How To Do Wood Processing


During the last several decades, forest product processing technologies have undergone extraordinary advances in some of the above categories. Improvements have been achieved in terms of recovery rates, higher qualities in terms of durability and protection, higher utilization of NTFPs such as bagasse, various grain stalks and bamboo, as well as the development of new products such as reconstituted wood-panels. Progress has not been homogenous in all the forest product utilization categories. Even though there is only little information available on the subjects of technology acquisition, adaptation and innovation for the forest-based industrial sector (Contreras-Hermosilla and Gregersen, 1991), it is clear that sawmilling has been far less affected by the spread of innovations than the manufacturing of panel products. There is still a high number of outdated mills in operation which have very low recovery rates, frequently less than 40 percent.

How To Do Wood Processing Wood Processing4The technological changes that have taken place within the Region have not occurred randomly. Many of the technologies that are increasingly adopted and adapted have been developed in industrial countries. Some of them, such as medium density fibreboard (MDF) production technologies had been in use, tested and refined for more than 25 years before they featured more prominently in the Region. Most the machinery is still imported, predominantly, from Europe. Others such as oriented strandboard (OSB) production does not exist yet in most countries of the Region and its market is underdeveloped.

The following four reasons account for the contemporary developments in those categories that have experienced changes and those that have remained largely stagnant in terms of modernization:

· decreasing raw material supply;
· reduced availability of large-sized timber;
· increasing responsiveness to environmental pressures; and
· government policies to develop domestic wood-based industries.

As a result of government support, the number of processing plants has increased substantially and products have become diversified. The first three factors disclose why the traditional sawnwood sector has lagged behind the other sectors. They also explain the declining importance of the plywood sector which has been significantly affected by a reduction in wood supplies as well as competition with MDF whose production costs are considerably lower. In Indonesia, the raw material shortage resulted in production capacities as low as 50 percent for some firms, while older facilities with inefficient machines opted to close down (Adhar, 1996). Excess capacities are also reported for Sabah (Tay and Abi, 1996), which did not, however, affect the lifting of the log export ban that had been imposed in 1993 (Anon, 1996d).

In general, the wood processing industry is currently undergoing major structural changes with a gradual switch from the production of timber products using large diameter trees to those utilizing smaller diameter from second cuts, as well as moving toward plantations and the estate sector. Product diversity has increased to such an extent and developments have been so variable that only three more recent developments will be used to illustrate which further changes might be expected in the following decade. For this purpose the developments in the MDF category, the increased use of rubberwood and the potential of oil palm as a raw material for the wood-based panel industry, will be described.

Medium Density Fibreboard Production

How To Do Wood Processing Wood Processing1The recent developments in the MDF sector are very similar to the earlier developments in the plywood sector. The main difference is that the latter was a response to government policies promoting domestic wood-based industries while MDF production plants sprang up because of the raw material shortages that have become increasingly evident during the last few years and the opportunity of using formerly untapped resources. Another difference is in the installed capacity of MDF which lags behind the plywood sector. Globally, it stands at 15 million m3/year. By the end of 1996, the Asia-Pacific Region is expected to become the leader in MDF production with an installed capacity of well over 5 million m3/year (Anon, 1995a).

Important raw materials for MDF include radiata pine (New Zealand), mixed tropical species (Japan), rubberwood (Thailand), bagasse (Pakistan, China and Thailand) and cotton stalks (India) (Wadsworth, 1995). The only raw material used in Malaysia is rubberwood, in contrast to particleboard or cement-bonded products which rely more on a mixture of species and wood waste. The light colour of rubberwood and uniform texture provide an ideal fibre resource for MDF production.

The MDF production process involves in the first steps debarking and chipping. Cleaned chips are cooked in a digester and refined into wood fibres which are then mixed with resin and wax. The mixture of wet fibre, resin and wax is dried and transported to the mat former before it is pressed to produce a continuous mat. In the final processing stage it is trimmed, sanded and cut to specified dimensions. Depending on customer requirements board thickness varies between 2.5 and 32 mm.

MDF and OSB have emerged as price competitive alternatives to the more traditional products such as plywood, particleboard and hardboard. With similar characteristics to plywood products, their greatest advantage is that low quality and low value raw materials (including non-wood fibres) can be turned into high value and high quality wood-panels. This clarifies why their production costs are about 50 percent lower (Adhar, 1996). Because of the desirable and user-friendly physical properties and favourable machining properties, MDF has a variety of end-uses and can replace tropical hardwood timbers for furniture. The production process can virtually use all wood species of minimum log diameter down to 5 cm. In addition, it is marketed as an environmentally friendly product which relies on sustainable resources such as rubberwood, radiata pine and non-wood fibres. The combination of these advantages testify to the massive investment in MDF production plants.

The Rubberwood Success Story in Malaysia

Until about fifteen years ago, the commercial value of rubberwood as a raw material for the wood processing industry was negligible. Due to the high sugar content, rubberwood biodegrades rapidly. In addition, it is susceptible to insect infestations after felling. Notwithstanding these problems, rubberwood has always been an under-utilized raw material with potential, particularly with the onset of log shortages from natural forests. Hence, as is the case with MDF and oil palm (see below), the initial impetus for investigating its potential came from the need to search for alternative sources for an ailing sawmilling and wood processing industry, particularly in Malaysia (Hong, 1995). While Malaysia was not the first country to utilize rubberwood, it was the first one to export it successfully.

Today the significant utilization of rubberwood can be attributed to the combination of research and development by the Forest Research Institute Malaysia and the development of marketing strategies by private companies and related government agencies (Hong, 1995). At present, rubberwood comes exclusively from plantations established for latex production. With an expected increase in demand and shortage in supply, the growing of rubber trees for the sole purpose of timber production is envisioned. This would dramatically increase recovery rates which are currently as low as 25 percent.

How To Do Wood Processing Wood Processing5Most affected by the research and marketing success have been the furniture and panel products industries. In Malaysia, rubberwood has out-performed many of the traditional light-coloured species used in the production of furniture. Its availability and low price has resulted in the expansion of the furniture industry. Of the approximate USD 600 million for furniture export values in Malaysia, around 70 percent is from rubberwood.

The growth in the MDF sector in Malaysia is also the direct consequence of rubberwood abundance. As reported by Hong (1995), rubberwood has all the required ingredients to make it successful in the wood-panel sector. It is a homogenous raw material, available in large volumes and a renewable resource - a very important criterion for the sensitized wood processing industry in Malaysia. The benefits from making rubberwood attractive for the wood processors and ultimately the consumer have been spread fairly widely. Today smallholders and farmers can sell their trees per truck load to the industry, not only on Peninsular Malaysia but also in Sarawak.

Oil Palm Fibre as an Alternative Raw Material

The wood processing industry has recently experienced shortages in rubberwood supply. There are a number of reasons for this latest development. First, climatic (prolonged wet periods) conditions render harvesting of rubberwood, particularly on steeper slopes, inefficient. One has to remember that rubber plantations were established for latex not for wood production. Second, the resource is not available in more desirable large blocks affecting economies of scale. And third, even rubberwood turns out to be a finite (at least in the short- to medium-term) resource as demand outstrips supply. Therefore, the industry is already in search of alternative raw materials. Acacia mangium is receiving increasing attention. Its characteristics are well known though many questions regarding its silviculture and suitability for the timber industry still remain.

The search has recently included oil palm, plantations of which are increasingly replacing those of rubber in Southeast Asia. In common with rubber, it is an under-utilized resource with potential application in a number of industrial sectors. The empty fruit bunches of oil palm are used as mulch, boiler fuel, fertilizer, and for the production of car cushions and mattresses. Research is currently investigating the use of oil palm fibres for various wood-based boards, pulp and paper, mushroom cultivation and as animal feed (Akmar et al., 1996). The fibrous strands of the trunks and fronds are suitable for manufacturing pulp and paper, chipboard, and cement/gypsum bonded particleboard (Anon, 1995b). The fibres of the empty fruit bunches can be used for laminated isotropic fibreboard, cementboard, and pulp.

Research results suggest that the quality and physical characteristics of fibreboard made from the empty fruit bunches of oil palms surpass those of particleboard. In general, their quality is comparable to rubberwood particleboard (Yayah et al., 1995). In Malaysia, the first companies have produced furniture from oil palm fibres. Its increased use is viewed as achieving zero waste in the oil palm industry (Anon, 1995b). This translates into substantial cost savings which partially explains the enthusiasm of some companies to venture into panel manufacturing.

Outlook

The current developments in the wood processing sector are a response to a mixture of emerging constraints and opportunities that have existed for a much longer time. Advanced machinery and technologies for more efficient wood use have existed in industrial countries for decades. However, their adoption was neglected in the Region (predominantly in the tropical countries) because first, the natural forests were viewed as an infinite resources, and second, limits to harvesting large-sized timber were not expected so soon. Looking at the processing capacity of wood processing mills and the future supply scenario of timber from natural forests, the main concern that has arisen is the future availability of logs. This concern has stimulated an entry into the reconstituted wood-panel industry as well as the use of formerly under-utilized or discarded raw materials, as the examples from Malaysia have revealed.

Wood-panel products with their advantages, in terms of cost and technical property, have developed from plywood to particleboard and MDF, through an evolution from using basically solid wood to using fibres of a variety of products. This development has not only produced more homogenous products, but reconstituted panel production also has much higher recovery rates than sawntimber or plywood. Furthermore, reconstituted panels can be made from a variety of products. Compared to solid wood and plywood, large uniform panel sizes free of any natural defects can be obtained (Yayah et al., 1995). The tremendous growth of the wood-based panel industry is clearly a reflection of the limited wood availability.

With further advances in lamination possibilities, special grades and properties, including moisture resistance, fire retardance and exterior grades, it can be safely assumed that the current growth rates will continue. The expected growth in ready-to-assemble furniture will increase the awareness of the special characteristics and advantages of wood-based panels, particularly MDF and OSB. In addition, new factories can be erected with relative ease. The decreasing supply of large diameter logs will require a further restructuring of the plywood industry. Depending on the success of marketing strategies for boards such as MDF or OSB, the tropical plywood sector will shrink faster than expected, at least in relative terms, as substitutes and more efficient uses are developed (Anon, 1995c). Reconstituted panels will not be able to substitute all solid wood products but laminating technologies will assist in making them attractive to consumers. Also, finger jointing technologies will allow manufacturers to arrived at desired length of the final products.

Vertical and horizontal integration of productive units will provide opportunities to increase employment and efficiency of wood use. Currently there are no incentive structures for reducing wood waste during harvesting operations in natural forests, or for transporting the waste to processing mills (Kadir et al., 1994). In fact, there is even no interest in extracting waste when no royalties and fees are charged (Shaharuddin, pers. comm., 1996).

The most logical way to overcome high extraction and transportation cost is to pre-process timber at the logging site. As discussed by Kadir et al. (1994), there are several institutional, social and political problems related to licensing portable sawmills. An alternative, particularly in the vicinity of reconstituted panel manufacturers, is the use of mobile chippers which will become viable once infrastructure has been improved and rubberwood has lost its competitive edge over wood waste. Mobile chippers will be particularly attractive for secondary forests where the mean diameter of trees can be expected to be far lower than in the "primary" forest.

As Wadsworth (1995, p. 23) explained for MDF, the development of wood product consumption does not lie in the "introduction of new technologies or exotic fibres, but rather, in the more widespread application of sound and vigorous marketing". Notwithstanding the need for better targeted marketing to increase the appeal of wood-based panels to consumers, it is also possible that new technologies will achieve greater structural properties of panels and that recycled materials such as plastic can be used in manufacturing environmentally friendly composites.

How To Do Wood Processing Wood Processing3 1The previous discussion has omitted any mention of potential advances in sawmilling. In comparison to how other categories within the wood processing sector will be affected by technological changes, the developments in the sawmilling sector will be less dramatic. The older and least efficient mills will slowly be phased out and replaced with new mills capable of maintaining or even improving recovery rates while their supplies are changing to smaller diameter logs. Here again, the technologies are already available. It is only a matter of providing appropriate incentives to encourage producers to upgrade their facilities.

Pulp and paper have also seen enormous growth rates over the last decade. New technologies for pulping mixed tropical hardwoods created a market for salvage timber (Byron, 1996). A change that will affect the industry are stricter environmental regulations regarding effluent discharge. A more important aspect for the pulp and paper industry (particularly the large scale complexes) is whether it will be able to satisfy its raw material demand. Most manufacturers hope to eventually rely on plantations of fast growing trees only. Recent reports summarized by Nilsson (1996) showed that they may be overly optimistic. One alternative would be to substitute non-wood fibres for wood fibres (Wilson, 1995). At present the main non-wood pulping capacities are located in China (74 percent) and India (6 percent). The potential of non-wood fibres is great but their use has also several drawbacks. Therefore, it is doubtful that in the next ten to fifteen years "they will become a hot item for the pulp and paper industry to tackle", as Croon predicts (1995, cited in Nilsson, 1996, p. 24), or that we will experience an "agroforestry fibre revolution" as Wilson forecasts (1995, p. 13).

Summary

The technological developments that have taken place over the last couple of decades and will shape the future of the wood processing industries are mainly a response to declining raw material supplies, in particular the shortage of large diameterlogs. The sawnwood and plywood categories have reacted to shortages to some extent. Both have improved recovery rates and are able to handle smaller diameters today. However, in comparison to equipment used in industrial countries there is still a major gap.

Developments have been more pronounced in the wood-based panel categories. Not only has there been a rapid transformation from plywood to particleboard, but most processors have also switched to alternative resources. Thus, today Malaysia's MDF producers rely solely on rubberwood. In the future, it can be expected that some producers will rely on oil palm fibres or other non-wood fibres. However, the latter are available mainly seasonally incurring additional costs in logistics and storage.

The wood processing evolution that the Region has witnessed will continue over the next ten to fifteen years. As a result, the dependence on large-sized timber will decrease further, influencing traditional forest silviculture and other forestry practices. Secondary forests and plantations will become more attractive.

Moreover, the importance of reconstituted wood-panels will gain momentum in the Region with its growing middle class spending a significant amount of its income on furniture. Marketing strategies will play a significant role in reducing consumers' preferences for solid wood products and increasing the acceptability of panel products.

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