CN107062240A - The system and method for Thermal generation unit cooperated with consumer waste pyrolysis - Google Patents

Abstract

The invention discloses a system and method for coal-fired power generation unit cooperative domestic waste pyrolysis, which extracts part of the high-temperature flue gas generated by the boiler of the coal-fired power generation unit and directly sends it to a pyrolysis device to pyrolyze the domestic waste inside it. The final gas is introduced into the area where the burner is located in the boiler of the coal-fired generating set or its upper part to assist the combustion of coal and realize stable combustion or recombustion. The present invention directly utilizes the existing equipment of the coal-fired unit, organically combines the excess production capacity with the resource utilization of household garbage, reduces the investment cost of garbage treatment, and simultaneously solves the problem of low-load stable combustion and combustion transformation investment of the coal-fired power plant, and realizes the maximization of benefits.

Description

System and method for coordinating domestic waste pyrolysis with coal-fired power generation units

technical field

The invention relates to a system and method for coal-fired generating sets to cooperate with domestic waste pyrolysis.

Background technique

With the rapid development of the economy and the continuous deepening of the urbanization process, the output of domestic waste continues to increase. Domestic waste occupies the soil, pollutes the environment, and has a negative impact on people's health. The use of incineration of household waste to generate electricity has become a very common treatment method. Some provinces and autonomous regions have also issued the "Opinions on Further Strengthening the Incineration and Treatment of Municipal Domestic Waste", requiring that in principle, all domestic waste should be treated with incineration (power generation) treatment technology.

However, the processing capacity of existing domestic waste incineration plants is insufficient. According to opinions, a large number of incineration plants need to be built in various places, which requires huge investment and complicated construction. The current domestic waste treatment methods are all to crush, sort, dry, and then send the domestic waste to a special waste incinerator for combustion. The above-mentioned technologies all have the following problems:

(1) A large amount of dioxin is produced, and dioxin in the environment is difficult to degrade and eliminate naturally, and has strong toxicity. According to a survey, the dioxin content in the blood of waste incineration workers is 806pgTEQ/L, which is normal It is about 40 times the level of the population; Dioxin discharged into the atmosphere can be adsorbed on particulate matter, settle to water and soil, and then enter the human body through the enrichment of the food chain, endangering people's health and the environment;

(2) A large amount of other pollutants such as NO _X are produced, which will pollute the environment, and the pollutant treatment equipment of the incineration plant has a large investment and high input cost;

(3) To build a large-scale incineration plant, boilers and supporting systems need to be invested, which requires high input costs, occupies a large amount of urban or urban land, and requires a large investment.

At the same time, with the slowdown of my country's economic growth and insufficient electricity consumption, coal-fired power plants have overcapacity, and the utilization hours and equipment utilization of generating units continue to decline. How to improve the equipment utilization rate and improve the economic and social benefits of the power plant is undoubtedly of great significance. At the same time, due to the decline in unit utilization hours, boilers in coal-fired power plants often operate at low loads, and boilers tend to burn unstable under low loads. How to ensure the stable combustion of the boiler is also an important problem to be solved urgently. In addition, the pollutant treatment system of the coal-fired power plant itself is very complete and efficient. Due to the low-load operation of the unit, its utilization rate is insufficient, and it is difficult to exert the best benefits.

If a domestic waste gasification device is built in an existing coal-fired power plant, the high-temperature flue gas generated by the power plant boiler is used to gasify domestic waste, which not only effectively utilizes the waste heat of the high-temperature flue gas generated by the power plant, improves the use efficiency of power plant equipment, but also saves It eliminates the heat source and energy consumption of conventional domestic waste incineration plants (often need to burn coal) and the huge cost of new pollutant treatment systems. In addition, the gas produced by gasification can be returned to the boiler for combustion to achieve stable combustion, while taking into account the reduction of NO _X , which is also of great benefit to the normal operation of the boiler at low load. Therefore, the coal-fired power generation unit coordinated with the gasification of domestic waste has multiple benefits and serves multiple purposes. Domestic waste incineration power generation can be combined with coal-fired power plant units.

Contents of the invention

In order to solve the above problems, the present invention proposes a system and method for coordinating domestic waste pyrolysis with coal-fired generator sets. The present invention directly utilizes the existing boiler equipment in coal-fired power plants, and introduces the high-temperature flue gas generated by the boiler as a heat source into pyrolysis The device is used for pyrolysis of domestic waste, and then the pyrolyzed gas is sent to the boiler for high-temperature incineration, which inhibits the precipitation of dioxins from the source, not only handles domestic waste, but also solves the problem of low-load stable combustion of the boiler.

In order to achieve the above object, the present invention adopts the following technical solutions:

A coal-fired generator unit cooperative domestic waste pyrolysis system, extracting part of the high-temperature flue gas generated by the boiler of the coal-fired power unit and directly sending it to the pyrolysis device to pyrolyze the domestic waste inside, and the pyrolyzed gas is introduced into the coal-fired waste The area where the burner in the generator set boiler is located assists coal combustion to achieve stable combustion. By introducing gas into the burner section, stable combustion can be achieved, which solves the problem of stable combustion at low load of the boiler.

Further, the gas is introduced into the upper part of the boiler furnace through a high-temperature gas fan, and a staged combustion method is adopted to suppress the formation of NOx in the furnace, so as to realize low NOx emission of the coal-fired power plant boiler.

Further, the gasification device is a pyrolysis furnace.

Further, the gasification device includes a drying device for drying domestic waste.

Household garbage has been sorted, crushed and dried in advance.

A coal-fired generator unit cooperative domestic waste pyrolysis system, extracting part of the high-temperature flue gas generated by the boiler of the coal-fired power unit and directly sending it to the pyrolysis device to pyrolyze the domestic waste inside, and the pyrolyzed gas is introduced into the coal-fired waste The upper part of the area where the burner is located in the boiler of the generator set, for reburning. Reburning can help denitrification, reduce the emission of nitrogen oxides, and achieve energy saving and environmental protection.

A method for coordinating domestic waste pyrolysis with coal-fired power generation units. Part of the high-temperature flue gas generated by the boiler of the coal-fired power generation unit is directly sent to the pyrolysis device to pyrolyze the domestic waste inside it, and the gas generated by the pyrolysis is introduced into the boiler In the area where the burner is located, it assists coal combustion to achieve stable combustion and solve the problem of low-load stable combustion.

A method for coordinating domestic waste pyrolysis with coal-fired power generation units, sending part of the high-temperature flue gas generated by the boiler of the coal-fired power generation unit into the pyrolysis device to pyrolyze the domestic waste inside it, and introducing the gas generated by the pyrolysis into the boiler The upper end of the area where the burner is located is reburned.

The temperature of the high-temperature flue gas is 600-1000°C.

The amount of high-temperature flue gas introduced is confirmed and adjusted according to its temperature.

Compared with prior art, the beneficial effect of the present invention is:

(1) The present invention uses the high-temperature flue gas generated by the combustion of existing boiler equipment in coal-fired power plants as a heat source for the pyrolysis of domestic waste, and then sends the gas produced by pyrolysis into the above-mentioned boiler equipment for combustion, without the need to establish multiple An incinerator can efficiently and cost-effectively dispose domestic waste as a resource, filling the technical gap at home and abroad;

(2) The present invention combines the treatment of domestic waste with the reutilization of excess resources of coal-fired power generating units, and can use a small amount of boiler high-temperature flue gas heat, thereby slightly reducing the power generation capacity and hours of power generation of the power plant, which is different from the current The plant conditions match.

(3) In terms of equipment cost investment, it only needs to add an additional pyrolysis furnace, without large-scale equipment transformation and research and development. Through the gas return boiler, the problem of stable combustion under low load of coal-fired power plants is solved, and the maximum benefit is achieved. change;

(4) Using the gas back injection boiler produced by waste pyrolysis to implement staged combustion will help reduce the emission of tar, NO _X and other pollutants, making the boiler more environmentally friendly. In addition, there is no need to build a separate waste incineration pollution treatment system, and the existing pollutant treatment system of the power plant itself can be used, which improves the utilization efficiency of the equipment and greatly reduces the overall cost.

(5) The traditional waste incineration power generation technology is carried out in an oxidizing atmosphere, and the generation of dioxin is unavoidable. However, in the process of waste pyrolysis and incineration, oxygen is isolated, and the conditional factors for the formation of dioxins are basically eliminated, thereby largely avoiding the generation of dioxins at the source of waste incineration. Even if a small amount of dioxin is produced during the pyrolysis process, it can be decomposed by high-temperature combustion in the boiler, ensuring the complete decomposition and combustion of toxic organic gases such as dioxin at high temperature.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide further understanding of the present application, and the schematic embodiments and descriptions of the present application are used to explain the present application, and do not constitute improper limitations to the present application.

Fig. 1 is the structural representation of the first embodiment of the present invention;

Fig. 2 is the structural representation of the second embodiment of the present invention;

Among them: 1. Drying device, 2. Pyrolysis furnace, 3. High temperature gas fan, 4. Combustion boiler, 5. Burner, 6. Steam turbine, 7. Generator, 8. Air preheater, 9. High temperature flue gas , 10, ash, 11, exhaust gas, 12, gas after pyrolysis, 13, treated domestic waste, 14, flue.

detailed description:

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

It should be pointed out that the following detailed description is exemplary and intended to provide further explanation to the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It should be noted that the terminology used here is only for describing specific implementations, and is not intended to limit the exemplary implementations according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and it should also be understood that when the terms "comprising" and/or "comprising" are used in this specification, they mean There are features, steps, operations, means, components and/or combinations thereof.

As introduced in the background technology, the domestic waste combustion technologies in the prior art all have the disadvantages of being unable to remove dioxins from the source, huge investment costs, and relatively large building renovations. In order to solve the above technical problems, this application proposes A system and method for coordinating domestic waste pyrolysis with coal-fired power generating units.

In a typical implementation of the present application, as shown in Figure 1, a coal-fired power unit cooperative domestic waste pyrolysis system is provided, and part of the high-temperature flue gas generated by the coal-fired power unit boiler is directly sent to the pyrolysis device for The internal domestic waste is pyrolyzed, and the pyrolyzed gas is introduced into the area where the burner is located in the boiler of the coal-fired generating set to assist coal combustion and achieve stable combustion. By introducing gas into the burner section, stable combustion can be achieved, which solves the problem of stable combustion at low load of the boiler.

The flue in the boiler leads into a bypass to send high-temperature flue gas into the pyrolysis device, and a control valve is set on the bypass to control the delivery of flue gas.

At the same time, an air preheater is installed in the flue, and the flue gas is discharged after passing through the air preheater.

The gas is introduced into the boiler through a high-temperature gas fan.

The pyrolysis device is a pyrolysis furnace.

The pyrolysis unit includes lifting devices that feed domestic waste into its treatment area.

Household garbage has been sorted, crushed and dried in advance.

The steam generated after reburning is sent to the steam turbine for power generation through the original equipment of the coal-fired power plant.

A method for coal-fired generating set cooperating with domestic waste pyrolysis, in which part of the high-temperature flue gas generated by the boiler of the coal-fired generating set is directly sent to the pyrolysis device to pyrolyze the domestic waste inside it, and the gas generated by the pyrolysis is introduced into the boiler The area where the burner is located assists coal combustion to achieve stable combustion and solve the problem of low-load stable combustion.

The temperature of the high-temperature flue gas is 600-1000°C.

The amount of high-temperature flue gas introduced is confirmed and adjusted according to its temperature.

The pyrolysis unit has a slagging component.

Among them, the pyrolysis device, air preheater, high-temperature gas blower, etc. can use existing devices.

As shown in Figure 2, the second typical implementation of the present invention provides a coal-fired power unit cooperative domestic waste pyrolysis system, and part of the high-temperature flue gas generated by the coal-fired power unit boiler is directly sent to the interior of the pyrolysis device The domestic waste is pyrolyzed, and the pyrolyzed gas is introduced into the upper part of the area where the burner is located in the boiler of the coal-fired generating set for stable combustion.

At the same time, it provides a coal-fired power generation unit cooperative domestic waste pyrolysis method, which sends part of the high-temperature flue gas generated by the coal-fired power unit boiler directly into the pyrolysis device to pyrolyze the domestic waste inside, and the gas generated by the pyrolysis Introduced into the upper part of the burner area in the boiler for reburning. Reburning can help denitrification, reduce the emission of nitrogen oxides, and achieve energy saving and environmental protection.

The temperature of the high-temperature flue gas is 600-1000°C.

The amount of high-temperature flue gas introduced is confirmed and adjusted according to its temperature.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, those skilled in the art do not need to pay creative work Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (10)

1. A coal-fired generating unit cooperative domestic waste pyrolysis system, characterized in that: part of the high-temperature flue gas produced by the coal-fired generating unit boiler is directly sent to the pyrolysis device to pyrolyze the domestic waste inside, and the pyrolyzed The gas is introduced into the area where the burner is located in the boiler of the coal-fired generating set to assist the combustion of coal and achieve stable combustion. 2. A system for coal-fired generator set cooperating with domestic waste pyrolysis as claimed in claim 1, characterized in that: the gas is introduced into the boiler through a high-temperature gas blower. 3. A coal-fired generating unit cooperative domestic waste pyrolysis system as claimed in claim 1, characterized in that: the pyrolysis device is a pyrolysis furnace. 4. A coal-fired power unit cooperative domestic waste pyrolysis system as claimed in claim 1, characterized in that: said gasification device includes a drying device for drying domestic waste. 5. A coal-fired generating unit cooperative domestic waste pyrolysis system, characterized in that: part of the high-temperature flue gas generated by the coal-fired generating unit boiler is directly sent to the pyrolysis device to pyrolyze the domestic waste inside, and the pyrolyzed The gas is introduced into the upper part of the area where the burner is located in the boiler of the coal-fired generating set for reburning. 6. A coal-fired generating set cooperative domestic waste pyrolysis method, characterized in that: part of the high-temperature flue gas produced by the coal-fired generating set boiler is directly sent to the pyrolysis device to pyrolyze the domestic waste inside, and the pyrolyzed The generated gas is introduced into the area where the burner is located in the boiler to assist coal combustion to achieve stable combustion and solve the problem of low-load stable combustion. 7. A coal-fired generating unit collaborative domestic waste pyrolysis method, characterized in that: part of the high-temperature flue gas produced by the coal-fired generating unit boiler is directly sent to the pyrolysis device to pyrolyze the domestic waste inside, and the pyrolyzed The generated gas is introduced into the upper part of the boiler where the burner is located for reburning to achieve low NOx emissions from the boiler. 8. A coal-fired power generation unit cooperative domestic waste pyrolysis method according to claim 6 or 7, characterized in that: the temperature of the high-temperature flue gas is 600-1000°C. 9. A coal-fired power generation unit cooperative domestic waste pyrolysis method as claimed in claim 6 or 7, characterized in that: the amount of high-temperature flue gas introduced is confirmed and adjusted according to its temperature. 10. A method for coal-fired power generation unit synergistic domestic waste pyrolysis as claimed in claim 6 or 7, characterized in that the domestic waste is pre-treated by sorting, crushing and drying.