DE2020580B2 - DEVICE FOR RELAXING DISTILLATION - Google Patents

Description

30th

The invention relates to a device for flash distillation, in particular from seawater, with one or more, optionally connected in series Expansion chambers each with at least one inlet, built-in, curved Guide surfaces for the liquid, at least one outlet for the non-evaporated liquid and devices to condense and draw off the evaporated liquid.

The expansion evaporator of this type known from BE-PS 7 09 702 has a large number of in one Housing with a continuous horizontal floor arranged side by side, each with partitions separate expansion chambers, which are connected to each other by underneath the partition walls the entire width of the chamber are connected through openings and each also via the so full chamber width continuous, weir-like guide web and, if necessary, one on the partition have at a distance above the floor arranged horizontal guide web, wherein the liquid through the channel formed between the floor and the horizontal guide post via the weir-like guide web away into one between this and the partition wall to the subsequent expansion chamber formed storage space is directed. However, this known construction leads to an undesirable one partial nebulization of the liquid on the partitions and also does not allow effective Redeployment of the liquid.

The expansion evaporator described in DT-AS 11 91 787 also has a large number of in one housing with a continuous, horizontal Relaxation chambers arranged next to each other on the floor, each separated by partition walls, which are spaced over each other by each under one at the lower end of the partition wall the bottom substantially horizontally extending plate with upturned ends extending connecting channels are connected and, if necessary, each one serving to collect the sprayed liquid, Have obliquely downward guide plate. Even with this construction, none will be effective Reallocation of liquid achieved.

The expansion evaporator according to US-PS 31 92 132 in turn has a plurality of in one joint housing arranged next to each other, separated by partition walls from each other expansion chambers, each of which communicates with one another through openings in the partition walls arranged on the floor, with each expansion chamber one with a weir-like vertical partition and one with openings on top of it Top wall formed, in operation completely filled with liquid inlet space is divided off which the liquid flows out through the openings in a thin layer As in this known device the liquid in each case from a relaxation chamber horizontally into the completely filled with liquid and the inlet space of the subsequent expansion chamber, which is largely closed at the top, passes over and overflows through the openings through the partition wall into a collecting space, is by far the largest Proportion of the liquid in the expansion chambers the evaporation through the static Pressure of the liquid above is largely suppressed, so that the lower one overheats Liquid layers and sudden evaporation phenomena when the liquid emerges through the openings of the inlet space and a resulting partial nebulization of the liquid comes

The object of the invention is now to provide a device for the expansion distillation of the aforementioned Art to create an effective one with simple means without mechanically moving devices Redistribution of the liquid in the expansion chamber ensures and that by the static pressure of the Liquid induced suppression of evaporation reduces or avoids and an effective utilization the temperature difference resulting from the pressure difference between several expansion chambers allowed for evaporation.

To solve this problem, the device for flash distillation of the type mentioned according to the invention characterized in that

a) each expansion chamber is inclined from the inlet to one or more discharge lines Has soil,

b) in each expansion chamber on the inclined floor a plurality of baffles in rows is arranged offset to each other on a gap.

c) the baffles each at an angle inclined to the inlet with the outlets connecting, imaginary flow direction and

d) each baffle plate a liquid flowing down, exchanging the upper and lower ones Has curved deflecting surfaces surrounding liquid layers.

Due to the inclined design of the bottom of the expansion chamber and the curved deflection

surfaces of the baffle plates is even with a reduction the amount of liquid introduced improves the flow movement and an effective exchange of the upper and causes lower layers of the liquid, so that without creating a large flow resistance The extent of overheating in deeper layers of the liquid is largely reduced, and so is evaporation and the temperature difference resulting from the pressure difference between the expansion chambers is effectively used.

For the sake of simplicity, the distillation apparatus is herein essentially referred to with reference to FIG Described evaporation of sea water. However, it is equally suitable for flash distillation other liquids, with regard to the inclination of the bottom as well as the arrangement, the shape and the dimensions of the baffle plates of the liquid to be distilled and the other boundary conditions is adjusted. In particular, several expansion chambers can also be connected in series and these are operated with gradually decreasing pressure.

In the following, preferred embodiments of the distillation device are based on the drawings further explained. It shows

F i g. 1 is a schematic partial plan view of the floor of an expansion chamber, which is covered with baffle plates,

F i g. FIG. 2 is a schematic side view of the FIG. 1 illustrated bottom of the expansion chamber,

F i g. 3 is a schematic view of a still and

F i g. 4 is a schematic view of a multi-stage still.

The figure! and 2 show only the one for the flowing Liquid required lower section of a relaxation chamber 2 for a seawater distillation plant, the devices used to preheat the liquid and condense the vapor are omitted. The liquid to be distilled 4 is through an inlet line 1 in the Relaxation chamber 2 introduced and the still residue discharged through drains 5. On the The bottom 7 of the expansion chamber 2 is a plurality of baffle plates 6 in several rows each arranged offset to one another with a gap. Like F i g. 1 shows, the baffles each run under one Angle of about 45 ° obliquely to that connecting the inlet line 1 with the discharge lines 5, imaginary Direction of flow. Each baffle plate € is curved and has a curved one on its inside Deflection surface 8, which the flowing liquid in the in F i g. 2 indicated way deflects.

The liquid introduced through the inlet line 1 into the interior 3 of the expansion chamber 2 is deflected when striking the curved deflection surfaces 8 of the deflection plates 6 of the first row that the lower liquid layers are shifted upwards and the upper liquid layers are shifted downwards will. In the subsequent rows of deflection slits 6, the liquid is again in the redeployed in the manner described. The dimensions, the curvature, the angular arrangement and the distribution of the baffles are · ίΐ; "the size of the Relaxation chamber 2, the fluid rings and the other boundary conditions are appropriately coordinated.

In the case of the FIG. 3 is fed by means of a feed pump 12 driven by a motor 13 via a suction line 11 and a supply line 14, seawater into the condenser tubes 16 arranged in a desolation chamber 15 and a heater 18 is supplied to the expansion chamber 15. This has an inclined floor 19 which slopes down from the inlet to a residue container 21 and is covered with a plurality of baffle plates 20 which give the sea water an additional movement. The height difference h corresponding to the inclination of the bottom 19 is selected, taking into account the shape of the baffle plates 20 and the properties of the sea water and the physical conditions in the expansion chamber 15, so that the liquid has a shifting movement sufficient to reduce the degree of overheating; is granted. The salt water that collects in the residue container 21 is drawn off via discharge lines 22 and 24 by means of a drainage pump 23 driven by a motor 25. The steam generated in the expansion chamber 15 is condensed through the condenser tubes 16 and the condensate collected in a fresh water trough 26 is discharged through a compartment 27 by means of a pump 28 driven by a motor 30 via a discharge line 29. In the fresh water trough 26, deflection plates 31 are also arranged.

The seawater heated as it flows through the condenser tubes 16 and the heating device: 18 flows after its introduction into the expansion chamber 15 due to the inclination of the bottom 19 with high Speed against the baffles 20, which give the water a redeployment movement during evaporation and cause a reduction in the degree of overheating.

In the case of the FIG. 4 are two expansion chambers 15 'and 15 of the embodiment shown in FIG. 3 connected in series, the sea water exiting from the condenser tubes 16 of the expansion chamber 15, however, being introduced into the expansion chamber 15 'via a line 17, the condenser tubes 16' and the inlet line 17 ', and that from the residue container 21' of the expansion chamber 15 ' withdrawn distillation residue is introduced into the downstream expansion chamber 15 by means of a pump 23 'driven by a motor 25' via the lines 22 'and 24'. In a corresponding manner, the water that collects in the fresh water trough 26 'is fed into the fresh water trough 26 of the downstream expansion chamber 15 by means of a pump 28' driven by a motor 30 'via connecting lines 27' and 29 '. Since the expansion chambers 15 'and 15 are identical in terms of construction and mode of operation, with only the expansion chamber 15' being operated at a higher temperature, the individual parts of both devices have been given the same reference numerals, the parts of the in FIG. 4 relaxation chamber 15 'shown on the left were each identified by the addition of a superscript. The heights Λ and h ' decisive for the inclination of the floors 19 or 1!)' Are again selected taking into account the respective boundary conditions. The condenser tubes 16 and 16 'and the fresh water troughs 26 and 26' are inclined under the same V / inkel as the bottoms 19 and 19 ', so that the steam generated

Conditions for vapor-water separation at any point on the flowing liquid surface and the steam paths are also the same. However, depending on the requirements, the deflection plates 31 In the fresh water trough 26 and / or the condenser tubes 16 and the fresh water trough 26 are omitted be arranged horizontally or at a different incline, if this is due to the construction of the Relaxation chamber 15, the degree of utilization of the heat on the fresh water side or the permissible Concentration of the fresh water is desirable.

For this purpose 3 sheets of drawings

5

Claims (1)

Claim: Device for flash distillation, in particular of sea water, with one or more, If necessary, relaxation chambers connected one behind the other each with at least one inlet, built-in, curved guide surfaces for the Liquid, at least one outlet for the non-evaporated liquid and devices for Condensation and removal of the evaporated liquid, characterized in that a) each expansion chamber (2, 15) one from the inlet (1, 17) to one or more Has discharges (5, 22) sloping sloping floor (7, 19), b) in each expansion chamber (2, 15) on the inclined floor (7, 19) a plurality of Deflection plates (6, 20) are arranged in rows offset from one another with a gap, c) the baffles (6, 20) each under one Angle inclined to the imaginary connecting the inlet (1,17) with the outlets (5, 22) Direction of flow and d) each baffle plate (6, 20) one flowing down Liquid with the exchange of the upper and lower liquid layers (Fig. 2) shifting, has curved deflection surface (8).