Double-hearth structure suitable for biomass organic heat carrier boiler

Abstract

The utility model discloses a double-hearth structure suitable for a biomass organic heat carrier boiler, and belongs to the technical field of boilers. The boiler comprises a boiler body, a first hearth and a second hearth are arranged in the boiler body, a circle of surrounding front hearth coil pipe is arranged in the first hearth, a circle of surrounding rear hearth coil pipe is arranged in the second hearth, and the front hearth coil pipe is connected with the rear hearth coil pipe through a connecting pipeline. According to the utility model, the hearth return stroke design is added, so that volatile components are fully combusted to avoid open fire in a convection section; the radiation heating area is increased, so that the temperature of flue gas entering the convection section is reduced to prevent coking blockage; and the boiler efficiency is improved, the fault risk is reduced, pollutant emission is reduced, and the method is suitable for various boilers combusting biomass fuel, and has positive significance and wide application prospects for biomass energy utilization and boiler industry development.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of boiler, concretely relates to a double hearth structure suitable for biomass organic heat carrier boiler. BACKGROUND

[0002] With the global attention to renewable energy and the increasing environmental protection requirements, biomass energy as a clean and renewable energy resource is more and more widely used in the field of energy. As an important equipment for converting biomass energy into heat energy, the performance improvement of biomass organic heat carrier boiler is of great significance to improve energy utilization efficiency and reduce environmental pollution.

[0003] However, in the actual operation process, biomass fuel combustion faces many technical problems. The moisture content of biomass fuel is high and unstable, and a large amount of heat is absorbed during combustion, which reduces the temperature of the combustion area. In addition, the particle size is uneven, small particles are easily carried out by flue gas, and large particles are not fully combusted, which leads to energy waste and seriously affects the energy utilization efficiency of the boiler. The alkali metal and mineral components contained in it react to form low-melting eutectic at high temperature, and condense into coke on the heating surface. The thickening of coke reduces the heat transfer efficiency, increases fuel consumption and operating cost, and may also cause local overheating of the heating surface, leading to pipe deformation, damage and even pipe explosion and other safety accidents. In terms of combustion air distribution, insufficient air supply produces a large amount of CO (carbon monoxide), which not only wastes energy but also pollutes the environment and harms health; excessive air supply reduces CO generation but increases flue gas oxygen content, increases flue gas heat loss, reduces thermal efficiency and aggravates nitrogen oxide generation and environmental pollution. These problems reduce the thermal efficiency of the boiler, increase the operating cost, and also threaten the environment and equipment safety.

[0004] Therefore, in view of the problems of biomass fuel combustion, energy waste, easy coking affecting normal operation of the boiler, and abnormal phenomena of high CO and high oxygen, the utility model provides a double hearth structure suitable for biomass organic heat carrier boiler, which improves the overall performance and operation reliability of the boiler. UTILITY MODEL CONTENTS

[0005] In view of the problems mentioned in the background art, the utility model provides a double hearth structure suitable for biomass organic heat carrier boiler, which can prolong the residence time of volatile matter in the radiation section, ensure full combustion and avoid open fire in the convection section; can increase the radiation heating area of the boiler, so that the flue gas temperature entering the convection section is reduced to about 800℃, preventing the flue gas side ash from sticking to the pipe after melting and blocking the flue gas passage; can increase the combustion space and time, so that the fuel is fully combusted, preventing the abnormal phenomenon of high CO and high oxygen.

[0006] Technical scheme: in order to solve the above technical problems, the utility model adopts the following technical scheme:

[0007] The utility model provides a double hearth structure suitable for biomass organic heat carrier boiler, including the boiler body, be equipped with first hearth and second hearth in the boiler body, be equipped with a circle of encircle's front hearth coil pipe in first hearth, be equipped with a circle of encircle's rear hearth coil pipe in second hearth, and the front hearth coil pipe is connected with rear hearth coil pipe through connecting pipeline.

[0008] As preferred, the front hearth coil pipe and the rear hearth coil pipe are located in the radiation section of the boiler body.

[0009] As preferred, a low point oil drain is provided on the connecting pipeline.

[0010] As preferred, a bottom bracket is provided at the lower end of the connecting pipeline and the front hearth coil pipe, and a limiting plate is provided at the side end of the front hearth coil pipe and the rear hearth coil pipe.

[0011] As preferred, a steel frame is provided in the boiler body; the front hearth coil pipe and the rear hearth coil pipe are fixed on the steel frame by the bottom bracket and the limiting plate.

[0012] Advantages: Compared with the prior art, the utility model has the following advantages:

[0013] (1) The utility model has the advantages of improving boiler efficiency, reducing fault risk and reducing pollutant emissions, and is suitable for various biomass fuel boilers, which has positive significance and broad application prospect for biomass energy utilization and boiler industry development.

[0014] (2) The structure of the utility model aims to solve the problems of insufficient combustion, easy coking, high CO and high oxygen during biomass fuel combustion. By increasing the hearth return design, the residence time of volatile matter in the radiation section can be prolonged, ensuring complete combustion and avoiding open flames in the convection section; the boiler radiation heating area can be increased, so that the flue gas temperature entering the convection section is reduced to about 800 DEG C, preventing the flue gas side ash from sticking to the pipe after melting and blocking the flue gas passage; the combustion space and time can be increased, so that the fuel can be fully burned, preventing the abnormal phenomenon of high CO and high oxygen. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is the front view of the double hearth structure suitable for biomass organic heat carrier boiler of the utility model;

[0016] Figure 2 is the top view of the double hearth structure suitable for biomass organic heat carrier boiler of the utility model;

[0017] Figure 3 is the left view of the double hearth structure suitable for biomass organic heat carrier boiler of the utility model;

[0018] Figure 4 is Figure 1 A-A sectional view in the figure.

[0019] In the diagram: 1. Front furnace coil; 2. Rear furnace coil; 3. Connecting pipe; 4. Low point oil drain port; 5. Bottom bracket; 6. Limiting plate. Detailed Implementation

[0020] The present invention will be further illustrated below with reference to specific embodiments. The embodiments are implemented based on the technical solution of the present invention. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0021] like Figures 1-4 As shown, the dual-furnace structure for biomass organic heat carrier boilers provided in this embodiment mainly includes a boiler body, a first furnace, a second furnace, a connecting pipe, a low-point oil drain port 4, a bottom bracket 5, a limiting plate 6, and a steel frame, all located within the boiler body.

[0022] The first furnace chamber is equipped with a front furnace coil 1, and the second furnace chamber is equipped with a rear furnace coil 2. The front furnace coil 1 is connected to the rear furnace coil 2 through a connecting pipe 3. Both the front furnace coil 1 and the rear furnace coil 2 are mounted on a steel frame.

[0023] In this embodiment, the front furnace coil 1 and the rear furnace coil 2 are located in the radiant section of the boiler body, and the space of the front furnace coil 1 is larger than that of the rear furnace coil 2. The front furnace coil 1 has sufficient combustion space to facilitate the complete combustion of biomass energy, while also avoiding excessive radiant heat flux density. The structure of the rear furnace coil 2 can be appropriately compact to avoid excessive heating area and unnecessary waste.

[0024] like Figure 1 , Figure 2 As shown, one end of the connecting pipe 3 is connected to the front furnace coil 1, and the other end is connected to the rear furnace coil 2.

[0025] like Figure 1 , Figure 3 As shown, a low-point drain port 4 is provided at the lowest point of the connecting pipeline. In this embodiment, there are multiple low-point drain ports 4.

[0026] like Figure 4 As shown, a bottom bracket 5 is provided at the lower end of the connecting pipe 3 and the front furnace coil 1, and a limiting plate 6 is provided at the side end of the front furnace coil 1 and the rear furnace coil 2. The bottom bracket 5 and the limiting plate 6 are used to stably fix the front furnace coil 1 and the rear furnace coil 2 on the steel frame inside the boiler body.

[0027] In this embodiment, there are multiple bottom brackets 5.

[0028] In the embodiment, the bracket and the limiting plate can be fixed to the front hearth coil pipe and the rear hearth coil pipe in a sliding connection mode, so that the coil pipes can freely expand after being heated.

[0029] The working principle or use flow of the utility model is as follows:

[0030] The flue gas flow is as follows: the biomass fuel is combusted in the first hearth to generate high-temperature flue gas; the flue gas flows from bottom to top due to the thermal buoyancy effect; the flue gas transfers heat to the front hearth coil pipe 1 in a convection and radiation manner, so that the organic heat carrier in the coil pipe absorbs heat and is heated, and the temperature of the flue gas is reduced; then the flue gas changes the flow direction and flows from top to bottom through the rear hearth coil pipe 2, continues to exchange heat with the rear hearth coil pipe 2, further releases heat, and then enters the convection section from the lower part, continues to exchange heat with the heating surface of the convection section, and is discharged after the temperature of the flue gas is reduced to a suitable flue gas discharge temperature, and the above-mentioned mode is sequentially arranged in the flue gas flow.

[0031] The organic heat carrier flow is as follows: the organic heat carrier first enters the convection section of the boiler body, absorbs heat by convection heat exchange with the high-temperature flue gas in the convection section, and the temperature is preliminarily increased; then the heat carrier flows into the rear hearth coil pipe 2, the rear hearth coil pipe 2 is compact in structure and is located at a specific position in the flue gas flow, can efficiently absorb heat from the flue gas, and further heats the heat carrier. Then the heat carrier enters the front hearth coil pipe 1 of the body through the communication pipeline. The front hearth coil pipe 1 has a large space, provides a good heating condition for the heat carrier in the environment of fully combusting the biomass, and the heat carrier absorbs more heat to reach a higher temperature to meet the subsequent heating or energy conversion requirements. The multiple low-point oil discharge ports 4 at the lowest point of the communication pipeline can discharge impurities or condensate that may exist when necessary, so as to ensure the quality of the heat carrier and the smooth circulation.

[0032] The double hearth structure of the utility model effectively solves the problems of insufficient combustion, easy coking, high CO and high oxygen during the combustion of the biomass fuel; has the advantages of improving the boiler efficiency, reducing the fault risk and reducing the pollutant emission, and is suitable for various biomass fuel boilers, has a positive significance for the utilization of biomass energy and the development of the boiler industry, and has a broad application prospect.

[0033] The above-mentioned is only the preferred embodiment of the utility model, and it should be pointed out that, for ordinary skilled persons in the technical field, some improvements and decorations can be made without departing from the principle of the utility model, and these improvements and decorations should also be regarded as the protection range of the utility model.

Claims

1. A double furnace structure suitable for biomass organic heat carrier boiler, comprising a boiler body, characterized in that: The boiler body is internally provided with a first furnace and a second furnace, the first furnace is internally provided with a ring of surrounding front furnace coil pipe (1), the second furnace is internally provided with a ring of surrounding rear furnace coil pipe (2), the front furnace coil pipe (1) is connected with the rear furnace coil pipe (2) through connecting pipeline (3).

2. The double furnace structure suitable for biomass organic heat carrier boiler according to claim 1, characterized in that: The front furnace coil pipe (1) and the rear furnace coil pipe (2) are located at the radiation section of the boiler body.

3. The double furnace structure suitable for biomass organic heat carrier boiler according to claim 1, characterized in that: A low point oil discharge port (4) is arranged at the upper end of the connecting pipeline (3).

4. The double furnace structure suitable for biomass organic heat carrier boiler according to claim 2, characterized in that: A bottom bracket (5) is arranged at the lower end of the connecting pipeline (3) and the front furnace coil pipe (1), and a limiting plate (6) is arranged at the side end of the front furnace coil pipe (1) and the rear furnace coil pipe (2).

5. The double furnace structure suitable for biomass organic heat carrier boiler according to claim 1, characterized in that: A steel frame is arranged in the boiler body, and the front furnace coil pipe (1) and the rear furnace coil pipe (2) are fixed on the steel frame by the bottom bracket (5) and the limiting plate (6).

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