Then, the compressed vapor is condensed, and its latent heat is transferred to the feed seawater. Lara and others published advanced mechanical vaporcompression desalination system find, read and cite all the research you need on researchgate. Vaporcompression evaporation is the evaporation method by which a blower, compressor or jet ejector is used to compress, and thus, increase the pressure of the vapor produced. Technology and applications gea engineering for a better. The vapor compression devices include mechanical compressors, steam jet ejectors which is known as thermal vapor compression, adsorptiondesorption beds, and absorptiondesorption columns. Mechanical vapor recompression evaporators swenson. Installation for the encon mvc evaporator is very straight forward and is generally handled by facilities, maintenance, or plant engineering personnel.
The vapor compression refrigeration system you need to know some basic rules of physics to understand the vapor compression cycle. Both a steadystate and a transient simulation will be considered. Fundamentals of mechanical refrigeration systems course content introduction mechanical refrigeration is a thermodynamic process of removing heat from a lower temperature heat source or substance and transferring it to a higher temperature heat sink. In this study, experiments have been performed on a mechanical vapor compression desalination system mvc. Us6375803b1 mechanical vapor recompression separation. The actual vapour compression cycle differs from the standard cycle due to the following reasons. Environmental impact cost analysis of multistage flash. Vapor compression refrigeration system basic, working.
Vapor compression refrigeration system basic, working, parts of system introduction. Vaporcompression refrigeration, in which the refrigerant undergoes phase changes, is one of the many refrigeration cycles and is the most widely used method for airconditioning of buildings and automobiles. In this study, md is used to replace the preheater heat exchanger used for thermal energy recovery from the brine stream in mechanical vapor compression mvc. This vapour compression system mainly consists of a refrigerator compressor, a liquid compressor, a liquid receiver, a refrigerant control valve also called as an expansion valve and evaporator vapour absorption refrigeration system. Vapour compression refrigeration or vapor compression refrigeration system vcrs, in which the refrigerant undergoes phase changes, is one of the many refrigeration cycles and is the most widely used method for airconditioning of buildings and automobiles.
Mechanical vapor compression in mechanical vapor compression, positive displacement compressors or multi stage centrifugal compressors are generally used to raise the pressure and temperature of the generated vapors. To reduce energy consumption, water vapor from an evaporator is entrained and compressed with high pressure steam in a thermocompressor so it can be condensed in the evaporator heat exchanger. It achieves its high efficiency in a simple manner, producing a high quality distillate. It also includes the process of maintaining and reducing the temperature of a body below the general temperature of its surroundings. In the following years, its areas of application were expanded, and now include the dairy industry, brewing industry, sugar industry, saline industry, pulp industry, chemical industry, alcohol industry etc. Mechanical vapor compression evaporator mvc by encon. Vapor compression refrigeration, in which the refrigerant undergoes phase changes, is one of the many refrigeration cycles and is the most widely used method for airconditioning of buildings and automobiles. It is basically a heat pump process that pumps heat from a lowtemperature reservoir to a higher temperature reservoir, just.
The mechanical vapor compression mvc desalination system is based on distillation of seawater. Reactors department, nuclear research center, atomic energy. Simultaneously, other plant operations may require intermediatepressure steam at 20 to 50 pounds per square inch gauge psig. Mechanical vapor compression mvc arab journal of nuclear. From 2 the high pressure high temperature vapour is first sensibly cooled to saturation, then condensed and ultimately sub.
The mechanical vapor compression mvc desalination technology offers an interesting alternative for smallscale desalination of seawater to produce high quality distilled water with competitive cost. System pressure boosting vapor recompression can be used in steam distribution systems to boost system pressures that have dropped to unacceptably low levels. The encon mvc evaporator is a forced circulation flash evaporator utilizing mechanical vapor compression. Mechanical vapor compression evaporator mvc by encon evaporators. The mechanical vapor compression mvc is among the most efficient distillation processes. Swenson thermal vapor recompression tvr evaporators use a thermocompressor to reduce the steam required per pound of evaporation. Difference between vapour compression and vapour absorption pdf. The system is quiet in operation due to less number of moving parts. A method and apparatus for removing a contaminant from a fluid feed stream containing the contaminant. The mechanical vapor compression process is a highly energy efficient and cost effective way of retaining and reusing the latent heat contained in. Mechanical vapour recompressors mvr with the increased need of energy steam conservation the subject of mechanical vapor recompressor has picked up great pace over the last few years. Incro water is therefore said to be the great source of making a water pure by doing the purification processes.
Since 1969 with the installation of ides first commercial mvc plant, circa of 260 units have been installed worldwide in single and multi. Analysis of a mechanical vapor compression desalination system. Thermal vapor recompression tvr evaporator swenson. Mvc evaporators installation mechanical vapor compression. Sep 20, 2011 meco was founded in 1928 as mechanical equipment company, inc. Today we will study the difference between vapour compression and vapour absorption refrigeration system in detail.
Energy in the form of heat is required to change a substance from a liquid to gas i. Thermal vapor compression in thermal vapor recompression steam jet ejectors are used to raise the pressure and temperature of the gener ated vapors. Technology and applications gea engineering for a better world. The heat required to evaporate water which flows on one side of a heat transfer surface is supplied through the simultaneous condensation of the distillateproducing vapor on. Comparison of vapor absorption system with vapor compression. Refrigeration may be defined as a process of removing heat from a substance and pumping it to the surroundings. Solar energy can be used to desalinate water directly in solar stills or used as an energy source for other thermal processes. Contents processes designed to save energy in evaporation plants 3 types of construction of mechanical vapour recompressors 7 principles of function and design features 10. Use vapor recompression to recover lowpressure waste steam lowpressure steam exhaust from industrial operations such as evaporators or cookers is usually vented to the atmosphere or condensed in a cooling tower. To reduce energy consumption, water vapor from an evaporator is entrained and compressed with high pressure steam in a thermocompressor so it can be condensed in the. Advanced wastewater treatment technology mechanical vapor. It is sometimes economical to compress vapor from the last effect of a double or tripleeffect evaporator so that the vapor can be condensed in the firsteffect heat exchanger. On certain days when the sun shines a little too brightly and the warmth becomes unbearable people often find themselves turning up the air conditioning in order to feel just a little cooler.
Pdf advanced mechanical vaporcompression desalination system. Pdf performance evaluation of a mechanical vapor compression. Mechanical vapor compression is a modern method that produces potable water at acceptable energy efficiency 1. Vapor compression system takes in high grade such as electrical or mechanical energy for its operation of compressor used in the cycle. Refrigerant r22 vapour enters a positive displacement compressor at a slightly superheated state 1 and is then compressed to state 2. Vapor from an evaporator is compressed with a positivedisplacement, centrifugal or axialflow compressor to a higher pressure so that it can be. The only energy required to pump the heat content in the vapor from the evaporation side to the condensation side of the heat transfer surface is the mechanical energy required to drive the compressor. Us10399003b2 mechanical vapor compression desalination. Aquaswiss mechanical vapor compression mvc distillation is the most thermodynamically efficient process of singlepurpose thermal desalination. Global optimal design of mechanical vapor compression mvc desalination process marian marcovecchioa, pio aguirrea, nicolas scennaa, sergio mussatia. Further heating the feed stream in a second heating step 20 in a. Whereas the vcr system needs work energy to produce cold which is a high.
Mechanical vapor compression an overview sciencedirect topics. Use vapor recompression to recover lowpressure waste. Seawater is sprayed outside of the heated tube bundle where it boils and partially evaporates, producing more water. Mechanical vapour recompression reduces the energy costs and the co 2oot f print and, consequently the environmental load. Mechanical vapor compression mvc evaporator the encon mvc evaporator is a forced circulation flash evaporator utilizing mechanical vapor compression. The mechanical vapor compression mvc distillation is inherently the most thermodynamically efficient process of singlepurpose thermal desalination plants. Mechanical vapor compression an overview sciencedirect. The vapor compression can be done by ther mal vapor compression or mechanical vapor compression process. Meco was founded in 1928 as mechanical equipment company, inc. Pdf advanced mechanical vaporcompression desalination. System description the layout of the system is shown in figure 1.
Analysis of a mechanical vapour compression desalination. Because the most critical cost parameters are the fixed. Mechanical vapor recompression blower and compressor. P coefficient of performance and vapour absorption has low c. Figure 1 shows the advanced mechanical vapor compression desalination system. Use vapor recompression to recover lowpressure waste steam. The system is basically a heat exchanger that is an evaporatorcondenser. The system has more weak, tear and noise due to moving parts in the compressor. A steam jet ejector is used to raise the temperature and pressure of vapors generated from the first effect of. Lara and others published advanced mechanical vaporcompression desalination system find, read and cite all the. Process description mechanical vapor compression distillation of saline water is a process in which mechanical energy is used as the main driving force. This paper presents an economical and thermal study of single.
According to one aspect of the present invention, there is provided a method of removing contaminants from a fluid feed stream containing solid and liquid contaminants by mechanical vapor recompression employing a heated separator, heat exchanger and compressor, the method comprising the steps of. Mechanical vapor compression desalination system download pdf info publication number us10399003b2. In this in this example, three evaporator stages are illustrated, but fewer or more could be employed. The method includes the steps of providing a feed stream 10 and heating it in a first step 18 to at least partially remove some of the contaminants and recover energy from a concentrate and distillate generated.
Mvc evaporator surface footprint process description. Everest is the only company in india to offer mvr blowers with a successful track record of over 10 years. It is also used in domestic and commercial refrigerators, largescale warehouses for. The red sea area winddriven mechanical vapor compression desalination system. Layout of the r22 vapourcompression refrigeration system. Vapor compression distillation pharma vapor compressions. Vapourcompression refrigeration or vaporcompression refrigeration system vcrs, in which the refrigerant undergoes phase changes, is one of the many refrigeration cycles and is the most widely used method for airconditioning of buildings and automobiles. Analysis of a mechanical vapor compression desalination. The main differences between vapour compression and vapour absorption refrigeration system are vapor compression has high c. Md systems with internal heat regeneration have been compared to and modeled similar to counterflow heat exchangers. The water vapor can be compressed in one of two ways. The use of mechanical vapor compression plant to reduce. A singleeffect mechanical vaporcompression system is to be designed at the following conditions. In the vapor absorption process, the compression process of the vapor compression cycle is replaced by an absorber, a generator and a pump.
Mechanical vapor compression heat pumps geothermal heat. Layout of the r22 vapour compression refrigeration system. The encon mvc evaporator product line has standard offerings that range in capacity from 404,000 gallonshour. The mechanical compressor creates a vacuum in the vessel and then compresses the vapor taken from the vessel and condenses it inside a tube bundle. Ganesan, kumar, clark, casey, kannawin, jon, webb, justin, gillespie, karen, moon. Research questions this research is guided by the following questions. It achieves its high efficiency in a simple manner, producing a high. Method of analysis the mass, species, energy, and exergy accounting equations are solved for each of the process subsystems. It is also used in domestic and commercial refrigerators, largescale warehouses for chilled or.
Final report use of mechanical vapor compression mvc. Hot, deaerated feed enters the evaporator sump, where it combines with recirculating brine slurry. If compression is performed by a mechanically driven compressor or blower, this evaporation process is usually referred to as mvr mechanical vapor recompression. Mechanical vapor compression mechanical vapor compression is very suitable for the recovery of high quality water.
The distillate flow rate, m d 1 kgs the heat capacity of the vapor is constant, c p v 1. A singleeffect mechanical vapor compression system is to be designed at the following conditions. Mechanical vapor compression aquaswiss ag the thermal. In the vc process, the vapor produced by evaporating the water is compressed to increase the saturation pressure and temperature. This vapour compression system mainly consists of a refrigerator compressor, a liquid compressor, a liquid receiver, a refrigerant control valve also called as an expansion valve and evaporator. Mechanical recompression is not limited to singleeffect evaporation. Thermal vapor recompression tvr evaporator swenson thermal vapor recompression tvr evaporators use a thermocompressor to reduce the steam required per pound of evaporation. Mechanical vapor compressiomembrane distillation hybrids. Increasing energy costs have justified the increased use of mechanical recompression evaporators. In case of compression performed by high pressure motive steam ejectors, the process is usually called thermocompression or steam compression. Use of mechanical vapor compression mvc system for development of water resources in rural areas of developing countries epa grant number. Dynamic performance of a mechanical vapor compression mvc. The heat capacity of all liquid streams is constant, c p 4. In the mvc process, produced water is pumped to a heat exchanger that raises its temperature to a boiling point.
Pdf global optimal design of mechanical vapor compression. Figure 1 shows a general simplified flow diagram of a basic mechanical vapor compression distillation system. However, compared to other major desalination technologies such as reverse osmosis, mechanical vapor compression has had relatively high operating and capital costs. Howden is the one company who offers all of the primary rotating machinery types commonly used for mvr vapor compressor applications, and thus the widest product range. Mechanical vapor compression systems operating in a subcritical cycle represent the vast majority of heat pump, airconditioning, and refrigeration applications today. This manual method of collecting condensate was more. It is also used in domestic and commercial refrigerators, largescale warehouses for chilled or frozen storage of foods and meats. The numerical modeling is applied to analyze the thermal and. Vapor absorption refrigeration cycle or vapor absorption refrigeration systemvars pdf. Comparison of lobetype and centrifugal compressors appendix glossary bibliography and suggestions for further study 1.
Vapor compressor technologies products and services howden. The vapor usually leaves the evaporator is superheated to prevent droplet of liquid within the compressor. Thermal vapor recompression tvr evaporator swenson technology. Howden understands the unique process, aerodynamic, mechanical, and operations requirements of mvr applications, which differ from most any other application for rotating machinery industry, and as such, you can rely on howden to be your trusted adviser to help you secure the optimum mvr vapor compressor solution. Jun 11, 2018 the mechanical vapor compression process is a highly energy efficient and cost effective way of retaining and reusing the latent heat contained in the vapor. Energy in the form of heat is required to change a substance from a. Vapor recompression limits vapor recompression is limited to applications where the compressor inlet pressure is above atmospheric and the compression ratio is less than two per stage. The principle of the system is to make use of two substances that can be separated when heated.
Mar 09, 2016 comparison of vapor absorption system with vapor compression system can be done in 9 aspects, they are energy input, moving part, evaporator pressure, load variation, evaporator exit, coefficient of performance, capacity, refrigerant and lowest temperatures. Vapor absorption system takes in low grade energy such as waste heat from furnace, exhaust team or solar heat for its operations. In 1939, our future became crystal clear with the patent of the vapor compression process for the distillation of water. Vapor compression distillation vc is a process used to produce water for injection wfi on the principle of distillation, where the water is distilled with phase change and entrainment separation. Mechanical vapor compression distillation of saline water is a process in which mechanical energy is used as the main driving force. Mechanical vapor recompression evaporators swenson technology. Depending on the size of the unit, riggers may be needed to unload the evaporation sections and put them into place. Since the pressure increase of the vapor also generates an increase in the condensation temperature, the same vapor can serve as the heating medium for its mother liquid or solution being concentrated, from which the. These systems operate on steam or electricity and compressed air at a. The cycle operates by transfer of heat through a closedloop cycle by compressing, condensing, expanding, and evaporating a refrigerant fluid. Mechanical vapour recompressors mvr everestblowers. The thermodynamic efficiency is derived from the application of the heat pump principle by a large volumetric flow compressor acting as the heat pump. Overcoming this requires a higher compression ratio which increases power consumption.
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