Types and characteristics of biomass carbonization process
I. Traditional intermittent carbonization process
1. Earth kiln carbonization (pit type/honeycomb kiln)
Process characteristics: Biomass is stacked and covered with soil to seal, smoldering carbonization (3-7 days) Oxygen is naturally regulated through the air inlet
Core parameters: Temperature: 300-500℃ (uneven)
Charcoal yield: 15-25%
Advantages: Extremely low equipment cost (<10,000 yuan/kiln) No external energy input required
Disadvantages: Serious pollution (PM2.5 emissions exceed the standard by 20-50 times) High labor intensity (Each kiln needs manual turning)
2. Brick kiln (improved)
Upgrade point: Add flue recovery system and adopt refractory brick structure
Typical indicators: Carbonization cycle is shortened to 2-4 days and carbonization rate is increased to 20-30%
II. Continuous industrial carbonization system
1. Rotary kiln carbonization furnace
Process characteristics: inclined drum (speed 1-5rpm) with countercurrent heating temperature zone control (drying → pyrolysis → cooling)
Technical parameters:
Processing capacity: 1-10 tons/hour
Energy consumption: 80-120kWh / ton
Advantages: Continuous production (24-hour operation) Recyclable wood vinegar and combustible gas
2. Fluidized bed carbonization furnace
Innovation: Quartz sand as heat carrier (heat transfer coefficient increased by 3 times) Slightly negative pressure operation (oxygen content <3%)
Performance comparison: Indicators Rotary kiln Fluidized bed Heating rate 10℃/min50℃/min Carbon specific surface area 200-400m²/g500-800m²/g
III. New special carbonization technology
1. Wave carbonization system
Working principle: 2450MHz micro Waves directly stimulate molecular motion and precisely control temperature (±5℃)
Experimental data: Bamboo carbonization: 400℃/15min yield 38% energy consumption 40% lower than traditional methods
Business bottleneck: High equipment cost (imported system > ￥5 million) only suitable for low moisture content raw materials (<15%)
2. Hydrothermal carbonization (HTC)
Reaction conditions: 180-250℃ saturated steam environment pressure 2-4MPa
Product characteristics: Carbon microsphere structure (diameter 1-10μm) especially suitable for high humidity algae/sludge treatment
TAG: biomass carbonization
