Ejectors and steam jet ejectors document library graham. They are especially effective in the chemical industry where an onsite supply of the highpressure motive gas is available. These jackets must be provided with a continuous flow of lowpressure. In multistage ejectors, it is usually advantageous to condense the steam from each stage in a watercooled intercondenser so as to reduce the load to the succeeding stage.
S a k jeelani,k v kasipathi rao, g r balasubramanian designing steam jet ejectors chemical engineering april 9 1979 7. Ejector design software ejector sizing calculation. Steam ejectors use steam or gas instead of moving parts to compress a gas. Design features and operation of jet ejectors korting hannover ag. In this example two jet ejector stages are connected in series to achieve a suction pressure of 1 mbar with a minimum of motive medium. When first developed, its operation was intriguing because it seemed paradoxical, almost like perpetual motion, but it was later explained using thermodynamics. Multistage steam jet vacuum systems korting hannover ag. The steam entrains the suction gases and the mixture. Leading manufacturer of eductors and ejectors in chennai, india. The eductor is a liquidliquid ejector, which used pressurized water for pumping other liquid from a lower to another higher level. As a first estimate, a five stage ejector is assumed. If you can then use the typical steam jet ejector, the second article tells. Steam jet ejectors bulletin 5eh singlestage ejectors fig. Steam ejector calculations free download as excel spreadsheet.
The steam jet refrigeration system also known as ejector system refrigeration system is one of the oldest methods of producing refrigeration effect. Product catalog gea engineering for a better world. We also lead the industry in the duplication of parts and assemblies for rotating equipment such as steam turbines, compressors and more. The unit is available in standard sizes up to 6 and custom fabricated for larger sizes. Best a generalized ejector model was successfully developed for gas ejector design and performance analysis. The steam ejector is a simple device consisting of three basic components, a motive steam nozzle, a suction chamber and a mixing diffuser. Graham corporation ejector troubleshooting youtube. Insulate lines, trap low spots, set line sizes for 150ftsec. In 1910, leblanc introduced a cycle having a vapor jet ejector. Hence it is relatively lowcost and easy to operate and maintenance free equipment. In a jet or ejector, a relatively highpressure gas, like steam or air, expands through a nozzle.
Jet pumps, also referred to as ejectors, are devices for the conveyance, compression or mixing of gases, vapors, liquids or solids in. Ejector design software to do conceptual design and generate ejector sizes. The efficiency of the ejector cycle is very sensitive to the ejector efficiency. Very often, the motive fluid is steam and the device is called a steam jet ejector. Steam jet ejectors the largest vacuum producing devices available are used in the most demanding of applications. His setup allowed producing a refrigeration effect by utilizing lowgrade energy. The system comprises a closed seal tank called buffer. Review of ejector design parameters and geometry for refrigeration and. Use steam jet ejectors or thermocompressors to reduce venting. Steam jet ejector free download as powerpoint presentation.
Steam jet refrigeration system seminar report download. Product catalog jet pumps mixers, heaters vacuum systems. The terms of jet pumps ejectors are defined in din 24290. An experimental investigation of steam ejector refrigeration. The new standard now integrates the previous three separate standards on steam jet ejectors.
These systems operate on the ejector venturi principle, which relies on the momentum of a highvelocity jet of steam to move air and other gases from a connecting pipe or vessel. Steam jet heaters h for passage and circulation heating systems 99 aw5. Steam jet ejectors for vacuum duty or vapor recompression represent only one area of ejector application. A steam injector is typically used to deliver cold water to a boiler against its own pressure, using its own live or exhaust steam, replacing any mechanical pump. In operation, steam issuing through an expanding nozzle has its pressure energy converted to. The function depends, above all, on the design of the. Allows the use of all types of liquids or solutiosn, provided that there is no impediment to mix them. The basic operating principle of an ejector is to convert the pressure into speed.
Steam jet air ejectors have a low initial cost, so are an economical means and reliable equipment for producing a vacuum. Cfd simulation of ejector in steam jet refrigeration. Steam ejector design chemical process engineering engtips. Combined vapour compressionejector refrigeration system. Other types of injector may use other pressurised motive fluids such as air. Pdf experimental investigation of steam ejector system. Designing air jet ejectors chemical engineering september 25 1976 p5 6. Performance optimization of steam jet ejector using cfd.
Exhaustive survey has been conducted on the influence of geometrical parameters on the efficiency of the ejector as well as critical flow parameters to improve the overall performance. The motive steam enters the ejector through the motive fluid nozzle and is expanded into the mixing diffuser converting pressure energy into velocity energy. The steam or air converts that pressure or potential energy to velocity or kinetic energy. Since 1936 graham corporation has been supporting our customers around the globe with heat exchangers, water heaters, steam surface condensers, steam jet ejectors steam. An ejector is a device used to suck the gas or vapour from the desired vessel or system. This basic principle applies to every jet ejector in different models and ranges of application. Producing a vacuum with steam jet ejectors in a vacuum jet ejector, the lowpressure vent steam is the motive energy source. The suitability of vacuum pump or steam jet air ejector systems for a given application depends on the availability of motive steam during startup, the costs associated with the usage of steam or electricity and the preferences of the end user. Multistage, steam jet vacuum systems, surface condenser. A steam jet ejector is illustrated below as ex ample steam serves as motive fluid to create vacuum. Steam jet ejectors are based on the ejectorventuri principle.
Both the motive vent steam and the suction vaporsgases pass through a venturi throat and are released through a diffuser. Ejector working principle mechanical engineering site. Dry steam is supplied to the probe and then ejected through a jet situated in the mouth of a venturi. Above a critical pressure ratio between primary and secondary around 1. The definitions of overall ejector efficiency and ejector component efficiencies in literature are. These power systems have found wide acceptance in modern plants because of the small space requirements, simplicity, reliability, low maintenance and quick starting characteristics. However, for higher pressure ratios, compressibility effects need to be taken into account. An ejector is essentially a fluidfluid pump that has no pistons, valves, rotors, or other moving parts and works by transfer of momentum from the primary fluid high pressure to the secondary fluid aspirated low pressure. Ejectors are remarkably simple yet extremely useful devices. Scribd is the worlds largest social reading and publishing site. The figure on the right illustrates a 3stage system. In a steamjet ejector, the suction chamber is connected to the vessel or pipeline that.
Pdf geometrical optimization of a steam jetejector using the. The basic components of this system are an evaporator, a compressor device, a condenser and a refrigerant control device. Review on ejector efficiencies in various ejector systems. The ejector design principles used in the ejector calculations for the program are explained including the ejector energy balance and effects of the ejector flow cones free demo programs for a short time are offered to let you see how the ejector program works they are not. The two major functions of ejectors are as follows.
Working principle of steam ejector power plant tutorials. If the objective is to pull a vacuum on a process vessel, the device is called an ejector. Equivalent suction flows for steam jet vacuum pumps. Steam ejector design pdf schutte koerting has a century of experience in designing and building efficient jet vacuum ejectors. For small pressure differences, gasgas ejectors can be treated like liquid jet pumps.
Ejector modeling and examining of possibility of replacing. Steam jet vacuum systems combine ejectors, condensers and interconnecting piping to provide relatively lowcost and lowmaintenance vacuum pumping. Unique systems designs and manufactures process vacuum systems including condensers, steam jet ejectors, liquid ring vacuum pumps and hybrids along with instrumentation, complete automation and auxiliary equipment. Pdf cfd simulation of ejector in steam jet refrigeration. Vacuum products steam jet ejectors by graham corporation.
Since steam was widely available at that time, the socalled steam jet refrigeration systems became. The ejector diffusers of the first two stages of a fivestage system and the first stage of a fourstage system are furnished with a steam jacket to prevent freezing in the diffuser. The ejector design has basic advantages such as absence of moving parts and simplicity of operation. They require almost no maintenance for long periods. When a high pressure motive fluid steam liquid enters the steam nozzle, this result in a decreasing pressure and increasing velocity of the fluid again the fluid enters in the diffuser which result in a increasing pressure and decreasing velocity of the fluid so due to pressure difference vacuum is created in between the nozzle and diffuser we can say venture.
The number of booster ejectors 1, 2 or 3stage before the first intermediate condenser depends on the process vacuum required, the cooling water conditions. Relative suction flow of steam jet vacuum ejectors the result of calculation will be identical with the download fulltext pdf. A steam jet ejector is illustrated below as example steam serves as motive fluid to create vacuum. An ejector is similar to an of vacuum pump or compressor. Ejector thermocompressor equirepsa vaccum production.
First, equal steam flow rate is assumed to each stage. Previous 1d analytical models can be derived from this new. This reduces the size and steam consumption of the succeeding stages and results in a reprinted from petroleum refiner, december 1958 1 ejectors ejectors are simple pieces of. Specialize in design, manufacturing, testing and supply of portable ejectors, bilge ballast cargo ejectors, liquid jet ejectors, air ejectors, acidalkali dilution ejectors, liquid jet exhausters, venturi scrubbers, tank mixer eductors, steam jet heaters, solid conveying eductors. The steam jet exhauster or vacuum pump is gas jet gas pump and is the basic stage for all high vacuum equipment. Case study steam jet ejector free download as powerpoint presentation. The thermocompressor is a steam jet steam compressor, shown with a diaphragmoperated spindle for control purposes. The steam jet blower is a steam jet or air jet air pump designed for large capacities at low drafts.
Multistage steam jet vacuum systems operating in alkaline. The application determines the design of the flow section. The attached figures illustrate the two types of steam jet air ejector sjae systems used in the industry to remove noncondensables and water vapor from main condensers. The familiar water jet pump found in chemistry laboratories is, in essence, an ejector that uses water as the motive fluid. Basic ejector components are the steam chest, nozzle, suction, throat, diffuser and they discharge fig. The overall compression ratio required is approximately 55. Liquid jet ejector motive medium contributing to designation. Air andor water vapor are sucked from the process into the mixing chamber at nearvacuum conditions. The attached article has a equation english units as given in the standards for steam jet vacuum systems published by heat exchange institute hei. Ejector design calculation pdf download anpsortigas. Wet steam install a separator and trap at ejector system. A jet ejector requires no mechanical drive and has no moving parts. The major difference between the ejector and the vacuum pump or compressor is it had no moving parts. Pdf the vacuum systems play crucial role in various industries including, but not limited to, power generation, refrigeration, desalination, and.
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