DD271939A1 - INJECTION COOLER FOR HOT STEAM LINE - Google Patents

Abstract

Injection cooler for hot steam pipes, which has several separately switchable Duesengruppen, which are arranged perpendicular to the steam flow and connected to a control and shut-off valve having injection water line. The Duesenstoecke receiving the Duesengruppen are - preferably mounted in a plane - firmly connected. The cross section of the nozzle groups is increasing according to a given numerical ratio, preferably according to the dual power series 2n, where n stands as a symbol for integer natural numbers from 0 to. By selective switching on and off of nozzle groups with the aid of valves located in the branches of the injection water line leading to the nozzle groups, graduated amounts of injection water can be adjusted uniformly. Fig. 1

Description

For this 2 pages drawings

Application of the invention

The invention relates to an injection cooler for superheated steam lines, which serves for adjusting the temperature of the flowing steam.

Characteristic of the known state of the art

Systems using steam as an energy source are calculated to operate with steam at a certain temperature and pressure. In general, the steam supplied from the boiler is overheated, so that the apparatus using the steam energy can absorb the steam at a higher temperature than required. In order to maintain the desired temperature conditions, it is common practice to reduce the superheated steam to a low temperature through a superheated steam cooler. The superheated steam cooler is inserted into a steam line and injects cooling water into it.

For effective control of the temperature of the steam mvihrore requirements are placed on the operation of the steam boilers.

These requirements must be fulfilled at the same time. An important requirement is that the amount of cooling water supplied to the steam line must be accurately controlled. It is obvious that if too much or too little cooling water the steam tempera ture can not be kept exactly. Another important requirement is that the cooling water is injected into the steam line in a mold that facilitates its vaporization. If the cooling water does not snow! evaporates, it accumulates at the bottom of the steam line and evaporates in a more or less uncontrolled manner. This makes an exact adjustment of the steam temperature almost impossible. Another important requirement is that the cooling water in the steam line is distributed in a generally uniform pattern, so that the steam temperature is uniformly reduced.

A superheated steam cooler of the type referred to as eir.gtings for spraying a high-pressure liquid as a spray into a vapor stream is known from Swiss Patent 62947. This superheated steam cooler contains a spray tube. In this spray nozzles distributed in the longitudinal and circumferential directions are arranged at a mutual distance. These spray nozzles are obviously smooth cylindrical. In the spray tube a spool is slidably mounted. When moving the spray nozzles have been opened and closed in different numbers.

Also known is a superheated steam cooler in which a serving for supplying the cooling water pipe is arranged centrally in the steam channel (DE-AS 1151520). At the end of this pipe is closed. On its last piece it has in the circumferential direction advantageous and in »a longitudinal offset outlet opening for the cooling water. An outlet closing and releasing sleeve can be moved over the last piece of this tube. From GB-PS 1151016 a hot steam cooler with a single spray nozzle is known. The spray nozzle consists of a cylindrical vortex chamber, followed by downstream of a downstream in the flow direction tapered section. At the radial distance from the vortex chamber an annular chamber is arranged, the rr. it is the vortex chamber through tangential in

this opening feed channels is connected. The feed channels are helically distributed and are successively opened and closed by a control-actuated slider. The supply of the

Liquid enters the annular chamber through a single uncontrolled port. A similar solution is the subject of DE-PS 2754559. Movable pistons and sleeves on the nozzle sticks are constantly

exposed to high temperatures and relatively susceptible to interference.

A solution is also known in which the nozzle assembly contains two identical nozzle groups which can be disconnected and switched on (SU 992902). Also known are solutions that provide a separate fine and coarse injection in a mixing tube (DE 412033). For this purpose, it is also known to arrange two nozzle sticks with different cross sections in a mixing tube

(Danilov, S.N., u.a .: Regulation of the temperature of the 2-fold superheated steam during start-up of the 500 MW block, electr.

stancii (Moscow), 53 (1982) 10, pp. 23-25).

In a known Reraelelaturatur with water injection in the throttle body are two nozzles via separate lines

supplied, in each of which arranged in shunt switching and / or control valves are located, which are digitally controllable (DE 3339477); By summing individual valve cross sections, injection water flows into the two lines

Achieve gradations. The pressure atomizing nozzles in the injection coolers are designed for maximum throughput. This means that bsi

highest cooling water pressure in front of the nozzle sets the maximum atomizer quality. The amount of water to be injected must be accurately metered according to the load or operating state. Since the spraying of the water is only possible from a certain overpressure, this dosage is only applicable to a lower minimum limit. There, where very small

Injection water quantities are needed, for. B. in the starting operation of steam boilers, therefore, a special start-up Injection are provided. These Anfizeinspritzungen have the disadvantage that they are in full load - so most Time - uncooled and thus exposed to increased wear, so that their function is questioned when operated

should be.

• Object of the invention

The aim of the invention is an injection cooler, the low-wear in steam systems from start-up to full load point can be used and allows in this entire area the spraying accurately metered injection water quantities.

Explanation of the essence of the invention

The invention has for its object to meet the objective of creating an injection cooler with several separate ei.ischaltbaron Düsengruppsn, which are arranged and dimensioned in their cross-section so that their combination allows the injection evenly graduated injection water quantities, wherein in the operating case of the maximum injection water demand all nozzle groups involved in the injection and thus are sufficiently cooled. According to the invention nozzle groups are the nozzle groups in a plane mounted and preferably mechanically firmly connected so that there is no mutual interference. The cross section of the nozzle groups is carried out in such ascending order according to a given numerical ratio, preferably according to the dual power series 2 ", in which η integer natural numbers from 0 to + means that by selectively turning on and off of nozzle groups by means of in The nozzle groups sensing branches of the injection water line lying shut-off valves evenly graduated injection water quantities are adjustable.

In a further embodiment of the invention, the fittings, which are in the leading to the smallest cross-sections nozzle groups branches of the injection water line are formed as throttle valves. Thus, in addition to the respective mass flow adapted sensitive throttling possibility is achieved, so that a fine metering smallest Einspritzrnengen is given in the start-up operation at Aufrochterhaltung the spray effect. The combination of the nozzle groups is chosen so that in case of operation of the maximum injection water demand all nozzles are in operation and thus cooled. The injection quantity can be influenced in this operating case in a known manner by the common control valve in the injection water line.

Suitably, when equipped with two nozzle groups of the injection cooler on a single nozzle, which has between the nozzle groups a blind and opposite connections for the branch line. When equipped with two nozzle sticks and more than two nozzle groups, the nozzle sticks are at an angle to each other, preferably T-shaped, arranged and the Düsengruppan separated by blinds. However, the mechanically fixed connection of the nozzle blocks with each other is not absolutely necessary.

With higher-flow injection coolers, the possibility of getting along completely without throttling is given due to the increasing number of volume gradations, ζ. B. at low Druckg6fälle between water and steam. Thus, with a 4-flow design and the associated ratio of the cross-sections 1: 2: 4: 8, the number of possible injection quantities would increase to 15.

The invention has the advantage that with the injection cooler all conceivable operating cases from the smallest to the maximum injection quantity without affecting the spray effect at the most accurate dosing are gentle on the material and low wear.

The detailed explanation is based on the drawing. Fig. 1 shows an injection cooler in two views with the associated connections to the injection water line and Fig.2 a Characteristic field of the injection quantities. According to Fig. 1 in the mixing tube 1 and the protective tube 2 T-shaped arranged three nozzle sticks 3 to 5 on the Branch lines S; 9; 10 with the on: ritzwasserleitung 6 connected, in which the control valve 7 is located. The two Branch lines 8; 9 are each with a control valve 11; 12 and the third branch line 10 is provided with a shut-off valve 13

fitted. Severance payments 14; 15 Xn the nozzle sticks from each other, so that a 3flutige injection arises.

The cross section of the nozzle sticks behave according to the dual series 1: 2: 4. The nozzle groups in the Nozzle sticks thus have the corresponding different number of nozzles. The mode of action is the following: When opening the Regolarmatur 7 is injection water to the fittings 11; 12; 13 on. If valve 11 is opened, it receives Nozzle group 3 water over the branch line 8 and opritzt according to the smallest cross-section of the

Lowest possible Wassarmenge Mi (Fig.2) on (start injection). The next larger injection quantity M ₂ is by sole

Opening of valve 12 to achieve with the valve 11 closed. This is followed by amount M ₃ by opening the valves 11; 12

while armature 13 is closed. By opening the valve 13 alone, the quantity M _{4 is} injected via the branch line 10. Up to the maximum amount M ₇ can be so gradually all intermediate quantities by selective switching off and on of the valves 11; 12; Reach 13.

The fine adjustment for quantities between stages is carried out by throttling; in load operation by the control valve 7 in the Injection water line 6 ur dim start or. Low load operated by fitting 11 and / or 12. Did you want z. B. Mer M ^ ₁ alone achieve by throttling the pressure without switching off nozzle groups, would have

one Fia i under 5% of the pressure go, which hardly alone with a control valve 7 in the injection water pipe 6

to achieve (pressing) and would lead to the loss of the spray effect.

Claims (4)

1. injection cooler for superheated steam lines having a plurality of separately switchable nozzle groups, which are arranged perpendicular to the steam flow and connected to a regular and Absperraramtur injection water line, characterized in that the nozzle groups receiving nozzle sticks (3 to 5) mounted in a plane and are mechanically fixedly connected to one another and the cross-section of the nozzle groups is made increasing according to a given numerical ratio, preferably according to the dual power series 2 ", in which η is a symbol for integer natural numbers from 0 to +, such that by selective selection and shutdown of nozzle groups by means of in the leading to the nozzle groups branches (9 to 10) of the injection water line (6) fittings (11 to 13) uniformly graduated injection water quantities (M ₁ to M _n ) are adjustable. 2. Injection cooler according to claim 1, characterized in that the valves (11; 12) are at least the branches of the injection water conduit leading to the nozzle groups having the smallest cross sections, (8; 9) being designed as throttle valves. 3. Injection cooler according to claim 1, characterized in that when equipped with two nozzle groups, a single nozzle block is provided which has a blinding (14) between the nozzle groups. 4. Injection cooler according to claim 1, characterized in that when equipped with two nozzle sticks, this T-shaped attached and the nozzle groups from each other by Abblindungon (14; 15) are separated.