Simple technologies for charcoal making

Table of Contents

Mechanical Wood Products Branch
Forest Industries Division
FAO Forestry Department


Rome, 1987

First printing 1983
Reprinted 1987

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ISBN 92-5-101328-1

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© FAO 1983

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Table of Contents


Chapter 1 - Logistics of charcoal production

1.1. Developing a fuelwood and charcoal energy policy
1.2. The energy balance concept
1.3. Calculating an energy balance
1.4. Unit processes of charcoal production

1.4.1. What is charcoal?
1.4.2. Unit processes of charcoal-making

Chapter 2 - Growing the wood raw material

2.1. Forest management and fuelwood supply
2.2. Natural forest for fuelwood
2.3. Forest types for charcoal-making
2.4. Fuelwood plantations
2.5. Cost of plantation establishment

2.5.1. Land price
2.5.2. Reforestation

2.6. Fundamental factors in fuelwood supply

Chapter 3 - Harvesting and transporting fuelwood

3.1. Key factors in harvesting and transport
3.2. Laying out a charcoal production area
3.3. Equipment for harvesting and transport

3.3.1. Felling and block preparation
3.3.2. Drying of fuelwood
3.3.3. The role of Government in maintaining forest productivity.
3.3.4. Description of a fuelwood harvesting operation.

Chapter 4 - Carbonisation processes

4.1. How wood is transformed into charcoal
4.2. Industrial safety in carbonization
4.3. Incentives and labour management

Chapter 5 - Earth pits for charcoal making

5.1. The pit method

5.1.1. Making charcoal in miniature pits
5.1.2. Making charcoal in large pits

5.2. Technical and cost data for pit charcoal production

Chapter 6 - Making charcoal in earth mounds

6.1. Types of mound
6.2. Making a typical mound or earth kiln
6.3. Casamance kiln
6.4. Collecting tar from the Casamance kiln
6.5. Cost of charcoal produced by the Casamance earth mound (from experience in Senegal)
6.6. The Swedish earth kiln with chimney

Chapter 7 - Brick kilns

7.1. The half-orange Argentine kiln

7.1.1. Preparation of the site
7.1.2. Design and construction
7.1.3. Fuelwood
7.1.4. Loading
7.1.5. Operation
7.1.6. Bricks

7.2. The Brazilian beehive kiln

7.2.1. Design
7.2.2. Construction

7.3. Slope type beehive kiln

7.3.1. The construction of slope type kiln
7.3.2. Maintenance of the kiln

7.4. The Missouri kiln

7.4.1. Design
7.4.2. Construction
7.4.3. Operation
7.4.4. The Missouri type kiln in the developing world

7.5. Charcoal production centres

7.5.1. Operational cycle of a seven kiln charcoal battery
7.5.2. Operating instructions for beehive brick kilns
7.5.3. Carbonization in slope type kilns

Chapter 8 - Metal kilns

8.1. Available designs of transportable metal kilns
8.2. Metal charcoal kiln made from oil drums
8.3. Advantages and disadvantages of transportable metal kilns
8.4. Manufacture of the TPI metal kiln
8.5. The transportation and location of kilns
8.6. Selection and preparation of site
8.7. Preparation of the raw material
8.8. Method of operating the TPI kiln

8.8.1. Tools required for a 2-3 man operation:
8.8.2. Assembly and loading the kiln
8.8.3. Lighting the kiln.
8.8.4. Reducing the draught
8.8.5. Control of charring
8.8.6. Unloading the kiln
8.8.7. Bagging of charcoal

8.9. Alternative method of operation

8.9.1. Loading
8.9.2. Lighting
8.9.3. Reducing the draught

8.10. Schedule for commercial operation
8.11. The most common operational faults
8.12. Yields of charcoal
8.13. Working life of transportable metal kilns

Chapter 9 - Transport, storage and distribution of charcoal

9.1. Unit operations in transport of charcoal
9.2. Good practice in charcoal protection and storage
9.3. Transport of charcoal in the iron and steel industry

9.3.1. Truck transport
9.3.2. Transport by rail
9.3.3. Aerial rope or cableway transport
9.3.4. Mule packs
9.3.5. Water

9.4. Distribution of charcoal

9.4.1. Charcoal properties
9.4.2. Stockholding

Chapter 10 - Using charcoal efficiently

10.1. The quality of charcoal.

10.1.1. Moisture content
10.1.2. Volatile matter other than water
10.1.3. Fixed carbon content
10.1.4. Ash content
10.1.5 Typical charcoal analyses
10.1.6. Physical properties
10.1.7. Adsorption capacity

10.2. Burning charcoal efficiently

10.2.1. How charcoal burns

Chapter 11 - Briquetting of charcoal

11.1. Properties of charcoal fines
11.2. The techniques of briquetting
11.3. Economics of briquetting
11.4. Briquetting as a cottage industry
11.5. Using fine charcoal without briquetting

Chapter 12 - Recovery of by-products from hardwood carbonization

12.1. Proligneous acid

12.1.1. The yield of pyroligneous acid
12.1.2. Refining pyroligneous acid

12.2. Small scale recovery of tars

12.2.1. Collecting the tar

Chapter 13 - Comparative performance of carbonization systems

13.1. Performance indices of carbonising equipment
13.2. Influence of wood characteristics on carbonization methods

13.2.1. Species
13.2.2. Moisture content
13.2.3. Wood size

Chapter 14 - Problems of economics and cost control in charcoal production

14.1. Economic analysis and cost control
14.2. The methods of economic project analysis
14.3. Cost control in established enterprises

14.3.1. The unit operations
14.3.2. Unit costs and budgeting
14.3.3. Supervision and management overheads

Appendix 1 - Building and Operating the Brazilian Beehive Kiln*

1. Building
2. Operation
Discharging of the kiln must start only when it is sufficiently cool.

Appendix 2 - Building a T.P.I. Steel Kiln*

1. Description
2. Manufacture

Appendix 3 - Building and operating the Argentine Half Orange Kiln

Appendix 4 - Useful conversion factors


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