GB2129110A - Condenser - Google Patents

Abstract

In a condenser, particularly for superheated steam, having water spray means 3, a precooling section 2 of a pipe coil 1 carries baffles 8 for separating moisture from air flowing up over the coil, thereby reducing the height of the condenser as compared with known arrangements in which such baffles were provided on a separate support. <IMAGE>

Description

SPECIFICATION Condenser The invention relates to condensers, particularly but not exclusively for cooling superheated steam used in a refrigeration system. An important part of such a system is the condenser where the heat won from the evaporator is transferred to the environment, by cooling the superheated steam into the saturated steam state and then condensing the saturated steam.

Known condensers for super-heated steam comprise a pipe coil for carrying the steam, means for spraying cooling water on the pipe coil, and means for creating a flow of cooling air over the coil. In fact the super-heated steam must first be cooled to some extent before it enters the water cooling region, and this pre-cooling is carried out in a pre-cooling section of the pipe coil provided with external cooling ribs, above the water spraying means. In addition a unit provided with baffles is provided above the water spraying means for extracting moisture from the said cooling air flow. The provision of the separate precooling section of the pipe coil and the baffle unit increases the height of the condenser, and also creates resistance to the cooling air flow and thus decreases efficiency.

According to the present invention there is provided a condenser comprising a pipe coil for carrying fluid to be condensed, and means for spraying cooling water on said pipe coil, wherein a pre-cooling section of said pipe coil carries external baffles arranged to line in the path of flow of cooling air over the pipe coil and, by deflection of said flow, to cause moisture to be separated therefrom.

With such an arrangement the pre-cooling section of the pipe coil is effectively combined with the aforementioned baffle unit, the baffles taking the place of the ribs previously provided on the pre-cooling section, whereby the height of condenser may be reduced and flow resistance decreased, giving greater efficiency and lower production costs. Furthermore the said baffles may be formed with a larger surface area than the conventional ribs, so as to collect a larger amount of moisture to pre-cool the steam more efficiently.

It is advantageous to form the said baffles as lamellas arranged parallel to one another. They may be of sinuous form, or consist of two flat plates arranged at an angle of not more than 600 to the axis of the pipe, or consist of three flat plates arranged in an elongate Z shape.

In one embodiment the said baffles are located at the same level as the water spraying means.

Some embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, wherein Fig. 1 is a diagrammatic front view of a traditionally constructed condenser; Fig. 2 is a similar view of a condenser according to a first embodiment of the present invention; Fig. 3 is a side view of the condenser of Fig. 2; Fig. 4 is a side view of another embodiment; Figs. 5, 6 and 7 show alternative forms of baffle; Fig. 8 is a cross-section of one embodiment of the pipe of the steam pre-cooler; and Fig. 9 is a cross-section of another form of the pipe.

In a traditionally constructed condenser as shown in Fig. 1 condensing pipe coil 1 is connected with a steam pre-cooler 2 having outer ribs in the form of flat discs. Between the pipe coil 1 and the steam pre-cooler 2 a water spraying unit 3 and a unit 7 for collecting moisture from air into droplets are arranged. The air is made to flow by an exhauster 4 with a propeller. The water sprayed by the water sprayer unit 3 is collected in a tank 5, from which a circulating pump 6 takes it out.

The superheated steam enters the condenser at point A. This team is produced for example from an ammonia plant and flows through the steam pre-cooler 2 and the pipe coil 1 and leaves the condenser at point B as liquid.

The water to be sprayed enters the condenser at point C, and from sprayers of the unit 3 falls onto the surface of the pipe coil 1, and therefrom to the tank 5. The condenser built up in such a way has a height H1.

Referring now to Figs. 2 and 3, the steam precooler 2 is arranged above a pipe coil 1 and between the water sprayer units 3. The steam precooler 2 is equipped with baffles 8 shaped to deflect the flow of air made to move by the exhauster 4 and to collect moisture therefrom. In this way the height H, of the known condenser can be decreased to a height H2.

The steam pre-cooler 2 comprises a pipe in which in known way inner ribs are arranged. In the plane of the inner ribs the pipe has the crosssection shown in Fig. 8 or Fig. 9.

As shown in Fig. 2, the baffles 8 are shaped so as to ensure a change of direction of the air-steam caused by exhauster 4. In this way moisture carried in the air stream can be separated from it more effectively than by the outer ribs 8 shaped as flat discs. Some of the droplets running down are evaporated and in this way the heat transfer effect of the cooler is improved, the convective heat exchange being joined by evaporative effect. The baffles 8 are arranged between the water sprayer units 3, in the same plane as the latter.

As shown in Fig. 4, the baffles 8 of the steam pre-cooler 2 can alternatively be placed directly over the water spraying units 3. This embodiment also decreases the height of the condenser in comparison with known apparatus.

Figs. 5, 6 and 7 show different embodiments of baffles 8 shaped as lamellas 9. Sinuous lamellas are shown in Fig. 5, straight wing-like lamellas in Fig. 6, and Z-letter-form lamellas in Fig. 7.

Preferably the angle between the wings as shown in Fig. 6 is not greater than 1200, and the wings are arranged symmetrically to the axis of the pipe.

It can be seen from the drawings that the steam pre-cooler can be arranged without difficulty in the upper part of the condenser. Through the use of the proposed steam pre-cooler cooling of the superheated steam can be effected better than in the known apparatus and it is possible to omit from the condenser the unit 7 for separating moisture from the air. The present invention makes it possible to produce condensers with smaller height and, through this, to reduce costs of construction.

Claims (10)

1. A condenser comprising a pipe coil for carrying fluid to be condensed, and means for spraying cooling water on said pipe coil, wherein a pre-cooling section of said pipe coil carries external baffles arranged to lie in the path of flow of cooling air over the pipe coil and, by deflection of said flow, to cause moisture to be separated therefrom.

2. A condenser as claimed in claim 1, wherein said pipe coil also has internal baffles to assist in cooling said fluid.

3. A condenser as claimed in claim 1 or2, wherein the said external baffles comprise lamellas arranged parallel to one another.

4. A condenser as claimed in claim 3, wherein the lamellas are of sinuous form.

5. A condenser as claimed in claim 3, wherein the lamellas each consist of two flat plates arranged at an angle of not more than 60 to the pipe axis.

6. A condenser as claimed in claim 3, wherein the lamellas each consist of three flat plates arranged in an elongate Z shape.

7. A condenser as claimed in any of the preceding claims, wherein the said baffles are located at the same level as said water spraying means.

8. A condenser as claimed in any of claims 1 to 6, wherein the said baffles are located directly above said water spraying means.

9. A condenser as claimed in any of the preceding claims, which is particularly adapted for condensing super-heated steam.

10. Condensers substantially as hereinbefore described with reference to Figures 2 to 9 of the accompanying drawings.