We shall now consider a singleeffect evaporator, working under the same. Further technical developments led to the first wiegand falling film evaporator, built in 1952, which combined these consider. The horizontal tube evaporator figure 2 is the oldest type of chemical evaporator, although other improved types are now more commonly used. The invention of the multiple effect evaporator is generally credited to norbert rillieux. Multiple effect evaporators can remove much larger amounts of solvent than is possible in a single effect. A multipleeffect evaporator, as defined in chemical engineering, is an apparatus for efficiently using the heat from steam to evaporate water. Joye and koko, 1987 for the design of multiple effect evaporator systems with backward feed is simplified and. A multiple effect evaporator consists of a set of single direction evaporators. A multipleeffect evaporator, as defined in chemical engineering, is an. Because the boiling point of water decreases as pressure. Multiple effect evaporator principle vapor produced in one effect evaporator is used as heating medium in next effect evaporator this reduces total energy requirement required t between steamvapor and product is created by progressively decreasing boiling point of the solution in each effect by lowering pressure. Multiple effect evaporator wikipedia a multiple effect evaporator, as defined in chemical engineering, is an apparatus for efficiently using the heat from steam to evaporate water. Mathematical modeling of the multiple effect evaporation mee desalination process has been carried out to determine the effects of the important design and operating variables on the parameters.
Multiple effects, or stages, are now used to minimize the energy input required to evaporate or boil off undesirable water content. If the feed is above the boiling point, some flash evaporation occurs on entry. A multiple effect evaporator uses the water vapor from one effect as the heating medium for the next effect, which operates at a lower boiling point. Multipleeffect evaporators maximize steam economy as vapor generated from one effect is used to drive another. Multiple effect evaporators overview shailvac surat. Falling film evaporators can be operated with small temperature differences between the heating media and the boiling liquid and they also have short product contact time. Design and simulation of a multipleeffect evaporator using.
Multiple effect evaporator evaporation boiling scribd. Sep 16, 2016 in multiple effect evaporator, the pressure in each effect is lower than that of the effect to which it receives steam and higher than that of the effect to which it supplies vapors. The use of this system requires that steam be available at high pressure, and low. Evaporators falling film evaporators manufacturer from meerut. Multiple effect evaporator is the combination of several sets single effect evaporator. In a multiple effect arrangement, the latent heat of the vapor product off of an effect is used to heat the following effect. It is the quantity of vapour produced per unit steam admitted. Carrying an enormous experience of over a decade in designing and manufacturing of multiple effect evaporators, shail vac has emerged as a reliable and trustworthy name in the national and international market. A multiple effect evaporator is design to cut down the steam consumption by different operating strategies like feed, condensate and product flashing, vapor compression, vapor bleeding, feed and steam splitting and using an optimal feed flow sequence.
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. Depending on the final destination of the condensate, it could be directly reused. The advantages of multiple effect systems relative to singleeffect, consist in heating fluid saving, due to a more. This type of multiple effect system is perfect for continuous feed applications, as fluids are progressively reduced in each effect to final concentration discharge.
The horizontal tube evaporator is the only type of chemical evaporator in which the heating medium is inside the tubes. Feeding of multiple effect evaporators in a two effect evaporator, the. This is to certify that the project entitled design and simulation of a multiple effect evaporator using vapor bleeding is an original work done by monalishanayak, roll no. National institute of technology, rourkela department of chemical engineering, national institute of technology, rourkela. An experiment with a singleeffect submerged vertical tube evaporator in multi effect desalination article in desalination 1561. Understanding such concerns and value of our customers efforts, we have been taking complete turnkey projects also, so that our customers have a total solution for their multiple effect evaporator projects and they enjoy a single and reliable source of supply. Evaporation normally produces a single vapor fraction, distillation several. The vapours from the preceding effect are used as the heat source in the next effect.
It is an efficient hydrating agent and it also provides skin with many nutrients and vitamins. Water required in a jet condenser for an evaporator 8. An iterative procedure previously presented in the literature lambert et al. The use of multiple effects enables a large number of possible arrays depending on the vapor and liquid flows. This system is used in a single effect evaporator or in the first stage of a multiple effect evaporator. Analysis of singleeffect evaporator desalination systems. These factors make effective evaporator control crucial to overall factory efficiency. Our modern production facilities, engineering excellence and highly experienced and dedicated team of engineers and technicians have made us capable of supplying wide range of multiple.
As a part of turnkey projects, we have been designing and developing axial flow pumps in various mocs which are regularly tested on our test benches and then dispatched to our customers. By increasing the number of effects we can increase the economy of an evaporator system. Hence, the supplied steam is condensed to give heat of condensation. Calculations on evaporators can be carried out combining mass and energy balances with the principles of heat transfer. Analysis of singleeffect evaporator desalination systems combined. A single effect evaporator desalination unit must have sufficient. Mee efficiency of mee types of mee advantages of mee cost reduction in mee. It was easy to control and had a compact arrangement. Multiple effect evaporator control is a problem that has been widely reported in the pulp and sugar industries. What is advantages of multiple effect evaperators over. Multiple effect evaporators advantages understanding the needs and concerns of our customers we have been taking complete turnkey projects. The proper design of the liquid distribution system is critical to achieve full and even product wetting of the tubes.
In a multipleeffect evaporator, water is boiled in a sequence of vessels, each held at a lower pressure than the last. What is advantages of multiple effect evaperators over than single effect evaporators. Verticaltube evaporators plate evaporators longtube evaporators forcedcirculation evaporators evaporation for heatsensitive liquids summary problems examples in this chapter. In a multiple effect evaporator, water is boiled in a sequence of vessels, each held at a lower pressure than the last. The configuration of a multiple effect system, as well as the setup of contracting methods, can optimize evaporator performance when dealing with high viscosity fluids. At first sight, it may seem that the multiple effect evaporator has all the advantages, the heat. Multi effect evaporator in a single effect evaporator steam is. Each effect, in itself, act as a single effect evaporator, and each has a temperature drop across its heating surface corresponding to the pressure drop in that effect. Advantages of multiple effect evaporator over single effect. Our organization is one of the most prominent and leading supplier and manufacturer of multiple effect evaporators. This concentrated liquids in a gentle and efficient manner in a way unparalleled in its time. Effects are thus numbered beginning with the one heated by steam. The characteristic is to heat the next effect evaporator by used steam produced from the front effect, so as to reduce energy consumption. The advantages of multiple effect systems relative to singleeffect, consist in.
Pdf desain multi effect evaporator dengan menggunakan excel. Evaporators are integral part of a number of process industries namely pulp and paper, chloralkali, sugar, pharmaceuticals, desalination, dairy and food processing, etc. An experiment with a singleeffect submerged vertical tube. Comparison between single and multieffect evaporators for.
During last seven decades, a number of models of multiple effect evaporator mee systems for its analysis have been reported. Plate heat exchanger, how it works working principle hvac industrial engineering phx heat transfer duration. Evaporated solute absorbed large amount of enthalpy, by condensing it in the lateral stage of evaporator would. What is advantages of multiple effect evaperators over than. Depending on lower in vapour pressure, boiling point of liquid also lowered as liquid move. Evaporators using steam to drive the evaporation process require less heat transfer area than hot oilheated evaporators. Sep 18, 2012 describes the operation of a single effect evaporator that is used to concentrate a solution. Jan 11, 2014 efficiency of multiple effect evaporator. In order that the steam provided by the evaporation in the first effect will boil.
What are the advantages of multi effect evaporator over single effect evaporator. Industrial evaporators falling film evaporator manufacturer. Psychrometrics psychrometric chart example1 psychrometric chart given dbt, wbt example2 psychrometric chart given dbt, rh. A multiple effect evaporator is an apparatus for efficiently using the heat from steam to evaporate water.
If the water vapor from the first effect of a multiple effect evaporator can be. As a part of forced circulation evaporator, we have been manufacturing and. Made by faculty at the university of colorado boulder department of chemical and biological. All heating of cool feed is done on the first effect, so that. In some cases, the first effect may be at a pressure above atmospheric. Multiple effect evaporators advantages shailvac surat. This problem is addressed to a large extent by the design and development of single effect evaporator desalination processes. Thermal vapor recompression tvr evaporator swenson thermal vapor recompression tvr evaporators use a thermocompressor to reduce the steam required per pound of evaporation. At first sight, it may seem that the multiple effect evaporator has all the advantages, the. Such systems are planned with a strong emphasis on their production capacity and cost. Single and multiple effective evaporator mee slideshare. A multiple effect evaporator is an equipment system for efficiently using the heat from steam to evaporate water. Evaporators are the largest heat users and major contributors to losses in sugar cane factories. Thermal vapor recompression tvr evaporator swenson technology.
Single effect evaporator steam usage and heattransfer surface 8. Evaporators singleeffect evaporator multi effect evaporator pan evaporator naturalcirculation evaporator rising film evaporator falling film evaporator risingfalling evporator forced circulation evaporator. The first effect of a multiple effect evaporator is the effect to which the raw steam is fed. Multiple effect evaporator free download as powerpoint presentation. Evaporation technology gea engineering for a better world. The stripper is part of the multiple effect evaporator system. Each effect would consist a heat transfer surface, a vapour separator, as well as a vacuum source and a condenser.
Cocoa butter has advantages of double effect on the skin. The principal advantage of horizontal tube evaporators lies in. The falling film evaporators can be single effect or multiple effects depending on the capacity. The latent heat in water vapor can also be reused by thermally or mechanically compressing the vapor to a higher pressure and temperature. Two or more evaporator units can be run in sequence to produce a multiple effect evaporator shown on the right. The process inside and andritz evaporator relies on a free flow falling film of liquor over the surface of the lamella. Mathematical model for a multiple effect evaporator system. Vapors obtained from first effect act as a heating medium for another effect.