CN210153772U

CN210153772U - Original-state straw moving bed boiler

Info

Publication number: CN210153772U
Application number: CN201920874278.XU
Authority: CN
Inventors: 李永平; 张春明; 赵延伟
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-06-11
Filing date: 2019-06-11
Publication date: 2020-03-17
Anticipated expiration: 2029-06-11

Abstract

The utility model discloses a raw straw moving bed boiler, wherein a chain grate, a front arch and a rear arch are sequentially arranged inside a hearth structure; the air distribution system sequentially comprises a first fan and an air channel thereof for generating primary combustion-supporting air upwards along the chain grate, a second fan and an air channel thereof for respectively generating secondary combustion-supporting air relatively and horizontally along two sides of the main combustion area, and a third fan and an air channel thereof for horizontally generating tertiary combustion-supporting air from left to right along the upper end of the front arch. The utility model discloses, burn on the traveling grate stoker with the original form straw bale, realize clean burning, the wide application is in the large and medium-sized boiler equipment of trades such as industrial production and heat supply heating.

Description

Original-state straw moving bed boiler

Technical Field

The utility model relates to a clean combustion apparatus, concretely relates to original state straw removes bed boiler.

Background

As is well known, the annual crop straw production in China is more than 7 hundred million tons, and the comprehensive utilization rate is low. Besides being used in industries such as paper making, feed processing and biogas, other areas are deeply buried, and a large amount of substances are incinerated in the field in all areas, so that haze is generated and cities are polluted.

The straws belong to renewable clean fuel, the content of nitrogen and sulfur is far lower than that of coal, the heat value of each ton of straws is equivalent to half ton of standard coal, the emission of carbon dioxide after combustion belongs to carbon cycle of the nature, and no pollution is formed. In order to realize clean combustion of straws, the straws are secondarily processed to be briquetted or granular fuel in the market at present, and the briquetted or granular fuel is widely applied to production and life.

However, the development of the existing straw boiler encounters a certain bottleneck, which is mainly reflected in the following aspects

1. Fuel aspect

(1) The straw power generation boiler belongs to a large-capacity boiler, straws need to be crushed and sent to the boiler for combustion, and the straw power generation boiler has the disadvantages of more auxiliary equipment, complex process flow, large storage yard and high transportation cost;

(2) and a straw forming plant is built, briquettes and granular fuel are produced, and the secondary processing cost is increased.

2. Aspect of combustion

(1) The combustion equipment generally adopts two forms of a fixed grate and a rotary grate, and has the common characteristic that the boiler has small capacity, generally less than four tons per hour, and clinker of a fire bed is easy to harden and difficult to remove at high temperature, so that the boiler cannot operate;

(2) the air supply of the boiler adopts a single furnace bottom air supply mode, and an aerodynamic field can not be reasonably organized according to the fuel characteristics, so that combustible materials can not be fully burnt.

Therefore, the existing straw boiler has the following defects:

1. the capacity of the boiler is bipolar, and no large and medium-sized industrial and civil boiler products exist;

2. the ash slag hardening of the fire grate is serious, and smoke scale is hung on the heating surface;

3. the briquettes or particles have higher density and are not easy to burn through, and the heat loss of the fuel is increased;

4. the boiler has single air distribution, can not well organize oxygen supply, and has uneven and insufficient combustion.

In conclusion, a novel original-state straw boiler needs to be designed at present, the purposes of clean combustion and full combustion are achieved, coking is avoided, and ash residues are few.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problems that the design of the existing straw boiler is unreasonable, the cost is high, the combustion is insufficient, and the coking is easy.

In order to solve the technical problem, the utility model adopts the technical scheme that an original straw removes bed boiler is provided, including boiler body and the furnace structure that from top to bottom arranges, the inside of furnace structure is equipped with by supreme down in proper order:

the chain grate is used for supporting and conveying the straw bales and is arranged at the bottom of the hearth structure;

the front arch is arranged above the fuel inlet of the traveling grate stoker and gradually inclines upwards from left to right;

the rear arch is arranged above the other side of the traveling grate relative to the fuel inlet and gradually inclines upwards from right to left, the rear arch is arranged at the middle rear part of the hearth structure, an opening is formed between the front arch and the top of the rear arch, and a preheating zone, a main combustion zone and an ember zone are sequentially arranged on the traveling grate from the front arch to the rear arch;

the air distribution system sequentially comprises a first fan and an air channel thereof which generate primary combustion-supporting air upwards along the bottom of the chain grate, a second fan and an air channel thereof which respectively generate secondary combustion-supporting air relatively and horizontally along two sides of the main combustion area, and a third fan and an air channel thereof which horizontally generate tertiary combustion-supporting air from left to right along the upper end of the front arch.

In the scheme, the lower part of the left end of the hearth structure is provided with a boiler feeding device for accommodating straw bales to enter, and the boiler feeding device comprises a rotating door hinged to the head of the chain grate.

In the scheme, the primary combustion-supporting air is distributed towards the preheating zone, the main combustion zone and the burnout zone.

In the above scheme, the first fan, the second fan and the air duct thereof are arranged outside or inside the furnace structure, and the third fan and the air duct thereof are arranged in the front arch and the furnace wall above the front arch or outside the furnace structure.

In the scheme, the secondary combustion-supporting air is horizontally arranged in parallel from top to bottom in three rows respectively.

In the above scheme, the air volume of the first fan, the second fan and the third fan is adjustable.

In the above scheme, the secondary combustion-supporting air is blown towards the center from two side wall surfaces of the main combustion area respectively, and the wind direction of the secondary combustion-supporting air is perpendicular to the running direction of the chain grate.

The utility model discloses, burn on the traveling grate stoker with the original form straw bale, realize clean burning, the wide application is in the large and medium-sized boiler equipment of trades such as industrial production and heat supply heating.

Drawings

Fig. 1 is a schematic view of the internal structure and wind direction of the present invention.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.

The utility model discloses a raw straw moving bed boiler, and technical personnel in the field can suitably improve technological parameters and realize by referring to the contents in the text. It is expressly noted that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be included in the invention and it is apparent to those skilled in the art that the inventive technique can be practiced and applied by modifying or appropriately combining the teachings herein without departing from the spirit and scope of the invention.

In the present application, unless otherwise specified, scientific and technical terms used herein have the meanings as commonly understood by one of ordinary skill in the art.

The utility model discloses the former attitude bale straw of boiler design fuel selection, consequently need not carry out secondary operation to the straw.

The original packed straw refers to that the straw is directly harvested and packed in the field by a harvester without secondary processing into briquettes or particles. The heat value of the packed straw is generally about 3500 Kcal, the volatile component is above 60%, the ash content is about 10%, the average sulfur content is not more than 0.4%, and the water content is about 10%. Comprehensive factors show that the fuel characteristics of the straw are completely suitable for being used as boiler fuel.

People who have rural life experience know that the oven of the heated kang burns the original straws without coking, and the burnt ash is loose. The true reason for biomass fuel combustion coking is that the fuel is mixed with impurities such as soil or building materials, the more impurities, the more obvious coking, and the more serious the formed biomass fuel.

As shown in figure 1, the utility model provides a pair of original straw removes bed boiler, including boiler body 8 and the furnace structure that from top to bottom arranges, the inside of furnace structure is by supreme chain grate 7 and the furnace arch of being equipped with in proper order down, and the furnace arch is including preceding arch 3 and back arch 6. The chain grate 7 is used for supporting and transporting the straw bales 2 and is arranged at the bottom of the hearth structure, and the chain grate is selected by the utility model, firstly, the chain grate has good coke breaking capacity and wide speed regulation range and is suitable for straw combustion; secondly, the chain grates matched with the existing coal-fired grate firing boiler can be designed into the original straw-fired boiler, thereby greatly expanding the range of the straw-fired boiler.

The area between the traveling grate 7 and the whole furnace arch and from the front arch 3 to the rear arch 6 is sequentially divided into a preheating area 9, a main combustion area 11 and an ember area 10, the front arch 3 is arranged above the fuel inlet of the traveling grate 7 and gradually inclines upwards from left to right, and the area between the front arch 3 and the traveling grate 7 comprises the preheating area 9 and a part of the main combustion area 11; the rear arch 6 is arranged above the middle rear part of the traveling grate 7 and gradually inclines upwards from right to left, the area between the rear arch 6 and the traveling grate 7 comprises a part of main combustion area 11 and an after-combustion area 10, openings are formed between the tops of the front arch 3 and the rear arch 6 at intervals, high-temperature flue gas can be discharged into a hearth upwards from the openings and then fully combusted, and the area between the openings and the traveling grate 7 comprises a part of main combustion area 11.

The inverted V-shaped furnace arch can play a role in enhancing the mixing of airflow in the furnace and reasonably organizing the flow and the heat radiation of the airflow, thereby achieving the purposes of timely ignition, continuous and stable combustion and full burn-off.

The lower part of the left end of the hearth structure is provided with a boiler feeding device 1 for accommodating straw bales 2, the boiler feeding device comprises a rotating door hinged to the head of the chain grate, and the rotating door can rotate and open along the dotted line in the figure. Straw bales 2 (for example, cylindrical corn bales, straw 1.2 meters in diameter and 1.25 meters in height) are transported from the yard to the boiler feeder 1 by a forklift or an automatic conveyor and then enter the traveling grate 7 for combustion.

The air distribution system sequentially comprises a first fan, a second fan, a third fan and respective air channels, the air quantity of the first fan, the air quantity of the second fan and the air quantity of the third fan can be adjusted according to the combustion condition, the first fan, the second fan and the air channels can be arranged outside or inside the hearth structure according to the actual design and use condition, and the third fan and the air channels can be arranged in the furnace wall above the front arch 3 and the front arch 3 or outside the hearth structure.

As shown in fig. 1, the first fan can generate primary combustion air 12 blowing upward along the bottom of the traveling grate 7 through its air duct, the second fan can generate secondary combustion air 5 blowing horizontally along both sides of the main combustion area 11, that is, the secondary combustion air 5 blows toward the center from both side walls of the main combustion area 11, and the wind direction of the secondary combustion air 5 is perpendicular to the traveling direction of the traveling grate 7 (i.e., perpendicular to the plane direction of the drawing), and the third fan can generate tertiary combustion air 4 blowing horizontally from left to right along the upper end of the front arch 3 through its air duct. Preferably, the primary combustion air 12 is distributed differently towards the preheating zone 9, the main combustion zone 11 and the ember zone 10, so that the air volume is supplied as required. The secondary combustion-supporting air 5 is horizontally arranged in parallel from top to bottom in three rows, and the tertiary combustion-supporting air 4 is horizontally arranged in parallel from left to right, so that the combustible substances are fully combusted.

The utility model provides a cloth wind system principle and effect as follows:

(1) primary air for grate

Controlled by the first fan, the air quantity of the preheating zone, the main combustion zone and the burnout zone can be adjusted, and oxygen supply combustion at the bottom of the bale fuel is completed.

(2) And two side secondary air

The secondary air is distributed in the main combustion areas at two sides of the boiler under the control of the second fan, the air quantity is adjustable, and oxygen supply combustion of the middle upper part of the bale fuel is completed.

(3) Tertiary air for opening

The air quantity can be adjusted at the upper end of the front arch of the boiler under the control of a third fan, and oxygen is provided for unburned combustible substances outside the arch area.

As the thickness of the bundled straws is more than one meter and is relatively compact, the bundle can be blown loose by high-pressure wind power formed by the multi-stage combined air inlet mode, high-temperature smoke and wind mixed gas is fed into the bundle, the uniform air inlet of the whole fuel layer is ensured, and the nearly complete combustion is achieved.

The technical effects of the utility model:

1. the utility model uses the original straw bale, does not need secondary processing, and greatly reduces the comprehensive cost of fuel.

2. The application of the chain grate can enlarge the boiler and fill the blank of straw burning of industrial boilers.

3. The multi-stage combined air distribution and the design of the large-water-cooling-degree hearth realize a low-temperature combustion control mode and inhibit the generation of nitrogen oxides.

4. By adopting a low-temperature combustion technology and a chain grate, the straw is not coked after being combusted, and loose ash is formed.

5. The fire grate pieces do not need to be made of heat-resistant cast iron, so that the cost of the chain fire grate is greatly reduced.

6. The straw ash is commonly called as plant ash, is rich in nitrogen, phosphorus and potassium, is a good farmland fertilizer, can be returned to the field on site and is fertile to soil.

The utility model discloses an application case

The utility model relates to a make a 10.5MW ordinary pressure hot water boiler, use a heating period in 2018 ~ 2019 in the town of the big hills in Jilin province princess mountain city, gained good effect.

The heat supply area of the boiler is 14 ten thousand square meters, and the boiler comprises a landlord home, a landlord apartment, an aged-care community and the like. The boiler adopts discontinuous operation, and the heat supply network adopts indirect heating mode, sets up the heat transfer station. The boiler has the advantages of convenient ignition, simple and flexible operation, quick start and temperature rise, less ash and slag and no coking of the grate. After the heating period, the heating surface and the pipe wall are inspected, a small amount of ash and scale hung on the heating surface and blown by compressed air, and the heating surface and the pipe wall can be removed, so that the heating device is particularly convenient.

In the whole heating period, 3 thousands of bags of corn straws are used for burning by the boiler, the total amount is 7500 tons, and the direct fuel cost is 135 ten thousand yuan. If a coal-fired boiler is adopted, at least 3700 tons of coal is consumed, the direct fuel cost is more than 200 ten thousand yuan, and the economic benefit is very obvious in comparison from the fuel aspect.

The present invention is not limited to the above best mode, and any person should learn the structural changes made under the teaching of the present invention, all with the present invention has the same or similar technical solution, all fall into the protection scope of the present invention.

Claims

1. The utility model provides an original state straw removes bed boiler, includes boiler body and the furnace structure that from top to bottom arranges, its characterized in that, the inside of furnace structure is equipped with by supreme down in proper order:

2. The raw straw moving bed boiler according to claim 1, wherein a boiler feeding device for accommodating straw bales is arranged at the lower part of the left end of the hearth structure and comprises a rotating door hinged to the head of the chain grate.

3. The raw straw moving bed boiler according to claim 1, wherein the primary combustion air is distributed toward the preheating zone, the main combustion zone and the burnout zone.

4. The raw straw moving bed boiler according to claim 1, wherein the first fan, the second fan and the air duct thereof are disposed outside or inside the furnace structure, and the third fan and the air duct thereof are disposed in the front arch and the furnace wall above the front arch or outside the furnace structure.

5. The raw straw moving bed boiler according to claim 1, wherein the secondary combustion supporting air is horizontally arranged in three rows from top to bottom in parallel.

6. The raw straw moving bed boiler according to claim 1, wherein the air volume of the first fan, the second fan and the third fan is adjustable.

7. The raw straw moving bed boiler according to claim 1, wherein the secondary combustion-supporting air is blown towards the center from two side wall surfaces of the main combustion area, and the wind direction of the secondary combustion-supporting air is perpendicular to the running direction of the chain grate.