FI79790B - FOERFARANDE FOER MINSKANDE AV FOERBRUKNINGEN AV MATARVATTEN I DESTILLATIONSANORDNINGAR MED FLERA STEG ELLER KOLONNBASERADE GENERATORER FOER REN ACHGA ORORDNING FOER GENOMFOERANDE AV FOERFARANDET. - Google Patents

Description

79790 Ί Method for reducing feedwater consumption in multi-stage ordering equipment or column-based pure steam generators and apparatus for carrying out the method is a method for reducing feed water consumption in multi - stage distillation equipment or column - based clean steam generators.

The invention also relates to a device for reducing the consumption of feed water in multi-stage distillation devices or column-based clean steam generators.

Currently known multi-stage distillation equipment or column-based pure steam generators operate on the principle that the feed water 20 must be in excess of about 10%. In this case, we are talking about an overflow of 10%. If softened water is used as feed water, the overflow can be up to 30%.

In all known solutions according to the prior art, said overflow is considered necessary, because in the absence of overflow, the combustion of impurities in the columns or column-based pure steam generators of the multi-stage distillation apparatus would result. This would also result in a significant reduction in heat exchange.

It is an object of the invention to provide a method for reducing feed water consumption in multi-stage distillation equipment or column-based clean steam generators.

The objects of the invention are achieved by a method which is mainly characterized in that the dirty bottom stream of the last column of a multi-stage distillation apparatus or of a single column of a collector-based pure steam generator is divided into two substreams, the first 2,79790 along one to a sewer or the like.

It is also an object of the invention to provide a device which makes it possible to reduce the consumption of feed water in multi-stage distillation devices or column-based clean steam generators.

The apparatus according to the invention, in turn, is essentially characterized in that a space for discharging the dirty bottom stream of the last column of the multi-stage distillation apparatus or the only column of the column-based pure steam generator is arranged in which the dirty bottom stream is arranged to flow and said first outlet, the outlet connection is adapted to return part of the dirty bottom stream 15 back to the supply water flow line and the second outlet connection is adapted to lead part of the dirty bottom stream to a sewer or the like.

The method and apparatus of the invention provide the significant advantage that the feedwater overflow can be reduced from about 10% to about 2% if the outlet connections are sized so that the first outlet is adapted to return about 3/4 of the total dirty bottom stream back from the dirty bottom stream. and the second outlet is adapted to remove about 1/4 of the dirty bottom stream from the drain or the like.

Reducing the feed water overflow to about 2% according to the invention naturally causes the feed water to become dirty. However, this does not pose any problem, as the distillation machine or the clean steam generator can also handle the supply of slightly dirty feed water. The main advantage is that reducing the total overflow from about 10% to about 2% results in significant savings in expensive feedwater. The solution according to the invention naturally causes a slight rise in temperature, but the rise in temperature is very small and has no detrimental effect on the operation of the multi-stage distillation apparatus or the column-based pure steam generator.

3,79790 1 The invention will be explained in detail with reference to some preferred embodiments of the invention shown in the figures of the accompanying drawings, to which, however, the invention is not intended to be exclusively limited.

Figure 1 schematically shows a multi-stage distillation apparatus.

Fig. 2 shows the last column of the multi-stage distillation apparatus according to Fig. 1 and the dirty bottom stream outlet solution of the last column.

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Figure 3 shows a detail of Figure 2 on a larger scale.

Figure 4 shows a detail of Figure 2 on a larger scale of another preferred embodiment.

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In the embodiment of Figure 1, the multi-stage distillation apparatus is generally indicated by reference numeral 10. In this embodiment, the distillation apparatus 10 comprises four stages, i.e. first stage 11, second stage 12, third stage 13 and fourth stage 14. Reference numeral 20 15 denotes feed water flow line and reference number 16 factory steam supply line. The non-evaporating portion of the water to be distilled is passed from the first column 11 along line 17 to the second column 12, from the second column 12 along line 18 to the third column 13 and from column 13 along line 19 to the fourth column 14. The dirty bottom stream of the last column 14 25 is discharged along the outlet 20. The condensing steam condensate is removed along line 21. The distillate can be discharged from each column 11-14 separately or as shown in Figure 1 by passing the distillate e.g. from columns 12, 13 and 14 along lines 22, 23 and 24 to a collection line 25 along which the distillate is led to a distillate collection space 26. Tis-30 the outlet from the collecting distillate 26 is indicated by reference numeral 27.

The multi-stage distillation apparatus shown in Figure 1 represents a distillation apparatus currently in common use. If the distillate is taken out at 1000 kg per hour, in order to achieve an overflow of 10%, the feed water flow must be 1100 kg per hour, whereby the amount of dirty bottom flow is 100 kg per hour.

4,79790 1 According to the basic invention, as shown in Fig. 2, the dirty bottom stream of the last column 14 of the distillation apparatus 10 is led along the outlet 20 to a space 28 provided with a first outlet 29 and a second outlet 30. Part of the dirty bottom stream 5 is returned to the feed line 15 29 as the first partial flow A and only a small part is led to the sewer along the second discharge line 30 as the second partial flow B.

The situation according to Figure 2 can be illustrated by the following pre-10 character examination. If the feed water is fed, for example, 1000 liters and the feed water contains 1000 units of impurities. In this case, 980 liters of distillate are obtained from line 24, which contains 0 units of impurities. Outlet 20 provides 80 liters of dirty bottom stream, which flows into space 28. Dirty bottom stream contains 4,000 units of impurities. When 3/4 of the dirty bottom stream is returned along the first 15 outlet 29 and 1/4 of the dirty bottom stream is discharged to the sewer along the second outlet line 30, 60 liters of dirty bottom stream containing 3,000 units of impurities and 20 liters of dirty bottom stream containing impurities of 1000 yk-20 individuals. In the supply line 15, then 1060 liters of contaminated feed water flow and this amount of feed water contains 4000 units of impurities. Thus, in the manner according to the invention, it is possible to reduce the commonly used 10% overflow to a value as low as 2%.

In the embodiment of Figure 3, the first outlet 29 and the second outlet 30 are formed by pipes of the same diameter. The first outlet 29 is provided with holes 29a and the second outlet 30 is provided with holes 30a. The ratio of the holes 29a and 30a is e.g. such that the partial flow A along the outlet connection 29 is 3/4 and the partial flow B along the outlet connection 30 30 is 1/4.

In the embodiment of Figure 4, the corresponding flow ratio between the first outlet 29 and the second outlet 30 is obtained by dimensioning the non-perforated tubes 29 and 30 so that the cross-sectional area α1 of the tube 29 is 3/4 and the cross-sectional area α1 of the tube 30 is 1. / 4. The embodiments shown in Figures 2 to 4 can be implemented in a similar manner in column-based pure steam generators, in which the last column 14 of the distillation apparatus 10 corresponds to the only column of the pure steam generator. Since such an embodiment will be obvious to a person skilled in the art, it will not be described in more detail.

Only some preferred embodiments of the invention have been described above, and it will be apparent to those skilled in the art that numerous modifications may be made thereto within the scope of the inventive idea set forth in the appended claims.

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Claims (8)

A method for reducing feed water consumption in multi-stage distillation units or column-based clean steam generators, characterized in that the dirty bottom stream of the last column (14) of the multi-stage distillation unit (10) or the column-based pure steam generator single-column outlet (20) of which the first partial flow (A) is led along the first connection (29) to the supply water supply line (15) and the second partial flow (B) Ί0 is led along the second connection (30) to a sewer or the like. 1 Claims Method according to Claim 1, characterized in that the first partial flow (A) is greater than the second partial flow (B). Method according to Claim 2, characterized in that a ratio of 3/4: 1/4 is used as the ratio of the first partial flow (A) to the second partial flow (B). Apparatus for reducing feed water consumption in multi-stage distillation-20 equipment or column-based clean steam generators, characterized in that the dirty bottom stream space (20) of the last column (14) of the multi-stage distillation unit (10) or the only column of the column-based clean steam generator is , in which the dirty bottom stream is adapted to flow and that two outlet connections (29, 30) are arranged in said space (28), of which the first outlet connection (29) is adapted to return part of the dirty bottom stream back to the feed water flow line (15) and the second outlet connection (30) is adapted to conduct part of the dirty bottom current to a sewer or the like. 30 Device according to claim 4, characterized in that the outlet connections (29, 30) arranged in said space (28) are torn pipes (29, 29a; 30, 30a). Device according to Claim 5, characterized in that the ratio of the diameters of the holes (29a) of the first outlet connection (29) and the holes (30a) of the second outlet connection (30) is 3/4: 1/4. 7 79790 6 79790 Device according to claim 4, characterized in that the outlet connections (29, 30) arranged in said space (28) are pipes of different diameters. Device according to Claim 7, characterized in that the ratio of the cross-sectional area ap of the first outlet connection (29) to the cross-sectional area (α 2) of the second outlet connection (30) is 3/4: 1/4. 35 8 79790