Waste heat boiler starting heating device and method

Abstract

The invention discloses a waste heat boiler starting heating device and method, and relates to the technical field of hot boiler starting heating. The method comprises the steps that water is injected into a kettle type heater to the normal water level, and the water level is higher than a first horizontal pipe; starting a heating pipeline in operation, and observing the temperature change on thermometers at the two ends of the shell of the kettle type heater; the blow-down valve is slowly opened, boiler water is continuously discharged, and the water level is kept constant according to the steam inlet amount and the blow-down amount. And boiler water is heated to 160 DEG C before the unit is ignited by continuously feeding steam and discharging water. Through continuous steam admission and drainage, boiler water is heated to a proper temperature before a unit is ignited, the water is continuously heated to an operation temperature through short-time replacement, the high boiler water temperature does not cause precipitation of corrosive salts caused by too low synthetic gas temperature, a waste heat boiler is prevented from being corroded by crystals in a pipeline, and the service cycle is greatly prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of waste heat boiler startup heating, and in particular to a waste heat boiler startup heating device and method. Background Art

[0002] The synthesis gas at the outlet of the gasifier contains high thermal energy. In order to further reduce the synthesis gas temperature and improve the unit efficiency, a waste heat boiler is installed downstream to reduce the temperature from 335℃ to 210℃.

[0003] Since the synthesis gas contains a large amount of corrosive gases, after heat exchange and cooling, corrosive salts and condensate will precipitate, which can easily cause corrosion of the heat exchange tubes. In the initial stage of startup, the water temperature in the waste boiler is low, which can easily cause cold liquid precipitation. Due to the compact structure of the waste boiler kettle heater, it is difficult to heat the water to a suitable temperature in the initial stage.

[0004] There is an urgent need to provide a waste heat boiler startup heating device and method. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] In view of the above problems existing in the existing waste heat boiler startup heating device, the present invention is proposed.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a waste heat boiler startup heating device, including a kettle heater and a thermometer arranged on the kettle heater, including a heating pipe, a water injection pipe, and a drain valve arranged on the kettle heater; the heating pipe and the water injection pipe are both installed inside the kettle heater, and the heating pipe is used to quickly heat the water in the boiler to the operating temperature.

[0008] As a preferred solution of the waste heat boiler startup heating device of the present invention, the heating pipeline includes a steam inlet arranged at the top of the kettle heater, two branch pipes 1 extending downward to below the liquid level in the middle of the heater in two ways, and a horizontal pipe 1 connected to the two branch pipes 1 respectively;

[0009] The water injection pipeline includes a water inlet arranged at the top of the kettle heater, two branch pipes 2 extending downward to below the liquid level in the middle of the heater in two ways, and a horizontal pipe 2 connected to the two branch pipes respectively;

[0010] The height of the horizontal tube 1 is greater than the height of the horizontal tube 2, and the horizontal tube 1 is located below the middle liquid level in the kettle heater.

[0011] As a preferred solution of the waste heat boiler startup heating device of the present invention, the lengths of the horizontal tube 1 and the horizontal tube 2 are both close to the total length inside the heat exchanger.

[0012] As a preferred embodiment of the waste heat boiler startup heating device of the present invention, a 6-8 mm hole is opened on the upper part of the horizontal tube. When the heating tube is started, the water in the tube is squeezed out due to the high steam pressure, and the exhaust gas is heated from the inside of the tube to the upper part.

[0013] As a preferred solution of the waste heat boiler startup heating device of the present invention, the drain valve is used to continuously discharge boiler water during the startup heating process.

[0014] The beneficial effects of the present invention are as follows: the temperature of the kettle heater can be raised to a suitable temperature quickly and safely through the device, a higher temperature environment is provided for the synthesis gas, and the precipitation of corrosive salts is effectively prevented.

[0015] In view of the problems existing in the above-mentioned existing waste heat boiler startup heating method, the present invention is proposed.

[0016] In order to solve the above technical problems, the present invention provides the following technical solutions: a waste heat boiler startup heating method, applied to the waste heat boiler startup heating device as described above, comprising:

[0017] S1: Fill the kettle heater with water to the normal water level, and the water level will overflow the horizontal pipe 1;

[0018] S2: Start the heating pipeline and observe the temperature changes on the thermometers at both ends of the shell of the kettle heater;

[0019] S3: Slowly open the drain valve to continuously drain the boiler water. According to the amount of steam inlet and the amount of drain, keep the water level constant.

[0020] S4: By continuously supplying steam and draining water, the boiler water is heated to 160℃ before the unit is ignited.

[0021] As a preferred embodiment of the waste heat boiler startup heating method of the present invention, before the whole unit is started, a water pressure test is performed on the kettle heater to ensure the sealing and structural integrity of the waste heat boiler;

[0022] Check and confirm that all safety valves, pressure gauges and thermometers are in normal working condition, and confirm that the valve transmission test is normal;

[0023] Ensure that the pipes connecting the waste heat boiler to the steam-water system are intact.

[0024] As a preferred embodiment of the waste heat boiler startup heating method of the present invention, the water source for injection is desalted water.

[0025] As a preferred solution of the waste heat boiler startup heating method of the present invention, during the heating process, the pressure and temperature of the waste heat boiler are regularly checked to ensure that they are within a safe operating range.

[0026] As a preferred embodiment of the waste heat boiler startup heating method of the present invention, after the unit is started, due to the heating of the synthesis gas, the boiler water quickly reaches the saturation temperature of the corresponding pressure, and the synthesis gas is cooled to above 210°C, which is higher than the crystallization temperature of the ammonium salt.

[0027] The beneficial effects of the present invention are as follows: by continuously inletting steam and draining water, the boiler water is heated to about 160°C before the unit is ignited. After a short period of replacement, the water is continuously heated to the operating temperature. The higher boiler water temperature will not cause the synthesis temperature to be too low to cause the precipitation of corrosive salts, thus avoiding crystallization inside the pipeline to corrode the waste heat boiler, and greatly enhancing the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0029] Figure 1 It is a side structural schematic diagram of the present invention.

[0030] Figure 2 It is a schematic diagram of the front and side structures of the present invention.

[0031] Figure 3 It is a schematic diagram of the back structure of the present invention. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0034] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0035] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0036] Example 1

[0037] Reference Figure 1 to Figure 3 , which is the first embodiment of the present invention, provides a waste heat boiler startup heating device, including a kettle heater 100 and thermometers 200 arranged at both ends of the shell of the kettle heater 100. The kettle heater 100 is the core part of the device, designed to accommodate water and provide sufficient surface area to achieve effective heat exchange. The thermometer 200 is installed at both ends of the shell of the kettle heater 100 to monitor the water temperature inside the kettle heater 100.

[0038] The device also includes a heating pipe 300, a water injection pipe 400, and a drain valve 500 arranged on the kettle heater 100. The heating pipe 300 and the water injection pipe 400 are both installed inside the kettle heater 100. The main part of the heating pipe 300 is located below the liquid level in the middle of the heater, and the drain valve 500 is located in the middle of the kettle heater 100.

[0039] At the beginning of startup, the water injection pipe 400 is used to inject an initial amount of water into the boiler to ensure that the kettle heater 100 has enough water to absorb heat and perform heat exchange before startup. During the startup heating process, the water injection pipe 400 is used to inject water with a lower temperature to reduce the temperature in the boiler and prevent equipment damage or safety accidents caused by excessive temperature; the heating pipe 300 is used to quickly heat the water in the boiler to the operating temperature, and the drain valve 500 is used to discharge the water inside the boiler to assist heat exchange.

[0040] Example 2

[0041] Reference Figure 1 to Figure 3 , which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that: the heating pipeline 300 includes a steam inlet 301 arranged at the top of the kettle heater 100, two branch pipes 302 extending in two ways to below the liquid level in the middle of the heater, and a horizontal pipe 303 connected to the two branch pipes 302 respectively. The steam enters the two horizontal pipes through the two branch pipes 302. The steam is divided into two ways after entering from the inlet, which disperses the steam introduction points, thereby reducing the risk of local overheating, and can also increase the surface area of ​​heat exchange, so that more water can be heated at the same time, thereby accelerating the heating process.

[0042] The water injection pipeline 400 includes a water inlet 401 arranged at the top of the kettle heater 100, two branch pipes 402 extending downward in two ways to below the liquid level in the middle of the heater, and a horizontal pipe 403 connected to the two branch pipes respectively; the height of the horizontal pipe 1 303 is greater than the height of the horizontal pipe 2 403, and the horizontal pipes 1 303 are all located below the liquid level in the middle of the kettle heater 100. Arranging the horizontal pipe 1 303 below the liquid level can ensure that the contact area between steam and water is maximized, thereby improving the heat exchange efficiency. The water temperature below the liquid level is relatively low, and the contact between steam and low-temperature water can transfer heat more effectively. If the steam is released directly on the liquid surface, it may cause rapid heating of the local area, thereby generating thermal stress. Arranging the horizontal pipe below the liquid level can reduce this thermal stress and protect the internal structure of the boiler.

[0043] Mounting frames are provided on the lower sides of horizontal tube 1 303 and horizontal tube 2 403 to provide support for horizontal tube 1 303 and horizontal tube 2 403. The lengths of horizontal tube 1 303 and horizontal tube 2 403 are close to the total length of the heat exchanger, which is also to increase the range of heat exchange, improve the efficiency of heat exchange, and make the heat exchange inside the entire kettle heater 100 evenly distributed.

[0044] A 6-8mm hole is opened on the upper part of the horizontal pipe 303. When the heating pipe is started, the steam pressure is high, which squeezes out the water in the pipe and exhausts the gas from the inside of the pipe to the upper part. The heating drain valve 500 is used to continuously discharge the boiler water during the startup heating process.

[0045] The remaining structures are the same as those of Example 1.

[0046] Example 3

[0047] The third embodiment of the present invention is different from the second embodiment in that: a waste heat boiler startup heating method is applied to the waste heat boiler startup heating device mentioned above, comprising:

[0048] S1: Fill the kettle heater 100 with water to a normal water level, the water level basically overflowing the horizontal pipe 1 303;

[0049] S2: Start the heating pipeline 300 and observe the temperature change on the thermometers 200 at both ends of the shell of the kettle heater 100;

[0050] S3: Slowly open the drain valve 500 to continuously drain the boiler water. According to the amount of steam inlet and the amount of drain, keep the water level constant.

[0051] S4: By continuously supplying steam and draining water, the boiler water is heated to about 160℃ before the unit is ignited.

[0052] Before starting the whole unit, conduct a water pressure test on the kettle heater 100 to ensure the sealing and structural integrity of the waste heat boiler; check and confirm that all safety valves, pressure gauges and thermometers 200 are in normal working condition, and confirm that the valve transmission test is normal; ensure that the waste heat boiler is connected to the steam-water system pipeline in good condition.

[0053] During the heating process, the pressure and temperature of the waste heat boiler are checked regularly to ensure that they are within the safe operating range.

[0054] The water source for injection is desalted water, which has a low content of dissolved solids, which can reduce the formation of scale. The desalted water also contains fewer minerals and salts, which may cause corrosion to boiler metal at high temperatures. Using desalted water can reduce this corrosion risk.

[0055] After the unit is started, due to the heating of the synthesis gas, the boiler water quickly reaches the saturation temperature of the corresponding pressure, and the synthesis gas is cooled to above 210°C, which is higher than the crystallization temperature of ammonium salt, avoiding crystallization corrosion inside the pipeline.

[0056] In summary, after a short period of replacement, the water is continuously heated to the operating temperature. The higher boiler water temperature will not cause the synthesis temperature to be too low to cause the precipitation of corrosive salts, and the service life of the waste heat boiler is greatly enhanced.

[0057] The remaining structure is the same as that of Example 2.

[0058] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0059] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0060] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0061] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A waste heat boiler startup heating device, comprising a kettle heater (100) and a thermometer (200) arranged on the kettle heater (100), characterized in that: The invention comprises a heating pipe (300), a water injection pipe (400), and a drain valve (500) arranged on a kettle heater (100); the heating pipe (300) and the water injection pipe (400) are both installed inside the kettle heater (100); the heating pipe (300) is used to quickly heat the water in the boiler to the operating temperature.

2. The waste heat boiler startup heating device according to claim 1, characterized in that: The heating pipeline (300) comprises a steam inlet (301) arranged at the top of the kettle heater (100), two branch pipes (302) extending downward to below the liquid level in the middle of the heater in two ways, and a horizontal pipe (303) connected to the two branch pipes (302) respectively; The water injection pipeline (400) comprises a water inlet (401) arranged at the top of the kettle heater (100), two branch pipes (402) extending downward to below the liquid level in the middle of the heater in two ways, and a horizontal pipe (403) connected to the two branch pipes respectively; The height of the horizontal tube 1 (303) is greater than the height of the horizontal tube 2 (403), and the horizontal tube 1 (303) is located below the middle liquid level in the kettle heater (100).

3. The waste heat boiler startup heating device according to claim 2 is characterized in that: The lengths of the horizontal tube 1 (303) and the horizontal tube 2 (403) are both close to the total length inside the heat exchanger.

4. The waste heat boiler startup heating device according to claim 3 is characterized in that: A hole of 6-8 mm is opened on the upper part of the horizontal pipe 1 (303). When the heating pipe is started, the water in the pipe is squeezed out due to the high steam pressure, and the exhaust gas is heated from the inside of the pipe to the upper part.

5. The waste heat boiler startup heating device according to claim 4 is characterized in that: The drain valve (500) is used to continuously drain boiler water during the start-up heating process.

6. A method for starting and heating a waste heat boiler, applied to the waste heat boiler starting and heating device as claimed in any one of claims 2 to 5, characterized in that: include: S1: Fill the kettle heater (100) with water to a normal water level, the water level overflowing the horizontal pipe 1 (303); S2: putting the heating pipeline (300) into operation and starting up, and observing the temperature changes on the thermometers (200) at both ends of the shell of the kettle heater (100); S3: Slowly open the drain valve (500) to continuously drain the boiler water. According to the amount of steam inlet and the amount of drain, keep the water level constant. S4: By continuously supplying steam and draining water, the boiler water is heated to 160℃ before the unit is ignited.

7. The waste heat boiler startup heating method according to claim 6, characterized in that: Before the whole unit is started, the kettle heater (100) is subjected to a water pressure test to ensure the sealing and structural integrity of the waste heat boiler; Check and confirm that all safety valves, pressure gauges and thermometers (200) are in normal working condition, and confirm that the valve transmission test is normal; Ensure that the pipes connecting the waste heat boiler to the steam-water system are intact.

8. The waste heat boiler startup heating method according to claim 7, characterized in that: The water source for injection is desalted water.

9. The waste heat boiler startup heating method according to claim 8, characterized in that: During the heating process, the pressure and temperature of the waste heat boiler are checked regularly to ensure that they are within the safe operating range.

10. The waste heat boiler startup heating method according to claim 9, characterized in that: After the unit is started, due to the heating of the synthesis gas, the boiler water quickly reaches the saturation temperature of the corresponding pressure, and the synthesis gas is cooled to above 210°C, which is higher than the crystallization temperature of ammonium salt, avoiding crystallization corrosion inside the pipeline.

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