Double-section type household garbage pyrolysis incineration system

Abstract

The utility model discloses a double-section type household garbage pyrolysis incineration system. Comprising a hearth, a garbage feeding hopper arranged above the hearth, a first-stage fire grate arranged below the garbage feeding hopper on one side of the hearth, a second-stage fire grate and a third-stage fire grate arranged below the hearth, a propeller arranged between the garbage feeding hopper and the hearth, and a pyrolytic reaction mechanism arranged on the propeller, and the slag outlet is formed in one side of the third-stage fire grate. The hearth comprises a hearth chamber, a furnace flue gas inlet with a downward opening is formed in the hearth chamber, a vertical front wall is arranged on one side of the furnace flue gas inlet, a furnace arch obliquely downward is arranged on the other side of the furnace flue gas inlet, and a furnace flue gas outlet is formed in the side edge of the hearth chamber. The device has the effect of improving the pyrolytic reaction efficiency and the working efficiency.

Description

Technical Field

[0001] This utility model relates to the field of organic solid waste treatment, and in particular to a two-stage municipal solid waste pyrolysis incineration system for miniaturized municipal solid waste. Background Technology

[0002] The utility model patent application filed by the applicant on July 11, 2020, with patent number 202021355064.0, is entitled "An Organic Waste Incineration Pyrolysis System." The core principle of this system is a furnace design employing low-temperature pyrolysis combined with high-temperature incineration. The low-temperature pyrolysis chamber utilizes the principle of heat conduction, employing radiant heat from the high-temperature incineration furnace and convective heat transfer from the flue gas to heat the bottom shell of the pyrolysis auger. Heat transfer to the municipal solid waste within the pyrolysis chamber is achieved through heat conduction from the bottom shell of the auger, thus enabling the municipal solid waste to undergo a pyrolysis reaction within the pyrolysis chamber. However, in practical use, this patented technology has been found to have low heat conduction efficiency, resulting in low pyrolysis reaction efficiency. Furthermore, because this patented technology uses a chain grate, the incineration process of municipal solid waste is uneven, requiring frequent manual feeding. Utility Model Content

[0003] In view of the above problems, the purpose of this utility model is to provide a two-stage municipal solid waste pyrolysis incineration system that improves pyrolysis reaction efficiency and working efficiency.

[0004] To achieve the above objectives, this utility model provides a two-stage municipal solid waste pyrolysis incineration system, comprising a furnace, a waste feed hopper located above the furnace, a primary grate located below the waste feed hopper on one side of the furnace, a secondary grate and a tertiary grate located below the furnace, a propeller located between the waste feed hopper and the furnace, a pyrolysis reaction mechanism located on the propeller, and a slag outlet located on one side of the tertiary grate. The furnace includes a furnace chamber, a downward-opening flue gas inlet located on the furnace chamber, a vertical front wall on one side of the flue gas inlet and a downward-sloping furnace arch on the other side, and a flue gas outlet located on the side of the furnace chamber.

[0005] In some embodiments, the propulsion unit includes a housing located between the waste feed hopper and the furnace, a hopper on one side of the housing that communicates with the housing and guides the material onto the primary grate, and a first auger and a second auger sequentially arranged within the housing below the corresponding waste feed hopper position. A misaligned sealing valve is provided between the waste feed hopper and the housing.

[0006] In some embodiments, the pyrolysis reaction mechanism includes a flue gas outlet communicating with the furnace chamber on the bottom of the box opposite to the flue gas inlet, a pyrolysis flue gas outlet on one side of the propeller, a condensation tower communicating with the pyrolysis flue gas outlet on the outside of the propeller, a pyrolysis fan on the condensation tower, and a secondary air duct communicating with the pyrolysis fan on the end of the furnace arch.

[0007] In some embodiments, the condenser includes a container tank connected to the pyrolysis flue gas outlet and the pyrolysis blower, a heat exchanger connected to a water medium inside the container tank, and a spray head connected to an alkaline solution above the heat exchanger.

[0008] In some embodiments, the propeller includes a housing located between the waste feed hopper and the furnace, a hopper on one side of the housing that communicates with the housing and guides the material onto the primary grate, and a third auger and a chain guard sequentially arranged within the housing below the corresponding waste feed hopper position. A misaligned sealing valve is provided between the waste feed hopper and the housing.

[0009] In some embodiments, the bottom of the housing is provided with a sloping bottom that also serves as a front wall. The propeller includes a housing located between the waste feed hopper and the furnace, a hopper on one side of the housing that communicates with the housing and guides the material to fall onto the primary grate, a fourth auger located inside the housing below the corresponding waste feed hopper, and a fifth auger on the sloping bottom of the housing that forms an angle with the fourth auger. The pyrolysis reaction mechanism includes a flue gas outlet on the sloping bottom opposite the flue gas inlet that communicates with the furnace chamber, a pyrolysis flue gas outlet on one side of the propeller, a condenser tower outside the propeller that communicates with the pyrolysis flue gas outlet, a pyrolysis fan on the condenser tower, and a secondary air duct at the end of the furnace arch that communicates with the pyrolysis fan.

[0010] In some embodiments, a vertically downward partition wall is provided inside the furnace chamber. Thus, a front wall, a furnace arch, and a partition wall are arranged sequentially from front to back inside the furnace to guide the flow of high-temperature flue gas within the furnace.

[0011] In some embodiments, an ash discharge valve is provided at the base of the furnace arch. The aforementioned valve is used to discharge the accumulated ash from the flue gas settling above the furnace arch to the slag outlet at the end of the grate.

[0012] The beneficial effects of this utility model are improved pyrolysis reaction efficiency and working efficiency. To overcome the shortcomings of existing technology, improve equipment performance, and meet practical needs, a direct contact method with hot flue gas is introduced to heat the pyrolysis chamber, thereby improving pyrolysis reaction efficiency. The grate structure and other components have also been upgraded. Specific measures are as follows: First, a waste drying and pyrolysis auger is installed at the upper part of the incinerator. High-temperature flue gas from the furnace is introduced through flue gas vents to dry and pyrolyze municipal solid waste, increasing its calorific value and improving its combustion characteristics. The high-temperature flue gas introduced through the vents can directly contact the waste, significantly improving heat exchange efficiency compared to traditional heat conduction methods and enhancing adaptability to fluctuations in waste composition. Second, the grate adopts a mechanical reciprocating grate, divided into three stages, each with independent drive, allowing adjustment of the residence time of waste on each stage, with an inclination angle ≥15°. This grate provides good disturbance during the waste incineration process, ensuring thorough and uniform combustion and preventing problems such as localized coking and underburning. Third, through the pyrolysis of municipal solid waste, organic chlorine in the waste can be released as HCl (pyrolysis temperature 280-320℃). This thermal dechlorination of the waste, followed by dechlorination of the pyrolysis fuel gas before it is returned to the furnace, reduces the content of precursors for dioxin synthesis during waste incineration, effectively controlling the amount of dioxins generated in the flue gas. Fourth, the dechlorinated pyrolysis gas is sent to the high-temperature flue gas zone of the incinerator as secondary air for combustion. This not only provides better turbulence in the combustion field, promoting the complete combustion of combustible gases in the high-temperature flue gas, but also, because the pyrolysis gas contains reducing gases (H2, CH4, CO, etc.), it can effectively reduce NOx in the high-temperature flue gas during re-combustion in the high-temperature zone of the furnace, thereby reducing nitrogen oxide emissions. Fifth, the furnace is equipped with structures such as a furnace arch, front wall, and partition walls to guide the orderly flow of high-temperature flue gas, thereby achieving effects such as turbulence, heat transfer, and inertial separation of fly ash. Furthermore, a partition wall is installed in the upper part of the furnace within the furnace arch to deflect the flue gas, effectively separating fly ash carried in the flue gas and preventing it from entering subsequent waste heat recovery equipment and causing blockages. The fly ash can be discharged into the slag discharge port through the ash discharge valve at the root of the furnace arch. Sixth, the condenser tower adopts a structural design combining spray and tubular heat exchangers. Firstly, it avoids direct contact between circulating water and condensate and tar in the flue gas, reducing wastewater generation. Secondly, the use of alkaline spray not only neutralizes and deacidifies acidic gases in the pyrolysis gas but also washes away tar condensed on the inner wall of the heat exchange tubes, preventing blockages and enhancing heat transfer efficiency. Therefore, it achieves the effect of improving pyrolysis reaction efficiency and overall working efficiency. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0014] Figure 2This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0015] Figure 3 This is a schematic diagram of the structure of Embodiment 3 of this utility model. Detailed Implementation

[0016] The utility model will now be described in further detail with reference to the accompanying drawings.

[0017] Example 1

[0018] like Figure 1As shown, a two-stage municipal solid waste pyrolysis incineration system includes a furnace 01, a waste feed hopper 02 located above the furnace 01, a primary grate 03 located below the waste feed hopper 02 on one side of the furnace 01, a secondary grate 04 and a tertiary grate 05 located below the furnace 01, a propeller 06 located between the waste feed hopper 02 and the furnace 01, a pyrolysis reaction mechanism 07 located on the propeller 06, and a slag outlet 08 located on one side of the tertiary grate 05. The furnace 01 includes a furnace chamber 11, a downward-opening flue gas inlet 12 located on the furnace chamber 11, a vertical front wall 13 located on one side of the flue gas inlet 12, a downward-sloping furnace arch 14 located on the other side, and a flue gas outlet 15 located on the side of the furnace chamber 11. The propeller 06 includes a housing 61 located between the waste feed hopper 02 and the furnace 01, a hopper 62 on one side of the housing 61 communicating with the housing 61 and guiding the material to fall onto the primary grate 03, and a first spiral auger 63 and a second spiral auger 64 sequentially arranged in the housing 61 below the corresponding position of the waste feed hopper 02. A misaligned sealing valve 65 is provided between the waste feed hopper 02 and the housing 61. The pyrolysis reaction mechanism 07 includes a flue gas vent 71 on the bottom of the housing 61 opposite to the position of the flue gas inlet 12, communicating with the furnace chamber 11, a pyrolysis flue gas outlet 72 on one side of the propeller 06, a condenser tower 73 on the outside of the propeller 06 communicating with the pyrolysis flue gas outlet 72, a pyrolysis fan 74 on the condenser tower 73, and a secondary air duct 75 on the end of the furnace arch 14 communicating with the pyrolysis fan 74. The condenser tower 73 includes a container tank 731 connected to the pyrolysis flue gas outlet 72 and the pyrolysis blower 74, a heat exchanger 732 connected to a water medium inside the container tank 731, and a spray head 733 connected to an alkaline solution above the heat exchanger 732. The heat exchanger is a shell-and-tube heat exchanger. When the condenser tower 73 is in operation: the tower wall has circulating cooling water inlet and outlet; the pyrolysis flue gas passes through the heat exchange tubes, and the circulating water passes outside the heat exchange tubes, thereby achieving cooling of the pyrolysis flue gas and condensation of water vapor; the acidic gases in the cooled and condensed pyrolysis flue gas are neutralized by the alkaline solution sprayed from the spray head 733 connected to the alkaline solution at the top of the condenser tower 73, resulting in purified pyrolysis flue gas, which is then transported by the pyrolysis blower 74 to the secondary air duct 75 inside the furnace 01 to complete the high-temperature decomposition of combustible gases in the pyrolysis flue gas. A vertically downward partition wall 16 is installed inside the furnace chamber 11. Inside the furnace 01, a front wall 13, a furnace arch 14, and a partition wall 16 are arranged sequentially from front to back to guide the flow of high-temperature flue gas inside the furnace 01. An ash discharge valve 17 is installed at the base of the furnace arch 14, which is used to discharge the ash accumulated by the flue gas settling above the furnace arch 14 to the slag outlet 08 at the end of the grate.

[0019] Working principle:

[0020] Municipal solid waste enters the first spiral auger 63 and the second spiral auger 64 through the feed hopper and feed sealing device; a portion of the high-temperature flue gas generated by the high-temperature incineration of waste in the furnace 01 passes through the second spiral auger 64 and the first spiral auger 63 in sequence through the flue gas inlet; the municipal solid waste is continuously tumbled under the action of the spiral auger blades and completes heat exchange with the high-temperature flue gas, thereby realizing the drying and partial pyrolysis process of municipal solid waste; the pyrolysis flue gas generated by drying and pyrolysis mainly consists of water vapor, HCl, tar, and combustible gas components such as CO; the pyrolysis flue gas enters the cold furnace flue gas outlet 15 at the end of the first spiral auger 63. In condenser tower 73, heat exchange occurs between the pyrolysis flue gas and cooling circulating water through heat exchange tubes, reducing the temperature of the flue gas to below the saturation temperature. Water vapor and tar components in the flue gas are condensed and precipitated. The acidic gas component HCl in the flue gas undergoes an acid-base neutralization reaction with the alkaline solution sprayed from the alkaline solution spray head 733, and is carried to the bottom of condenser tower 73 along with the condensate and tar components and discharged. After cooling, condensation, neutralization, and deacidification, the pyrolysis flue gas is extracted from condenser tower 73 by pyrolysis blower 74 and transported to secondary air duct 75 within the incinerator 01. The moisture content of the municipal solid waste decreases after drying and pyrolysis. The increased lower heating value significantly improves combustion characteristics. Conveyed by the second spiral auger 64 to the three-stage stepped reciprocating grate furnace at the bottom of the furnace 01, the waste undergoes a vigorous oxidation reaction with the air supplied by the bottom air chamber. Simultaneously, the waste is conveyed backward stage by stage under the reciprocating action of the grate. After the organic components in the municipal solid waste are completely decomposed at high temperature during combustion, the remaining slag is discharged from the slag discharge port. The high-temperature flue gas generated by combustion on the grate flows forward under the action of the furnace arch 14, providing heat to the waste on the front grate through thermal radiation, promoting the drying, preheating, and ignition processes. When the flue gas reaches the furnace arch 14... Following the front end, the flue gas enters the furnace chamber 01 above the furnace arch 14 under the action of the front wall 13. A secondary air nozzle (a secondary air duct 75 traverses the furnace chamber 01, with several nozzles distributed along the duct) is installed at the front end of the furnace arch 14. Purified pyrolysis gas is injected here. Under the action of the secondary air, the high-temperature flue gas undergoes turbulence, complete combustion, and nitrogen oxide re-combustion denitrification processes, resulting in complete decomposition of the high-temperature flue gas and pyrolysis gas. Under the action of the partition wall 16 in the upper part of the furnace chamber 01, the high-temperature flue gas undergoes inertial separation of fly ash. Most of the fly ash is blocked and falls into the root of the furnace arch 14, and is discharged from the slag outlet under the action of the ash discharge valve 17. After passing through the partition wall 16, the high-temperature flue gas exits the furnace chamber 01 and enters subsequent flue gas waste heat recovery systems, purification systems, and other devices. The slag outlet is at the end of the grate. An ash discharge valve 17 is located at the root of the furnace arch 14. Ash in the flue gas is deposited at the root of the furnace arch 14 and periodically discharged through the ash discharge valve 17 into the slag outlet at the end of the lower grate.

[0021] Example 2

[0022] like Figure 2As shown, a two-stage municipal solid waste pyrolysis incineration system includes a furnace 01, a waste feed hopper 02 located above the furnace 01, a primary grate 03 located below the waste feed hopper 02 on one side of the furnace 01, a secondary grate 04 and a tertiary grate 05 located below the furnace 01, a propeller 06 located between the waste feed hopper 02 and the furnace 01, a pyrolysis reaction mechanism 07 located on the propeller 06, and a slag outlet 08 located on one side of the tertiary grate 05. The furnace 01 includes a furnace chamber 11, a downward-opening flue gas inlet 12 located on the furnace chamber 11, a vertical front wall 13 located on one side of the flue gas inlet 12, a downward-sloping furnace arch 14 located on the other side, and a flue gas outlet 15 located on the side of the furnace chamber 11.

[0023] The propeller 06 includes a housing 61 located between the waste feed hopper 02 and the furnace 01, a hopper 62 on one side of the housing 61 that communicates with the housing 61 and guides the material onto the primary grate 03, and a third spiral auger 66 and a chain guard 67 sequentially arranged inside the housing 61 below the corresponding position of the waste feed hopper 02. A misaligned sealing valve 65 is provided between the waste feed hopper 02 and the housing 61. The pyrolysis reaction mechanism 07 includes a smoke vent 71 on the bottom of the housing 61 opposite to the flue gas inlet 12 that communicates with the furnace chamber 11, a pyrolysis flue gas outlet 72 on one side of the propeller 06, a condenser tower 73 on the outside of the propeller 06 that communicates with the pyrolysis flue gas outlet 72, a pyrolysis fan 74 on the condenser tower 73, and a secondary air duct 75 on the end of the furnace arch 14 that communicates with the pyrolysis fan 74. The condenser tower 73 includes a container tank 731 connected to the pyrolysis flue gas outlet 72 and the pyrolysis blower 74, a heat exchanger 732 connected to a water medium inside the container tank 731, and a spray head 733 connected to an alkaline solution above the heat exchanger 732. A vertically downward partition wall 16 is installed inside the furnace chamber 11. From front to back, a front wall 13, a furnace arch 14, and a partition wall 16 are arranged inside the furnace chamber 01 to guide the flow of high-temperature flue gas within the furnace chamber 01. An ash discharge valve 17 is installed at the base of the furnace arch 14, which discharges the accumulated ash from the flue gas settling above the furnace arch 14 to the slag outlet 08 at the end of the grate.

[0024] Example 3

[0025] like Figure 3As shown, a two-stage municipal solid waste pyrolysis incineration system includes a furnace 01, a waste feed hopper 02 located above the furnace 01, a primary grate 03 located below the waste feed hopper 02 on one side of the furnace 01, a secondary grate 04 and a tertiary grate 05 located below the furnace 01, a propeller 06 located between the waste feed hopper 02 and the furnace 01, a pyrolysis reaction mechanism 07 located on the propeller 06, and a slag outlet 08 located on one side of the tertiary grate 05. The furnace 01 includes a furnace chamber 11, a downward-opening flue gas inlet 12 located on the furnace chamber 11, a vertical front wall located on one side of the flue gas inlet 12, a downward-sloping furnace arch 14 located on the other side, and a flue gas outlet 15 located on the side of the furnace chamber 11. The bottom of the aforementioned housing 61 is provided with a downward-sloping bottom 68 that also serves as a front wall. The propeller 06 includes a housing 61 located between the waste feed hopper 02 and the furnace 01; a hopper 62 located on one side of the housing 61, communicating with the housing 61 and guiding material onto the primary grate 03; a fourth auger 69 located within the housing 61 below the waste feed hopper 02; and a fifth auger 60 located on the sloping bottom 68 of the housing 61, forming an angle with the fourth auger 69. The pyrolysis reaction mechanism 07 includes a flue gas outlet 71 on the sloping bottom 68 opposite the flue gas inlet 12, communicating with the furnace chamber 11; a pyrolysis flue gas outlet 72 located on one side of the propeller 06; a condenser tower 73 located outside the propeller 06, communicating with the pyrolysis flue gas outlet 72; a pyrolysis fan 74 located on the condenser tower 73; and a secondary air duct 75 located at the end of the furnace arch 14, communicating with the pyrolysis fan 74. A vertically downward partition wall 16 is installed inside the furnace chamber 11. Inside the furnace 01, from front to back, there are a sloping bottom 68, a furnace arch 14, and a partition wall 16, which are used to guide the flow of high-temperature flue gas inside the furnace 01. An ash discharge valve 17 is installed at the base of the furnace arch, which is used to discharge the ash accumulated by the flue gas settling above the furnace arch to the slag outlet 08 at the end of the grate.

[0026] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. A two-stage household garbage pyrolysis incineration system, characterized in that, The furnace includes a furnace chamber, a garbage feeding hopper arranged above the furnace chamber, a first grate arranged below the garbage feeding hopper on one side of the furnace, a second grate and a third grate arranged below the furnace chamber, a pusher arranged between the garbage feeding hopper and the furnace, a pyrolysis reaction mechanism arranged on the pusher, and a slag outlet arranged on one side of the third grate. The furnace chamber includes an open downward flue gas inlet, a vertical front wall arranged on one side of the flue gas inlet, a downward inclined arch arranged on the other side of the flue gas inlet, and a flue gas outlet arranged on the side of the furnace chamber.

2. The two-stage household garbage pyrolysis incineration system according to claim 1, characterized in that, The pusher includes a box arranged between the garbage feeding hopper and the furnace, a bunker arranged on one side of the box and guiding the material to fall on the first grate, and a first screw auger and a second screw auger arranged in the box below the position corresponding to the garbage feeding hopper. A staggered sealing valve is arranged between the garbage feeding hopper and the box.

3. The two-stage household garbage pyrolysis incineration system according to claim 1, characterized in that, The pyrolysis reaction mechanism includes a smoke hole arranged on the bottom of the box opposite to the position of the flue gas inlet, a pyrolysis flue gas outlet arranged on one side of the pusher, a condensation tower arranged outside the pusher and communicating with the pyrolysis flue gas outlet, a pyrolysis fan arranged on the condensation tower, and a secondary air pipe arranged on the end of the arch and communicating with the pyrolysis fan.

4. The two-stage household garbage pyrolysis incineration system according to claim 3, characterized in that, The condensation tower includes a container tank communicating with the pyrolysis flue gas outlet and the pyrolysis fan, a heat exchanger arranged in the container tank and connected with a water medium, and a spray head arranged above the heat exchanger and connected with an alkali solution.

5. The two-stage household garbage pyrolysis incineration system according to claim 1, characterized in that, The pusher includes a box arranged between the garbage feeding hopper and the furnace, a bunker arranged on one side of the box and guiding the material to fall on the first grate, and a third screw auger and a chain guard arranged in the box below the position corresponding to the garbage feeding hopper. A staggered sealing valve is arranged between the garbage feeding hopper and the box.

6. The two-stage household garbage pyrolysis incineration system according to claim 2, characterized in that, The bottom of the box is provided with a downward inclined bottom serving as a front wall. The pusher includes a box arranged between the garbage feeding hopper and the furnace, a bunker arranged on one side of the box and guiding the material to fall on the first grate, a fourth screw auger arranged in the box below the position corresponding to the garbage feeding hopper, and a fifth screw auger arranged on the inclined bottom of the box and forming an angle with the fourth screw auger. The pyrolysis reaction mechanism includes a smoke hole arranged on the inclined bottom opposite to the position of the flue gas inlet, a pyrolysis flue gas outlet arranged on one side of the pusher, a condensation tower arranged outside the pusher and communicating with the pyrolysis flue gas outlet, a pyrolysis fan arranged on the condensation tower, and a secondary air pipe arranged on the end of the arch and communicating with the pyrolysis fan.

7. The two-stage household garbage pyrolysis incineration system according to claim 1, characterized in that, A vertical downward partition wall is arranged in the furnace chamber.

8. The two-stage household garbage pyrolysis incineration system according to claim 1, characterized in that, An ash valve is arranged on the root of the arch.

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