DE1812240A1 - Device and method for heat exchange in the vapor phase without the use of heat-exchanging surfaces - Google Patents

Description

PATENT LAWYERS DR-INa-H-NEOENDANK- difl-ino. H. HAUCK · difl-phys. W. SCHMITZ HAMBURG-MUNICH 1812240

ADDRESS FOR SERVICE: HAMBURG 36 · NEWS WALL 41

TBL. se 74> 8 AND »84110

TBLROR. NBGBDAFATBNT HAMBURG

MUNICH 13 MOZARTSTR. 23

TBL.088OS8 "

TBLBOR. NBGBDAFATBNT MUNICH

HAMBURG,

Nov 30, 1968

Montecatini Edison S.p.A. Milan (Italy)

Device and method for heat exchange in the vapor phase without the use of heat-exchanging surfaces *

The invention relates to a device and a method for heat exchange in countercurrent between two columns of liquid by means of successive evaporation and condensation from one to the other pillar.

- ♦

The advantage of such a device and method is that the heat exchange can be done with the use of little energy and without the use of heat-exchanging surfaces »

By suitably designing the device and by means of additional devices, the device of the invention can be used for many different practical purposes and, for example, can then

009808/0235. ₂ .

- »2 -

be used when a certain liquid or a certain fluid in the water should be subjected, "for example ma iie germicidal To take advantage of the effect of temperature and pollute To transfer water to drinking water.

The device of the invention can also be used very well for water de-alcalation terfaiirea. Salty or saline water can be subjected to heat pre-treatment by means of the device in order to taingenj the salts contained in the water for precipitation, which become insoluble under the influence of temperature are inevitable.

Insoluble salts can be in the form of a Slurry easily from the device according to the invention remove and the water purified in this way can for the purpose of further treatment of the desalination plant are fed.

The invention also relates to a method for heat exchange in countercurrent between two liquids Flows by means of the flow rate according to. Siiij. Direction, in which the heat exchange in the connection & n-successive yerdampfuagen in a liquid stream with

009Ö0a / 023S

automatic heat transfer takes place on the Pressure difference between the vapor obtained in each evaporation of the one liquid stream to the is to be returned to another, heated liquid flow, in which the vapor condenses on direct contact with the liquid stream.

It should, and therein lies the object of the invention, a simple and easy to use device sun heat exchange between two liquid streams without Use of heat-exchanging areas can be specified.

This device is intended for the purpose of exchanging heat between the liquid to be cooled, which is in the vapor phase, and the heated liquid only need a small amount of energy.

Furthermore, a heat exchanger should be specified which is not affected by the main parts of known designs and heat exchangers caused by deposits and the like, as can be observed, for example, in the known heat exchangers with combined tube bundles.

In addition, a method for heat exchange between liquids in the vapor phase by means of the Device according to the invention are specified.

The advantages created by the invention, 009808/0235 ~ ⁴ ~

. 4 - f8122 * 0

and Herlnale the invention are apparent from the following description "which © ine means for heat exchange between fluids in the vapor phase belnhaltet _f the u-erfinämngegemäß egenstrpm of two in-flowing liquid column !! ordered »whereby the liquid in one column, as a result of the decrease of the hydrostatic bridge at different geometrical heights, is subjected to successive evaporation, and with formation. vorgeeeliea eini "to guide the to NEN ii © _f the b © l each Terdampfung generated Baiipf s & the other column in which it is condensed

The invention is based ier! "! Assembled calculations explained _v the Zeidmuugen is only a Ausfuhrujogebeiapiel for Srfindung iseigexi · In the drawings s

Fig. 1 shows an implementation of the device of the invention in sciieaatiBcher Barstelluiig in the length section _f

fig. 2 a. Cross section - along the line 2-2

the fig »1,

fig. 3 eiae sur SrHämag ilenenfle Baretelluuig for the Aiisfiünuigsform after, the -Mg »1 _f

fig »4 eiae echenatic Sarstellusg bucket al) changed Fixation of four plates in the vapor column,

!1! ¹¹¹ Ji ¹ IlIiIi.; !! ;;;: ϋ.? ¹ 1 ;; »·.: - '. J:. ■■■■ ,. a., »ι vw> ,,« ίι ... .- ■■

■ ■ "/ ■■ ^: ■ ■■ '■■■ ■ ■ ■' ■■ ■

a schematic representation of a modified layout of the facility, in which the two columns are formed by two concentric tubes,

fig. 6 a thematic representation of a

Equilibrium evaporation system for Desalting of saline Vaeaer, the Device of the invention is used in this system, and

Fig. 7 is a schematic representation of a

Equilibrium evaporation system for Desalination of saline water, in which several devices according to the invention are used.

In the figures of the drawings, which have been described above, an embodiment is shown by which it is intended to subject a liquid to a heat treatment, the the same liquid is heated in one column and then passed into the other column in which it is cooled.

If only a pure heat exchange is intended, the arrangement has a separate outlet and inlet for low temperature and a separate outlet and inlet for high temperature.

009608/0235

Although the circulating in the counter-described examples in the two columns of liquid is AEIE same should be noted, the device of the invention dai after making appropriate iaderoageii, which are also used further to the Pachmanii entirely familiar sinc3 "oime taan _f in the Lay columns of liquids underneath the silicified taffeta so that they circulate "

As # 1 and 2 ^ consists of the]? Ig apparatus of the invention, aueh AEIE as "apparatus" may be referred to, from a tube 1, üae substantially vertically disposed and d, eating upper Eaien, 2 and 3 in opposite directions curvedE. The two bands merge into two sections 4 and 5, which are connected to the two vessels 6 and 7 by a hydraulic seal, but free surface surfaces have a ^{height difference denoted by 1} H '. Vessel 6 represents the inlet side of the * Device for the liquid to be treated, which represents the vessel 7 on the outlet side for the liquid. The free liquid surface of the clef is at a greater height in relation to the surface of the vessel 7 on the outlet side, so that the external flow of liquid maintained by the device in a natural way j so-feald the device is "ignited ⁰ , ie has been put into operation,

- 7 ÖÖ98Q8 / Ö235

The height difference Ή * of the two liquid ^{levels is different from I 1} SJLl cn case and depends in particular on the density of the liquid circulating in the device and on its flow rate.

In their «upper end is the pipe or the tube 1 connected to a suction device via the two upper ends 2 and 3, which not only "ignites" serves the device, but also improves the liquid circulation and allows the non-condensed or non-condensable substances, such as Suck out air. Meanwhile in the upper part of the upper ends 2 and 3 by means of the suction device 8 a suitable one Negative pressure is created, liquid can naturally circulate through the pipe 1.

The tube 1 is of circular cross-section and in its length by means of a wall 9 in two sections or columns 10 and 11, which form the two columns in which the successive evaporation and condensation occur at different heights, which cause the heat exchange. The two columns 11 and 11 are connected to one another via an opening 12. The opening 12 is located at the lower end of the Wall 9 and allows the liquid to pass from column 10 to column 11. Through further openings 13, which are arranged in the wall 9 at different heights

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ORIGINAL INSPECTED

- β -

are; may vapor generated in the column 11 to the column 10 arrive, in which it condenses.

In every section of the pipe 1 there is pressure, which in a first approximation depends on the height of the section in question. Therefore experiences circumferential through the pipe 1 Fluid pressure changes that occur between sswei predetermined values. In section 4 on the inlet side there is a lot of pressure erosion » whereby air is developed which goes to the upper zones of the tube end 2 and from these mediates the suction ™ device θ is removed.

At the lower end of the tube 1 there is a heat source 14 "which supplies sufficient heat" to heat the liquid in this zone to a temperature which, at the pressure prevailing at this point, is just below the boiling point. Therefore, when the liquid begins to rise in the column 11, it is evaporated due to the pressure drop.

That part of the Strifmiingekreislaufes, CDCR is enough in the column 10 .. by the end on the barometric pressure EinlaSabscimitt 4 to zn of tiefet © »Location 12 dee system capacitor is to be called the column.

That rope of the flow circuit "that calibrates

in column 11 τοη the deeper point 12 up to the »

00S808 / Ö23S

- 9 - ORIGINAL INSPECTED

[■ '.,: ■■■ ■■■■■■ ■■ ^- ■■. . '■ ■■■!. ·. . , ■ r. , (,, .. ..,. j,; _{n f fi i}

* ' '■ ".._ ■■■ ..» ■ ,,. ■ ", |". _I

The beginning of the outlet section 3, which is under a barometric bridge, is to be called the evaporator column will.

Within the condenser column 10 or the evaporator column 11 are baffles, of which an embodiment is shown schematically in FIG. 1 and denoted by the reference numerals 15 and 16. These baffles have, among other things. the task of interacting with plates 17, the main purpose of which is still further below Part of the description is explained in order to form the liquid path in the two columns 10 and 11 sinusoidally, as indicated in Fig. 1 by arrows.

As shown in FIG. 2, which shows a cross section along the line 2-2 of FIG. 1, the baffles 15 and 16, as well as the plates 17 _t, provided that the pipe 1 has a circular cross section, the shape of circular segments and are on any known tit within the Rohrβ 1 attached. The plates 17 and the baffles 15 and f6 are arranged inclined to the vertical within the columns, their angles of inclination to the vertical being Oi t ß and V. Contrary to the illustration in FIG. 1, these angles of inclination can also be different from one another.

In order for the plates and the deflection surfaces to be able to perform their intended task, the inclination

- 10 -009808/0235

angle οέ of the plates 1? wad less ale 90 °, the inclination angle β. and J ^ eollen also preferably be less than 90 °.

Fig. 1 also contains the following reference symbols: 18 denotes the tapping points Ib the baffles » 15 »äas reference numeral 19 denotes the Separation limit toh liquid and steam; iie dashed Arrows 20 show the steam is flowing away. * Walareai iie la excellent Arrows 21 shown in the lines denote the Elfissigkeitsweg indicate; 14 denotes oils heat source; 22nd 'indicates a device for the administration of insolubles Salts and oils precipitate on the boaen'des pipe 1.

It does not need to be particularly mentioned here that other arrangements can also be made within the framework set by the invention. Baffles and know find Yerwenäiing plates "Inebesoaclere Irönneii be generally formed lall üie AblenkblBche and the plates in the Eondensatorsäule different from the baffles and plates ready in 4-evaporator column .. As mentioned _$ steüen the beiflea Säulea but openings 13 with each other, the As is shown in the drawing, below the flat? are arranged and dieneiij the discharge of the steam tob. to enable the evaporator column in which it is generated, so that the 35arapf can gradually reach the condenser column in which it condenses. the

009808/0235 - - 11 -

Both of the aforementioned columns can be formed, for example, by the circular ring section between two mutually consistent tubes, as is generally the case and is shown schematically in FIG. In the in In this arrangement shown in the figure, the condenser column 10 is formed by the between the concentric tubes 28 and 29 lying annular space is formed, while the evaporator column 11 is formed by the tube 29. In this embodiment, the plates 17 have the evaporator column 11 an annular shape and the baffles 16 are circular. The view of the under a plate located openings 13 can be different and depends on the respective requirements.

Tube 1, which forms the two pillars 10 and 11, has a circular cross-section in the embodiment of FIG. However, other cross-sections can be used as required. In addition, the two of them can Columns consist of a single, U-shaped bent tube, the two arms of which correspond to the plates through Connection pipes are connected to each other.

The operation of the device according to the invention shown in Fig. 1 is as follows: The temperature of the liquid in the condenser column 10 is slightly below the at all points Boiling point, which is given by the pressure prevailing at this point, which in turn depends on the geometric

009ÖO8 / 0235 - 12 -

ORIGINAL INSPECTED

Irish height of the point or the point depends on which is given by the pressure prevailing at this point, which in turn depends on the geometric height of the point. The liquid flowing through this column is gradually cooled as a result of the successive evaporations. At a certain height of the Terdampfersäul® the temperature is slightly higher than the temperature at the same height in the condenser column. For this reason, the temperature of the liquid emerging from the system at the outlet at a vessel 7 is higher than the temperature of the liquid at the inlet vessel 6, the difference in the heat contents apparently being equal to the amount of heat _t which has been supplied to the system at point 12 is at which the liquid flows into the evaporator column 11 at the lowest point by means of the heat source 14.

At the inlet located at the lowest point, the liquid therefore enters the at a temperature Evaporator column 11, at which it is about to cook begins. As the liquid flows through this column, it gradually loses its pressure and evaporates fi with iii such a measure as is necessary to

009808/0235

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to cool down to a later lower temperature that corresponds to the prevailing pressure.

The steam developed in this way at different heights in the evaporator column 11 is retained by the plates 17 which are arranged in the column and forms steam pockets on these flats. Of the The pressure in such a vapor pocket corresponds to that prevailing at the level of the separation limit 19 of the liquid Pressure and is thus higher than the pressure in the condenser column 10 at the level of the flow opening 13, which is at a higher point than this separation limit 19 (Pig. 4).

In fig. 4t in which two successive plates of the device according to the invention are shown, / ± H represents the difference in height between the center line 25 of the opening 13 and the evaporation limit 19. This difference in height allows, as already mentioned, the outflow of the vapor in the zone 26 of the evaporator column to the condenser column 10 on the left. In addition, Pig. Figure 4 shows a somewhat different embodiment of the plates 17 which is also within the scope of the invention.

In the arrangement shown in Fig. 4, the plates

in the condenser column 17 '/ the same shape as that of the arrangement of FIG. 1 and have an angle of inclination Oo with respect to the vertical which is smaller than 90 °, whereas the

009808/0235 -U-

Plates 17 in the evaporator column 11 at an angle are arranged at 90 ° to the vertical and in this case, however, have an undercut hand 27, where the undercut relates to the direction of ascent refers to the liquid in the evaporator column and the * formation of a vapor pocket in the zone 26 under the Plate 17 permitted.

The plates 17 located in the evaporator column can with respect to the vertical even around one Be inclined at angles of more than 90 °, provided that they are provided with an undercut 27. For training of the steam pockets, it is necessary that the plates 17 with respect to the vertical one substantially Form concave space. In this way, the steam thus formed and accumulated in the pocket to the condenser column.

Me dimensions and the design of the plates of the evaporator column, as well as the flow openings must be chosen in such a way that it is ensured that the üresmmgs- or separation boundary between liquid and vapor cannot reach the lower edge 23 of the plate 17, since Waue otherwise reach a.uf this Mege steam in the next Stuf3, could reduce the efficiency of the system "the steam that has check, however, formed according to the liquid in the DarelifluSabselmitt" is subtracted in the next stage.

009Ö08 / 0235

The amounts of steam released in this way from the evaporator column to the condenser column meet in the counter-atmosphere on inter colder liquid and are therefore sooner or later condenses. The dimensions and design of the plates of the condenser column buses should be chosen so that it is ensured that these condensations take place before the steam reaches the upper edge 24 of the plate 17, otherwise the steam will pass into the next stage and the efficiency of the system would degrade. The baffles 15 and 16 have the task of extending the path of the liquid in the two columns and thus the evaporation and favor condensation and also act as deflecting devices which prevent the steam from flowing away Prevent su the subsequent stage, preferably by guiding it under the plates 17 (mediate the Deflectors 16), and possibly non-condensed steam and air, collect via the tapping points 18 of the to the next stage (by means of the baffles 15).

The theoretical considerations by means of which these phenomena can be quantified should be are not presented here in detail, but for a better understanding some conclusions should be given that result from these theoretical considerations: a) The specific heat demand required by the system

009808/0235

ORIGINAL INSPECTED

to give the liquid the desired heat treatment subject is given by the product of the flow (the flow rate) of the liquid flowing through the system with the specific heat of the liquid » multiplied by that existing between two successive plates 17 in the higher zone of the system itself Temperature difference (i.e. at a lower pressure). This temperature difference is dependent on the distance these panels. This amount can be reduced at will by reducing the distance between the different plates , whereby of course the technological conditions must be taken into account. In practice it must the heat demand given above must be multiplied by a number between 1 and 2, which in turn depends on the dimensions of the facility.

b) As soon as certain dimensions of the system and a certain distance between the plates in the south pressure zone have been specified, the specific heat requirement is also specified. In this case it will be the greatest Economy or savings in the number of plates used are achieved if the distance between the plates

ten is different and gradually increases towards the bottom of the column.

The least number of plates results when the plates are arranged in such a way that the temperature difference of the liquid between the temperature

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temperature at the level of one plate and the temperature at the level of the following plate is constant , even if the same amount of steam is processed in each stage between two successive plates.

c) The output of the system, viewed as the relationship between the heat consumed and the heat exchanged, is in general quite good and takes, if all other circumstances (including especially the one already mentioned above) Minimum distance between the plates) remain unchanged, to:

- with the increase in the difference between the extreme temperatures of the system, i.e. with the height of the columns;

- with the decrease in the given ratio between specific heat and for a given liquid Heat of vaporization;

- with increasing influence temperature;

- with decreasing volatility and decreasing density of the liquid.

d) In order to achieve a good yield, it is crucial that when designing the panels in the gravure zone special attention is paid, especially when the influence temperature is low.

e) The system itself develops a fluid propulsion force which result in a circulation of water in the system * calls.

f) The electric circuit, that is, the circuit is related to

009608/0235

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every disturbance self-stabilizing. This stability can be achieved by suitable throttle valves at the inlet of the condenser column or increased at the outlet of the evaporator column.

The tests carried out on a prototype of the device described above have confirmed the results of the theoretical considerations and provided valuable practical advice.

) It has indeed been shown that the plates

the condenser column work properly if they are designed according to the schematic representation of FIG even if the panels are only slightly inclined to the vertical. A certain advantage could be achieved by rounding off the outer bands 24 and 23 of the plates, when these are upwards or downwards. were rounded towards the bottom.

With regard to the plates of the Terdampfersäulen \ the embodiment shown in Fig. 4 has given good results. Apparently a ratio of 0.4 for the cross-section of the passage A of the liquid entering the evaporator column to the total cross-section B of the evaporator column is a suitable value »

It has also been shown that the system is best of such dimensions that give the guarantee that that the speed of water flow between

009808/0235 - 19 -

the narrower sections A of the vapor column _{does not exceed the value of O f} 25 m / sec. In the system in which the tests were carried out, the columns had a diameter of 270 mm and the maximum permissible flow rate should therefore not exceed the value τοη 20 m / h for the reasons given above.

Furthermore, it has been used to stabilize the system, especially during commissioning and during shutdown, proved necessary one Edge 27 of the in Fi $. 4 to be provided training shown. The formation of this edge enables the problem to be solved, namely the optimal solution for each individual

Pail to be determined constructively.

During the experiments, the observation was made that it is useful to have a certain turbulence in the condenser column, as a result of which a load loss (pressure v.) about 40 to 50 cm of water has to be accepted. the Turbulence is achieved by means of the baffles 15. In order to bring the various pressure drops to zero, it is convenient to at the base of the columns at the point which passes the water from the condenser column into the evaporator column, to use a pompe of low conveying pressure.

For a better understanding of the advantages obtained by the device according to the invention, the following described a numerical embodiment that

009808/0235

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ORIGINAL INSPECTED

serves only to explain the invention.

Example 1 s

For the execution of this application example, a system formed from a descending condenser column and an ascending evaporator column was used, in which the two columns (which for the sake of brevity are to be briefly referred to as "evaporator ¹ * and" condensate or ⁿ ) were connected in series . The circulating liquid is water. Both columns were made from carbon steel tube with an outside diameter of 273 mm. This tube is bent into a U-shape and the whole device measures about 25 m from its highest to its lowest point . The two columns are each provided with a series of plates which allow the vapor developed in the evaporator to accumulate and the local condensation of the vapor coming from the evaporator to collect in the condenser. In order for the vapor to pass from the evaporator to the condenser, the two columns are in communication with one another along their entire length via a series of passages, one passage being provided for each plate. The vapor transfer is guaranteed by the pressure difference of

0098 087 02 35

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about A H equals 25 ml of water column (Pig. 4) through the height difference in the evaporator between the evaporation surface of the liquid phase located under the collector plate and the axis of the corresponding one Connection pipe is given.

By this system the descending in the condenser water is kept substantially saturated and increase its own temperature of ⁰ C to 50.67 125.93 ⁰ O at the expense of the exhausted vapor from the evaporator, wherein the rising water has a temperature of 126 79 ⁰ C at the lower ^{end drops to 51 168 0} O at the upper end. IAQ a continuous circulation to ensure it is necessary the temperature of the flowing out of the condenser water (125.93 ⁰ C) to the temperature of flowing into the evaporator to increase water (126.79 ⁰ C). The amount of heat required for this is supplied at the lower end of the device by blowing in saturated steam below 3 ata.

The minimum amount of heat that must be supplied amounts to :

^ps «n ^{t ne ~ * ηο> · ^w0 * ^ei

Q _n s is the flow rate when flowing out of the condenser and when flowing into the evaporator, expressed in kg / h.,

* ne * ^the 3taBperatu? at the lower end of the evaporator in ⁰ C,

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009808/0235

t = the temperature at the lower end of the condenser,

. O"
measured in C.

It follows (if the data in the table below are taken into account) that:

P = 46880 (126.79 to 125.93 C ⁰⁾ = 40371 kcal / h.

The saturated vapor below 3 atg brings the liquid from 125.93 ⁰ O to 126.79 ⁰ C and delivers:

650.3-127.2 = 523.1 kcal / kg.

The minimum amount of steam that is at the bottom, i.e. at the bottom must be blown into the facility is therefore:

= 77.07 kg / h. .

The columns of this embodiment are shown schematically in Fig. 3 of the drawings.

The following table gives the corresponding numerical data (which have been approximately confirmed by the tests carried out and, in contrast, can be derived theoretically in the absence of pressure losses), the flow velocity of the liquid being ν = 0.25 m / sec and ρ = the pressure, if the pressure losses occurring as a result of the water circulation are neglected, tj ss the temperature, measured at the evaporation surface of the water (separation limit 19), t ₂ = the temperature, measured in the liquid immediately below the evaporation surface, h = the assumed distance between the plates, which is used in the construction in the different zones of the columns, and Q = flow rate.

00980Ö / 023S _ ₂₃

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TABEL

Condenser column Evaporator column

P ₀ ata

kg / h

"ο cm »Ι ata 1 °° «Ϊ ' kg / h ^η 1 cm ata kg / h om ata 3:00 ι * · kg / h cm

ata

Qk kg / h ^h k cm Pn ata *1 ^t 2 Qn kg / h

0.13
50.67
40,000
5

0.137 51.45 51.43 40,054

5.2.

0.735 90.6 90.6 43,000
21.6

1.33 107.1 107.1 45,160
36.5

1.92 118.3 118.3 46,120
49.8

2.50 125.93 125.93 46,880
60.8 0.137 51.68

52.14 40,054 5.2 0.735 90.7 91.53 43,000 21.6

1.33 107.1 107.99 45,160

36.5

1.92 118.35 119.17 46,120
49.8

2.50 125.93 126.79 46,880
60.8

The indexes of the symbols refer to the general altitudes of zones 0, 1, i, j, k and n, the are given in the schematic representation of FIG.

00980870235 - 24 -

As already stated, the device of the invention can be advantageous in desalination processes for saline or salty water are used to expose this water to a warming which the Precipitation of these salts, including calcium sulphate, for example, causes their water solubility decreases with increasing temperature, which prevents these salts from being deposited in the desalination plant otherwise in the form of harmful deposits or crusts on the heat exchange Serving surfaces were settled, which in turn results in the disadvantages well known to the person skilled in the art.

In this context it should be pointed out that, for example, in desalination plants with Equilibrium evaporation, i.e. the facilities of the so-called "Flash type" the deposits on the heat exchange tubes pose a problem that significantly affects the effectiveness. As a consequence, the service life the system is significantly shortened and there is always an upper limit value for the operating temperature that can be achieved. Conversely, if higher operating temperatures could be achieved, operating costs could be increased of the system can be consistently lowered.

These deposits are due to the salts, which have a lower solubility at higher temperatures have, including in particular calcium sulfate

00980Ö / 023S " ²⁵ "

falls. For this reason, solutions that are undersaturated at a low temperature become undersaturated at a higher temperature Temperature oversaturated, so that as a result these salts precipitate and deposits on the heat exchange Serving surfaces of the plant are formed.

Venn the water to be treated, i.e. the saline water, before being fed to a normal flash system is pretreated in order to free it from the abovementioned salts, the disadvantages mentioned would not occur and it would be possible to reach higher temperatures in the flash system itself. Such a pre-treatment can result in a heating of the water (of course without the use of metallic heat exchange surfaces, since deposits would otherwise form on these) in a simple and inexpensive manner by means of the invention Facility that does not require exchange surfaces due to its training. In this case it is sufficient to preheat the saline water to a temperature that is higher or at least equal to the temperature, which is achieved in the flash system. In any case, the saline water must be at a certain temperature which corresponds to the temperature of the lowest solubility of these salts.

In this way, the saline water is brought to a temperature at which the precipitation of the sedimentation salts occurs in such a zone of the plant (both

- 26 -

0091808/0235 originally inspected

for example in the establishment of the 3? ig. 5), in which can form salts no- deposits and instead in a slurry accumulate, which can be removed in various ways for their part, for example by means of a lower outlet or by filtration of a suitable recycle stream · In the inventive device, it did possible to arrange a vessel at its lower end into which the water from the condenser column is introduced and from which the water that enters the Terdaapfer is drawn off, the precipitation and removal of the slurry taking place within this vessel.

Experiment with seawater, especially seawater, and with other water that has been purposely substituted with additives and containing calcium sulfate have confirmed that the injection of steam into the bulk liquid the predicted effect and the concentration of the deposit-causing salts as a result the precipitation of their supersaturation content is significantly reduced.

It has been shown that the effectiveness of the cleaning described in the doorstep is under the condition it is given that the water to be treated is at rest for a certain period of time at the treatment temperature can linger.

- 27 009808/0235

ORIGINAL INSPECTED

Since the deposits in a flash-type plant occur at certain temperatures and these are generally designated by T ^, the device used for pretreating the water according to the invention can, for example, according to the scheme of Flg. 6 can be used. In this schematic diagram, the Flash type facility is in two sections divided, of which one section is at a temperature below T ^, where no cleaning action is required and the other is at a higher temperature at which Water that has already been pretreated is used. The filling with brine or salt water, the removal of the Brine and the renewal of the same in this section of the system is carried out by means of another flash line, for this purpose a device or apparatus 30 according to the invention between the low temperature line section and the assumed high temperature section is interposed.

In the schematic representation of FIG. 6 (like < also in Fig. 7) there are two flash sections at a low temperature and one flash section at a high temperature.

The feed and top-up speed for the high temperature section is the same

- 28 -009808/0235

just the flow rate through the device 30. Um To follow the pressure behavior in the various points of the circuits, the height alignment of the Plant must be taken into account, with the lower ends of the pillars in the device on the same (or a slightly larger) height than the flash sections are supposed to be and therefore their heat at a height accordingly is higher.

It should be noted that with such an arrangement, the calories supplied to the device in the water reproduced by the device can be found again and therefore these calories actually are lost for the high temperature section of the plant (the other without the presence the facility could not be present by definition), but for those under low temperature standing flash section can be fully recovered, the latter section of the plant represents the only part of the same, which is also provided without the presence of the device can be.

Consequently, the installation of the invention disturbs or burdens Establish the economics of a hypothetical flash facility with its own limitations the temperature, but allows the production of fresh water with the same heat consumption

009808/0235 ~ ²⁹ ~

'"'"'"■'"'*'"""'"' ^: · ■■■■ '■ ■ ■ ■ ·' ■ ■. ■ <■ ■! ■. ■ ·. ■ -r: ir: · IiJISSiIiIi PhI [SIi: ¹ -. -

in the section of the plant at higher temperatures, with the facility itself having higher temperatures ! Temperature enables.

It should be noted that in order to achieve the high temperatures in the flash system, similar temperatures must be achieved at the bases of the columns located in the device. Since these temperatures correspond to higher pressures and therefore also to higher heights of the columns themselves, certain technological difficulties may arise under certain circumstances. For example, if the temperature T ^ at 100 ° C and diesel highest operating temperature should be at 180 ⁰ C corresponding to a bridge of 10.2 ata, the corresponding height of the column would be approximately 90 m.

The problem arising as a result of this excessive height can be mediated by the in Pig. 7 can be achieved by dividing the height, for example, between the two units 30- and 30 ". Nothing stands in the way of extrapolating the idea implemented in this scheme in the direction of a larger number of such pillars. In the proposed case it is possible, for example, to subdivide the required total height of 90 m into four facilities, each with a height of 22.5 m, whereby the high ridge can only be reached in the last columns. In this way, the columns can be much easier and

- 30 009808/0235

and manufacture and build cheaper.

The following is a more detailed description of the schematically illustrated in FIGS. 6 and 7 Embodiments are given to the application the Einrichfcung according to the invention on a system of the Flash type for the desalination of sea water closer to explain.

In Fig. 6, 'a' represents the inlet system through which the seawater to be treated is supplied, 'b' shows the delivery of the brine (water with a high salt concentration), ¹ C ¹ 'is the delivery of the desalinated water, 'd ¹ the release of the salts made insoluble by the effects of the device 30 of the invention (such as GaSO,),' 31 'is a conventional heat exchanger which supplies the heat required by the system by means of steam in the spirals 32,

The system consists of a flash line at a low temperature between Tq and T ^, which ^{is to be denoted by 1} A ¹ and is formed by a spiral system 32, da3 through the steam of the flash system or through the corresponding pressure extraction lines of the sols 33 and the condensate 34 is heated. The brine is partially circulated by means of a pump 35, with part of the brine, which ^{is denoted by 'b 1} , being returned directly to the sea and the condensate' c ^{1 being}

009808/0235

is won. The line ¹ A * is filled in that sea water is sucked in and conveyed into the spirals 32 of the flash line ¹ A ¹ by means of a pump. At its head end, the line ¹ A * receives heat from the last stage of the flash line denoted ^{by 1} B ¹ , which operates at a temperature between T * and T _f and to which heat is supplied from an external heat source.

The liquid flow x-k + i, which is ^{circulated in the coils 32 of the flash line 1} A ¹ (where "i" is the current condensing in the line 41 of the flash line B), is pumped further, separately, by pumping the portion ¹ I ¹ into the spirals 36 of the line B and the portion zk into the brine line of the line ¹ A ¹ . The liquid flow circulated in the spirals 36 of the line ¹ B * is then x + i.

Furthermore, a third flash line is provided, which ^{is to be denoted by the reference symbol 1} C and is constructed similarly to the two flash lines mentioned (its task being to fill up the ^{line 1 B * in front of it).} In this third flash line ¹ C * a Neerwater stream 'k' is introduced into the spiral system 37 at such a pressure that the liquid pressure prevailing at the outlet of the system is sufficient to bring the liquid to the level of the head of the device 30 and this in the

009808/02 3 5, ... - 32 -

introduce appropriate condenser column. This stream of liquid heats up on its passage down the column in the manner already described until it has reached a temperature sufficient to produce the necessary cleaning action, which is the gate exposure for the liquid to be in a suitable form, when it is then introduced into the flash line ¹ B 'which is under high temperature. In practice the liquid flow at the base of the device 30 is at a temperature which is slightly higher than T _f . After the water in the condenser column has been subjected to the purification already described above, and after it has been warmed up from the outside by the steam in the coils 32, it flows into the evaporator column and, when leaving the same, is in the coils 36 of Flash line ¹ B * initiated.

This liquid flow k becomes the flow z-k + i coming from the brine line 39 from the flash line B is added and is converted into "the corresponding spirals are initiated, the liquid flow then being a total of x + i.

The liquid flow x + i is heated to the temperature T _£ and then introduced into the corresponding brine line. From this brine line at one point

009808/0235 - 33 -

at which a suitable temperature prevails, a liquid stream k is drawn off and into the brine line the flash line 'C initiated. The water given off by the latter is immediately and without renewed Upheaval returned to the sea.

The system shown in FIG. 7 consists of four flash lines A, B, B ¹ and C, which correspond to those of FIG. The same reference numerals as in Fig. Designate corresponding parts, streams, etc. In the arrangement of Fig. 7, however, the height of the apparatus or device 30 shown in Fig. 6 has been divided into two units, denoted by 30 * and 30 " In the line ¹ A * flows, in the same way as in the arrangement of FIG. 6, a liquid stream x-k + i (where i is the flow through the condensation line 41 of the flash line ¹ B *) through the spirals 32 ) and the same circulation, introduction and supply of heat from the line ¹ B ¹ occurs, as has already been set out in connection with the arrangement of FIG.

A liquid flow x + i is circulated in the spirals 36-of the line ¹ B ¹ , the portion of which ik-ofk + i by means of the pump 33 into the spirals 36 of the line B (where oi. K is the portion of the water by which the Liquid flow k has been enriched in device 30 ', as will be explained below), and its proportion k * oC k in the evaporator column of the one

OO & 8O0 / O2 3S _

direction 30 · is initiated. After the latter liquid flow has passed through this column and has in the meantime become k, it is by means of the pump 38 together with the flow x-k + i, which comes from the brine line 39 of the flash line B * and for the portion i comes from the spirals 32 of the line ¹ A *, is pumped into the spirals 36 of the line B. The brine line 39 of the line ¹ B ¹ (which forms an extension of the brine line 39 * of the flash line ¹ B *) is fed by a current x + i which ^{comes from the coils 36 * of the flash line 1} B ¹ and through the heat exchanger 31 has been warmed up from the outside. From the brine line 39 of B, a current k is drawn off at a suitable point, which is used to feed the brine line 40 in the flash line ^t G ¹ .

The sea water for the liquid flow k is pumped into the spirals 37 of the line ¹ O ¹ and is the same of the device 30 * is introduced into the top of the condenser column at the exit. When this current comes out again at the base of the condenser, it has become 1 £ + O6 k as a result of the steam supplied and is pumped by means of the pump 42 to the top of the condenser 30 * ', passes through it, and becomes higher in temperature heated as T ^, is cleaned of the deposited salts in the manner described and, after heating from the outside, is

00980870235 - 35—

by means of the steam in the spirals 36 in the spirals 36 * of the line B *, and «was together with the current xk- c6 k + i (which has already been described), which comes from the line B, so that a current z + i is formed. The current i + i flows through the spirals 36 * of the line B ¹ , is heated up to temperature T and is then fed into the brine line 39 * of the flash line B ¹ , which then becomes the brine line 39 of the flash line B, from which, as already mentioned, k aspirated and a current is fed to the brine line 40 of the flash line ¹ C.

The gate parts of the invention which can be obtained by means of the device and the method are for the person skilled in the art clearly apparent from the above description and the given implementation examples.

The technical details of the device and the method according to the invention can be modified or be further developed without thereby departing from the scope specified by the invention.

- Patent claims: -

009808/0235 " ⁵⁶ -

Claims (1)

Patent claims: 1. Device for heat exchange between liquids in the vapor phase, characterized in that the device (1, 30, 30 ^f , 30 ¹¹ ) has two columns connected in series (10, 11) through which the liquid can flow in countercurrent, the liquid in which one column is subjected to successive evaporation at different geometrical heights as a result of the decrease in hydrostatic pressure, and has devices (13, 15, 16) which serve to direct the vapor generated during each evaporation to the other column (10), in which it can be condensed * 2. Device according to claim 1, characterized in that that the two columns (10, 11) consist of a substantially vertically arranged tube (1) in which a partition (9) is arranged in the longitudinal direction of the tube, which has an opening (12) at its lower end, through which a stream of liquid can pass, and devices (13f 15, 16) at different levels has through which steam can be passed from one column to the other. 3. Device according to claim 1, characterized in that the two columns by two mutually con- - 37 -009808/0235 centrally arranged tubes (28, 29) are formed which are connected to one another at their lower ends and having devices (13, 17) at different heights through which steam from one to the other Column can be passed. 4. Device according to claim 1, characterized in that the two columns (10, 11) through the two Arms of a U-shaped bent tube (1) are formed and the two arms at different heights by devices (13, 17) are in communication with each other, through which steam is passed from one column to the other can be. 5. Device according to claims 1 to 4, characterized in that the devices which serve to direct the steam from one column to the other from plates (17) at different heights of the evaporator column (11) are arranged, and immediately below each one * a plate located connecting elements (13) exist, which the evaporator column with connect to the condenser column " 6. Device according to claim 5, characterized in that the plates (17) of the evaporator column are inclined with respect to the vertical at an angle U of less than 90 ^Ω. 009808/0235 " ³⁸ " 7. Device according to claim 5, characterized in that the plates (17) are formed substantially concave with respect to the vertical. 8. Device according to claim 7 »characterized in that the concave design of the plate is that one edge of the plate with respect to the ascent direction of the evaporating liquid one Has undercut (27). 9. Device according to claim 5, characterized in that the geometric axis of the connecting elements (13) at a greater height than the corresponding separation limit (19) between! Liquid and vapor which is assigned to each plate of the evaporator column is. 10. Device according to claims 5 and 9, characterized in that the connecting elements (13) consist of openings, pipes or corresponding flow devices. 11. Device according to one of claims 5-10, characterized in that on the inside of the capacitor column (10) and directly above the connecting elements (13) plates are arranged and in particular are inclined with respect to the vertical at an angle OC which is smaller than 90 °. 009808/0235 - 39 - 12. Device according to one of claims 5-11 * characterized in that the condenser column is provided with baffles, in particular in relation are inclined to the vertical at an angle A which is smaller than 90 °. 13. Device according to one of claims 5-12, characterized in that the evaporator column is provided with baffles, in particular in relation are inclined to the vertical at an angle> * ", which is smaller than 90 °. 14. Device according to one of claims 1-13, characterized in that the two columns at their upper ends each one under barometric pressure have standing arm (2, 3) and the two arms are connected via a hydraulic seal to vessels (6, 7), the free surfaces of which are on different Heights are to each other, with the level of the free surface of the barometric arm (2) of the Condenser column (10) connected vessel is located at a greater height. 15 «device according to one of claims 1-14, characterized in that in the inlet arm of the condenser column a pressure reducing system (8) and on the lowest point of the evaporator column a device 009808/0235 - 40 - (H) is arranged, which serves to supply sufficient heat so that the liquid on a little over the boiling temperature lying temperature can be brought, which corresponds to the pressure at the point in question. 16. Device according to one of claims 1-13 »thereby characterized in that at the lowest point of the facility there is a system for the delivery of solids is provided, which are precipitated from the liquid treated in the facility. 17. Process for the treatment of saline water and for the precipitation of the salts, their solubility with decreases with increasing temperature, characterized in that for this purpose the device according to one of the claims 1 to 16 is used. 18. A method for heat exchange between liquids in the vapor phase, characterized in that a device according to one of claims 1 to 17 is used .. 19. The method according to claim 18, characterized in, that a liquid in the device is circulated from the inlet to the outlet so that a) the temperature of the liquid in the condenser column at each point slightly below the boiling point 009808/0235 -41- is due to the pressure at this point geometric height, and the liquid passing through the column on its passage as a result of the condensation occurring in it, the steam supplied by the steam column is heated, b) the temperature of the liquid in the evaporator column at each point slightly above the boiling point which corresponds to the bridge at this point due to the geometric height, and which by the Liquid passing through the column on its passage due to the successive evaporations is cooled, c) at a certain height of the evaporator column a slightly higher temperature than the same height prevails in the condenser column and the outlet temperature of the liquid emerging from the system is consequently higher than the inlet temperature, where the difference in heat content is obviously equal to the heat which has been introduced into the system at the inlet point, the deepest point. 20. Establishment and procedure which essentially correspond to the description and the exemplary embodiments and used for the stated purposes. 009808/0235