Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium

In Sarawak, Acacia mangium is the primary species used for commercial forest plantation to reduce timber dependency from the natural forest. The wood has adequate strength, quality and durability for appropriate utilization and end-use. However, the uneven distribution of moisture content and drying...

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Main Author:	Elia, Ambrose
Format:	Thesis
Language:	English English
Published:	2022
Subjects:	SD Forestry
Online Access:	http://ir.unimas.my/id/eprint/38420/5/Elia%20Ak%20Ambrose%20-%20cutted.pdf http://ir.unimas.my/id/eprint/38420/7/Elia%20Anak%20Ambrose%20ft.pdf
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spelling	my-unimas-ir.384202023-05-12T09:15:09Z Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium 2022-04-25 Elia, Ambrose SD Forestry In Sarawak, Acacia mangium is the primary species used for commercial forest plantation to reduce timber dependency from the natural forest. The wood has adequate strength, quality and durability for appropriate utilization and end-use. However, the uneven distribution of moisture content and drying defects are the primary problems in converting Acacia mangium wood into high-value products. The major cause of those problems is the presence of wet pockets in the dried wood. The objectives of this study were to (1) determine the untreated moisture content and the physical properties of seven and 10-year-old of A. mangium wood, (2) determine the effect of pre-treatments on the drying time, occurrence of wet pocket and drying defects in dried A. mangium boards, and (3) develop new drying schedules for seven and 10-year-old A. mangium board. Trees of seven and 10-year-old A. mangium were obtained from a plantation. The felled trees were rough sawn to 50 mm and 400 cm thick and long, respectively. Defects-free quarter and rift-sawn sample boards were selected and subsequently cut to a standard size of 27 mm (thickness) × 150 mm (width) × 690 mm (length). Three pre-treatments experimented were incision, forced air drying and pressure. The average basic wood density of 10-year-old Acacia mangium was significantly higher than seven-year-old A. mangium. The untreated moisture content of the seven-year-old is greater than the 10-year-old A. mangium. Results showed that pressure pre-treatment was the best for both seven and 10- year-old A. mangium. All sample boards treated with pressure did not show severe drying defects such as checks, collapse, and honeycombing. Mild schedule was recommended for both seven and 10-year-old A. mangium. Although the recommended schedule is not the fastest in terms of drying rate, it can reduce the occurrence of wet pocket and minimize the incidence of drying defects in both ages. The newly developed drying schedule for seven-year-old A. mangium indicate that kiln drying begins with an initial dry-bulb temperature of 45 °C, the wet-bulb depression 1.7 °C and the final dry bulb temperature of 70 °C. For 10-year-old A. mangium begin with an initial dry-bulb temperature of 48 °C, wet-bulb depression 4.0 °C and the final dry bulb temperature of 71 °C. Application of the new drying schedule on flat sawn sample boards succeed with no severe drying defects. The new drying schedule for 10-year-old A. mangium able to reduce the occurrence of wet pocket University Malaysia Sarawak 2022-04 Thesis http://ir.unimas.my/id/eprint/38420/ http://ir.unimas.my/id/eprint/38420/5/Elia%20Ak%20Ambrose%20-%20cutted.pdf text en public http://ir.unimas.my/id/eprint/38420/7/Elia%20Anak%20Ambrose%20ft.pdf text en validuser masters University Malaysia Sarawak Faculty of Resource Science and Technology
institution	Universiti Malaysia Sarawak
collection	UNIMAS Institutional Repository
language	English English
topic	SD Forestry
spellingShingle	SD Forestry Elia, Ambrose Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium
description	In Sarawak, Acacia mangium is the primary species used for commercial forest plantation to reduce timber dependency from the natural forest. The wood has adequate strength, quality and durability for appropriate utilization and end-use. However, the uneven distribution of moisture content and drying defects are the primary problems in converting Acacia mangium wood into high-value products. The major cause of those problems is the presence of wet pockets in the dried wood. The objectives of this study were to (1) determine the untreated moisture content and the physical properties of seven and 10-year-old of A. mangium wood, (2) determine the effect of pre-treatments on the drying time, occurrence of wet pocket and drying defects in dried A. mangium boards, and (3) develop new drying schedules for seven and 10-year-old A. mangium board. Trees of seven and 10-year-old A. mangium were obtained from a plantation. The felled trees were rough sawn to 50 mm and 400 cm thick and long, respectively. Defects-free quarter and rift-sawn sample boards were selected and subsequently cut to a standard size of 27 mm (thickness) × 150 mm (width) × 690 mm (length). Three pre-treatments experimented were incision, forced air drying and pressure. The average basic wood density of 10-year-old Acacia mangium was significantly higher than seven-year-old A. mangium. The untreated moisture content of the seven-year-old is greater than the 10-year-old A. mangium. Results showed that pressure pre-treatment was the best for both seven and 10- year-old A. mangium. All sample boards treated with pressure did not show severe drying defects such as checks, collapse, and honeycombing. Mild schedule was recommended for both seven and 10-year-old A. mangium. Although the recommended schedule is not the fastest in terms of drying rate, it can reduce the occurrence of wet pocket and minimize the incidence of drying defects in both ages. The newly developed drying schedule for seven-year-old A. mangium indicate that kiln drying begins with an initial dry-bulb temperature of 45 °C, the wet-bulb depression 1.7 °C and the final dry bulb temperature of 70 °C. For 10-year-old A. mangium begin with an initial dry-bulb temperature of 48 °C, wet-bulb depression 4.0 °C and the final dry bulb temperature of 71 °C. Application of the new drying schedule on flat sawn sample boards succeed with no severe drying defects. The new drying schedule for 10-year-old A. mangium able to reduce the occurrence of wet pocket
format	Thesis
qualification_level	Master's degree
author	Elia, Ambrose
author_facet	Elia, Ambrose
author_sort	Elia, Ambrose
title	Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium
title_short	Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium
title_full	Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium
title_fullStr	Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium
title_full_unstemmed	Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium
title_sort	drying characteristics variation in dry pre-treated seven and 10-year-old acacia mangium
granting_institution	University Malaysia Sarawak
granting_department	Faculty of Resource Science and Technology
publishDate	2022
url	http://ir.unimas.my/id/eprint/38420/5/Elia%20Ak%20Ambrose%20-%20cutted.pdf http://ir.unimas.my/id/eprint/38420/7/Elia%20Anak%20Ambrose%20ft.pdf
_version_	1783728501864529920

Drying Characteristics Variation in Dry Pre-treated Seven and 10-Year-old Acacia mangium

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