No abstract

Indonesia has abundant forest biomass resource, which should not be considered as a low economic value resource. This forest biomass resource can be converted into bioenergy through various technologies and it becomes one of sources in Indonesia's energy mix. This paper focuses on the wood processing mill residues, one type of forest biomass resources. Data were obtained from observation and survey at one of large private wood processing companies in Indonesia. An economic value of US$19.0 per ton wood residue would be created when the company sold its wood processing mill residues as fuelwoods. In contrast, using a conversion return approach, the economic value of wood residues increased to be about US$ 29.6 per ton wood residue when they were pelletized, an economic value increase of 56%. Sensitivity analysis further showed that the economic value of wood processing mill residues is more sensitive to changes in the price of wood pellets than to changes in the price of fuelwoods.

A non-isocyanate route of polyurethane synthesis based on polyol (xylitol, sorbitol, glycerol, and PG3), alkyl carbonate (DMC and DEC), and diamine (HMDA, EDA, and DETA) was conducted for wood impregnation through in-site polymerization. The structure and mass average molecular weight (Mw) of the polyurethanes were analyzed using FTIR, NMR, and SEC. According to the results, polyurethane synthesis by a two-pot method in water brought cyclic carbonate degradation. The distribution of Mw of the polyurethanes showed that the most satisfying polymer (4380 g/mol) was prepared without solvent. Polyurethanes synthesized in methanol have a higher Mw than that in distilled water. In the same solvent, the use of HMDA resulted in a polymer with higher Mw than that of EDA. One-step wood impregnation in a solvent gave unsatisfactory WPG (12.59–19.71%) and LC (50.36–62.80%). However, one-step impregnation without solvent gave a higher WPG (78.39–87.63%) and a lower LC (19.11–21.25%). It is not feasible to be applied industrially. The two-step impregnation gave WPG (14.89-30.73%) and LC (42.22–56.52%). Wood impregnation using methanol or ethanol as the solvent was more recommended than using an aqueous solution. However, the resistance against leaching needs improvement. Keywords: Alkyl carbonate, diamine, polyol, polyurethane, wood impregnation

Oil palm plantation is a very potential source of feedstock for biodiesel production in Indonesia. Its productivity is high in terms of biomass, such as fresh fruit bunch (FFB), trunk and frond. FFB can be processed into crude palm oil (CPO) and further into biodiesel. Currently, most CPO productions are exported even though a domestic demand for biodiesel is increased. The problem might be due to a low added value of biodiesel production from CPO/FFB. The objectives of this study were to estimate the potential production of biomass from oil palm plantation and calculate the economic value of FFB as feedstock for biodiesel. Data were obtained from observation and survey at one of large stated-owned oil palm plantation companies in Indonesia. The results showed that potential production of biomass were 42.10 tons/ha/year based on photosynthetical approach. Further, based on conversion return approach, economic value of FFB when processed into CPO was found about USD 121.82 per ton FFB and this value would decrease to USD 95.20 per ton FFB is processed into biodiesel. This indicates that the CPO production is economically more favorable than biodiesel production. If the price of CPO decreases by more than 15%, implying at least 13% decrease in biodiesel production cost; the expansion of FFB use as bioenergy would be expected as the economic value of FFB derived from biodiesel production would be higher than that obtained from CPO production.