Palm oil is one the three major vegetable oils in the world. It can be harvested throughout a year only around the equator. In the mill operation to produce oil, more than 10 Tg (Mt) of unused biomass is obtained as business as usual. Since the palm oil mills are very large, more than a few tens Gg (thousand tones) of uniform unused biomass can be collected constantly throughout a year. Moreover, the replanting season of oil palm trees is arriving currently and a large amount of oil palm trunks shall be wasted. Recently, it was found that there exists a lot of glucose inside the trunks and that glucose syrup can be easily obtained by pressing them like sugarcane processing.

In a GLUE model, the surplus arable land considering land use competitions is calculated as follows. Biomass demand is calculated from population and food demand per capita. Biomass supply potential is calculated from land areas for biomass production and the biomass productivity of the land areas. Then, surplus arable land considering land use competitions is calculated from the biomass demand and the biomass supply potential.

The details of the calculation about land use competitions are as follows. First, animal food demand produced from cereal feed is calculated from animal food demand minus fish supply minus animal food supply from pasture. Cereal demand is calculated from the cereal feed demand plus cereal demand for vegetable food. The land demand for cereals is calculated from the cereal demand divided by cereal productivity. The land for energy crop production is calculated from the total land for cereal production minus the land demand for cereal production. If the total land for cereal production is smaller than the land demand for cereal production, food shortage occurs and the land for energy crop production is zero.

Consequently, in a GLUE model it is assumed that the highest priority in the land use competitions of arable land is the land use for vegetable food production. The next is the land use for feed production that is converted to animal food. The last is the land use for energy crops production. In order to enlarge the total calorie supply, it is assumed that priority is given to supply of vegetable food over supply of animal food.

Further information

The Japan Institute of Energy, “Biomass Yogo Jiten”, Ohmsha, 2004 (in Japanese)

7.13.1 Policy

New Energy Promotion Law (Jan. 2002) approves bioenergy as a "new energy", and supports its introduction. The council for energy in METI (Ministry of Economy, Trade and Industry) publishes the target values for “new energy” at 2010; thermal use of biomass, 3.08 million kL oil equivalent, and electricity production from biomass and wastes, 5.86 million kL oil equivalent. These values, however, have no duty.

The strategy for biomass utilization “Biomass Nippon Strategy” was published in cabinet (Dec. 2002). The target values at 2010 were revised (Mar. 2006); biofuel for transportation, 0.5 million kL oil equivalent, utilization rate of unutilized biomass, 25%, number of “Biomass Town”, 300 areas. Ministry of Agriculture, Forestry, and Fishery approves municipalities that utilize biomass based on the characteristics of the region as "Biomass Towns".

Forests and coal resources were in abundance and were sufficient to meet energy demands. However, as human creativity exceeded expectations, producing a more efficient energy technology based on coal and then on oil was needed.

World ultimate conventional oil reserves are estimated at 2000 billion barrels. The global daily consumption of oil equals 71.7 million barrels. It is estimated that around 1000 billion barrels have already been consumed and 1000 billion barrels of proven oil reserves are left in the world (Asifa and Muneer, 2007). The price of petrol and other fuels will rocket with potentially disastrous economic consequences unless people have moved to alternatives to fossil fuels. Increased use of biomass will extend the lifetime of diminishing crude oil supplies. For instance, Carpentieri et al. (2005) shows the important environmental advantages of biomass utilization in terms of reduction of natural resource depletion, although an improved impact assessment methodology may better highlight the advantages due to the biomass utilization.

The oil palm tree (Elaeis guineensis) originated from West Africa. It was first introduced to Malaysia as an ornamental plant. In 1917, the first commercial planting took place in Tennamaran Estate in Selangor, laying the foundations for the vast oil palm plantations and palm oil industry in Malaysia. Later in the 1960s, the government introduced land settlement schemes for planting oil palm as a means to eradicate poverty for the landless farmers and smallholders. Now the oil palm plantations in Malaysia are largely based on the estate management system and small holders scheme. Today, more than 4 million ha of land in Malaysia is under oil palm cultivation producing 16 million tons of palm oil in 2006.

Oil palm is a crop that bears both male and female flowers on the same tree. Each tree produces 12-20 bunches per year (normally referred as fresh fruit bunches, FFB) weighing between 10-20 kg with more than 1000 fruitlets per bunch. Each fruitlet is spherical or elongated in shape. Generally the fruitlet is dark purple or almost black and the colour turns to orange red when ripe. Each fruitlet consists of a hard kernel (seed) inside a shell (endocarp) which is surrounded by the fleshy mesocarp. The oil palm produces two kinds on oil; crude palm oil from the mesocarp, and palm kernel oil from the kernel or seed. The trunks of young and adult plants are wrapped in fronds which give them a rather rough appearance. The older trees have smoother trunks apart from the scars left by the fronds which have withered and fallen off.

Oil palm trees start to bear fruits after 3 years old. Their most economic life is between 5-15 years, although palm trees continue to bear fruits until 25-30 years old. After that they are too tall (up to 20 m in height), generally they are fallen down for replantation with new trees or new clones. In Malaysia, the trees planted are mainly the tenera variety, a hybrid between the dura and pisifera. The tenera variety yields about 4 to 5 tons of crude palm oil (CPO) per ha per year and about 1 ton of palm kernels. The oil palm is most efficient, requiring only 0.25 ha to produce one ton of oil in comparison to soybean, sunflower and rapeseed which need 2.15, 1.50 and 0.75 ha, respectively.

Firewood can be used with simple equipment, but the mode of combustion changes as shown below. Char combustion is 10-20% of the whole combustion.

Drying ^ dry-distillation ^ flame combustion ^ char combustion (~ 150°C, endothermic)

(250~400°C, endothermic) (main combustion) (solid combustion)

When air supply is in shortage, hazardous tar is produced in the dry-distillation stage. At the stage of flame combustion, CO and soot (carbon particles) are produced, and part of tar is converted into carcinogenic PAH by pyrolysis. To prevent these pollutant from getting in the flue gas shown in Fig.3.1.4, high temperature and oxygen content is to be maintained by using air amount a little bit in excess from stoichiometry.

For safe combustion of firewood, air ratio of 1.25-1.4 is usually employed. When the air ratio is too high, the flame is diluted, and the flame temperature is lowered, thus, supplying excess air as secondary air is recommended. A device to place combustion catalyst over the flame is available commercially, which aims at achievement of complete combustion even at the air ratio close to 1.0, but gas flow is deteriorated, and yearly exchange of the catalyst is needed.

[E] ^-cooker I heating

Fuel woods ^ stove—————— > [flue gas] —> (chimney)

ash pan ——>[ash] —^ fertilizer

Fig.3.1.4 Material — and energy-flow after stove in fire wood system *e1, *e 2^ *e 3— :energy supply from outside,

At the upper part of Fig.4 is shown the use of heat. For air conditioning, heat loss can be small, but for cooking, effective use of heat is not always easy because heat transfer to the pot is needed. Development of an apparatus that works as both cooking stove and room heater requires elaborate work.

Generally, the top part of the stove, where the highest temperature is available, is used for cooking. For hot water supply which does not need boiling, lower temperature part is assigned.

Further Information

Forestry and Forest Products Research Institute, Japan, Ed. (2006) : ”Shinrin ringyono shorai yosoku”, p.31, p.411 (in Japanese) .

H. Sano, H., J. Soc. Mec. Eng. (2005), 108(1045), pp.926-927. (in Japanese) .

Ogi, T. in ”Biomass Handbook”,Japan Institute of Energy Ed.,Ohm-sha,2002,p.5 and p.16 (in Japanese)

4.7.1 What is biodiesel production?

Compared with other biomass resources, oils and fats are high in heat capacity, and their majority is liquid at an ambient tempreture. Although these characteristics are preferable for automobile fuel, viscoelasticity (>30mm2/s at 40oC) and flash point (>300oC) are so high that it cannot be used without modification. Therefore, by traseseterifying triglyrides of the oils and

fats, its viscoelasticity and flash point are reduceed respectively down to 3~5mm2/s and 160oC which would be appropriate with cetane number of 50-60 to substitute for the diesel fuel. This fatty acid methyl seter is called biodiesel fuel (BDF).

4.7.2 Characteristics of biodiesel production

Biodiesel is low in SOx, dark smoke and particulate matters, compared with diesel. Therefore, its exhausted emission is relatively clean. Additionally, there exists an advantage to keep carbon balance on the earth due to its biomass-derived product. Furthermore, it contains oxygen as an ester to be 11% low in heat capacity. However, due to its lubricity and less dark smoke emission, biodiesel is almost comparable to diesel in practical engine performance.

The inventory analysis is a phase of life cycle assessment involving the compilation and quantification of inputs and outputs for a product throughout its life cycle within the boundary (product system) determined from the goal of the study.

Firstly, the practitioner of inventory analysis needs to collect the data related to manufacturing, use, and final disposal of a targeted product. These data are generally called “Foreground data” and they should be collected by the practitioner of LCA.

The next data to collect are the input-output data for production of raw materials used to produce the product (including primary or secondary material), and for generation of electricity needed to utilize the product, etc. These data are generally called “Background data”. It is difficult for the practitioner of LCA to collect the background data, and usually the background data is quoted from research papers or past LCA case studies. When LCA practitioner refers to some data, it is necessary to check the consistency because the emissions for the combustion of heavy oil or the electricity generation may be different from literature to literature. Relation of foreground data and background data is shown for Fig. 6.1.2.

Foreground Data (LCA Practitioner)

Background Data (Existing Database)

In an inventory analysis, the following two items may be controversial: “System boundary” and “Allocation”. System boundary determines which unit processes shall be included within the LCA. The selection of the system boundary must be consistent with the goal of the study and important process must not be excluded in the system boundary. When any of two or more products come from the same unit process, “Allocation” is required. Allocation means partitioning the input or output flows of a process or a product system between the products under study and other by-products. In general, the inputs and outputs are allocated based on the weight ratio of the products. However, when the market values of the products are quite different, the inputs and outputs might be allocated in a proportion that reflects economic value.

Sago palm (Metroxylon sagu) is characteristic to this region. It produces large amount of starch.

Sago palm production is distributed from Southeast Asia to Oceania. Brunei is

classified as sago district with Celebes Island and the Moluccas. This is the district where sago starch supplies several tens of per cent in the main starch supply.

Sago palm belongs to palm family, but is a unique angiosperm because starch can be obtained from its trunk. After 16 years from plantation, or 10 years under good conditions, it forms trunk with a diameter of 40-60 cm, and height of 12-15 m and stores high purity of starch inside in preparation for flowering and fruition. All of this starch is used for breeding, and the tree dies, leaving seeds behind. The tree is cut down just before flowering when the starch amount is the most, and the trunk is cut in the length less than 1 m. The trunk has a skin which is several centimeters thick. It is cut vertically, and the pith of starch which is held by the fibers inside is taken out. Starch is obtained by loosening the pith, washing it with water, and removing the fiber with a net, as precipitation in the water. In this way, 300-500 kg-wet (100-150 kg-dry) of starch is available form one mature tree.

The advantage of sago plantation is the easiness of the job and large amount of starch obtained with small labor. Sago palm can be cultivated with the peat soil, which most of the plant cannot grow with, and sago plantation does not deteriorates the soil. Sago is the most suitable plant for the seaside of the rainforest region.

Production of ethanol from sago starch is technically easy, but the self-supply rate of the region is very low, and production of starch for biofuel is not practical.

Further information

Sano, H.in ”Biomass Handbook”,Japan Institute of Energy Ed.,Ohm-sha,2002,p.37.(in Japanese) ”Baiomasu yogo jiten’h Japan Institute of Energy Ed.,2006,p.178.(in Japanese)

There are two propagation methods, i. e. Generative (seeding) and Vegetative propagation (cutting). For monoculer business, satisfactory planting widths are 2 x 2, 2.5 x 2.5 and 3 m x 3 m. This is equivalent to crop densities of 2,500, 1,600 and 1,111 plants/ha. However, plants propagated by cutting show a lower longevity and posses a lower drought and disease resistance than plants propagated by seeds. Only during its first two years does it need to be watered in the closing days of the dry season. Ploughing and planting are not needed regularly,

as this shrub has a life expectancy of approximately forty years. The use of pesticides and other polluting substances are not necessary, due to the pesticidal and fungicidal properties of the plant.

1 ha of jatropha plant normally will give yield to 2,250 kg of seeds (Fig 8.3.3 Jatropha fruits & seeds) and 750 kg of oil, hence the ratio of seed to oil is 3: 1. Seed oil can be extracted either hydraulically using a press or chemically using solvents, however, chemical extraction cannot be achieved on a small scale basis.