CN112762456A

CN112762456A - Coupling system and coupling method for garbage pyrolysis gasification and coal-fired boiler power generation

Info

Publication number: CN112762456A
Application number: CN202110087254.1A
Authority: CN
Inventors: 罗传奎; 胡俊杰; 熊天柱; 周昀; 李涛
Original assignee: Shanghai Nenghui Technology Co ltd
Current assignee: Shanghai Nenghui Technology Co ltd
Priority date: 2021-01-22
Filing date: 2021-01-22
Publication date: 2021-05-07

Abstract

The invention provides a coupling system and coupling method of waste pyrolysis gasification and coal-fired boiler power generation. The coupling system of waste pyrolysis gasification and coal-fired boiler power generation includes waste pretreatment system, waste pyrolysis system, coal-fired boiler flue gas treatment system and coal-fired unit low-pressure water supply system. After adopting the technical solution of the present application, the waste pyrolysis process and the coal-fired boiler power generation process are coupled with each other, wherein the waste pyrolysis can share the existing flue gas treatment system of the coal-fired boiler, thereby reducing the equipment cost of waste pyrolysis, while the combustion Coal boiler power generation can also utilize the waste heat in the process of waste pyrolysis to further improve the heating efficiency of low-pressure feed water. The system provided by the invention has less investment and quick effect, and has great economic and social benefits.

Description

Coupling system and coupling method for garbage pyrolysis gasification and coal-fired boiler power generation

Technical Field

The invention relates to the technical field of garbage treatment and utilization, in particular to a coupling system and a coupling method for garbage pyrolysis gasification and coal-fired boiler power generation.

Background

In recent years, with the development of the Chinese society, the urbanization process and the new rural construction pace are increasingly accelerated, the population in cities and towns is more and more developed towards intensive living, and the pollution of domestic garbage generated in daily life to the living environment is serious. The existing domestic garbage treatment modes mainly comprise the following four modes: landfill, composting, direct incineration, pyrolysis and gasification.

The landfill and composting method has the defects of large occupied area and easy secondary pollution of soil, underground water and the like. The direct incineration treatment of the garbage can achieve the purposes of volume reduction, weight reduction and harmless treatment, and can utilize the heat generated in the incineration process as resources, but the auxiliary energy sources such as electric power, fuel oil and the like are required to be added during the combustion, so that the equipment investment is huge. The high-temperature pyrolysis mainly adopts an external heating type heating method, and has the characteristics of simple equipment and low investment.

However, the waste heat generated in the pyrolysis process of the existing garbage pyrolysis system is not effectively utilized, and the yield is low. And the flue gas that the pyrolysis produced need pass through flue gas processing apparatus such as dust removal, deacidification after reaching standard can only discharge into the atmosphere, increased equipment investment cost and running cost.

Disclosure of Invention

In order to overcome the technical defects that the waste heat generated in the pyrolysis process of the conventional garbage pyrolysis system is not effectively utilized, the yield is low, the flue gas generated by pyrolysis can be discharged into the atmosphere after reaching the standard through flue gas treatment devices such as a dust removal device and a deacidification device, and the equipment investment cost and the operation cost are increased, the invention provides a coupling system for garbage pyrolysis gasification and coal-fired boiler power generation, which comprises:

the garbage pretreatment system comprises a garbage pool, a grab bucket device and a garbage high-temperature dryer;

the waste pyrolysis system comprises a pyrolysis furnace, a secondary combustion chamber, a waste heat boiler (preferably, the waste heat boiler comprises a heat exchange tube bundle), a combustion fan and an air heater;

a coal-fired boiler flue gas treatment system;

a low-pressure water supply system of the coal-fired unit; and

the pipeline system comprises a deodorization pipeline, a first combustion air pipeline, a second combustion air pipeline, a garbage conveying pipeline, a pyrolysis gas pipeline, a high-temperature steam main pipeline, a first high-temperature steam pipeline, a second high-temperature steam pipeline, a third high-temperature steam pipeline, a low-temperature steam main pipeline, a first low-temperature steam pipeline, a second low-temperature steam pipeline, a high-temperature flue gas pipeline and a first flue gas pipeline;

grab bucket device is arranged in putting rubbish high temperature drying ware into with rubbish from the rubbish pond, the one end of deodorization pipeline is equipped with a plurality of inlet scoops, the other end is connected in air heater, air heater locates combustion fan's exit, through rubbish pipeline intercommunication between rubbish high temperature drying ware and the pyrolysis oven, through first combustion air pipeline intercommunication between air heater and the pyrolysis oven, through second combustion air pipeline intercommunication between air heater and the second combustion chamber, through pyrolysis gas pipeline intercommunication between pyrolysis oven and the second combustion chamber, the first high temperature steam pipeline that extends out from rubbish high temperature drying ware, the second high temperature steam pipeline that extends out from air heater and the third high temperature steam pipeline that extends out from coal fired unit low pressure water supply system gather to high temperature steam main pipe and connect in exhaust-heat boiler through high temperature steam main pipe, the first low temperature steam pipeline that extends out from rubbish high temperature drying ware and the second high temperature steam pipeline that extends out from air heater The low-temperature steam pipeline gathers to low-temperature steam main pipe and connects in exhaust-heat boiler through low-temperature steam main pipe, connects through high-temperature flue gas pipeline between second combustion chamber and the exhaust-heat boiler, and the first flue gas pipeline that extends out from exhaust-heat boiler connects in coal fired boiler flue gas processing system.

Furthermore, the grab bucket device comprises a grab bucket, a lifting mechanism, a running mechanism, a lifting rope and a guide rail, wherein the guide rail is transversely arranged above the garbage pool and the garbage high-temperature dryer, the running mechanism is used for driving the grab bucket to transport garbage from the garbage pool to the garbage high-temperature dryer through transverse sliding on the guide rail, and the lifting mechanism is used for controlling the height of the grab bucket at the longitudinal position through the lifting rope.

Furthermore, the air suction opening is provided with a filter screen.

Further, the air heater comprises a plate heat exchanger. Plate heat exchangers have the advantages over tubular heat exchangers: 1. the heat transfer coefficient is high, 2, the structure is simple, the weight is light, the heat exchange area is small, the price is low, and 3, the heat loss is small;

the disadvantages are that: 1. the working capacity is small, 2, the resistance is large, 3, the working pressure is not too large, the medium temperature is not too high, and the pressure is high and is easy to leak. Therefore, the air heater heats the air by using steam, the pressure of the air heater and the air heater is not large, and the amount of combustion-supporting air required by the pyrolysis system is small, so that the air heater is suitable for the plate heat exchanger from the economic point of view.

Further, the #6 low pressure heater comprises a tubular heat exchanger.

Further, the duct system further comprises a second flue gas duct, a total flue gas duct, a third flue gas duct, a fourth flue gas duct, a fifth flue gas duct, a sixth flue gas duct and a seventh flue gas duct, coal fired boiler flue gas processing system includes coal fired boiler, the air preheater, SCR denitration reactor, the dust remover, the draught fan, desulphurization unit and chimney, the first flue gas pipeline that extends out from exhaust-heat boiler and the second flue gas pipeline that extends out from coal fired boiler gather for total flue gas pipeline and connect in SCR denitration reactor through total flue gas pipeline, through third flue gas pipeline intercommunication between SCR denitration reactor and the air preheater, through fourth flue gas pipeline intercommunication between air preheater and the dust remover, through fifth flue gas pipeline intercommunication before dust remover and the draught fan, through sixth flue gas pipeline intercommunication between draught fan and the desulphurization unit, through seventh flue gas pipeline intercommunication between desulphurization unit and the chimney.

Further, the coal-fired unit low-pressure water supply system comprises a sixth-stage steam extraction pipeline of a steam turbine of the coal-fired unit, a #6 low-pressure heater and a low-pressure water supply pipeline, the third high-temperature steam pipeline is communicated with the sixth-stage steam extraction pipeline of the steam turbine of the coal-fired unit, and the sixth-stage steam extraction pipeline and the low-pressure water supply pipeline of the steam turbine of the coal-fired unit are respectively connected with the #6 low-pressure heater.

A second aspect of the present application provides a coupling method of pyrolysis gasification of garbage and power generation of a coal-fired boiler, comprising the steps of:

s1 pretreatment of garbage: performing deodorization treatment on the garbage through a deodorization pipeline, and performing high-temperature drying treatment on the garbage through a garbage high-temperature dryer;

s2 pyrolysis of garbage: the air in the deodorization pipeline is heated by an air heater, the air discharged from the air heater respectively enters a pyrolysis furnace and a secondary combustion chamber to serve as combustion-supporting air, the high-temperature combustion-supporting air is more favorable for pyrolysis gasification and complete combustion pyrolysis of garbage, the pyrolysis gas of the pyrolysis furnace is discharged from an outlet of the pyrolysis furnace and is introduced into the secondary combustion chamber to be fully combusted, the retention time of the flue gas in the secondary combustion chamber is not less than 2 seconds, the temperature of the high-temperature flue gas discharged from the outlet of the secondary combustion chamber reaches 900-1200 ℃ (preferably 1100 ℃), and the temperature of the high-temperature flue gas is reduced to 360-420 ℃ (preferably 380 ℃) after heat exchange of a waste heat boiler and then enters a flue gas treatment system of a coal-fired boiler; in the process that the temperature of the high-temperature flue gas is changed from 900-1200 ℃ to 360-420 ℃ in the waste heat boiler, heating the low-temperature steam discharged from the garbage high-temperature dryer and the low-temperature steam discharged from the air heater to saturated steam with the temperature of 190 ℃ and the pressure of 1.25MPa, and discharging the saturated steam from an outlet of the waste heat boiler;

s3 flue gas treatment: enabling the flue gas at the temperature of 360-420 ℃ to enter a flue gas treatment system of a coal-fired boiler, thereby sequentially removing nitric oxides in the flue gas, reducing the temperature of the flue gas to be below 200 ℃, capturing dust in the flue gas and removing acid gases and redundant water in the flue gas; and

s4 heating treatment of low-pressure feed water of coal-fired unit: saturated steam with the temperature of 190 ℃ and the pressure of 1.25MPa discharged from the outlet of the waste heat boiler enters a #6 low-pressure heater to heat a low-pressure water supply pipeline, so that the temperature of the water supply pipeline of the coal-fired unit is increased, the heat efficiency of the water supply pipeline is increased, and waste heat of garbage pyrolysis is effectively utilized.

Further, the coupling method of the garbage pyrolysis gasification and the coal-fired boiler power generation further comprises the following steps: and introducing saturated steam with the temperature of 190 ℃ and the pressure of 1.25MPa discharged from the outlet of the waste heat boiler into the high-temperature garbage dryer to heat steam in the high-temperature garbage dryer, and introducing saturated steam with the temperature of 190 ℃ and the pressure of 1.25MPa discharged from the outlet of the waste heat boiler into the air heater to heat combustion air in the air heater.

Further, step S1 includes the steps of: the method comprises the following steps that garbage is placed into a garbage high-temperature dryer through a grab bucket, an inlet of the garbage high-temperature dryer is closed, then saturated steam which is discharged from an outlet of a waste heat boiler and has the temperature of 190 ℃ and the pressure of 1.25MPa is introduced into the garbage high-temperature dryer to achieve high-temperature drying of the garbage, organic matters in the garbage can be converted into biological fibers and the pyrolysis efficiency of the garbage can be improved, and the dried low-temperature steam returns to the waste heat boiler again to be heated; the deodorization pipeline arranged above the garbage pool collects garbage smell escaping from the garbage pool and communicates air in the garbage smell to an air suction port of the combustion fan; and discharging the garbage dried at high temperature from the garbage high-temperature dryer and feeding the garbage into a pyrolysis furnace for pyrolysis and gasification.

After the technical scheme is adopted, compared with the prior art, the method has the following beneficial effects:

1. the utility model provides a coal fired boiler flue gas processing system among the effective utilization prior art of coupling system and coupling method of rubbish pyrolysis gasification and coal fired boiler electricity generation solves the flue gas treatment problem among the rubbish pyrolysis gasification process, the flue gas that the rubbish pyrolysis produced compares with the flue gas that coal fired boiler produced, only account for very little proportion, can not cause the influence to the original flue gas processing system of current coal fired boiler, need not to do any transformation to its equipment, also need not to set up special flue gas treatment facility for the rubbish pyrolysis, save area and investment cost.

2. The saturated steam temperature in exhaust-heat boiler export in this application is 190 ℃, pressure 1.25MPa, some is used for heating the required steam of rubbish pretreatment systems, some is arranged in air heater heating combustion-supporting air that the combustion-supporting fan was taken out, some steam and the sixth grade of steam extraction of coal-fired unit steam turbine in addition join and get into in the #6 low pressure water supply pipe of heating in the low pressure heater, improve coal-fired unit water supply pipe temperature promptly and increased its thermal efficiency, the waste heat of rubbish pyrolysis has effectively been utilized again, utilize the waste heat heating low pressure feedwater of city domestic waste pyrolysis process production, the thermal efficiency of coal-fired unit has further been improved.

3. Flue gas treatment pipeline and steam conduit among the pyrolysis gasification of rubbish are mutually independent, and the pyrolysis of rubbish process and coal fired boiler power generation process intercoupling, and wherein, thereby the pyrolysis of rubbish can utilize current coal fired boiler's flue gas processing system to reduce the flue gas treatment facility cost of pyrolysis of rubbish, and coal fired boiler power generation also can utilize the waste heat of pyrolysis of rubbish in-process, further improves the heating efficiency to the low pressure feedwater. The system provided by the invention has the advantages of low investment, quick response and great economic and social benefits.

Drawings

FIG. 1 is a schematic diagram of a coupling system for pyrolysis gasification of garbage and power generation of a coal-fired boiler and a coupling process thereof.

Reference numerals:

the system comprises a garbage pool 110, a grab bucket 121, a lifting mechanism 122, an operating mechanism 123, a lifting rope 124, a guide rail 125, a garbage high-temperature dryer 130, a pyrolysis furnace 210, a secondary combustion chamber 220, a waste heat boiler 230, a heat exchange tube bundle 231, a combustion fan 240, an air heater 250, a plate heat exchanger 251, a coal-fired boiler 310, an SCR denitration reactor 320, an air preheater 330, a dust remover 340, an induced draft fan 350, a desulphurization device 360, a chimney 370, a coal-fired unit turbine sixth-stage steam extraction pipeline 410, a #6 low-pressure heater 420, a tubular heat exchanger 421, a low-pressure water supply pipeline 430, a deodorization pipeline 501, an air suction inlet 502, a first combustion air pipeline 503, a second combustion air pipeline 504, a garbage conveying pipeline 505, a pyrolysis gas pipeline 506, a high-temperature steam main pipeline 507, a first high-temperature steam pipeline 508, a second high-temperature steam pipeline 509, a third high-temperature steam pipeline 510, a low-temperature steam main pipeline 511, a, A second low-temperature steam pipeline 513, a high-temperature flue gas pipeline 514, a first flue gas pipeline 515, a second flue gas pipeline 516, a total flue gas pipeline 517, a third flue gas pipeline 518, a fourth flue gas pipeline 519, a fifth flue gas pipeline 520, a sixth flue gas pipeline 521 and a seventh flue gas pipeline 522.

Detailed Description

The advantages of the invention are further illustrated in the following description of specific embodiments in conjunction with the accompanying drawings. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present disclosure. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

In the description of the present invention, unless otherwise specified and limited, it is to be noted that the terms "mounted," "connected," and "connected" are to be interpreted broadly, and may be, for example, a mechanical connection or an electrical connection, a communication between two elements, a direct connection, or an indirect connection via an intermediate medium, and specific meanings of the terms may be understood by those skilled in the art according to specific situations.

As shown in fig. 1, the present application provides a coupling system for pyrolysis gasification of garbage and power generation of a coal-fired boiler, comprising:

the garbage pretreatment system comprises a garbage pool 110, a grab bucket 121, a lifting mechanism 122, a running mechanism 123, a lifting rope 124 and a guide rail 125 (the guide rail 125 is transversely arranged above the garbage pool 110 and a garbage high-temperature dryer 130, the running mechanism is used for transversely sliding on the guide rail 125 so as to drive the grab bucket 121 to transport garbage from the garbage pool 110 to the garbage high-temperature dryer 130, and the lifting mechanism 122 is used for controlling the height of the grab bucket 121 in the longitudinal direction through the lifting rope 124), the garbage high-temperature dryer 130 and a deodorization pipeline 501; a waste pyrolysis system comprising a pyrolysis furnace 210, a secondary combustion chamber 220, a waste heat boiler 230 (preferably, the waste heat boiler 230 comprises a heat exchange tube bundle 231), a combustion fan 240 and an air heater 250; a coal-fired boiler flue gas treatment system; the low-pressure water supply system of the coal-fired unit comprises a sixth-stage steam extraction pipeline 410 of a steam turbine of the coal-fired unit, a #6 low-pressure heater 420 (a tubular heat exchanger 421 is arranged inside) and a low-pressure water supply pipeline 430, the third high-temperature steam pipeline 510 is communicated with the sixth-stage steam extraction pipeline 410 of the steam turbine of the coal-fired unit, and the sixth-stage steam extraction pipeline 410 and the low-pressure water supply pipeline 430 of the steam turbine of the coal-fired unit are respectively connected with the #6 low-pressure heater 420; and the pipeline system comprises a deodorization pipeline 501, a first combustion air pipeline 503, a second combustion air pipeline 504, a garbage conveying pipeline 505, a pyrolysis gas pipeline 506, a high-temperature steam main pipeline 507, a first high-temperature steam pipeline 508, a second high-temperature steam pipeline 509, a third high-temperature steam pipeline 510, a low-temperature steam main pipeline 511, a first low-temperature steam pipeline 512, a second low-temperature steam pipeline 513, a high-temperature flue gas pipeline 514, a warm flue gas pipeline 514, a second flue gas pipeline 516, a third flue gas pipeline 518, a fourth flue gas pipeline 519, a fifth flue gas pipeline 520, a sixth flue gas pipeline 521 and a seventh flue gas pipeline 522, the coal-fired boiler flue gas treatment system comprises a coal-fired boiler 310, an air preheater 330, an SCR denitration reactor 320, a dust remover 340, an induced draft fan 350, a desulfurization device 360 and a chimney 370, and the warm flue gas pipeline 514 extending from the waste heat boiler 230 and the second flue gas pipeline 516 extending from the coal-fired boiler 310 are gathered into a total flue gas pipeline 517 and pass through the total flue gas pipeline Flue gas pipeline 517 connects in SCR denitration reactor 320, communicate through third flue gas pipeline 518 between SCR denitration reactor 320 and the air preheater 330, communicate through fourth flue gas pipeline 519 between air preheater 330 and the dust remover 340, communicate through fifth flue gas pipeline 520 before dust remover 340 and draught fan 350, communicate through sixth flue gas pipeline 521 between draught fan 350 and the desulphurization unit 360, communicate through seventh flue gas pipeline 522 between desulphurization unit 360 and the chimney 370.

The grab bucket 121 is used for placing garbage into the garbage high-temperature dryer 130 from the garbage pool 110, one end of the deodorization pipeline 501 is provided with a plurality of air suction ports 502, preferably, the air suction ports 502 are provided with filter screens, the other end of the deodorization pipeline is connected to the air heater 250 (provided with a plate heat exchanger 251), the air heater 250 is arranged at the outlet of the combustion fan 240, the garbage high-temperature dryer 130 is communicated with the pyrolysis furnace 210 through a garbage conveying pipeline 505, the air heater 250 is communicated with the pyrolysis furnace 210 through a first combustion air pipeline 503, the air heater 250 is communicated with the second combustion chamber 220 through a second combustion air pipeline 504, the pyrolysis furnace 210 is communicated with the second combustion chamber 220 through a pyrolysis gas pipeline 506, a first high-temperature steam pipeline 508 extending from the garbage high-temperature dryer 130, a second high-temperature steam pipeline 509 extending from the air heater 250 and a third high-temperature steam pipeline 510 extending from a low-pressure water supply system of the unit are gathered into a high-temperature steam main The high-temperature steam main pipe 507 is connected to the waste heat boiler 230, a first low-temperature steam pipe 512 extending from the garbage high-temperature dryer 130 and a second low-temperature steam pipe 513 extending from the air heater 250 are gathered into a low-temperature steam main pipe 511 and connected to the waste heat boiler 230 through the low-temperature steam main pipe 511, the secondary combustion chamber 220 and the waste heat boiler 230 are connected through a high-temperature flue gas pipe 514, and the high-temperature flue gas pipe 514 extending from the waste heat boiler 230 is connected to a flue gas treatment system of the coal-fired boiler.

The grab bucket 121 puts the garbage into the garbage high-temperature dryer 130 from the garbage pool 110, closes the inlet of the garbage high-temperature dryer 130, then introduces the steam which is discharged from the outlet of the waste heat boiler 230 and has the temperature of 190 ℃ and the pressure of 1.25MPa into the garbage high-temperature dryer 130, and the dried low-temperature steam returns to the waste heat boiler 230 again for heating; a deodorization pipeline 501 arranged above the garbage pool 110 collects garbage smell escaping from the garbage pool 110 and communicates air in the garbage smell to an air suction opening 502 of the combustion fan 240; the garbage dried at high temperature is discharged from the garbage high-temperature dryer 130 and enters the pyrolysis furnace 210 to be pyrolyzed and gasified;

the air in the deodorization pipeline 501 is heated by the air heater 250, the air discharged from the air heater 250 respectively enters the pyrolysis furnace 210 and the secondary combustion chamber 220 to be used as combustion-supporting air, the pyrolysis gas of the pyrolysis furnace 210 is discharged from the outlet of the pyrolysis furnace 210 and is introduced into the secondary combustion chamber 220 to be sufficiently combusted, the retention time of the flue gas in the secondary combustion chamber 220 is not less than 2 seconds, the temperature of the high-temperature flue gas discharged from the outlet of the secondary combustion chamber 220 reaches 1100 ℃, the temperature of the high-temperature flue gas is reduced to 380 ℃ after heat exchange of the waste heat boiler 230 and the high-temperature flue gas enters a flue gas treatment system of the coal-fired boiler, so that the nitrogen oxides in the flue gas are sequentially removed, the temperature of the flue gas is reduced to be below 200 ℃, the dust in the flue gas is captured, and; the high-temperature flue gas heats the low-temperature steam discharged from the waste high-temperature dryer 130 and the low-temperature steam discharged from the air heater 250 to steam with the temperature of 190 ℃ and the pressure of 1.25MPa in the process of changing from 1100 ℃ to 380 ℃ in the waste heat boiler 230 and discharges the steam from the outlet of the waste heat boiler 230, a part of the steam with the temperature of 190 ℃ and the pressure of 1.25MPa discharged from the outlet of the waste heat boiler 230 enters the #6 low-pressure heater 420 to heat the low-pressure feed water, a part of the steam enters the waste high-temperature dryer 130 to heat the steam in the waste high-temperature dryer 130, and the rest of the steam enters the air heater 250 to heat the combustion air in the air heater 250.

According to the technical scheme, the flue gas treatment pipeline and the steam pipeline in the garbage pyrolysis gasification process are mutually independent, and the garbage pyrolysis process and the power generation process of the coal-fired boiler are mutually coupled, wherein the garbage pyrolysis can share the flue gas treatment system of the conventional coal-fired boiler, so that the equipment cost of the garbage pyrolysis is reduced, the power generation of the coal-fired boiler can also utilize the waste heat in the garbage pyrolysis process, and the heating efficiency of low-pressure water supply is further improved.

It should be noted that the embodiments of the present invention have been described in terms of preferred embodiments, and not by way of limitation, and that those skilled in the art can make modifications and variations of the embodiments described above without departing from the spirit of the invention.

Claims

1. a coupling system of waste pyrolysis gasification and coal-fired boiler power generation, is characterized in that, comprises:

A garbage pretreatment system, the garbage pretreatment system includes a garbage pool, a grab device and a garbage high temperature dryer;

A waste pyrolysis system, the waste pyrolysis system includes a pyrolysis furnace, a secondary combustion chamber, a waste heat boiler, a combustion-supporting fan and an air heater;

Coal-fired boiler flue gas treatment system;

Low pressure water supply systems for coal-fired units; and

A pipeline system, the pipeline system includes a deodorization pipeline, a first combustion-supporting air pipeline, a second combustion-supporting air pipeline, a garbage conveying pipeline, a pyrolysis gas pipeline, a high-temperature steam main pipeline, a first high-temperature steam pipeline, a second high-temperature steam pipeline, The third high temperature steam pipeline, the low temperature steam main pipeline, the first low temperature steam pipeline, the second low temperature steam pipeline, the high temperature flue gas pipeline, and the first flue gas pipeline;

The grab device is used to put the garbage from the garbage pond into the garbage high-temperature dryer. One end of the deodorizing pipe is provided with several air suction ports, and the other end is connected to the air heater. The air heater is located at the outlet of the combustion-supporting fan. The high-temperature dryer and the pyrolysis furnace are communicated through the garbage conveying pipeline, the air heater and the pyrolysis furnace are communicated through the first combustion-supporting air pipeline, and the air heater and the second combustion chamber are communicated through the second combustion-supporting air pipeline. The pyrolysis furnace and the second combustion chamber are communicated through a pyrolysis gas pipeline, a first high-temperature steam pipeline extending from the waste high-temperature dryer, a second high-temperature steam pipeline extending from the air heater, and a low-pressure water supply system of the coal-fired unit. The third high-temperature steam pipes coming out are aggregated into the high-temperature steam main pipes and connected to the waste heat boiler through the high-temperature steam main pipes, the first low-temperature steam pipes extending from the waste high-temperature dryer and the second low-temperature steam pipes extending from the air heaters. It is aggregated into a low-temperature steam main pipeline and connected to the waste heat boiler through the low-temperature steam main pipeline. The second combustion chamber and the waste heat boiler are connected through a high-temperature flue gas pipeline. The first flue gas pipeline extending from the waste heat boiler is connected to the coal-fired boiler flue gas. processing system.

2. The coupling system of waste pyrolysis gasification and coal-fired boiler power generation according to claim 1, wherein the grab device comprises a grab, a lifting mechanism, a running mechanism, a hanging rope and a guide rail, the guide rail is transverse It is arranged above the garbage pond and the garbage high temperature dryer. The running structure is used to slide laterally on the guide rails to drive the grab bucket to transport the garbage from the garbage pond to the garbage high temperature dryer. The lifting mechanism is used to control the grab bucket in the longitudinal direction through the hanging rope. position height.

3 . The coupling system of waste pyrolysis gasification and coal-fired boiler power generation according to claim 1 , wherein the air suction port is provided with a filter screen. 4 .

4. The coupling system of waste pyrolysis gasification and coal-fired boiler power generation according to claim 1, wherein the air heater comprises a plate heat exchanger.

5. The coupling system of waste pyrolysis gasification and coal-fired boiler power generation according to claim 1, wherein the pipeline system further comprises a second flue gas pipeline, a total flue gas pipeline, a third flue gas pipeline, The fourth flue gas pipeline, the fifth flue gas pipeline, the sixth flue gas pipeline and the seventh flue gas pipeline, the coal-fired boiler flue gas treatment system includes a coal-fired boiler, an air preheater, an SCR denitration reactor, a dust collector, The induced draft fan, desulfurization device and chimney, the first flue gas pipe extending from the waste heat boiler and the second flue gas pipe extending from the coal-fired boiler are aggregated into a total flue gas pipe and connected to the SCR denitration reactor through the total flue gas pipe , the SCR denitration reactor and the air preheater are connected through the third flue gas pipeline, the air preheater and the dust collector are connected through the fourth flue gas pipeline, and the dust collector and the induced draft fan are connected through the fifth flue gas pipeline. The fan and the desulfurization device are communicated through the sixth flue gas pipeline, and the desulfurization device and the chimney are communicated through the seventh flue gas pipeline.

6 . The coupling system of waste pyrolysis gasification and coal-fired boiler power generation according to claim 1 , wherein the low-pressure water supply system of the coal-fired unit comprises the sixth-stage steam extraction pipeline of the steam turbine of the coal-fired unit, the #6 low pressure The heater and the low-pressure water supply pipeline, the third high-temperature steam pipeline is connected with the sixth-stage steam extraction pipeline of the steam turbine of the coal-fired unit, and the sixth-stage steam extraction pipeline and the low-pressure water supply pipeline of the coal-fired unit steam turbine are respectively connected to the #6 low-pressure heater.

7. The coupling system of waste pyrolysis gasification and coal-fired boiler power generation according to claim 6, wherein the #6 low pressure heater comprises a tubular heat exchanger.

8. A coupling method for waste pyrolysis gasification and coal-fired boiler power generation, characterized in that the method comprises the steps of:

S1 Garbage pretreatment: deodorize garbage through deodorizing pipeline, and dry garbage at high temperature through garbage high temperature dryer;

S2 waste pyrolysis: the air in the deodorization pipeline is heated by the air heater, the air discharged from the air heater enters the pyrolysis furnace and the secondary combustion chamber respectively as combustion-supporting air, and the pyrolysis gas of the pyrolysis furnace passes through the pyrolysis furnace The temperature of the high-temperature flue gas discharged from the outlet of the secondary combustion chamber reaches 900-1200 °C, and the high-temperature flue gas is cooled to 360-420 °C after heat exchange in the waste heat boiler and enters the combustion chamber. Coal boiler flue gas treatment system; the high temperature flue gas is heated from 900 to 1200 °C to 360 to 420 °C in the waste heat boiler from the low-temperature steam discharged from the high-temperature waste dryer and the low-temperature steam discharged from the air heater. Saturated steam with a temperature of 190℃ and a pressure of 1.25MPa is discharged from the outlet of the waste heat boiler;

S3 flue gas treatment: flue gas at 360 to 420 °C enters the coal-fired boiler flue gas treatment system, thereby sequentially removing nitrogen oxides in the flue gas, reducing the flue gas temperature to below 200 °C, capturing dust in the flue gas and Removal of acid gases and excess moisture from flue gas; and

Heating treatment of low-pressure feedwater for S4 coal-fired unit: The saturated steam with a temperature of 190°C and a pressure of 1.25MPa discharged from the outlet of the waste heat boiler enters the #6 low-pressure heater to heat the low-pressure feedwater.

9 . The method for coupling waste pyrolysis gasification and coal-fired boiler power generation according to claim 8 , further comprising the step of: discharging saturated steam with a temperature of 190° C. and a pressure of 1.25 MPa from the outlet of the waste heat boiler. 10 . Pass into the high-temperature garbage dryer to heat the steam in the high-temperature garbage dryer, and the saturated steam with a temperature of 190°C and a pressure of 1.25MPa discharged from the outlet of the waste heat boiler is passed into the air heater to heat the combustion support in the air heater Air.

10. The method for coupling waste pyrolysis gasification and coal-fired boiler power generation according to claim 9, wherein step S1 comprises: the grab device puts the waste from the waste pool into the waste high-temperature dryer, and closes the waste The inlet of the high-temperature dryer, and then the saturated steam with a temperature of 190°C and a pressure of 1.25MPa discharged from the outlet of the waste heat boiler is passed into the high-temperature waste dryer, and the low-temperature steam after drying is returned to the waste heat boiler for heating; set at The deodorizing pipe above the garbage pond collects the odor of garbage escaping from the garbage pond and connects the air in it to the air suction port of the combustion-supporting fan; the garbage after high temperature drying is discharged from the high temperature garbage dryer and enters the pyrolysis furnace to pyrolyze the gas. change.