COMPACT DOMESTIC WASTE PYROLYSIS APPARATUS WITH INTEGRATED MULTI-CHAMBER SECONDARY COMBUSTION CHAMBER

Abstract

The present invention relates to the technical field of pyrolysis technology, and specifically discloses a compact domestic waste pyrolysis apparatus featuring an integrated multi-chamber secondary combustion chamber. The apparatus consists of a pyrolysis furnace, which incorporates both a pyrolysis chamber and a secondary combustion chamber. The upper section of the pyrolysis chamber is provided with a communication hole that connects to the secondary combustion chamber. In this apparatus, the pyrolysis chamber and the secondary combustion chamber are closely integrated. The generated pyrolytic gas directly enters the secondary combustion chamber, effectively preventing coking and significantly reducing the frequency of failures. The secondary combustion chamber absorbs radiant heat from the pyrolysis chamber, maintaining its temperature consistently above 850 C., which is conducive to the complete combustion of the pyrolytic gas and maximizes thermal energy release. This promotes the complete decomposition of dioxin precursors, reduces the likelihood of dioxin reformation, lowers the initial emission concentration of dioxins, and decreases the required dosage of adsorbent activated carbon. The highly integrated design of the secondary combustion chamber and the pyrolysis chamber optimizes space utilization and reduces the equipment's footprint, thereby lowering investment and construction costs.

Claims

1. A compact domestic waste pyrolysis apparatus with an integrated multi-chamber secondary combustion chamber, comprising a pyrolysis furnace (1), characterized in that: said pyrolysis furnace (1) comprises a pyrolysis chamber (2) and a secondary combustion chamber (3), wherein an upper portion of said pyrolysis chamber (2) is provided with a communication hole connected to said secondary combustion chamber (3); the exterior of said pyrolysis chamber (2) is provided with a first high-temperature insulation wall (4); the top of said pyrolysis furnace (1) is provided with a feed hopper (5) and communicates with said pyrolysis chamber (2), said feed hopper (5) being equipped with a sealing assembly; the bottom wall of said pyrolysis furnace (1) is provided with a rotating furnace grate (6) communicating with said pyrolysis chamber (2); the slag discharge outlet (7) is provided below said rotating furnace grate (6); a lower sidewall portion of said rotating furnace grate (6) is provided with a primary air inlet (8); said secondary combustion chamber (3) internally defines a secondary combustion cavity; said secondary combustion chamber (3) is further provided with a second high-temperature insulation wall (9) configured to partition said secondary combustion cavity into a plurality of sub-chambers; said plurality of sub-chambers are connected sequentially; and an output end of a final sub-chamber among said plurality of sub-chambers is provided with a flue gas outlet (10).

2. The apparatus according to claim 1, wherein said sealing assembly comprises a first sealing door (11) and a second sealing door (12), with the said first sealing door (11) disposed above the said second sealing door (12).

3. The apparatus according to claim 2, wherein communication ports between said plurality of sub-chambers are arranged at varying heights.

4. The apparatus according to claim 3, wherein a front lower portion of said rotating furnace grate (6) is further provided with a first inspection port (13).

5. The apparatus according to claim 4, wherein said pyrolysis chamber (2) is divided sequentially from top to bottom into a preheating and drying zone (14), a pyrolysis zone (15), and an oxidation and slagging zone (16).

6. The apparatus according to claim 5, wherein said pyrolysis furnace (1) is further provided with a first burner interface (17) that communicates with said oxidation and slagging zone (16), and wherein a second inspection port (18) is provided below said first burner interface (17).

7. The apparatus according to claim 6, wherein said pyrolysis furnace (1) is further provided with a second burner interface (19) that communicates with said secondary combustion chamber (3).

8. The apparatus according to claim 7, wherein said pyrolysis furnace (1) is further provided with a secondary air inlet (20) that communicates with said secondary combustion chamber (3).

9. The apparatus according to claim 8, wherein: said second high-temperature insulation wall (9) is cross-shaped; said plurality of sub-chambers comprises sequentially a first sub-chamber (21), a second sub-chamber (22), a third sub-chamber (23), and a fourth sub-chamber (24); said first sub-chamber (21) communicates with said pyrolysis chamber (2); and said flue gas outlet (10) communicates with said fourth sub-chamber (24).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is a front cross-sectional schematic view of the structure according to the present invention.

[0023] FIG. 2 is a top cross-sectional schematic view of the structure according to the present invention.

[0024] Reference Numerals: 1: pyrolysis furnace; 2: pyrolysis chamber; 3: secondary combustion chamber; 4: first high-temperature insulation wall; 5: feed hopper; 6: rotating furnace grate; 7: slag discharge outlet; 8: primary air inlet; 9: second high-temperature insulation wall; 10: flue gas outlet; 11: first sealing door; 12: second sealing door; 13: first inspection port; 14: preheating and drying zone; 15: pyrolysis zone; 16: oxidation and slagging zone; 17: first burner interface; 18: second inspection port; 19: second burner interface; 20: secondary air inlet; 21: first sub-chamber; 22: second sub-chamber; 23: third sub-chamber; 24: fourth sub-chamber.

DETAILED DESCRIPTION OF THE INVENTION

[0025] The technical solutions in the embodiments of the present invention are described below clearly and comprehensively with reference to the accompanying drawings. It should be understood that the described embodiments represent only a portion of the embodiments of the present invention, rather than all of them. Any other embodiments that can be derived by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0026] Referring to FIGS. 1-2, the invention provides a compact domestic waste pyrolysis apparatus featuring an integrated multi-chamber secondary combustion chamber. The apparatus comprises a pyrolysis furnace 1 which includes a pyrolysis chamber 2 and a secondary combustion chamber 3. The upper portion of the pyrolysis chamber 2 is provided with a communication hole connected to the secondary combustion chamber 3.

[0027] The exterior of the pyrolysis chamber 2 is enclosed by a first high-temperature insulation wall 4.

[0028] The front lower portion of the rotating furnace grate 6 is further provided with a first inspection port 13.

[0029] The top of the pyrolysis furnace 1 is provided with a feed hopper 5 that communicates with the pyrolysis chamber 2. The feed hopper 5 is equipped with a sealing assembly. The bottom wall of the pyrolysis furnace 1 features a rotating furnace grate 6 that also communicates with the pyrolysis chamber 2. a slag discharge outlet 7 positioned below the rotating furnace grate 6. A lower sidewall portion of the rotating furnace grate 6 is provided with a primary air inlet 8.

[0030] The secondary combustion chamber 3 defines an internal secondary combustion cavity. The secondary combustion chamber 3 is further provided with a second high-temperature insulation wall 9 that divides the secondary combustion cavity into a plurality of sub-chambers. The plurality of sub-chambers are connected sequentially, and an output end of the final sub-chamber is provided with a flue gas outlet 10.

[0031] In this embodiment, the sealing assembly consists of a first sealing door 11 and a second sealing door 12. The first sealing door 11 is disposed above the second sealing door 12. Waste falls into the feed hopper 5 for buffering. Once a sufficient amount accumulates, the first sealing door 11 in the upper part of the feed hopper 5 opens, allowing the waste to fall into the chute. The first sealing door 11 then closes, followed by the opening of the second sealing door 12, allowing the waste to fall onto the surface of the waste bed in the pyrolysis chamber 2. Finally, the second sealing door 12 closes.

[0032] In this embodiment, the pyrolysis chamber 2 is divided sequentially from top to bottom into a preheating and drying zone 14, a pyrolysis zone 15, and an oxidation and slagging zone 16. The pyrolysis furnace 1 is further provided with a first burner interface 17 that communicates with the oxidation and slagging zone 16. A second inspection port 18 is provided below the first burner interface 17.

[0033] A temporary ignition device (e.g., a diesel burner) is connected via the first burner interface 17 (to the oxidation and slagging zone 16) to facilitate start-up. The ignition device is started to heat the oxidation and slagging zone 16. By adjusting the primary air volume (gradually increasing from 0.2 m.sup.3/h to the design value), the temperature of the oxidation and slagging zone 16 is stabilized above 850 C., while the temperature in the core area of the pyrolysis chamber 2 is monitored(via temperature measurement points on the furnace wall) to ensure the preheating and drying zone 14 200 C. and the high-temperature pyrolysis zone 15 600 C. Primary air passes through gaps in the rotating furnace grate 6 and contacts the carbonized material. The carbonized material combusts under high-temperature, oxygenated conditions, generating substantial heat that supplies thermal energy for the pyrolysis/gasification of material in the pyrolysis zone 15 above, thereby maintaining stable temperatures across the bed zones. After complete combustion of the carbonized material, remaining combustibles in the waste, including harmful pollutants such as dioxins, are thoroughly oxidized and decomposed into slag. The slag is broken up by the rotating furnace grate 6 and discharged through the slag discharge outlet 7. By limiting the primary air supply, as the carbonized material burns, oxygen in the air is consumed, creating an oxygen-deficient environment for the middle and upper pyrolysis zone 15.

[0034] In this embodiment, the second high-temperature insulation wall 9 is cross-shaped. The plurality of sub-chambers are arranged sequentially as a first sub-chamber 21, a second sub-chamber 22, a third sub-chamber 23, and a fourth sub-chamber 24. The first sub-chamber 21 communicates with the pyrolysis chamber 2, and the flue gas outlet 10 communicates with the fourth sub-chamber 24. The communication ports between the plurality of sub-chambers are arranged at varying heights. The pyrolysis furnace 1 is further provided with a second burner interface 19, and a secondary air inlet 20 both communicating with the secondary combustion chamber 3. When pyrolytic gas enters the secondary combustion chamber 3, a small amount of supplemental fuel may be introduced if necessary via the second burner interface 19 to raise the temperature of the first sub-chamber 21 to 850 C. After reaching the target temperature, auxiliary combustion is stopped, and the temperature is maintained by combustion of the pyrolytic gas itself.

[0035] The feed rate is gradually increased to the design value (e.g., 500 kg/h), while the secondary air volume is adjusted to maintain the excess air coefficient in the secondary combustion chamber 3 stable between 1.05 and 1.2, the flue gas temperature at the flue gas outlet 10 is 850 C., and the residence time is 3 seconds.

[0036] Continuous feeding via the feed hopper 5 maintains a stable material level in the pyrolysis chamber 2 (approximately of the furnace height). The double sealing doors operate alternately (first the first door opens for feeding and closes, then the second door opens to prevent air leakage).

[0037] The rotating furnace grate 6 operates continuously at low speed (0.5-1 r/min), breaking up the slag formed in the oxidation and slagging zone 16 and discharging it through the slag discharge outlet 7. The slag discharge temperature is monitored (must be <50 C.) to ensure the loss on ignition of the slag is <3%.

[0038] Temperatures in various zones of the pyrolysis chamber 2, temperatures in the sub-chambers of the secondary combustion chamber 3, primary/secondary air volumes, and flue gas composition (HCl, SO.sub.2, NOx, etc.) at the flue gas outlet 10 are recorded in real time. When the temperature in the pyrolysis zone 15 falls below 700 C., the first burner can be activated to maintain the desired temperature. The feed rate and primary air volume are adjusted according to operational conditions.

[0039] Every 8 hours, the communication ports in the secondary combustion chamber 3 are checked via inspection ports for patency (since there are no pipes, only passages between chambers require inspection). Any minor ash accumulation can be cleaned by adjusting the secondary air pressure (briefly increasing by 10%) to purge the passages.

[0040] For shutdown, feeding is stopped first while fans continue running. After the material in the pyrolysis chamber 2 is substantially consumed (approximately 1 hour), and the temperature in the pyrolysis zone 15 drops below 500 C., the primary air fan, secondary air fan, and induced draft fan are turned off. The flue gas outlet 10 remains slightly open to allow natural cooling of the apparatus (cooling rate not exceeding 200 C. per hour to avoid furnace cracking). Once the internal temperature drops below 100 C., the inspection ports and slag discharge outlet 7 are opened to remove residual slag and inspect internal components for wear, preparing for the next start-up.

[0041] Reference to an embodiment in this document indicates that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The use of the term embodiment in various places in the specification does not necessarily refer to the same embodiment, nor is it specifically limited to being independent of or associated with other embodiments. In principle, in this application, provided no technical contradiction or conflict exists, the various technical features mentioned in the embodiments can be combined in any manner to form corresponding implementable technical solutions.

[0042] Unless otherwise specified, the technical terms used herein have the same meanings as those typically understood by a person skilled in the technical field to which this application belongs. The use of related terms herein is solely intended to describe specific embodiments and is not meant to limit the scope of the application.

[0043] Although the embodiments of the present invention have been shown and described, it should be understood by those skilled in the art that various changes, modifications, substitutions, and alterations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.