 steam power. Jet condensers can be classified into three types and are discussed below with schematic diagrams of each condenser type. Cooling medium is used water to convert steam into water. There are 3 condensers used in hvac systems watercooled aircooled evaporative applications air cooled if the condenser. Steam condenser steam condenser objective type questions and answers.
Rotary vane compressors are still used as a low stage compressors, but very little installed. The function of a surface condenser is to create the lowest possible turbine or process operating back pressure while condensing steam. Condenser pressure depends on coolingwater temperature, which, under normal. The steam condenser, shown in figure 9 below, is a major component of the steam cycle in power generation facilities. Unlike other services this tool doesnt change the dpi, thus keeping your documents printable and zoomable. Steam flow distribution in aircooled steam condenser for. Instead of confusing information, my goal is to provide you with some basic information on the different types of condensers and their applications. Practically, yes, but technically speaking a condenser is not a heat exchanger. If part of the voc is immiscible in water, the condensate can be sent to a.
Most industrial installations are in the range 15 mw e. Power plant condenser fouling dew speciality chemicals. Plate types consisting of a series of parallel plates that provide paths for the steam and the cooling water. The noncondensing steam turbine uses highpressure steam for the rotation of blades. Prior to supplying steam to the turbine, the steam supply pipelines have to be drained and heated up. These are manufactured for outputs from 50 kw e to 30 mw e. It consists of a copper coil located in a steel shell. In a case study for a nominal1 30mwe steam power plant, two. As the lowpressure steam comes in contact with the cooling water, it condenses and turns into water. Purpose of a condensor and its different types bright. Condensers are delivered as fully tubed modules, so that little welding is required on site. Steam turbine working principle and types of steam turbine. Firstly, a condenser is an apparatus that is used to convert vapour into a liquid state.
Water demand from thermal power plants, mainly for steam condensation power plant cooling can place a significant burden on limited local and regional freshwater supplies. In jet condensers there is direct contact between the exhaust steam and cooling water. Jet condenser low level high level ejector jet condenser. Large steam system condensers heat exchanger engineers. The advantage of central flow type su rface condenser over the down flow type is that the steam flows over the whole periphery of the water tubes as the steam flows radially inwards. Power plant lecture notes chapter2 steam power plant cycles. Technological investigations and efficiency analysis of a steam heat. Direct contact condensers condense the turbine exhaust steam by mixing it directly with cooling water. The exhaust steam and water come in direct contact with each other and temperature of the condensate is the same as that of cooling water leaving the condenser. In surface condensers, there is no direct contact between the exhaust steam and the cooling water. This model makes possible calculations of steam con densation mixed with air as a noncondensing gases ncgs which resists heat transfer.
In this article, you will learn what is steam condenser and its working principle, advantages and types of steam condenser with pdf. The figure above shows the longitudinal section of a two pass surface condenser. The obvious advantage of aircooled condensers relative to watercooled condensers is that cooling water is not needed. There is no piston rod,flywheel or slide valves attached to the turbine.
An approach to reducing this cooling water demand is the use of direct dry. Condensing turbine is selected when the steam demand for the process drivers is greater than the lowpressure process steam requirements. It is a closed space into which the steam exits the turbine and is forced to give up its latent heat of vaporization. These condensers are heat exchangers which convert steam from its gaseous to its liquid state at a pressure below atmospheric pressure. Down flow type condenser sectional view is shown in fig. Evaporation is an operation used to remove a liquid from a solution, suspension, or emulsion by boiling off some of the liquid. In condensers the refrigerant gives up the heat that is has absorbed in the evaporator. On the other hand, the heat exchanger is used to recover. In aircooled condensers, condenser heat is rejected directly to the ambient air. Occurs when a heater with a reduction of dense fluid is pressed left by a cooler denser fluid. And because of this, the whole condensate can be used as boiler feed water. An introduction to condensers and auxiliary equipment for.
Although the capital cost and the space needed is more in surface condensers but it is justified by the saving in. An introduction to condensers and auxiliary equipment for steam. The main function of condenser is to convert gaseous form of exhaust steam into liquid form at a pressure of below atmosphere. Ideally, when steam leaves the turbine of a condenser, it has used all of its available heat for work and is saturated. In down flow condensers exhaust steam enters at the top and flows downward. Performance characteristics of an aircooled condenser. Formula for solving steam condenser numericals steam condenser. In surface condensers there is no direct contact between the steam and cooling water and the condensate can be reused in the boiler. Extraction condensing steam turbine the extraction turbine. Common practice has the vacuum condenser specified as just another heat exchanger. The function of a condenser in a thermal power plant is a. A compact condensing unit is created by placing the compressor inside the condenser. Lab manual to study about various types of steam condensers. Surface condenser is a type of steam condenser in which the steam and cooling water do not mix with each other.
Main types of compressors used in industrial refrigeration are screw, piston, centrifugal and rotary vane. Steam condenser and its types from university syllabus point of view. The steam condensers are broadly classified into two types. It is thus a thermal separation, or thermal concentration, process. Where cooling water is in short supply, an aircooled condenser is often used. Steam condenser is a device in which the exhaust steam from steam turbine is condensed by means of cooling water. The steam condenser receives exhaust steam from one end and gets in contact with the cooling water flowed within it form the cooling tower. Aircooled condenser an overview sciencedirect topics.
Instead of having the coolant circulating in it, it has a container where one can put the coolant mostly solid coolants are used. In case of turbines with cooling water preheating and lowpressure lp bypass, prior to supplying steam the regeneration and dumping systems have to be. Spray condensers utilize mixing or direct contact of cooling water and steam. Here condenser chamber is placed at low elevation and overall height of the unit is low enough so that the condenser may be directly placed beneath the steam turbine, pump or pumps are required to extract the cooling water condensate and air from the condenser. Steam condenser steam condenser objective type questions. The water flows in downward direction through a series of perforated trays. Select pdf files from your computer or drag them to the drop area. All steam turbines can be classified into two categories. Understanding process vacuum condensers process vacuum condensers are an integral part of a vacuum system so often, a process vacuum condenser is considered standalone equipment, with little consideration given to how best to integrate it into a vacuum system. Heat exchanger knowledge heat exchanger companies suppliers. Energy costs for the utilities to operate an ejector condenser unit varies widely from one part of the country to the other.
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