Brief Overview of the Principle of the Mother-Child Pyrolysis Furnace

Also known as: embedded twin‑rotor pyrolysis furnace, continuous twin‑rotor pyrolysis furnace, twin‑rotor oxygen‑free carbonization furnace, twin‑rotor carbonization furnace, embedded oxygen‑free pyrolysis rotary kiln, and more.

After more than a decade of research and development, Henan Jufeng Technology has launched the “Inner–Outer Embedded Pyrolysis Furnace,” which represents a technological upgrade and optimization based on the single‑unit rotary pyrolysis furnace. This furnace adopts an inner–outer embedded structure: the inner sub‑furnace has a smaller diameter than the outer main furnace, with the sub‑furnace seamlessly integrated into the interior of the main furnace in a modular configuration, creating a unique nested, series‑connected design. Through this “embedded” physical architecture, energy coupling and transfer between the two stages are ingeniously achieved. The “embedded” structure is precisely the core essence of this technology. Located within the main furnace, the high temperatures required for pyrolysis in the sub‑furnace are supplied by radiant and convective heat from the main reaction zone of the mother furnace. Because the sub‑furnace “sits” snugly within the “embrace” of the main furnace, it does not require an additional heating source—instead, it fully leverages the high temperatures generated in the cracking zone of the outer main furnace to deliver thermal radiation directly to the inner sub‑furnace, thereby providing the heat necessary for pyrolysis. By simply heating the main furnace, the furnace’s thermal supply needs are met, significantly reducing energy consumption for heat provision.

The working principle of the mother–daughter pyrolysis furnace is based on oxygen‑free thermal decomposition chemical reactions. Organic pyrolysis proceeds in two spatial stages: first, “preliminary pyrolysis” is carried out in the daughter furnace, after which the material enters the outer mother furnace for “deep cracking.” Through these two stages, a thorough cracking process is achieved. The inner daughter furnace (also known as the inner furnace or primary pyrolysis furnace) is cleverly “embedded” within the mother furnace, positioned at the center of the mother furnace. Its primary function is to initiate the first pyrolysis reaction, utilizing the thermal radiation from the outer mother furnace to drive the pyrolysis process; the temperature difference between the inner and outer furnaces is approximately 50°C. The pyrolysis feedstock first undergoes primary pyrolysis in the low‑temperature daughter furnace (at temperatures ranging from 350–750°C), then returns to the high‑temperature outer mother furnace (at temperatures ranging from 400–800°C) for secondary high‑temperature cracking (which takes place within the mother furnace), thereby achieving more complete thermal decomposition of the organic matter.

After heat supply, the flue gas undergoes rapid cooling, dust removal, alkaline spray scrubbing, and adsorption processes to ensure compliance with emission standards. This design not only enhances thermal value utilization but also results in a more compact equipment configuration that occupies a smaller footprint. The heating method employs external furnace heating with internal furnace radiation, ensuring a uniform and highly efficient cracking process.

Schematic Diagram of the Mother–Child Embedded Oxygen-Free Pyrolysis Furnace

Device photo