Carbonization or carbonization is the process of heating organic materials in the absence of oxygen to produce carbon-containing substances. This process has been used for centuries and is now the first and most important step in the production of activated carbon. This article provides a comprehensive overview of the carbonization process, the factors influencing it, and the industrial applications of this technology.
Science of Carbonization
Definition of a process
Carbonation is a process of thermal decomposition of organic materials in which they are heated in the absence or presence of very little oxygen. This results in three main products:
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carbonaceous solids (charcoal or biochar)
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Organic liquids (tar and asphalt)
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Combustible gases (methane, hydrogen and carbon monoxide)
chemical mechanism
The carbonization process includes the following steps:
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Drying (max. 150°C): Water evaporation
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Primary decomposition (150-400°C): decomposition of hemicellulose and cellulose
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Secondary degradation (400-700°C): lignin degradation
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Aromaticity (over 700°C): Formation of a graphite structure
Factors influencing the carbonization process
1. Raw materials
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Wood : medium porosity, carbon formation
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Coconut shell : fine-pored carbon
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Carbon : Large-pored carbon
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Agricultural waste : economical, but of varying quality
2. Process temperature
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Low temperature (300-400 °C): The original structure is better preserved
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Average temperature (400–600 °C): balance between efficiency and quality
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High temperature (over 600° C): increased carbon content
3. Time Remaining
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Short time: incomplete decomposition
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Optimal time: depends on the raw material (usually 1-4 hours)
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In the long term: Higher costs without significant quality improvement
4. Heating speed
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Low speed (2–5 °C/min): better process control
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Fast (10-20 °C/min): saves time but reduces quality
Industrial carbonization plants
1. Intermittent oven
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Simple and inexpensive
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Suitable for small-scale production.
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Limited control over process conditions
2. Rotary kiln
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Suitable for continuous production.
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Better control of temperature and holding time.
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3. Fluidized Bed Reactor
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Uniform heat transfer
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Shorter processing time
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Requires sophisticated equipment
4. Microwave
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Energy saving
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Uniform heating
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The limits of the industrial sphere
Application of charred products
1. Production of activated carbon
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First step towards commercial production of activated carbon
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Creation of carbon structures before activation
2. Biochar production
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Improving the properties of agricultural soils
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Carbon storage to mitigate climate change
3. Solid fuel production
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Charcoal for residential and industrial use
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Metallurgical coke in steel production
4. Chemical production
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Extraction of organic compounds from gaseous liquids
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Production of raw materials for the chemical industry
Problems and solutions of industrial carbonization
1. Pollution control
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Problem : Emissions of toxic gases and particles
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Solution : Install a gas purification and filtration system.
2. Improve energy
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Problem : High heat consumption
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Solution : Heat recovery from exhaust gases
3. Product standardization
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Problem : The quality varies from batch to batch.
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Solution : Automation and precise control of parameters.
4. Waste management
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Problem : Production of toxic organic liquids.
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Solution : Recovery and purification systems
The latest developments in carbonization technology
1. Hydrothermal carbonization
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The procedure should be performed in an aquatic environment.
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Reduce the required temperature
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Suitable for materials with high humidity.
2. Catalytic carbonization
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Lowering the process temperature with catalysts
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Improve the quality of the final product
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Better control of pore structure
3. Hybrid system
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Combination of carbonation with other processes
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Improve overall system efficiency
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Reduce operating costs
Carbonization rules
1. Product quality standards
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ASTM D1762 Coal
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ISO 13909 Metallurgical Coke
2. Environmental standards
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Reducing greenhouse gas emissions
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Air quality standards for industrial plants
3. Safety regulations
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Fire safety regulations
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Equipment Design Standards
At last
Carbonization plays a key role in the production of advanced carbon materials. Thanks to continuous improvements in process control and new methods, this technology has great application potential in industries ranging from water treatment to energy storage. A better understanding of the scientific principles and factors influencing this process will help improve manufacturing processes and increase the quality of carbon products.