Sawdust pyrolysis equipment adopts an advanced thermochemical conversion technology, providing a sustainable solution for sawdust recycling. It can convert this waste into high-value products, including biochar, bio-oil, and syngas. Sawdust pyrolysis, as a promising method, holds the potential to address both waste management challenges and energy security needs.
Sawdust is one of the most common solid wastes in industries, such as wood processing, furniture manufacturing, sawmills, and panel production. Traditional treatment methods not only occupy land but also cause dust pollution and carbon emissions.
The unique properties of sawdust make it an ideal raw material for biomass pyrolysis plant. It is a lignocellulosic biomass mainly composed of three components: cellulose (40-50%), hemicellulose (25-35%), and lignin (15-25%). These components undergo thermal decomposition under pyrolysis conditions, producing valuable products.
Furthermore, sawdust has many advantages as a raw material for biochar production equipment: high carbon content (approximately 45-50%), low moisture content, and wide availability. Its fine particle size also enhances heat transfer during pyrolysis process, thereby improving conversion efficiency.
Working Principle of Sawdust Pyrolysis Equipment
Sawdust pyrolysis equipment primarily utilizes pyrolysis carbonization technology to convert sawdust into biochar. This refers to the thermal decomposition process of organic matter at high temperatures (300–900°C) in an oxygen-free (or oxygen-deficient) environment.
For sawdust, the pyrolysis process, through a series of interconnected physical and chemical reactions, decomposes the complex lignocellulose structure into three main products: biochar, syngas, and bio-oil.
Key Stages of Sawdust Pyrolysis to Biochar
Sawdust pyrolysis process consists of three consecutive stages:
Drying Stage (≤200°C): Free and bound water in the sawdust evaporates. No chemical decomposition occurs in this stage, and the sawdust retains its solid structure.
Volatile Part Decomposition Stage (200–600°C): This is the critical stage, where most chemical reactions occur. Cellulose and hemicellulose decompose rapidly, releasing volatile compounds (forming bio-oil and syngas). Lignin decomposes more slowly, producing both volatile products and forming biochar. Reactions include depolymerization, dehydration, decarboxylation, and fragmentation.
Carbonization Stage (>600°C): The remaining volatile components are released from the solid matrix, and the biochar undergoes further aromatization and carbonization. With increasing temperature, the porosity, stability, and carbon density of the biochar all increase.
