阅读说明：本技术 一种危险废物焚烧尾气余热锅炉 (Hazardous waste burns tail gas exhaust-heat boiler ) 是由 吴迪 姜洋 程佳 穆建华 徐健 杜文飞 夏广旭 陈治新 孙锦辉 于 2021-08-04 设计创作，主要内容包括：本发明涉及余热锅炉技术领域,尤其涉及一种危险废物焚烧尾气余热锅炉,炉体为立式结构,包括锅筒、水冷壁、炉墙、上升管、下降管、进口烟道、出口烟道和灰斗,水冷壁为全膜式壁结构,炉体内炉膛被垂直设置的水冷壁分成进口区和出口区,形成进口区与出口区底部相连通的U形流道；在炉膛进口区的900-1050℃区域内设有脱硝设备安装孔。本发明的优点为：1)U型烟道结构,有利于灰尘的沉降和收集。2)全膜式壁结构,结构简单、密封效果好。3)灰尘易被沉降和收集,防止二噁英类物质分解后的再合成。4)在烟气温度900～1050℃的温度区域设置有脱硝装置,可使70%～110%额定负荷实现炉内脱硝,满足环保要求。(The invention relates to the technical field of waste heat boilers, in particular to a hazardous waste incineration tail gas waste heat boiler, wherein a boiler body is of a vertical structure and comprises a boiler barrel, a water-cooled wall, a boiler wall, an ascending pipe, a descending pipe, an inlet flue, an outlet flue and an ash bucket, wherein the water-cooled wall is of a full-film wall structure, a hearth in the boiler body is divided into an inlet area and an outlet area by the vertically arranged water-cooled wall, and a U-shaped flow channel communicated with the bottoms of the inlet area and the outlet area is formed; denitration equipment mounting holes are arranged in the region of the inlet area of the hearth at the temperature of 900-1050 ℃. The invention has the advantages that: 1) the U-shaped flue structure is beneficial to the sedimentation and collection of dust. 2) The full-film wall structure has simple structure and good sealing effect. 3) The dust is easy to settle and collect, and the resynthesis of dioxin substances after decomposition is prevented. 4) The denitration device is arranged in a temperature area with the flue gas temperature of 900-1050 ℃, so that denitration in the furnace can be realized at 70-110% of rated load, and the environmental protection requirement is met.)

1. A dangerous waste incineration tail gas waste heat boiler, the furnace body is a vertical structure, set up in the steel frame vertically, there are multiple layers of platforms on the steel frame, there are furnace walls on the inboard of the steel frame, including boiler drum, water-cooled wall, furnace wall, riser, downcomer, inlet flue, outlet flue and ash bucket, characterized by that, the boiler drum locates at the top end of the furnace body, the said water-cooled wall is the structure of the full membrane wall, the furnace chamber is divided into inlet area and outlet area by the water-cooled wall set up vertically in the furnace body, form the U-shaped flow path that the inlet area communicates with bottom of the outlet area; the top of the inlet area is provided with an inlet flue, the top of the outlet area is provided with an outlet flue, and the bottoms of the inlet area and the outlet area are respectively provided with an ash hopper; a plurality of denitration device mounting holes are arranged in a region of 1050 ℃ in the 900-plus-one region of the hearth inlet region, the denitration device mounting holes are distributed in an array mode, and the denitration device mounting holes are connected with denitration devices through pipelines.

2. The hazardous waste incineration tail gas waste heat boiler as claimed in claim 1, wherein the inlet flue is horizontally opened, the outlet flue is vertically opened, and the highest point elevation of the inlet flue with the same caliber as the outlet flue is lower than that of the outlet flue by 250-450 mm.

3. The hazardous waste incineration tail gas waste heat boiler according to claim 1, wherein the full-membrane water wall is formed by welding and connecting steel pipes and flat steel, and no gap is formed between the adjacent steel pipes.

4. The hazardous waste incineration tail gas waste heat boiler according to claim 1, wherein the side wall of the ash hopper is at an angle of 17.5-30 ° to the vertical.

5. The hazardous waste incineration tail gas waste heat boiler according to claim 1, wherein the inlet zone and the outlet zone are rectangular in cross section, and the ratio of the cross sectional areas of the inlet zone and the outlet zone is 1.2-1.6: 1.

6. The hazardous waste incineration tail gas waste heat boiler of claim 1, wherein the denitration device is an SNCR denitration device.

7. The hazardous waste incineration tail gas waste heat boiler of claim 1, wherein the riser pipe is connected with the drum with a 90-degree corner formed by connecting a vertical section and a horizontal section.

8. The hazardous waste incineration tail gas waste heat boiler as claimed in claim 1, wherein the outside of the water wall is provided with a composite insulation layer consisting of an aluminum silicate refractory fiber layer and an outer guard plate, the thickness of the composite insulation layer is 150-350mm, and the thickness of the aluminum silicate refractory fiber layer is not less than 120 mm.

9. The hazardous waste incineration tail gas waste heat boiler according to claim 1, wherein the inlet area and the outlet area are provided with a plurality of soot blowing observation holes from top to bottom, and the soot blowing observation holes are provided with matching structures matched with a shock wave soot blower or an elastic vibrator.

Technical Field

The invention relates to the technical field of waste heat boilers, in particular to a hazardous waste incineration tail gas waste heat boiler.

Background

The existing hazardous waste incineration waste heat boiler has some treatment measures on strong coking cohesive ash contained in flue gas, but has some problems for stably and efficiently operating a flue gas cooling system. The utility model discloses a chinese utility model patent of application number 200720089181.5 discloses a hazardous waste burns burning furnace exhaust-heat boiler, and the boiler adopts full membrane formula water-cooling wall structure, does not arrange the convection current in the radiation heat transfer flue that the membrane type water-cooling wall constitutes and receives the hot side, has avoided the sticky ash that binds of strong coking nature to concentrate on the convection current receives the hot side, blocks up the flue, and its weak point is: when the flue gas flow velocity in the flue at the flue gas outlet end is smaller than that in the flue at the flue gas inlet end, the flue gas flow velocity in the front flue and the rear flue of the furnace body is changed greatly, so that the heat exchange efficiency in the flue of the furnace body is low, the temperature of the flue gas outlet is high, the effective utilization rate of flue gas heat is low, the flue gas flow velocity is low, and the effect of removing dust by means of flue gas turning inertia can be discounted.

The utility model discloses a chinese utility model patent application No. 201920846249.2 discloses a hazardous waste burns and uses four return heat recovery boilers, including vertical heat recovery device body and the drum on its upper portion, the heat recovery device body includes that the inner wall is the heat transfer cavity of membrane water-cooling wall, be provided with on the heat transfer cavity and prevent deposition and gas cleaning device, the inside W-shaped flue gas passageway that separates into four return strokes by the membrane water-cooling wall of heat transfer cavity, the inner wall that the heat recovery device body and flue gas passageway contacted is the membrane water-cooling wall, the membrane water-cooling wall is connected with the drum for the high temperature flue gas carries out the heat exchange in leading into water and the flue gas passageway. The defects of the scheme are that the W-shaped flow channel has large resistance, the problem that the flow velocity of the flue gas outlet end is smaller than that of the inlet is still existed, and the effective utilization rate of flue gas heat is low.

Disclosure of Invention

The invention aims to provide a hazardous waste incineration tail gas waste heat boiler, which overcomes the defects of the prior art, a denitration device is arranged in the boiler, and a water cooling system adopts a full-film wall structure, so that the sealing effect is improved, and the structure is simplified; the vertical furnace body reduces the floor area; the bottom of the U-shaped heat exchange tube is provided with an ash bucket, so that the resynthesis of decomposed dioxin-like substances is prevented, and the environmental protection requirement is met.

In order to realize the purpose, the invention is realized by adopting the following technical scheme:

a dangerous waste incineration tail gas waste heat boiler, the furnace body is a vertical structure, set up in the steel frame vertically, there are multiple layers of platforms on the steel frame, there are furnace walls on the inboard of the steel frame, including boiler drum, water-cooled wall, furnace wall, riser, downcomer, inlet flue, outlet flue and ash bucket, characterized by that, the boiler drum locates at the top end of the furnace body, the said water-cooled wall is the structure of the full membrane wall, the furnace chamber is divided into inlet area and outlet area by the water-cooled wall set up vertically in the furnace body, form the U-shaped flow path that the inlet area communicates with bottom of the outlet area; the top of the inlet area is provided with an inlet flue, the top of the outlet area is provided with an outlet flue, and the bottoms of the inlet area and the outlet area are respectively provided with an ash hopper; a plurality of denitration device mounting holes are arranged in a region of 1050 ℃ in the 900-plus-one region of the hearth inlet region, the denitration device mounting holes are distributed in an array mode, and the denitration device mounting holes are connected with denitration devices through pipelines.

The inlet flue is horizontally opened, the outlet flue is vertically opened, and the highest point elevation of the inlet flue with the same caliber as the outlet flue is lower than the outlet flue by 250-450 mm.

The full-membrane water-cooled wall is formed by welding and connecting steel pipes and flat steel, and no gap exists between every two adjacent steel pipes.

The side wall of the ash bucket forms an included angle of 17.5-30 degrees with the vertical line.

The cross sections of the inlet area and the outlet area are both rectangular, and the ratio of the cross sections of the inlet area and the outlet area is 1.2-1.6: 1.

The denitration device is SNCR denitration equipment.

The ascending pipe is provided with a 90-degree corner formed by connecting a vertical section and a horizontal section before being connected with the boiler barrel.

And a composite heat-insulating layer consisting of an aluminum silicate refractory fiber layer and an outer guard plate is arranged on the outer side of the water-cooled wall, the thickness of the composite heat-insulating layer is 150-350mm, and the thickness of the aluminum silicate refractory fiber layer is not less than 120 mm.

The inlet area and the outlet area are provided with a plurality of soot blowing observation holes from top to bottom, and the soot blowing observation holes are provided with matching structures matched with the shock wave soot blowers or the elastic vibrators.

Compared with the prior art, the invention has the beneficial effects that: 1) the boiler adopts a vertical arrangement form and a U-shaped flue structure, the outlet flue outlet is higher than the inlet flue inlet, and the section of the outlet area is smaller than that of the inlet area, so that the flow rate of flue gas is stable, and the effective utilization rate of flue gas heat is improved by 15%. 2) The whole hearth is formed by the full-film type wall structure for the boiler, the whole structure is simple, the occupied area is small, the sealing effect is good, the air leakage loss can be reduced, and the heat insulation of the outer side of the film type wall is realized by adopting aluminum silicate refractory fiber and an outer guard plate, so that the heat dissipation loss can be reduced. 3) The inlet area and the outlet area are respectively provided with the ash hoppers, so that the sedimentation and collection of dust in the flue gas are facilitated, the resynthesis of decomposed dioxin-like substances is prevented, and the environmental protection requirement is met. 4) Denitration in the furnace is creatively realized, the denitration device is arranged in a temperature area with the flue gas temperature of 900-1050 ℃, and the denitration device is arranged on a water-cooled wall, so that denitration in the furnace can be realized at 70-110% of rated load, and the environmental protection requirement is met.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a schematic view of a furnace configuration in an embodiment of the invention with a full film wall dividing the furnace into an inlet zone and an outlet zone;

FIG. 3 is a schematic view of the arrangement of mounting holes of a denitration apparatus according to an embodiment of the present invention;

FIG. 4 is a schematic view of a hazardous waste incineration system to which an embodiment of the present invention is applied.

In the figure: 1-boiler barrel, 2-water wall, 3-steel frame, 4-platform, 5-furnace wall, 6-outer protecting plate, 7-ascending pipe, 8-descending pipe, 9-inlet flue, 10-outlet flue, 11-ash bucket, 12-denitration equipment mounting hole, 13-ash blowing observation hole and 14-aluminum silicate refractory fiber layer.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, which are schematic structural views of an embodiment of the hazardous waste incineration tail gas waste heat boiler of the present invention, a boiler body is of a vertical structure and is vertically arranged in a steel frame 3, the steel frame 3 is provided with a multi-layer platform 4, the inner side of the steel frame 3 is provided with a furnace wall 5, the boiler body comprises a boiler barrel 1, a water wall 2, the furnace wall 5, an ascending pipe 7, a descending pipe 8, an inlet flue 9, an outlet flue 10 and an ash bucket 11, the boiler barrel 1 is located at the topmost end of the boiler body, the water wall 2 is of a full-film wall structure, a hearth in the boiler body is divided into an inlet area a and an outlet area B by the vertically arranged water wall 2, and a U-shaped flow channel is formed, wherein the inlet area a is communicated with the bottom of the outlet area B; the top of the inlet area A is provided with an inlet flue 9, the top of the outlet area B is provided with an outlet flue 10, the bottoms of the inlet area A and the outlet area B are respectively provided with an ash bucket 11, and the included angle between the side wall of the ash bucket 11 and a vertical line is 17.5-30 degrees, so that the sedimentation and collection of dust in the flue gas are facilitated.

The cross sections of the inlet area A and the outlet area B are both rectangular, and the ratio of the cross sections of the inlet area A and the outlet area B is 1.3: 1. A plurality of denitration device mounting holes 12 are arranged in a region of 1050 ℃ in the 900-plus-one region of a hearth inlet area A, the denitration device mounting holes 12 are distributed in an array mode, the denitration device mounting holes 12 are connected with denitration devices through pipelines, and the denitration device is SNCR denitration devices and well achieves denitration in a furnace. The inlet area A and the outlet area B are provided with a plurality of soot blowing observation holes 13 from top to bottom, and the soot blowing observation holes 13 are provided with matching structures matched with the shock wave soot blower or the elastic vibrator.

The inlet flue 9 is horizontally opened, the outlet flue 10 is vertically opened, and the highest point elevation of the inlet flue 9 with the same caliber as the outlet flue 10 is lower than that of the outlet flue 10 by about 250-450 mm. The ascending pipe 7 is provided with a 90-degree corner formed by connecting a vertical section and a horizontal section before being connected with the boiler barrel 1.

The full-membrane water-cooled wall 2 is formed by welding steel pipes and flat steel, finally encloses into a whole hearth, has no gap between adjacent steel pipes, has good sealing effect and can reduce air leakage loss. The composite heat-insulating layer consisting of the aluminum silicate fire-resistant fiber layer 14 and the outer guard plate 6 is arranged on the outer side of the water-cooled wall 2, the thickness of the composite heat-insulating layer is 150-350mm, the thickness of the aluminum silicate fire-resistant fiber layer is not less than 120mm, heat dissipation loss can be reduced, the whole structure is simple, and the occupied area is small.

When the embodiment of the invention is used in a hazardous waste incineration system, solid waste (solid waste) is sent into a solid waste storage bin after being pretreated, the solid waste is mixed and combusted with the auxiliary fuel oil and the waste liquid in the rotary kiln, the solid waste is further completely combusted with the auxiliary fuel oil and the waste liquid in the secondary chamber, slag is discharged, high-temperature flue gas sequentially enters a waste heat boiler, a quench tower, a dry deacidification tower, a bag-type dust remover and a washing tower, the dry deacidification tower can collect and discharge large-particle ash residues in the flue gas, the bag-type dust remover further collects and discharges small-particle fly ash, less-particle ash is collected by the washing tower, and the clean flue gas heater heats and discharges the ash. The waste heat boiler carries out heat recovery, and the flue gas is discharged outside after passing through a purification system of quenching, deacidification, dust removal, washing and reheating. The temperature of the discharged flue gas is above 160 ℃, and the concentration of nitrogen oxides after modification is less than 10 mg/cubic meter.

High-temperature flue gas with the temperature of over 1000 ℃ discharged from a second combustion chamber is input into an inlet area A of a hearth through an inlet flue 9, the high-temperature flue gas flows from top to bottom in the inlet area A and enters an outlet area B from the bottom, the high-temperature flue gas releases heat while falling in the inlet area A, along with the change of flow velocity, smoke dust mixed in the high-temperature flue gas drifts down into an ash bucket, the high-temperature flue gas without the smoke dust continuously releases heat in the outlet area B and is then discharged from the outlet flue, and the temperature of the high-temperature flue gas after releasing heat for multiple times when being discharged from the outlet flue is not more than 250 ℃, so that the requirement of subsequent further dust removal and discharge is met;

medium water in the water-cooled wall 2 exchanges heat with high-temperature flue gas in the furnace body, the medium water is heated into steam-water mixtures through the heat exchange medium water, the steam-water mixtures rise to the upper parts of the shells and return to the drum 1 through the ascending pipes 7, the steam-water mixtures are separated into steam and condensed water through a steam-water separator in the drum, the steam is output from a steam conveying port at the top of the drum to a pipe network for use, and the condensed water is output from the descending pipes 8 after being heated to continuously participate in the circulation process.

The invention adopts the vertical boiler and the U-shaped flue structure, thus having small resistance, simple structure, convenient manufacture and convenient cleaning when scaling in the pipe; the boiler can be supported by a converter platform; the device is suitable for recovering heat energy in the flue gas in a hazardous waste incineration system, and reduces heat energy loss.

The denitration reactor in the boiler solves the problems of narrow site, constant heat calculation and the like of the prior boiler, and is difficult to install in front of an air preheater or an economizer. The 900-1050 ℃ region of the inlet region A provides enough reaction temperature for the denitration device, so that the window temperature required by the reaction can be reached, the high catalytic activity and the high conversion rate are maintained, the defects of the conventional denitration process at the position where the chimney is discharged are effectively overcome, the nitrogen oxide is removed in advance, the reaction chance of nitrogen oxide and ash in the flue gas can be reduced, and the resynthesis of decomposed dioxin-like substances is avoided.

After the method is implemented, denitration in the furnace can be realized at 70-110% of rated load, the environmental protection requirement is met, and the effects of energy conservation and emission reduction are obvious. Taking an example of a hazardous waste incineration system with an annual treatment capacity of 100 ten thousand tons, the emission of nitrogen oxides is reduced by about 1460 tons every year.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, and any person skilled in the art can substitute or change the technical solution of the present invention and its inventive concept within the technical scope of the present invention.