Firewood kiln with double combustion hearths and multiple fire supply paths
By using a dual-combustion furnace design and multi-fire path control, the problem of unstable firing temperature in traditional wood-fired kilns has been solved, enabling controllable ash fall and efficient heat utilization of ceramic products, and reducing the scrap rate.
Patent Information
- Application Number
- CN202520756928.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-21
- Publication Date
- 2026-01-13
- Estimated Expiration
- 2035-04-21
AI Technical Summary
Traditional wood-fired kilns suffer from unstable control over firing temperature and air supply, making it difficult to control the quality of ceramic products. The ash settling effect is highly random, resulting in low thermal efficiency and a high scrap rate.
It adopts a dual-combustion furnace design with multiple fire inlets and outlets, and is equipped with fire sealing doors, blowers and dampers. Combined with temperature measuring thermocouples, it can flexibly control the fire path and temperature. The dual-layer fuel furnace improves thermal efficiency and adjusts the ash falling effect.
It achieves controllability of firing temperature and ash settling effect, reduces ceramic scrap rate, and improves thermal efficiency and product quality stability.
Smart Images
Figure CN223795779U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of ceramic firing furnace technology, specifically relating to a wood-fired kiln that can efficiently utilize heat energy and enhance ash settling effect. Background Technology
[0002] Wood-fired kilns are traditional Chinese ceramic firing kilns that primarily use firewood as fuel. The flames and ash produced during the burning of the firewood come into direct contact with the ceramics. Due to the unpredictable nature of firewood combustion, the fired ceramics exhibit natural variations in glaze color, fire marks, and ash deposits, creating unique glaze effects that command high market value.
[0003] Traditional wood-fired kilns are typically long and narrow or dome-shaped. They consist of a combustion chamber for burning wood and a kiln chamber for holding the ceramic pieces. An inlet is located between the combustion chamber and the kiln chamber, and an outlet connects to a chimney on the outside of the kiln. Flames enter the kiln chamber from the combustion chamber and exit through the chimney. Controlling the fire and airflow in a wood-fired kiln is crucial. The operator controls the flame flow by adjusting the position and angle of the wood, and by increasing or decreasing the air supply, creating either an oxidizing or reducing atmosphere within the kiln to produce ceramic products with different effects. Improper control of the fire, temperature, and airflow can easily lead to cracking or deformation of the ceramics, and also result in poor ash settling, reducing their market value. The technical control of traditional wood-fired kilns relies heavily on the operator's experience and skills. Factors such as firing temperature, heat, and air supply are difficult to control consistently, and the ash settling effect is even more challenging. Especially during the firing process in traditional wood-fired kilns, once the clay is loaded and firing begins, the positions of the fire inlet and outlet, as well as the fire path, cannot be adjusted. This results in highly random variations in glaze color, fire marks, and ash settling, making quality control difficult and leading to a high scrap rate. Furthermore, traditional wood-fired kilns also suffer from low thermal efficiency. Summary of the Invention
[0004] The purpose of this invention is to address the shortcomings of existing wood-fired kilns and provide an improved wood-fired kiln that can effectively control the firing temperature, air supply, and ash settling effect, enhance the controllability of glaze color changes, fire marks, and ash settling, reduce the scrap rate, and improve thermal efficiency.
[0005] The technical solution adopted by this utility model is as follows:
[0006] A wood-fired kiln with dual combustion chambers and multiple fire supply paths includes a kiln chamber, a combustion chamber connected to and located at the front end of the kiln chamber, a flue gas chamber connected to and located at the rear end of the kiln chamber, and a chimney connected to the flue gas chamber. At least two fire inlets are provided from bottom to top on the connecting wall between the combustion chamber and the kiln chamber. A fire-sealing door, which can be raised and lowered close to the fire inlets, is provided on the outer side of the connecting wall between the combustion chamber and the kiln chamber. At least two fire outlets are provided from bottom to top on the connecting wall between the kiln chamber and the flue gas chamber. The lower part of the combustion chamber is equipped with a double-layer fuel furnace, including a wood-burning chamber and a charcoal-burning chamber located below the wood-burning chamber. An upper grate is installed between the wood-burning chamber and the charcoal-burning chamber. A wood-adding door and a charcoal-adding door are respectively installed at the front end of the wood-burning chamber and the charcoal-burning chamber. A lower grate is installed at the bottom of the charcoal-burning chamber. An ash-collecting chamber is installed below the charcoal-burning chamber. An air inlet and an ash-cleaning door are opened on the side of the ash-collecting chamber. A blower is installed at the air inlet. An operable damper is installed on the side of the flue gas chamber. A temperature measuring thermocouple is installed in the kiln chamber.
[0007] Furthermore, the fire inlet is provided with 2 to 3 locations; the fire outlet is provided with 2 to 3 locations.
[0008] Furthermore, a lifting ring is provided at the top of the fireproof door, and a lifting mechanism is provided above the combustion chamber, with a hook that can be hooked onto the lifting ring.
[0009] Furthermore, the combustion chamber, kiln chamber, and flue gas chamber are all constructed with refractory materials.
[0010] This utility model has at least the following advantages:
[0011] 1. The combustion chamber of this utility model features a double-layered fuel furnace. The lower charcoal-burning chamber can be filled with charcoal, while the upper firewood-burning chamber can be filled with firewood. The ignited charcoal heats the cold air blown by the blower before it enters the firewood-burning chamber, ensuring that the temperature of the firewood-burning chamber does not decrease, and the subsequent firing temperature into the kiln chamber also remains stable, thus improving thermal efficiency. Simultaneously, by controlling the blower's airflow, the amount of ash blown into the kiln chamber can be controlled, improving the ash settling effect on the ceramics as needed.
[0012] 2. This utility model features multiple fire inlets and a fire-sealing door that can be raised and lowered close to the fire inlets. The number of fire inlets opened and closed is controlled by raising and lowering the fire-sealing door, thereby achieving flexible control of the fire path and furnace temperature inside the kiln. Simultaneously, at least two fire outlets located at different heights are provided, allowing for temperature and fire path adjustment at different heights within the kiln. Effective control of the fire path and furnace temperature significantly reduces deformation and breakage of fired products, while also allowing for adjustment and control of ash settling, resulting in more consistently high-quality products.
[0013] 3. This utility model is equipped with a flue-type exhaust chamber. When firing clay blanks, the damper is closed, and the flue gas can be smoothly discharged from the chimney. During the firing process and after the fire is extinguished, the damper can be opened and the fire outlet can be blocked to control the kiln temperature, reduce the scrap rate, and improve the ash collection effect. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of this utility model;
[0015] Figure 2 This is a top view of the present invention (the lifting mechanism is omitted). Detailed Implementation
[0016] The contents of this utility model will be further described below with reference to the accompanying drawings.
[0017] like Figure 1 , Figure 2As shown, a wood-fired kiln with dual combustion chambers and multiple fire supply paths includes a kiln chamber 2, a combustion chamber 1 connected to the kiln chamber and located at the front end of the kiln chamber, a flue gas chamber 3 connected to the kiln chamber and located at the rear end of the kiln chamber, and a chimney 4 connected to the flue gas chamber. The combustion chamber 1, kiln chamber 2, and flue gas chamber 3 are all constructed of refractory bricks, and are built sequentially adjacent to each other. A kiln door 2a is provided on the front of the kiln chamber to allow the blanks to be fired to be fed into the kiln. At least two fire inlets 5 are provided from bottom to top on the connecting wall between the combustion chamber and the kiln chamber. A fire-sealing door 7, which can be raised and lowered close to the fire inlets, is provided on the outer side of the connecting wall between the combustion chamber and the kiln chamber. At least two fire outlets 6 are provided from bottom to top on the connecting wall between the kiln chamber and the flue gas chamber. The fire-sealing door is made of refractory material; in this embodiment, it is made of silica insulation board. By raising and lowering the fire-sealing door, the fire inlet can be fully opened or partially blocked, thereby controlling the fire path and temperature entering the kiln chamber. The lifting mechanism 15 controlling the raising and lowering of the fire-sealing door can use existing lifting mechanisms, such as electric hoists or wire winches. In this embodiment, an electric hoist is installed above the combustion chamber, and a lifting ring 7a is installed at the top of the fire-sealing door, with the electric hoist's hook hooked onto the lifting ring. Typically, 2-3 fire inlets 5 and fire outlets 6 are provided; in this embodiment, 3 fire inlets and 3 fire outlets are provided. The lower part of the combustion chamber 1 is provided with a double-layer fuel furnace, including a wood-burning chamber 1a and a charcoal-burning chamber 1b located below the wood-burning chamber. An upper grate 8 is provided between the wood-burning chamber and the charcoal-burning chamber. A wood-adding door 1c and a charcoal-adding door 1d are respectively provided at the front of the wood-burning chamber and the charcoal-burning chamber. A lower grate 9 is provided at the bottom of the charcoal-burning chamber. Below the charcoal-burning chamber is an ash collection chamber 10. An air inlet 11 and an ash-cleaning door are located on the side of the ash collection chamber. The ash-cleaning door can be located next to the air inlet or on another side of the ash collection chamber (not shown in the figure). A blower 12 is installed at the air inlet. An operable damper 13 is installed on the side of the exhaust chamber 3. The damper can be opened, and the fire outlet can be blocked with refractory bricks to adjust the temperature and fire path at different heights within the kiln. When firing clay bricks, the damper is closed, allowing flue gas to be smoothly discharged from the chimney. During firing and after firing is completed and the kiln is extinguished, the damper can be opened as needed, and the fire path and kiln temperature can be controlled by blocking the fire outlet. A thermocouple 14 is installed inside the kiln chamber 2 to monitor the temperature inside the kiln. By monitoring the temperature inside the kiln, the number of fire inlets and outlets to be opened and the start / stop and airflow of the blower can be controlled accordingly.
[0018] The working process of this utility model is as follows:
[0019] S1. Open the kiln door 2a, place the blanks to be fired into the kiln chamber 2, and close the kiln door;
[0020] S2. Open the firewood adding door 1c and the charcoal adding door 1d, and add charcoal to the lower charcoal burning chamber 1b and firewood to the upper firewood burning chamber 1a respectively;
[0021] S3. Ignite the charcoal, start the blower 12 and control the airflow. The cold air blown out is heated in the charcoal chamber and then passes through the upper grate 8 into the wood-fired chamber, heating and burning the wood. The temperature of the wood-fired chamber will not decrease due to the cold air, ensuring the subsequent firing temperature in the kiln chamber and improving thermal efficiency. The high-temperature flames in the wood-fired chamber enter the kiln chamber through the fire inlet to fire the ceramic body. During this stage, the blower's airflow can be controlled as needed to control the amount of ash blown into the kiln chamber, improving the ash settling effect of the ceramics. During the firing process, the temperature inside the kiln chamber is monitored by the thermocouple 14 to determine the number of fire inlets and outlets to be opened, as well as the blower's airflow. According to the kiln firing process requirements, the fire shut-off door can be lowered to block part of the fire inlet, or raised to open part or all of the fire inlets. At the same time, when necessary, the air damper 13 can be opened to block part of the fire outlet or open all of the fire outlets. By controlling the fire inlet, fire outlet, and blower, the fire path and temperature inside the kiln chamber can be controlled. The ash produced by burning firewood and charcoal falls into the ash collection chamber 10 through the lower grate 9, and can be cleaned periodically.
[0022] S4. After the clay body is fired, turn off the blower and extinguish the fires in the wood-fired and charcoal-fired chambers. Let the fired product cool with the kiln. Open the kiln door and remove the fired product.
[0023] This invention improves upon traditional wood-fired kilns, effectively controlling firing temperature, air supply, and ash settling effect, enhancing the controllability of glaze color changes, fire marks, and ash settling, reducing scrap rate, and improving thermal efficiency.
[0024] The above embodiments and accompanying drawings are only typical embodiments of the present utility model and are not intended to limit the structure and shape of the present utility model. For those skilled in the art, the structure and shape of the combustion chamber, kiln chamber, flue gas chamber, chimney, etc. can have many variations, and these variations all fall within the protection scope of the present utility model.
Claims
1. A wood-fired kiln with dual combustion chambers and multiple fire supply paths, characterized in that, It includes a kiln chamber (2), a combustion chamber (1) connected to the kiln chamber and located at the front end of the kiln chamber, a flue gas chamber (3) connected to the kiln chamber and located at the rear end of the kiln chamber, and a chimney (4) connected to the flue gas chamber; at least two fire inlets (5) are provided from bottom to top on the connecting wall between the combustion chamber and the kiln chamber, and a fire-sealing door (7) that can be raised and lowered close to the fire inlets is provided on the outside of the connecting wall between the combustion chamber and the kiln chamber; at least two fire outlets (6) are provided from bottom to top on the connecting wall between the kiln chamber and the flue gas chamber; the lower part of the combustion chamber (1) is provided with a double-layer fuel furnace, including a combustion chamber for the combustion chamber. The firewood chamber (1a) and the charcoal burning chamber (1b) located below the firewood chamber are provided with an upper grate (8) between the firewood chamber and the charcoal burning chamber. A firewood adding door (1c) and a charcoal adding door (1d) are respectively provided at the front end of the firewood chamber and the charcoal burning chamber. A lower grate (9) is provided at the bottom of the charcoal burning chamber. An ash collection chamber (10) is provided below the charcoal burning chamber. An air inlet (11) and an ash cleaning door are provided on the side of the ash collection chamber. A blower (12) is provided at the air inlet. An openable air door (13) is provided on the side of the smoke exhaust chamber (3). A temperature measuring thermocouple (14) is provided in the kiln chamber (2).
2. A wood-fired kiln with dual combustion chambers and multiple fire supply paths according to claim 1, characterized in that, The fire inlet (5) is provided with 2 to 3 outlets; the fire outlet (6) is provided with 2 to 3 outlets.
3. A wood-fired kiln with dual combustion chambers and multiple fire supply paths according to claim 1 or 2, characterized in that, The top of the fire door (7) is provided with a lifting ring (7a), and a lifting mechanism (15) is provided above the combustion chamber. The lifting mechanism is provided with a hook that can be hooked onto the lifting ring.
4. A wood-fired kiln with dual combustion chambers and multiple fire supply paths according to claim 1 or 2, characterized in that, The combustion chamber (1), kiln chamber (2), and smoke exhaust chamber (3) are all constructed with refractory materials.