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Multiple-effect evaporator

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Multiple Effect Evaporators - Introduction

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ZERO DISCHARGE TECHNOLOGIES - Multiple Effect Evaporation

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Falling Film Evaporator

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Zero Discharge Technologies - Multiple Effect Evaporation System

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What is MULTIPLE-EFFECT EVAPORATOR? What does MULTIPLE-EFFECT EVAPORATOR mean?

A multiple-effect evaporator, as defined in chemical engineering, is an apparatus for efficiently using the heat from steam to evaporate water. In a multiple-effect evaporator, water is boiled in a sequence of vessels, each held at a lower pressure than the last. Because the boiling temperature of water decreases as pressure decreases, the vapor boiled off in one vessel can be used to heat the next, and only the first vessel requires an external source of heat. While in theory, evaporators may be built with an arbitrarily large number of stages, evaporators with more than four stages are rarely practical except in systems where the liquor is the desired product such as in chemical recovery systems where up to seven effects are used.