Information on oil palms and the material use of oil palm trunks
The situation in the oil palm sector
Worldwide, oil palm plantations are expanding to meet the rapidly growing demand for palm oil. Demand for palm oil is driven by the food and feed sectors, the bio-chemical sector (pharmaceutics, cosmetics) and the energy industry.
According to FAO (UN Food and Agriculture Organization), an area of approx. 15 million ha were used in 2010 for the cultivation of oil palms (including only the oil-producing areas, i.e. tree age > 4 years) (figure 1). Experts from the concerned countries estimate that in some cases those figures increased considerably for the year 2012 (table 1), leading to a global cultivation area of up to 20 million ha. The leading palm oil producers are Indonesia (8 million ha), Malaysia (4.3 million ha), Thailand (0.7 million ha) and Nigeria (> 3.2 million ha).
After a tree age of 20 to 25 years, the oil yield of palms drops substantially. Therefore, 25 years is the economically justified time for replanting. Based on the approx. up to 20 million ha used today, 0.8 million ha will have to be replanted each year in the long term. In addition, a significant part of the current plantations have already been used for more than 25 years.
The general tree density of plantations is 130 to 150 oil palm trees per hectare. Oil palm trunks (OPT) which are 25 years old have a volume of 1.3 to 1.6 m³. Therefore, each replanted hectare provides approx. 170 to 240 m³ OPT. Multiplied with the 0.8 million ha/year this leads to a OPT volume of 135 to million m³/year (proportion cortex – “bark” approx. 10 %). The data provided by FAO for the plantation areas since 1960 shows that 60 million m³ OPT became available in 2010, 100 million m³ in 2023 and approx. 160 million m³ in 2030.
Today, only a small part of the OPT and the other solid biomass from oil palms is used for manufacturing or to produce energy. Usually, they are left (in heaps) to decay or are shredded and the chips spread on the soil. However, recent reports indicate that the fungi decomposing the wood chips can also infest the roots of the new oil palms. A very fast release of CO2, as well as the lost financial earnings are further negative ecological and economic consequences.
Apart from small pilot projects, OPT have not been used commercially so far. Some of the reasons are:
- the extremely high water content,
- the different density groups in the wood across the trunk (figure 2),
- the different wood structure and the wood properties of the OPT resulting from it (monocotyledons) compared to "normal" wood species,
- the difficult processing properties of palm wood, due to its structure, density of the fibre caps around the conducting tissue and the ingredients.
In addition, supply of traditional wood species and plantation wood from Southeast Asia has been scarce but sufficient.
Currently investors and enterprises interested in using this raw material have no instruments and indicators to identify and analyse the numerous purposes, the opportunities and the risks. However, it is absolutely necessary to use OPT in the future to meet the growing demand for wood-based products and especially energy.
Oil palm trunks (OPT) have a very high moisture content (150 to 600 % based on the dry mass). Due to this moisture content and the sugar and starch in the wood, fungal decay starts very fast. Preventing the decay requires special logistics in the supply chain from the logging of the palms to processing, and a very complex drying process.
Wood density and consequently the physical-technological characteristics vary significantly across the trunk (figure 2). Therefore, special process technologies and recycling strategies for the wood are necessary depending on the different density groups.
The mechanical-technological wood characteristics vary depending on the density. With regard to the density, however, they are largely similar to the traditional wood species. The tensile, pressure and bending characteristics in particular are good. Due to the wood structure, the characteristics across the fibre and the behaviour under shear stress are reduced. Detailed information are provided by Khozira Shaari et al. 1991.
Tests and pilot projects regarding the use of wood from oil palm trunks to manufacture products show great technological and economic potential. However, it is still not used on an industrial level. The main reason for this is that there are still raw material alternatives available from natural forests and that the decision-makers still focus mainly on the oil palm fruits. In general, investors do not have an affinity for the wood industry; wood from oil palms and its use have not been in the focus so far. Furthermore, there are currently no promising exploitation models available to support the decision process of potential investors for or against a use of these resources.
- Solid wood products
- Sawn timber for construction, interior fittings, furniture, packaging, transport
- Treated solid wood for longer durability
- Solid wood boards
- Cross Laminated Timber for the construction and furniture industry
- Plywood and Laminated Veneer Lumber
- Coreboard for interior fittings and furniture
- Plywood doors
- Wood-based materials
- Fibre boards (low, medium, high density)
- Oriented Structural Board (OSB)
- Parallam etc.
- Cement-bonded wood-wool building slaps, cement-bonded form parts / building blocks
- Building elements
- Flooring and wall elements
- Furniture (parts)
- Packaging materials
In Indonesia, Malaysia and Thailand (total plantation area currently approx. 13 million ha and approx. 70 million m³ OPT per year in the medium term), the material and energetic use of OPT (currently a ratio of 25 : 75 and later of 40 : 60 can be assumed) could already create 200,000 to 400,000 new jobs in the medium term and a total energy potential of 300 PJ/year (approx. 100 x 109 KWh).
The use of this raw material is overdue in light of its total potential. Indonesia, Malaysia and Thailand alone have almost 15 million ha of oil palm plantation with a wood volume of up to 80 million m³/year and a dry mass of approx. 30 million t/year in the medium and long term. The material and energetic use of OPT would lead significantly ease the situation on the local wood market and therefore of the remaining natural forests. At the same time, the potential creation of up to several hundred thousand new jobs resulting from the use of the solid biomass provides a significant economic benefit, especially in rural areas.
Based on experience from the wood industry in different countries, the use of 1,000 m³ oil palm wood reduces CO2 emissions by 2,700 t. If only half of the 40 million m³ trunk wood available per year are used, this will correspond to an annual reduction of 110 million t CO2. This could substantially offset the use of fossil energy and deforestation.