A low temperature corrosion control device for the tail heating surface of a waste heat incineration boiler

Abstract

The present invention relates to a low-temperature corrosion control device for the rear heating surface of a waste incineration waste heat boiler, and belongs to the technical field of boilers. The device solves the problem of serious low-temperature corrosion of the rear heating surface of the boiler. The device comprises a main water supply circuit, a water supply heating circuit and a regulating circuit, and the main water supply circuit is respectively connected with the water supply heating circuit and the regulating circuit. The present invention can adapt to various load conditions during the operation of the boiler, and realize that the exhaust gas temperature of the boiler is fully controllable. It can effectively control the low-temperature corrosion of the rear heating surface of the boiler, extend the service life of the heating surface of the boiler, and effectively reduce the heat loss of the exhaust gas, thereby improving the efficiency of the boiler.

Description

Technical Field

[0001] The invention relates to a low-temperature corrosion control device for a tail heating surface of a waste heat boiler, belonging to the technical field of boilers. Background Art

[0002] The sulfur in the garbage fuel combines with water vapor in the low smoke temperature zone to generate H2SO4 steam, which corrodes the heating surface of the low smoke temperature zone at the tail of the waste heat boiler, such as the economizer, air preheater, etc. The existing technology measures to control low-temperature corrosion are mainly to control the boiler exhaust temperature. Usually, during the boiler design process, the exhaust temperature is controlled at a fixed theoretical temperature by setting the economizer heat exchange area, and it does not have the ability to adjust. However, in the actual operation process, the waste incineration waste heat boiler has the characteristics of complex fuel type changes, large fluctuations in fuel calorific value and boiler load, and large fluctuations in flue gas volume and primary air volume. The above fluctuations will cause large fluctuations in the flue gas temperature at the tail of the boiler. When the flue gas temperature at the tail of the boiler is too high, it will affect the tail flue gas treatment efficiency and cause the boiler pollutant emissions to exceed the standard; at the same time, when the flue gas temperature at the tail of the boiler is too low, it will cause low-temperature corrosion of the heating surface at the tail of the boiler.

[0003] Therefore, it is urgent to propose a low-temperature corrosion control device for the rear heating surface of a waste incineration waste heat boiler to solve the above technical problems. Summary of the invention

[0004] The present invention is developed to solve the problem of severe low temperature corrosion of the heating surface at the rear of the boiler. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0005] The technical solution of the present invention:

[0006] A low-temperature corrosion control device for the tail heating surface of a waste incineration waste heat boiler comprises a main water supply circuit, a water supply heating circuit and a regulating circuit. The main water supply circuit is respectively connected with the water supply heating circuit and the regulating circuit.

[0007] Preferably: the main water supply circuit includes an air preheater, an economizer, a main regulating valve and a boiler drum, and the main regulating valve, the air preheater, the economizer and the boiler drum are connected in sequence to form the main water supply circuit.

[0008] Preferably: it also includes a first regulating valve, and the air preheater is arranged in parallel with the first regulating valve.

[0009] Preferably: the main regulating valve is a three-way regulating valve, and the main regulating valve has a valve main inlet, a first valve outlet and a second valve outlet;

[0010] The boiler drum has a boiler main inlet, a heating water pipeline outlet and a heating water pipeline inlet.

[0011] Preferably: the valve main inlet, the second valve outlet, the main pipeline, the air preheater arranged in parallel, the first regulating valve, the economizer, and the boiler main inlet are connected in sequence to form a main water supply path;

[0012] The valve main inlet, the first valve outlet, the heating water pipeline inlet, the heating water pipeline outlet, and the main pipeline are connected in sequence to form a water supply heating circuit;

[0013] The main line pipe, the second regulating valve and the main inlet of the boiler are connected in sequence to form a regulating line.

[0014] Preferably, the connection between the heating water pipeline outlet and the main pipe is located in front of the connection between the second regulating valve and the main pipe.

[0015] The present invention has the following beneficial effects:

[0016] The present invention can adapt to various load conditions during boiler operation and realize fully controllable boiler exhaust temperature. It can effectively control low-temperature corrosion of the boiler tail heating surface and extend the service life of the boiler heating surface, and can effectively reduce exhaust heat loss and improve boiler efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of a low-temperature corrosion control device for the tail heating surface of a waste incineration waste heat boiler of the present invention;

[0018] In the figure, 1-air preheater, 2-economizer, 3-second regulating valve, 4-first regulating valve, 5-main regulating valve, 6-boiler drum, 7-main pipe, 51-valve main inlet, 52-first valve outlet, 53-second valve outlet, 61-boiler main inlet, 62-heating water pipeline outlet, 63-heating water pipeline inlet. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0020] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] Specific implementation method 1: Combination Figure 1 The present embodiment is described. A low-temperature corrosion control device for the tail heating surface of a waste incineration waste heat boiler of the present embodiment comprises a main water supply circuit, a water supply heating circuit and a regulating circuit, wherein the main water supply circuit is respectively connected with the water supply heating circuit and the regulating circuit; the present invention can adapt to various load conditions during the operation of the boiler, realize that the exhaust gas temperature of the boiler is fully controllable, effectively control the low-temperature corrosion of the tail heating surface of the boiler, extend the service life of the heating surface of the boiler, effectively reduce the heat loss of the exhaust gas, improve the efficiency of the boiler, and make the boiler pollutant emission meet the standards;

[0022] The main water supply circuit includes an air preheater 1, an economizer 2, a main regulating valve 5 and a boiler drum 6, wherein the main regulating valve 5, the air preheater 1, the economizer 2 and the boiler drum 6 are sequentially connected to form the main water supply circuit;

[0023] It also includes a first regulating valve 4, the air preheater 1 and the first regulating valve 4 are arranged in parallel, the inlets of the air preheater 1 and the first regulating valve 4 are connected to the main regulating valve 5 and the air preheater 1 through a first three-way pipe, and the outlets of the air preheater 1 and the first regulating valve 4 are connected to the air preheater 1 and the economizer 2 through a second three-way pipe;

[0024] The main regulating valve 5 is a three-way regulating valve, and the main regulating valve 5 has a valve main inlet 51, a first valve outlet 52 and a second valve outlet 53;

[0025] The drum 6 has a boiler main inlet 61, a heating water pipeline outlet 62 and a heating water pipeline inlet 63;

[0026] The valve main inlet 51, the second valve outlet 53, the main line pipe 7, the air preheater 1 arranged in parallel, the first regulating valve 4, the economizer 2, and the boiler main inlet 61 are connected in sequence to form a main water supply line;

[0027] The valve main inlet 51, the first valve outlet 52, the heating water pipeline inlet 63, the heating water pipeline outlet 62, and the main pipeline 7 are connected in sequence to form a water heating circuit;

[0028] The main line pipe 7, the second regulating valve 3, and the main inlet 61 of the boiler are connected in sequence to form a regulating line;

[0029] The connection between the heating water pipeline outlet 62 and the main pipeline 7 is located in front of the connection between the second regulating valve 3 and the main pipeline 7;

[0030] The air preheater 1 uses feed water to heat the air and is not in direct contact with the waste incineration flue gas. Instead, it is arranged outside the boiler flue, which effectively reduces the corrosion problem of the air preheater caused by harmful components in the flue gas;

[0031] When the boiler load is high and the flue gas volume is large, the first valve outlet 52 of the main regulating valve 5 is closed, and the opening of the second regulating valve 3 is reduced. The main feed water of the boiler flows through the main valve inlet 51 and the second valve outlet 53 into the air preheater 1 and the economizer 2, which can increase the water flow through the air preheater 1 and the economizer 2 and reduce the tail flue gas temperature;

[0032] When the boiler load is low and the flue gas volume is low, the first valve outlet 52 of the main regulating valve 5 is opened, and the opening of the electric regulating valve 3 is increased. A part of the boiler main feed water flows through the valve main inlet 51 and the second valve outlet 53 to enter the air preheater 1 and the economizer 2, and another part of the boiler main feed water flows through the valve main inlet 51 and the first valve outlet 52 to enter the feed water heating circuit. The heated water enters the air preheater 1 through the main circuit pipe 7, increasing the feed water temperature entering the air preheater 1 and the economizer 2, increasing the flue gas temperature of the tail heating surface, and controlling the corrosion of the tail heating surface;

[0033] When the boiler primary air volume fluctuates, the inlet water temperature of the economizer 2 is controlled by adjusting the opening of the first regulating valve 4 to prevent low-temperature corrosion caused by too low economizer water temperature.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0035] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0036] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0037] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0038] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0039] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A low-temperature corrosion control device for the tail heating surface of a waste incineration waste heat boiler, characterized in that: It includes a main water supply circuit, a water supply heating circuit and a regulating circuit, wherein the main water supply circuit is connected with the water supply heating circuit and the regulating circuit respectively; The main water supply circuit comprises an air preheater (1), an economizer (2), a main regulating valve (5) and a boiler drum (6), wherein the main regulating valve (5), the air preheater (1), the economizer (2) and the boiler drum (6) are connected in sequence to form the main water supply circuit; The device for controlling low-temperature corrosion of the rear heating surface of a waste incineration waste heat boiler further comprises a first regulating valve (4), and the air preheater (1) and the first regulating valve (4) are arranged in parallel; The regulating valve (5) is a three-way regulating valve, and the regulating valve (5) has a valve main inlet (51), a first valve outlet (52) and a second valve outlet (53); The boiler drum (6) has a boiler main inlet (61), a heating water pipeline outlet (62) and a heating water pipeline inlet (63); The valve main inlet (51), the second valve outlet (53), the main pipeline (7), the air preheater (1) arranged in parallel and the first regulating valve (4), the economizer (2), and the boiler main inlet (61) are connected in sequence to form a main water supply path; The valve main inlet (51), the first valve outlet (52), the heating water pipeline inlet (63), the heating water pipeline outlet (62), and the main pipeline (7) are connected in sequence to form a water supply heating circuit; The main line pipe (7), the second regulating valve (3), and the main inlet (61) of the boiler are connected in sequence to form a regulating line; The connection point between the heating water pipeline outlet (62) and the main pipeline (7) is located in front of the connection point between the second regulating valve (3) and the main pipeline (7).

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