Installation and method for purifying fluids by distillation

Abstract

The invention relates to a method and installation for purifying fluids by distillation, comprising: a reservoir (1) containing a fluid with diluted solids and comprising at its outlet an impurity filter (2); a pump (3) connected to the outlet of the reservoir (1) and designed to raise the pressure and temperature of the solids-containing fluid; and a region (4) for heating the solids-containing fluid which comprises a plurality of pipes in contact with a heat-carrying fluid; and which further comprises a converging - diverging nozzle (5) connected to the outlet of the heating region (4) and designed to increase the velocity of the two-phase vapour - liquid fluid such that the solids diluted in the already heated fluid are precipitated in a solids reservoir (6) whilst the fluid passes to a condenser (7) and from there to a reservoir (8) for the purified fluid which is already in the liquid state.

Description

[0001] PLANT AND METHOD FOR PURIFYING FLUIDS BY DISTILLATION

[0002] Object of the invention The object of the present invention is a fluid purification system by distillation that separates solids dissolved in the fluid by accelerating the fluid.

[0003] State of the art To date, the most common methods of water purification are by mechanical means and filters, as described for example in P201 130239. In this document, by way of example, it is indicated that a water purification device and procedure allows the filtration, potabilization and distillation of water by means of a single device, using only solar energy (UV radiation and IR radiation), also standing out for its portable and ergonomic nature, which gives it the ability to be used in any place and / or situation.This device is notable primarily for comprising a microporous bag containing a filtering material, such as activated carbon, ultrafine resin or similar, for filtering dirty water, removing any microorganisms, odor and color from said dirty water to obtain filtered water, as well as a container that has on its surface an area provided with thermochromic paint adapted to indicate to the user the moment when the contained water is already purified, by a change of color of said thermochromic paint after the water reaches a certain temperature during its exposure to sunlight.On the other hand, methods involving the use of membranes and vapor condensation are also used, as in document ES 2 388 882, which describes a method for purifying a liquid by membrane distillation, comprising passing a heated vaporizing liquid retained fraction stream through a retained fraction channel along a hydrophobic porous membrane, whereby the liquid vapor flows through the pores of the membrane to the other side of said membrane, and condensing said vapor on the other side of said membrane to produce a distillate stream in a distillate channel, the distillate being created by passing the heat of condensation.

[0004] (latent heat) towards a condenser surface, said condenser surface forming a non-porous separation between a feed stream of the liquid to be purified and said distillate stream, said feed stream being passed through a countercurrent feed channel with the retained fraction stream and whose feed channel is hydraulically connected downstream to the retained fraction stream, in which feed channel a spacer material is disposed, by means of which at least a portion of the latent heat is transferred through the condenser surface to the feed stream, and by means of which a positive liquid pressure difference is applied between the retained fraction stream and the feed stream at corresponding points of the retained fraction channel and the feed channel, at least on a portion of each of the retained fraction channel and the feed channel.

[0005] Description of the invention

[0006] As indicated, the object of the present invention is a method and a plant for purifying fluids by distillation that takes advantage of the fact that a fluid with dissolved solid components at high temperature and high pressure is passed through a nozzle until it reaches a speed close to the speed of sound.

[0007] As the fluid passes through the nozzle, its pressure drops, reaching a low pressure that causes it to reach its vapor pressure at that temperature. It is at this moment that the solid components separate from the gaseous fluid. Thus, the solid components are separated from the clean vapor, which continues its path to the condensation stage, where it is liquefied after purification.

[0008] Therefore, the present invention uses a distillation system to separate dissolved solids by accelerating the fluid to near-sonic speeds. This means that the liquid fluid, for example, seawater, is purified entirely physically, without any chemical treatments and without significant energy consumption, which can be obtained from clean energy sources. Throughout the description and claims, the word "comprises" and its variants are not intended to exclude other technical features, additives, components, or steps. For those skilled in the art, other objects, advantages, and features of the invention will become apparent partly from the description and partly from the practice of the invention. The following examples and drawings are provided for illustrative purposes and are not intended to restrict the present invention. Furthermore, the present invention covers all possible Combinations of particular and preferred realizations indicated here. Brief description of the figures

[0009] The following section briefly describes a series of drawings that help to better understand the invention and that are expressly related to an embodiment of said invention which is presented as a non-limiting example thereof.

[0010] FIG.1 shows a block diagram of a purification plant according to a practical embodiment of the invention.

[0011] Exposition of a detailed method of carrying out the invention

[0012] In a preferred embodiment of the invention, the production of potable water from water unsuitable for human consumption is proposed. Therefore, a cleaning cycle is proposed based on the separation of dissolved solids through the kinetics of a two-phase liquid-vapor mixture. For this purpose, it will be taken into account that: i. The temperature of the liquid must be raised to its boiling point under extreme pressure and temperature conditions.

[0013] a. Obtaining the necessary energy from any ecological system present in the surrounding nature of the place where the purification plant is located, i.e., wind energy, solar energy or any other renewable and / or low-cost associated energy; and

[0014] b. Performing the heat exchange with a primary heat transfer fluid configured as a heat transfer fluid to the system cycle.

[0015] i. Increasing the speed of the two-phase vapor-liquid mixture to speeds on the order of 450 m / s (Mach 0.85) which produce temperature variations of up to 60 e C for a few milliseconds, instantly breaking down the pure water from the salts present.

[0016] The result of the development leads to a process that obtains two products at the output: a) High purity clean water.

[0017] b) Waste in solid form (for example, in the case of seawater, common salt). Figure 1 shows an embodiment of the purification plant of the present invention. Thus, from a reservoir of water unsuitable for human consumption (1), the fluid passes through a first filter (2) to remove impurities, and by means of a pump (3), the pressure and temperature of the fluid are raised to a temperature not exceeding 253 eC. The fluid then passes to a heating zone (4) where the fluid is heated by a heat transfer fluid, which is at a temperature not exceeding 275 e C.

[0018] The heated fluid then passes to a convergent-divergent nozzle (5) that accelerates the fluid to speeds close to the fluid velocity (preferably on the order of 450 m / s), carrying out an adiabatic compression-expansion of the two-phase liquid-vapor system.

[0019] Finally, in each of the solids tanks (6), the solids precipitate at the bottom, while the purified water condenses in a condenser (7) to be stored in a purified fluid tank (8).

[0020] In the practical embodiment shown in Figure 1, several separation stages (5,6,7) are arranged which are fed back with different thermal gradients (difference between the inlet and outlet temperature of the fluid).

[0021] Numerically, in the plant shown in Figure 1 for a mass flow rate of 30 l / min and a thermal gradient between the inlet and outlet of 32.3 e C with a fluid density of 0.78 kg / dm 3 With a specific heat of 2510 J / Kg, 3 l / min of purified water and 105 gr of salt / min are obtained in the case of seawater, with a thermal balance of 13.35 KW / liter of water obtained.

Claims

1. - Fluid purification method by distillation comprising the following steps:i)              Providing a fluid with diluted solids from a reservoir wherein the fluid is sea water;ii)             Filtering the provided fluid from the reservoir (1) through an impurities filter (2); and comprising the following steps in order:iii)            To increase the filtered fluid pressure and temperature to its boiling point by:a.     a pump (3); andb.     a heating area (4) with heat exchange by means of a heat-transfering fluid;iv)            To pass the above fluid through a convergent-divergent nozzle (5) accelerating the fluid up to speeds approaching the speed of sound, whereby it produces an adiabatic compression-expansion of the biphasic liquid-vapor system, wherein the solids in suspension settle at the bottom of a solids reservoir (6); andv)             To condense the gas state fluid in a condenser (7). vi)            To pass the fluid to a purified fluid reservoir back in a liquid statewherein:the temperature is increased by a heat transfer fluid which is at a temperature not higher than 275° C.the pressure and the temperature are increased by a pump up to a temperature not higher than 253° C.the speed close to the speed of sound is of around 450 m / s. 

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