阅读说明：本技术 一种下降管、下降管组及吸热系统 (Downcomer, downcomer group and heat absorption system ) 是由 徐能 周慧 王建熊 唐亚平 陈明强 于 2020-12-16 设计创作，主要内容包括：本发明公开了一种下降管、下降管组及吸热系统,包括输入段、连接段、输出段、下降管调阀。输入段的首端连通于外部吸热器,尾端连通于下降管调阀的首端。连接段的首端连通于下降管调阀的尾端,尾端连通于输出段的首端。输出段的尾端连通于外部储罐的入口。输出段最高点的高度高于连接段的最低点高度。将输出段的最高点设为高于连接段的最低点,从而实现一类似于“U”型管道的效果,吸热介质在流经下降管调阀后,充满从连接段至输出段最高点的管道,排出该部分的气体以避免该段因气液两相流产生振动,而将气液两相流振动发生的位置推迟至外部储罐的入口处,从而有效避免下降管调阀处的振动,避免了对下降管及下降管调阀运行造成损害。(The invention discloses a downcomer, a downcomer group and a heat absorption system. The head end of the input section is communicated with an external heat absorber, and the tail end of the input section is communicated with the head end of the down pipe regulating valve. The head end of the connecting section is communicated with the tail end of the down pipe regulating valve, and the tail end of the connecting section is communicated with the head end of the output section. The tail end of the output section is communicated with the inlet of the external storage tank. The height of the highest point of the output section is higher than that of the lowest point of the connecting section. The highest point of the output section is set to be higher than the lowest point of the connecting section, so that an effect similar to a U-shaped pipeline is achieved, the heat absorbing medium is filled in the pipeline from the connecting section to the highest point of the output section after flowing through the down pipe regulating valve, the part of gas is discharged to prevent the section from vibrating due to gas-liquid two-phase flow, and the position where the gas-liquid two-phase flow vibrates is delayed to the inlet of an external storage tank, so that the vibration of the down pipe regulating valve is effectively avoided, and the damage to the operation of the down pipe and the down pipe regulating valve is avoided.)

1. A downcomer is characterized by being installed in a heat absorption system and comprising an input section, a connecting section, an output section and a downcomer regulating valve;

the head end of the input section is communicated with an external heat absorber, and the tail end of the input section is communicated with the head end of the down pipe regulating valve;

the head end of the connecting section is communicated with the tail end of the down pipe regulating valve, and the tail end of the connecting section is communicated with the head end of the output section;

the tail end of the output section is communicated with an inlet of the external storage tank;

the height of the highest point of the output section is higher than that of the lowest point of the connecting section.

2. A downcomer according to claim 1, wherein said connecting section is a horizontal pipe and the height of said downcomer damper is lower than the height of the inlet of said external storage tank.

3. A downcomer according to claim 1, wherein said connecting section is a horizontal pipe, and the height of said downcomer damper is equal to or greater than the height of the inlet of said external storage tank; the output section comprises an upward-turning pipe, a middle pipe and a downward-turning pipe which are sequentially connected end to end, the head end of the upward-turning pipe is communicated with the tail end of the horizontal pipe, and the tail end of the downward-turning pipe is connected with an inlet of the external storage tank.

4. A downcomer according to claim 3, wherein said level is lower than the height of said downcomer damper.

5. The downcomer of claim 1, wherein the lowest point of said connecting section is connected to a salt phobic pipe, the tail end of said salt phobic pipe is connected to a salt phobic tank, and said salt phobic pipe is provided with a salt phobic valve.

6. A downcomer stack comprising two downcomers as claimed in any one of claims 1 to 5, the input ends of both downcomers being in communication with the output end of an external heat sink, the output ends being in communication with a hot salt storage tank and a cold salt storage tank, respectively.

7. The downcomer group according to claim 6, further comprising a communicating pipe, wherein both ends of the communicating pipe are respectively communicated to the connecting sections of the two downcomers, and the output sections of the two downcomers are provided with switch valves.

8. A heat absorption system comprising a downcomer according to any one of claims 1 to 5 or a downcomer stack according to any one of claims 6 to 7.

Technical Field

The invention belongs to the technical field of solar thermal power generation, and particularly relates to a downcomer, a downcomer group and a heat absorption system.

Background

In the tower type solar thermal power generation industry, whether a down pipe and a down pipe regulating valve of a heat absorption system can work safely and smoothly is directly related to the safe and stable operation of a power station. In current engineering practice, the vertical drop of the downcomer pipe is large and the pipeline is long due to the high height of the heat absorption tower. Meanwhile, the heat absorbing medium in the heat absorber naturally falls and flows into the storage tank in the descending pipe through self gravity, so that the flow rate of the heat absorbing medium in the pipe is very high, the heat absorbing medium flowing at high speed is rapidly mixed with the original retained air in the pipe to form intermittent gas-liquid two-phase flow, the vibration of the pipeline and the descending pipe at the position of the regulating valve is further aggravated, and the serious impact is caused on the whole descending pipe and the descending pipe regulating valve. The descending pipe has the characteristics of long pipeline length, large installation fall, great pressure drop before and after the descending pipe valve adjusting valve, and the like, so that the corresponding maintenance and replacement cost is high, the period is long, and the system safety and the stability of the heat absorption system are low.

Disclosure of Invention

The invention aims to provide a downcomer, a downcomer group and a heat absorption system.

In order to solve the problems, the technical scheme of the invention is as follows:

the invention discloses a downcomer which is arranged in a heat absorption system and comprises an input section, a connecting section, an output section and a downcomer regulating valve;

the head end of the input section is communicated with an external heat absorber, and the tail end of the input section is communicated with the head end of the down pipe regulating valve;

the head end of the connecting section is communicated with the tail end of the down pipe regulating valve, and the tail end of the connecting section is communicated with the head end of the output section;

the tail end of the output section is communicated with an inlet of the external storage tank;

the height of the highest point of the output section is higher than that of the lowest point of the connecting section.

According to the downcomer, the connecting section is a horizontal pipe, and the height of the downcomer adjusting valve is lower than that of the inlet of the external storage tank.

According to the downcomer, the connecting section is a horizontal pipe, and the height of the downcomer adjusting valve is higher than or equal to the height of an inlet of the external storage tank; the output section comprises an upward-turning pipe, a middle pipe and a downward-turning pipe which are sequentially connected end to end, the head end of the upward-turning pipe is communicated with the tail end of the horizontal pipe, and the tail end of the downward-turning pipe is connected with an inlet of the external storage tank.

According to the downcomer, the height of the horizontal pipe is lower than that of the downcomer adjusting valve.

According to the downcomer, the lowest point of the connecting section is communicated with the salt dredging pipe, the tail end of the salt dredging pipe is communicated with the salt dredging tank, and the salt dredging pipe is provided with the salt dredging valve.

The descending pipe group comprises two descending pipes, wherein the input ends of the two descending pipes are communicated with the output end of an external heat absorber, and the output ends of the two descending pipes are respectively communicated with a hot salt storage tank and a cold salt storage tank.

The descending tube group also comprises a communicating tube, two ends of the communicating tube are respectively communicated to the connecting sections of the two descending tubes, and the output sections of the two descending tubes are respectively provided with a switch valve.

A heat absorption system according to the present invention includes the downcomer described above or the downcomer group described above.

Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages and positive effects:

according to one embodiment of the invention, the downcomer is provided with the input section, the connecting section and the output section which are sequentially connected end to end, and the downcomer adjusting valve is arranged between the input section and the connecting section to adjust the flow of the heat absorbing medium in the downcomer. The highest point of the output section is set to be higher than the lowest point of the connecting section, so that an effect similar to a U-shaped pipeline is achieved, the heat absorbing medium is filled in the pipeline from the connecting section to the highest point of the output section after flowing through the down pipe regulating valve, the part of gas is discharged to avoid the section from generating vibration due to gas-liquid two-phase flow, the position where the gas-liquid two-phase flow vibration occurs is delayed to the inlet of an external storage tank, and damage to the operation of the down pipe and the down pipe regulating valve is avoided.

Drawings

FIG. 1 is a schematic view of a downcomer according to the present invention;

fig. 2 is another schematic view of a downcomer according to the present invention.

Description of reference numerals: 1: an input section; 2: a connecting section; 3: an output section; 301: turning up the tube; 302: an intermediate pipe; 303: downward turning the tube; 4: a down pipe regulating valve; 5: an external storage tank; 6: an inlet; 7: a salt dredging pipe; 8: a salt dredging valve; 9: and (4) switching on and off the valve.

Detailed Description

The present invention provides a downcomer, a downcomer stack and a heat absorption system, which are described in further detail below with reference to the accompanying drawings and specific embodiments. Advantages and features of the present invention will become apparent from the following description and from the claims.

Example one

Referring to fig. 1, in one embodiment, a downcomer is installed in a heat absorption system and comprises an input section 1, a connecting section 2, an output section 3, and a downcomer regulating valve 4.

Wherein, the head end of the input section 1 is communicated with the external heat absorber, and the tail end is communicated with the head end of the down pipe regulating valve 4. The head end of the connecting section 2 is communicated with the tail end of the down pipe regulating valve 4, and the tail end is communicated with the head end of the output section 3. The tail end of the output section 3 is communicated with an inlet 6 of an external storage tank 5. The highest point of the output section 3 is higher than the lowest point of the connecting section 2.

In the embodiment, the downcomer is provided with the input section 1, the connecting section 2 and the output section 3 which are sequentially connected end to end, and the downcomer adjusting valve 4 is arranged between the input section 1 and the connecting section 2 to adjust the flow of the heat absorbing medium in the downcomer. The highest point of the output section 3 is set to be higher than the lowest point of the connecting section 2, so that an effect similar to a U-shaped pipeline is achieved, the heat absorbing medium is filled in the pipeline from the connecting section 2 to the highest point of the output section 3 after flowing through the down pipe regulating valve 4, the part of gas is discharged to prevent the section from vibrating due to gas-liquid two-phase flow, and the position where the gas-liquid two-phase flow vibrates is delayed to the inlet 6 of the external storage tank 5, so that the vibration of the down pipe regulating valve 4 is effectively avoided, and the damage to the operation of the down pipe and the down pipe regulating valve 4 is avoided.

The following further describes the specific structure of the present embodiment:

in the embodiment, the output section 3 is higher than the connecting section 2, when the connecting section 2 is a horizontal pipe, that is, the connecting section 2 is a pipeline laid horizontally (in practical cases, it may have a certain slope downward along the output direction, and this is not limited specifically), there are the following situations:

firstly, referring to fig. 1, the height of the downcomer regulating valve 4 is lower than the height of the inlet 6 of the external tank 5. When the height of the descending regulating valve 4 is lower than the inlet 6 of the external storage tank 5, most of the connecting section 2 and the output section 3 are lower than the inlet 6, and only the tail end of the output section 3 is lifted for communicating with the inlet 6, so that the heat absorbing medium can fill the connecting section 2 and the output section 3 during transportation.

Secondly, referring to fig. 2, when the height of the descending pipe regulating valve 4 is higher than or equal to the height of the inlet 6 of the external storage tank 5, the output section 3 can be set to be in a shape like a Chinese character ji, that is, the output section 3 comprises an upturning pipe 301, a middle pipe 302 and a downturning pipe 303 which are sequentially connected end to end, the head end of the upturning pipe 301 is communicated with the tail end of the horizontal pipe, and the tail end of the downturning pipe 303 is connected with the inlet 6 of the external storage tank 5. The height of the horizontal pipe 302 relative to the connecting section 2 is raised through the upturned pipe 301, so that the heat absorbing medium can fill the connecting section 2 and the upturned pipe 301 during transportation, and the vibration generated by the gas-liquid two-phase flow can be delayed to the inlet 6 of the external storage tank 5.

Further, the height of the horizontal pipe 302 in the output section 3 may be set lower than the height of the down pipe damper 4. So that the elevation of the level pipe 302 does not generate excessive pressure at the drop tube damper 4 while ensuring that the heat absorbing medium can quickly fill the connecting section 2 and the upturned pipe 301.

In this embodiment, the lowest point of the connecting section 2 may be communicated with a salt dredging pipe 7, the tail end of the salt dredging pipe 7 is communicated with the salt dredging tank, and the salt dredging pipe 7 is provided with a salt dredging valve 8. In order to shut off the flow of heat absorbing medium in the downcomer to the external salt tank when required and to discharge the heat absorbing medium in the connecting section 2 type pipe through the desalination valve 8 to the desalination tank in case of emergency or long-term system non-operation.

In the present embodiment, the heat absorbing medium may be molten salt, water, liquid metal, or solid heat absorbing particles, and is not particularly limited herein.

Example two

The present embodiment is a further improvement of the first embodiment described above based on the situation that the outlet of the heat absorber is communicated with the cold salt storage tank and the hot salt storage tank at the same time.

Referring to fig. 1 and 2, it should be noted that the schematic diagram omits the illustration of the C-type buffer elbow of the horizontal pipe behind the downcomer regulating valve 4, and considering that the flows of the chilled salt storage tank and the heated salt storage tank behind the downcomer regulating valve 4 are symmetrically distributed along the normal line of the diagram, the schematic diagram also omits part of the flow of the chilled salt storage tank, only illustrates the flow of the chilled salt storage tank below the downcomer, and the storage tank is drawn to illustrate the chilled salt storage tank, i.e. the sides of the heated salt storage tank and the heated salt storage tank are also the same. The hot heat absorbing medium flows through the downcomer regulating valve 4 (generally designed to be used and spare) from the downcomer, flows to the cold salt tank at a lower temperature, and flows to the hot salt tank after the temperature is continuously raised to a set high temperature, and the flow direction of the hot salt tank can be controlled by a downcomer cold salt tank switching valve 9 and a downcomer hot salt tank switching valve 9 (not shown).

The descending pipe group of the embodiment comprises two descending pipes in the first embodiment, input ends of the two descending pipes are communicated with output ends of external heat absorbers, and output ends of the two descending pipes are communicated to a hot salt storage tank and a cold salt storage tank respectively. Further, the device comprises a communicating pipe, two ends of the communicating pipe are respectively communicated to the connecting sections 2 of the two descending pipes, and the output sections 3 of the two descending pipes are respectively provided with a switch valve 9. The heat absorbing medium can be controlled to be delivered to a required hot salt storage tank or cold salt storage tank by opening and closing two on-off valves 9.

EXAMPLE III

A heat absorption system of the present invention includes the downcomer of the first embodiment or the downcomer group of the second embodiment. The position of the occurrence of the vibration of the gas-liquid two-phase flow can be delayed to the inlet 6 of the external storage tank 5 by arranging the downcomer or the downcomer group, so that the vibration of the position of the adjustment valve 4 of the downcomer is effectively avoided, and the damage to the operation of the downcomer and the adjustment valve 4 of the downcomer is avoided. The descending pipe has the characteristics of longer pipeline length, larger installation fall, great pressure drop before and after the descending pipe adjusting valve 4, and the like, so that the corresponding maintenance and replacement cost is higher and long in period, and the system safety and stability of the tower type solar thermal power station are obviously improved and the operation and maintenance cost is reduced by adopting a mode of reducing the vibration of the descending pipe.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, it is still within the scope of the present invention if they fall within the scope of the claims of the present invention and their equivalents.