JP2014062664A - Steam generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steam generator which enables easy control even when a water separator in the steam generator is composed of multiple tanks.SOLUTION: A steam generator 1 comprises: a tank part 2 including multiple evaporation tanks 21 and a collection tank 22 storing water which is not evaporated in the multiple evaporation tanks 21; tubes 25 through which hot water circulates, the tubes 25 being respectively disposed in the evaporation tanks 21 extending in a horizontal direction; a hot water supply line L1 which supplies the hot water to the tubes 25; a hot water discharge line L2 which discharges the hot water from the tubes 25; spray nozzles 23 disposed in the respective evaporation tanks 21 and spraying the water to the tubes 25; steam lead out parts 24 which lead out steam generated in the evaporation tanks 21; a spray water supply line L4 which supplies the water stored in the collection tank 22 to the spray nozzles 23; and a spray water supply pump 7 which is provided in the spray water supply line L4.

Description

  The present invention relates to a steam generator.

  Conventionally, boilers that boil fuel and boil water are widely used as steam generators. On the other hand, in order to be able to efficiently recover the energy of exhaust heat generated in factories and the like, a highly energy efficient steam generator that can generate steam without using fuel has been proposed (for example, , See Patent Document 1). According to the steam generator described in Patent Document 1, steam can be taken out from hot water having a relatively low temperature of about 90 ° C.

  As such a steam generator capable of taking out steam from hot water having a relatively low temperature, a shell and tube type steam / water separator including a tank and a tube arranged to penetrate the inside of the tank is provided. A steam generation apparatus using the above is also known. If a shell and tube type steam separator is used, for example, jacket cooling water (about 91 ° C.) of a gas engine is circulated through the tube as a heat source, and hot water of about 82 ° C. is sprayed on the tube inside the tank. Thus, it is possible to generate steam at the same time as the generator is driven by the gas engine. In this case, by forming a thin liquid film on the surface of the tube, steam can be generated even if the difference between the heat source circulating in the tube and the temperature of the sprayed water is relatively small at about 9 ° C. . Of the water sprayed on the tube, the water that has not become steam is stored in the lower part of the tank.

JP 2010-164223 A

  By the way, if the tank in the steam generator becomes large, the management cost for installation delivery, performance inspection, and the like becomes large. Therefore, the tank may be composed of a plurality of small tanks. However, in such a configuration, the amount of water stored in the lower part of the steam-water separator that does not become steam out of the water sprayed on the tube in the steam-water separator differs in each tank. It has been a problem that the maintenance of these waters becomes complicated.

  The present invention has been invented in view of the above problems, and provides a steam generator that can be easily managed even when the steam separator in the steam generator is configured using a plurality of tanks. The purpose is to do.

  The present invention provides a plurality of evaporation tanks arranged side by side in the horizontal direction and generating steam therein, and provided below the plurality of evaporation tanks, in which water that has not evaporated is stored inside the plurality of evaporation tanks. A tank section having a collecting tank, a tube extending in the horizontal direction inside the evaporating tank, in which hot water serving as a heat source flows, a hot water supply line supplying hot water to the tube, and the tube A hot water discharge line for discharging hot water from the inside of the evaporation tank; a spray nozzle for spraying water on the tube; and an upper portion of the evaporation tank. A steam deriving section for deriving steam generated inside; a spray water supply line for supplying water stored in the collecting tank to the spray nozzle; And the spray water feed pump provided in the spray water supply line, to a steam generator comprising a.

  A plurality of the spray nozzles are arranged in the center region in the width direction of the evaporation tank with a predetermined interval in the depth direction of the evaporation tank, and the tube extends in the depth direction of the evaporation tank, It is preferable that a plurality of tubes are arranged in the width direction, and the number of the tubes at the center portion in the width direction of the evaporation tank is larger than the number of the tubes at the side portions in the width direction of the evaporation tank.

  The steam generator according to the present invention further includes heat for exchanging heat between a makeup water line that supplies makeup water to the tank, makeup water that flows through the makeup water line, and warm water that flows through the warm water discharge line. And an exchanger.

  The steam generator of the present invention further includes a check valve provided in the makeup water line, and the check valve blocks the flow of water to the upstream side of the makeup water line and has a predetermined pressure. It is preferable to allow supply of makeup water to the tank section through the makeup water line when receiving the above water pressure.

  Moreover, it is preferable that the steam generator of this invention is further equipped with the bypass line which connects the said warm water supply line and the said warm water discharge line.

  According to the steam generator of the present invention, management can be easily performed even when the steam separator is configured using a plurality of tanks.

It is a figure which shows the outline of the steam generator which concerns on embodiment of this invention. It is a perspective view which shows the tank part (evaporation tank) in the steam generator which concerns on embodiment of this invention. It is sectional drawing of the tank part (evaporation tank) in the steam generator which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an outline of a steam generator according to an embodiment of the present invention.
The steam generator 1 of the present embodiment generates steam using a relatively low-temperature heat source such as exhaust heat of jacket cooling water of a gas engine. The steam generated in the steam generator 1 is compressed and sent to, for example, an exhaust heat recovery boiler.

  The steam generator 1 includes a tank part 2, a steam outlet part 24 provided in the tank part 2, a tube 25 and a spray nozzle 23 arranged in the tank part 2, a hot water supply line L1, and a hot water discharge line. L2, steam outlet line L3, spray water supply line L4, spray water supply pump 7 provided in spray water supply line L4, continuous blow line L5, concentration blow line L6, makeup water line L7, bypass The line L8 and the heat exchanger 3 are included. “Line” is a general term for lines capable of flowing fluid such as flow paths, paths, and pipelines.

The tank unit 2 includes a plurality of evaporation tanks 21 and one collective tank 22. Each of the plurality of evaporation tanks 21 generates steam.
The collective tank 22 is disposed below the plurality of evaporation tanks 21. The collecting tank 22 stores water that has not become steam inside the evaporation tank 21.
The vapor outlet 24 is provided on each of the plurality of evaporation tanks 21. The steam deriving unit 24 derives the steam generated in the evaporation tank 21.

The tube 25 extends in the horizontal direction inside the evaporation tank 21. Inside the tube 25, hot water serving as a heat source flows.
The spray nozzle 23 is disposed above the tube 25 inside the evaporation tank 21. The spray nozzle 23 sprays water toward the tube 25.
The tank unit 2, the vapor outlet unit 24, the spray nozzle 23, and the tube 25 will be described in detail later.

  The hot water supply line L <b> 1 supplies hot water serving as a heat source to the tube 25. The upstream side of the hot water supply line L1 is connected to a gas engine or the like that supplies hot water serving as a heat source. The downstream side of the hot water supply line L <b> 1 is connected to one end of the tube 25.

  The hot water discharge line L2 circulates inside the tube 25 and discharges the hot water used as a heat source to the outside. The upstream side of the hot water discharge line L <b> 2 is connected to the other end of the tube 25.

  The steam lead line L3 leads the steam generated inside the evaporation tank 21. The upstream side of the steam outlet line L3 is connected to the steam outlet 24. The downstream side of the steam outlet line L3 is connected to an ejector, a steam compressor, etc. (not shown).

The spray water supply line L4 connects the collect tank 22 and the spray nozzle 23, and supplies water stored in the collect tank 22 to the spray nozzle 23 as spray water. A spray water supply pump 7 is disposed in the spray water supply line L4.
The spray water supply pump 7 pumps the water stored in the collecting tank 22 to the spray nozzle 23.

  The continuous blow line L5 and the concentrated blow line L6 branch from the spray water supply line L4. Part of the water stored in the collecting tank 22 is drained by the continuous blow line L5 and the concentrated blow line L6. A valve 5 and a valve 6 are arranged in the continuous blow line L5 and the concentration blow line L6, respectively.

The makeup water line L7 connects the collective tank 22 and a storage tank or the like that stores water. The makeup water line L7 supplies makeup water to the collecting tank 22. A makeup water supply pump 8 and a check valve 9 are arranged in the makeup water line L7.
The makeup water supply pump 8 pressurizes water supplied from a storage tank or the like and supplies it to the inside of the collecting tank 22. The check valve 9 blocks the flow of water to the upstream side of the makeup water line L7 and allows supply of makeup water to the collecting tank 22 through the makeup water line L7 when a water pressure higher than a predetermined pressure is received. To do.

  The bypass line L8 branches from each of the hot water supply line L1 and the hot water discharge line L2, and connects them. A valve 4 that is a three-way valve is disposed at a branch point from the hot water supply line L1 to the bypass line L8. By switching the valve 4, the supplied hot water can be discharged via the bypass line L 8 and the hot water discharge line L 2 without flowing through the tube 25 inside the tank unit 2.

  The heat exchanger 3 performs heat exchange between the hot water flowing through the hot water discharge line L2 and the water flowing through the makeup water line L7.

Next, the structure of the tank part 2, the vapor | steam derivation | leading-out part 24, the tube 25, and the spray nozzle 23 is demonstrated, referring FIG.2 and FIG.3.
FIG. 2 is a perspective view showing the tank unit 2 of the present embodiment. FIG. 3A shows the front surface of the evaporation tank 21 by cutting the evaporation tank 21 of FIG. 2 at a surface perpendicular to the depth direction and passing through a portion where the evaporation tank 21 and the spray water supply line L4 are connected. It is sectional drawing (sectional drawing of one evaporation tank 21) observed from the direction (X direction). FIG. 3B shows a cross section of the evaporation tank 21 observed at a central portion in the width direction of the evaporation tank 21 along a plane perpendicular to the width direction of the evaporation tank 21 and observed from the side surface direction (Y direction) of the evaporation tank 21. FIG.

In the present embodiment, the tank unit 2 includes four evaporation tanks 21 and one collective tank 22.
As shown in FIGS. 2 and 3, the evaporating tank 21 has a length (height) H1 in the height direction HD and a length (width) W1 in the width direction WD from the length (depth) D1 in the depth direction LD. Is also formed in a short rectangular parallelepiped shape. The plurality of evaporation tanks 21 are connected in the width direction WD.
The collecting tank 22 is disposed below the central region of the evaporation tank 21 in the depth direction LD. In the present embodiment, the collecting tank 22 is formed in a cylindrical shape that extends across the width direction WD of the plurality of evaporation tanks 21.
The evaporating tank 21 and the collecting tank 22 are connected via a plurality of pipes 26. More specifically, the upper ends of the plurality of pipes 26 are respectively connected to the lower surfaces of the plurality of evaporation tanks 21. The lower ends of the plurality of pipes 26 are connected to the upper part of the peripheral surface of the collective tank 22.

  The vapor outlet 24 is provided in the central region in the width direction WD of the evaporation tank 21 and in the central region in the depth direction LD of the evaporation tank 21.

  The tubes 25 extend in the depth direction LD of the evaporation tank 21, are arranged in the width direction WD of the evaporation tank 21, and are further arranged in the height direction HD of the evaporation tank 21. Further, the interval W2 between the tubes 25 arranged at the center portion in the width direction WD of the evaporation tank 21 is narrower than the interval W3 between the tubes 25 arranged at the side portions in the width direction WD of the evaporation tank 21. That is, the number of tubes 25 arranged in the central portion of the evaporation tank 21 in the width direction WD is larger than the number of tubes 25 arranged in the side portions of the evaporation tank 21 in the width direction WD.

  The tube 25 present in the lower half of the evaporation tank 21 in the height direction HD is connected to the hot water supply line L1, and the tube 25 of the tube 25 present in the upper half of the evaporation tank 21 in the height direction HD is Connected to the hot water discharge line L2. The tube 25 existing in the lower half of the evaporating tank 21 in the height direction HD and the tube 25 existing in the upper half of the evaporating tank 21 in the height direction HD are connected to the inner side of the evaporating tank 21 in the depth direction LD. The hot water supplied from the supply line L1 circulates through the tube 25 existing in the lower half of the evaporating tank 21 in the height direction HD and then turns back to circulate through the tube 25 existing in the upper half of the evaporating tank 21 in the height direction HD. And is discharged by the hot water discharge line L2.

  A plurality of spray nozzles 23 are arranged in the center region in the width direction WD of the evaporation tank 21 with a predetermined interval in the depth direction LD of the evaporation tank 21. In the present embodiment, two spray nozzles 23 are arranged on the back side and the near side of the steam outlet 24. The spray angle of the spray nozzle 23 is wide and close to 180 °.

The steam generator 1 of this embodiment operates as follows.
First, hot water of about 91 ° C. serving as a heat source from a gas engine or the like is supplied to the tube 25 through the hot water supply line L1. The hot water supplied to the tube 25 flows through the tube 25 on the lower side in the height direction HD of the tank unit 2, and then flows through the tube 25 on the upper side in the height direction HD of the evaporation tank 21.
On the other hand, spray water is sprayed from the spray nozzle 23 toward the tube 25 inside the evaporation tank 21. Further, the inside of the evaporation tank 21 is maintained at a negative pressure (for example, -0.043 MPaG). As a result, the hot water flowing through the tube 25 is deprived of heat by the spray water, drops to about 84 ° C., and is discharged through the hot water discharge line L2.

  In addition, a thin liquid film is formed on the surface of the tube 25 through which warm water flows by spraying water at about 82 ° C. from the spray nozzle 23. Thus, in a state where the negative pressure is maintained, a thin liquid film is formed on the surface of the tube 25, so that the temperature difference between the hot water flowing through the tube 25 and the water sprayed by the spray nozzle 23 is increased. Even when it is relatively small (for example, about 9 ° C.), steam can be generated efficiently.

  Since water sprayed from the spray nozzle 23 evaporates on the surface of the tube 25, the liquid film on the surface of the tube 25 becomes thinner toward the tube 25 on the lower side in the height direction HD of the evaporation tank 21. As described above, if the hot water is circulated through the tube on the lower side in the height direction HD of the evaporation tank 21 and then the tube on the upper side in the height direction HD of the evaporation tank 21 is circulated, As the tube 25 circulates, the liquid film on the surface of the tube 25 becomes thinner. Since the steam generation efficiency of the entire steam generator tends to be higher when heat exchange between warm water and liquid film water is performed in a thin portion of the liquid film on the surface of the tube 25, the higher the evaporation tank 21. In the vertical direction HD, hot water serving as a heat source is circulated in the order of the upper tube 25 from the lower evaporation tank 21.

  The steam generated inside the evaporation tank 21 is led out from the steam lead-out unit 24 and supplied to an ejector, a steam compressor, and the like through the steam lead-out line L3.

  Water that has not become steam inside the evaporation tank 21 is stored in the collecting tank 22. The water stored in the collecting tank 22 is pumped up to the spray nozzle 23 by the spray water supply pump 7 through the spray water supply line L4 and sprayed on the tube 25 again.

  The continuous blow line L5 and the concentrated blow line L6 branched from the spray water supply line L4 drain the water stored in the collecting tank 22. Since the water stored in the collective tank 22 circulates between the spray water supply line L4 and the tank unit 2, if the circulation is continued, the water stored in the collective tank 22 will be stored in the evaporation tank 21. It decreases by the amount of vapor generated in, and the concentration of harmful ions such as chloride ions increases. In order to avoid an increase in the risk of corrosion and failure of the steam generator 1 due to overconcentration of the circulating water, the water circulating through the continuous blow line L5 and the concentrated blow line L6 is discharged. The continuous blow line L5 and the concentration blow line L6 are provided with a valve 5 and a valve 6, respectively. The continuous blow line L5 always discharges a fixed amount of water by opening the valve 5, or discharges a fixed amount of water every fixed time. The concentration blow line L6 monitors the concentration value of chloride ions etc. of the water stored in the tank unit 2, and when the value exceeds a certain standard, the valve 6 is opened and a certain amount of water is discharged. .

  When the amount of water circulating between the spray water supply line L4 and the tank unit 2 is reduced, make-up water is supplied to the collecting tank 22 from the make-up water line L7. The water replenished by the makeup water line L7 is about 20 ° C. The water replenished by the replenishing water line L7 exchanges heat with the hot water flowing through the warm water discharge line L2 by the heat exchanger 3. The water supplied by the makeup water line L7 is heated to, for example, about 40 ° C. by exchanging heat with the warm water flowing through the warm water discharge line L2.

  In addition, the water flow to the upstream side of the make-up water line L7 is interrupted, and the supply of make-up water to the collecting tank 22 by the make-up water line L7 when the water pressure exceeds a predetermined pressure is provided. By providing the check valve 9 in the make-up water line L7, it is possible to prevent the make-up water from flowing into the collecting tank 22 immediately after the steam generator 1 is stopped. That is, since the inside of the tank unit 2 (evaporation tank 21 and collective tank 22) is at a negative pressure during operation of the steam generator 1, the makeup water will flow into the tank immediately after the steam generator 1 is stopped. However, since the check valve 9 requires a certain amount of pressure for water to flow in the forward direction (collection tank 22 side), the inside of the tank unit 2 (evaporation tank 21 and collective tank 22) is slightly As long as the pressure is negative, the makeup water does not flow into the collecting tank 22 side.

  The steam generator 1 includes a bypass line L8. When some trouble occurs in peripheral equipment such as a steam compressor connected downstream of the steam outlet line L3, if hot water continues to flow through the tube 25 in the evaporation tank 21, the temperature in the evaporation tank 21 is Undesirable and excessive amounts of steam are generated. In the case of such trouble with peripheral devices, the hot water is not circulated through the tube 25 in the evaporation tank 21, but the hot water is circulated through the bypass line L8 by switching the valve 4, thereby generating an excessive amount of steam. Can be prevented. In addition, by using the bypass line L8 instead of stopping the power supply for the entire steam generator 1, the water level and temperature of the water stored in the collective tank 22 are not lowered, and the peripheral equipment is troubled. It is possible to speed up the start of steam generation even when the plant is restored.

  The steam generator 1 according to the present embodiment has the following effects.

(1) The tank unit 2 is configured to include a plurality of evaporation tanks 21 and one collecting tank 22, and water that has not evaporated in the plurality of evaporation tanks 21 is stored in the collecting tank 22. Accordingly, by monitoring the amount of water stored in one collective tank 22, the supply of water in the steam generator 1 can be controlled. Therefore, even when the steam generator 1 is constituted by a plurality of evaporation tanks 21, the steam generator 1 can be easily managed.
In addition, since the water that has not evaporated in the evaporation tank 21 is stored in the collective tank 22, the height of the evaporation tank 21 can be reduced. Therefore, by shortening the length of the evaporating tank 21 in the height direction, the evaporating tank 21 can be reduced in size, or the tube 25 can be arranged below the inside of the evaporating tank 21. .
Moreover, the evaporation tank 21 can be reduced in size by comprising the tank part 2 including the some evaporation tank 21. FIG. Therefore, the evaporation tank 21 can be manufactured with a thin film thickness, and the manufacturing cost of the evaporation tank 21 can be reduced. In addition, by making the plurality of evaporating tanks 21 fit within the small pressure vessel standard, management costs such as installation notification and performance inspection can be reduced.

  (2) A plurality of spray nozzles 23 are arranged in the central region of the evaporation tank 21 in the width direction WD with a predetermined interval in the depth direction LD of the evaporation tank 21, and the tube 25 is extended in the depth direction LD of the evaporation tank 21, A plurality of rows are arranged in the width direction WD of the evaporation tank 21, and the number of the tubes 25 in the central portion of the evaporation tank 21 in the width direction WD is larger than the number of the tubes 25 in the side portion of the evaporation tank 21 in the width direction WD. The configuration. Even if the spray angle of the spray nozzle 23 is wide, the central portion of the evaporation tank 21 in the width direction WD has more water to be sprayed than the side portion. By disposing more tubes 25 at the center of the WD than at the sides, a liquid film can be uniformly formed on the surface of the tubes 25, and the steam generation efficiency of the steam generator 1 is increased. It is possible.

  (3) By providing the heat exchanger 3 that performs heat exchange between the hot water flowing through the hot water discharge line L2 and the make-up water flowing through the make-up water line L7, the temperature of the make-up water supplied to the tank unit 2 is set. It can be raised in advance, and the steam generation efficiency of the steam generator 1 can be increased.

  (4) Since the inside of the tank unit 2 (the evaporation tank 21 and the collecting tank 22) is at a negative pressure during the operation of the steam generator 1, the makeup water is supplied to the tank unit 2 side immediately after the steam generator 1 is stopped. The force that tries to flow in works. Therefore, a check valve 9 that allows supply of makeup water to the collecting tank 22 when a water pressure equal to or higher than a predetermined pressure is applied to the makeup water line L7. As a result, since a predetermined pressure is required for the water to flow to the collecting tank 22 side, the makeup water is supplied even if the tank portion 2 (evaporation tank 21 and collecting tank 22) has a slightly negative pressure. Can be prevented from flowing into the collecting tank 22 side.

(5) When some trouble occurs in peripheral equipment such as a steam compressor connected downstream of the steam outlet line L3, if hot water continues to flow through the tube 25 in the evaporation tank 21, the inside of the evaporation tank 21 The temperature does not decrease, and an excessive amount of undesired steam is generated. Therefore, the steam generator 1 is configured including the bypass line L8. As a result, when trouble occurs in the peripheral device, etc., by circulating hot water through the bypass line L8, the flow of hot water to the tank unit 2 can be interrupted, so that an excessive amount of steam can be prevented from being generated.
Moreover, since warm water can be distribute | circulated to the bypass line L8 and the distribution | circulation of the warm water to the tank part 2 can be interrupted | blocked, generation | occurrence | production of a steam can be suppressed, without stopping the power supply of the steam generator 1 whole. Therefore, since the water level and water temperature inside the collective tank 22 caused by stopping the power supply do not occur, the start-up of steam generation can be accelerated even when the peripheral device is recovered from the trouble.

  The preferred embodiment of the steam generator of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and can be modified as appropriate.

DESCRIPTION OF SYMBOLS 1 Steam generator 2 Tank part 3 Heat exchanger 4, 5, 6 Valve 7 Spray water supply pump 8 Makeup water supply pump 9 Reverse support valve 21 Evaporation tank 22 Collecting tank 23 Spray nozzle 24 Steam outlet 25 Tube 26 Piping L1 Hot water supply Line L2 Hot water discharge line L3 Steam outlet line L4 Spray water supply line L5 Continuous blow line L6 Concentrated blow line L7 Makeup water line L8 Bypass line

Claims (5)

A plurality of evaporating tanks arranged side by side in the horizontal direction and generating steam therein; and a collecting tank provided below the plurality of evaporating tanks and storing water that has not evaporated in the evaporating tanks. A tank part having,
A tube that extends in the horizontal direction inside the evaporation tank and in which hot water that serves as a heat source circulates,
A hot water supply line for supplying hot water to the tube;
A hot water discharge line for discharging hot water from the tube;
A spray nozzle that is disposed above the tube inside the evaporation tank and sprays water on the tube;
A vapor outlet section provided at an upper portion of the evaporation tank, for deriving the vapor generated inside the evaporation tank;
A spray water supply line for supplying water stored in the collecting tank to the spray nozzle;
A steam generator comprising: a spray water supply pump provided in the spray water supply line. A plurality of the spray nozzles are arranged at predetermined intervals in the depth direction of the evaporation tank in the central region in the width direction of the evaporation tank,
The tubes extend in the depth direction of the evaporation tank, and are arranged in a plurality of rows in the width direction of the evaporation tank.
The steam generator according to claim 1, wherein the number of the tubes in the central portion in the width direction of the evaporation tank is larger than the number of the tubes in the side portions in the width direction of the evaporation tank. A makeup water line for supplying makeup water to the collective tank;
The steam generator according to claim 1, further comprising: a heat exchanger that performs heat exchange between makeup water flowing through the makeup water line and warm water flowing through the warm water discharge line. A check valve provided in the makeup water line;
The check valve blocks the flow of water to the upstream side of the make-up water line and allows supply of make-up water to the collecting tank by the make-up water line when a water pressure higher than a predetermined pressure is received. The steam generator according to claim 3.   The steam generator according to any one of claims 1 to 4, further comprising a bypass line connecting the hot water supply line and the hot water discharge line.

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