EA006523B1 - Stage of flash evaporator - Google Patents

Abstract

The invention relates to heating engineering for preparation of makeup water for use in heating systems, boiling rooms, hot water supply systems and can be used in petrochemical, pharmaceutical, electronic and in some branches of the food industry. The flash evaporator stage comprises a housing 1, a partition wall 2, which separates the evaporator stage into a condensing chamber 3 with heat-exchanging pipes and an expansion chamber 5, a vertical louver separator 6 with a separated water discharge pipe 7 fixed in the partition wall 2, branch pipes 14 and 16 for supply/discharge water correspondingly, a branch pipe for distillate discharge, a vertical partition 8, in the upper part of which an aperture A is provided for vapor flow and positioned along the partition wall 2 and forming two cavities 9 and 10 communicating therebetween by vapor in upper and lower parts of the expansion chamber 5, the cavity 10 in its upper part is provided with, at least, one channel 11 and water-distributing extension 12 for supply of superheated water from the water-distributing chamber, the height of the A aperture of the vertical partition 8 does not exceed the length of the water-distributing extension 12 and is 0.05-0.5 of the cavity 9 width, wherein a deflector 13 is made on the vertical partition 8 facing the water-distributing extension 12.

Description

The invention relates to the field of heat engineering, intended for the preparation of makeup water heating systems, boilers, hot water systems and can be used in the petrochemical, pharmaceutical, electronic and some sectors of the food industry.

Thermal desalination of water is one of the alternative ways of obtaining high quality water without chemical reagents, which are very expensive today.

Receiving a distillate by evaporation is economically efficient and is accompanied by a minimally harmful environmental impact compared to the most modern technologies of chemical desalting or reverse osmosis.

Steps of instantaneous boil-off evaporators are known, in which steam separation is carried out on louvered separators or net drip pans (see EI Taubman et al. Thermal neutralization of mineralized industrial wastewater. - L .: Chemistry, 1975, p. 47-60 ).

However, the operating experience of such evaporators confirms the impossibility of obtaining high quality distillate due to the fact that the steam entering the louver separator or the net drip catcher contains a large number of water droplets, that is, it has high humidity and, therefore, a large amount of impurities, and the drain is separated water is insufficient.

Also known is the evaporator stage of instantaneous boiling up, comprising a housing, a dividing partition, hermetically fixed in the housing with the formation of an evaporation and condensation chambers, a separator installed in the partition that passes steam and separates moisture, while the housing is equipped with nozzles for supplying and discharging evaporated water and a condensate drain (see ed. St. USSR No. 1733032, IPC On 01Ό 3/06, priority from 12/25/1989, published on 05/15/1992, bulletin No. 18, 1992, “Evaporator stage of instant boiling up”).

A disadvantage of the known device is that the sprayed water droplets freely fall on the separator, reducing its efficiency and the quality of the distillate.

The closest in technical essence to the claimed device is the evaporator stage of instantaneous boiling up, comprising a housing, a separating wall, separating an evaporator stage into condensation and expansion chambers, a vertical louvered separator fixed in the separating wall, branch pipes for supplying and discharging evaporated water, branch pipe for distillate discharge a vertical partition located along the dividing wall forming two cavities interconnected by a pair in the lower part of the chamber, the floor An awn, formed by a vertical partition and a stair case, in the upper part is provided with channels for supplying superheated water (see certificate for utility model of the Russian Federation No. 31337, IPC В 01 приоритет 3/06, priority from 31.03.2003, published on 10.08.2003, " Step of the evaporator of instant boiling up ").

In a known instantaneous boil-up evaporator stage, a vertical partition dividing the chamber into two cavities protects the separator from water ingress when splashing, water flows down the vertical partition to the bottom of the expansion chamber, and steam rushes to the separator, bending around the vertical partition at the bottom of the chamber.

However, at high steam velocities that occur when steam passes between the vertical partition and the dividing wall, water is captured by steam and carried into the separator, which complicates its operation and reduces its performance and distillate quality.

In addition, the supply of steam to the separator exclusively through the bottom of the chamber creates an uneven loading of the separator in height, which also reduces its performance.

The technical result of the claimed invention is to improve the quality of the distillate by reducing the moisture content of steam and improving the performance of the separator.

The technical result is achieved by the fact that in the inventive evaporator stage of instantaneous boiling up, comprising a housing, a dividing wall separating the evaporator stage into condensation and expansion chambers, a vertical louvered separator fixed in the dividing wall, branch pipes for supplying and discharging evaporated water, branch pipes for distilling distillate, a vertical partition located along the dividing wall and forming two cavities which are interconnected by a pair in the lower part of the expansion chamber, the cavity being about developed by a vertical partition and a step casing; in the upper part it is equipped with at least one channel for supplying superheated water; according to the invention, the channel for supplying superheated water is provided with a water distribution nozzle, and in the vertical partition in its upper part there is an opening for the passage of steam whose height does not exceed the length of the distribution nozzle and is 0.05-0.5 of the width of the cavity formed by the vertical partition and the dividing wall, while on the vertical partition is made ozyrek facing towards the water distribution nozzle.

Making a hole in the upper part of the vertical partition allows steam to be supplied to the separator both through the upper part and through the lower part of the chamber, that is, a double-sided supply of steam to the separator is achieved, which makes it possible to reduce the steam flow rate and thereby eliminate water trapping and its throwing into the separator , which helps to reduce the moisture content of steam and, consequently, improve the quality of the distillate.

In addition, double-sided steam supply reduces the aerodynamic unevenness of the steam flow in the separator, namely, to level the distribution of flow rates along the height of the separator, and

- 1 006523 also reduce the hydraulic resistance in the separator, which improves the performance of the separator and ultimately the entire evaporator stage.

The height of the hole in the upper part of the vertical partition, not exceeding the length of the water distribution nozzle, eliminates the possibility of overheated water entering the separator, including in cases of large temperature differences per evaporator stage, i.e. with a large overheating of water or a failure mode of operation, when water evaporates in the expansion chamber.

The ratio of the height of the hole in the upper part of the vertical partition to the width of the cavity formed by the vertical partition and the dividing wall in the range of 0.05-0.5 ensures uniform steam supply to the separator, which eliminates water trapping in the lower part of the chamber and contributes to improving the performance of the separator .

When the ratio is less than 0.05, the steam is not evenly supplied to the separator, and a slight change in the steam flow rate in the lower part of the chamber does not lead to the exclusion of water capture.

When the ratio is greater than 0.5, the steam flow in the upper part of the chamber becomes dominant, making it impossible to evenly supply steam to the separator and sharply increasing the humidity of the steam entering the separator.

The visor on the vertical partition, facing the water distribution nozzle, protects the separator from dropping water droplets through the hole in the upper part of the vertical partition.

The presence in the claimed technical solution of a set of distinctive features, not known from the prior art, allows to make a conclusion about its compliance with the condition of patentability "novelty".

The essential features of the claimed invention, predetermining the receipt of the specified technical result, do not explicitly follow from the prior art, which allows to make a conclusion about the compliance of the invention to the condition of patentability "inventive step".

The condition of patentability "industrial applicability" is confirmed by the example of a specific implementation.

The drawing shows the evaporator level instantaneous boiling in the cut.

The evaporator stage of instantaneous boiling up consists of a housing 1, a dividing wall 2, a condensation chamber 3 with heat exchange tubes 4, an expansion chamber 5, a vertical louver separator 6 fixed in the dividing wall 2, a drainage pipe 7 of separated water located along the dividing wall 2 of the vertical partition 8 with a hole And in its upper part for the passage of steam and forming two cavities 9 and 10, which are interconnected by a pair in the lower and upper parts of the expansion chamber 5.

The cavity 10 formed by a vertical partition 8 and the housing 1 stage, in the upper part is equipped with at least one channel 11 for supplying superheated water, and the channel 11 for supplying superheated water is provided with a water distribution nozzle 12.

The height of the hole And for the passage of steam in the vertical partition 8 in this embodiment is 0.24 of the width of the cavity 9 and does not exceed the length of the water distribution nozzle 12.

On the vertical partition 8, there is a visor 13 facing the water distribution nozzle 12. Evaporated water is supplied through the nozzle 14 and the water distribution chamber 15. The water from the expansion chamber 5 goes through the nozzle 16. The distillate discharges through the nozzle 17.

Stage evaporator instant boiling works as follows.

Overheated water through the nozzle 14, the water distribution chamber 15 and the channel 11 through the water distribution nozzle 12 enters the expansion chamber 5, where it is splashing and boiling, in which part of the water is converted into steam.

When spraying some of the water falls on the vertical partition 8 and the visor 13 and, draining from them, leaves through the nozzle 16.

The formed steam and water drops entrained by it through the upper opening A of the vertical partition 8 and the lower part of the expansion chamber 5 come to the separator 6, where a part of the drops precipitate and are discharged through the pipe 7 to the bottom of the expansion chamber 5 and further through the nozzle 16.

Cleaned in the separator 6 from water droplets, the steam enters the condensation chamber 3, where, passing through the annulus, it condenses on the heat exchange tubes 4 and flows to the bottom of the condensation chamber 3.

Pure distillate from the bottom of the condensation chamber 3 through the nozzle 17 is given to the consumer or goes to the next stage of the instant boil-off evaporator.

The use of the inventive evaporator stage of instantaneous boiling up in comparison with the known technical solutions makes it possible to exclude the capture of water and its injection into the separator due to bilateral steam supply to it, which helps to reduce the humidity of the steam supplied to the separator and create a uniform load on the separator, and also increases the performance of the evaporator stage instant boiling up and improves the quality of the distillate obtained.

- 2 006523

Claims (2)

1. The instant boiling-off evaporator stage, comprising a housing, a separating wall separating the evaporator stage into condensation and expansion chambers, a vertical louvre separator, nozzles for supplying and discharging evaporated water, nozzles for distillate removal, a vertical partition located along the separating wall and forming two cavities communicating with each other in a pair at the bottom of the chamber, and the cavity formed by the vertical partition and the casing of the stage in the upper part is equipped with at least one a channel for supplying superheated water, characterized in that the channel for supplying superheated water is equipped with a water distribution nozzle, and a hole is made in the vertical partition in its upper part, the height of which does not exceed the length of the water distribution nozzle and is 0.05-0.5 of the cavity width, formed by a vertical partition and a dividing wall. 2. The step according to claim 1, characterized in that a visor is made on the vertical partition facing the water distribution nozzle.