PHYSICO-MECHANICAL PROPERTIES OF SUPER-FAST DRIED OIL …

PHYSICO-MECHANICAL PROPERTIES OF SUPER-FAST DRIED OIL PALM

LUMBER AS THE CORE OF BLOCK BOARD

WONG ZHI SHAN

FH 2017 31

PHYSICO-MECHANICAL PROPERTIES OF SUPER-FAST DRIED OIL PALM LUMBER AS THE CORE OF BLOCK BOARD

By

WONG ZHI SHAN

A Project Report Submitted in Partial Fulfillment of the Requirements for the Degree of Bachelor of Wood Science Technology in the

Faculty of Forestry Universiti Putra Malaysia

2017

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DEDICATION

Special dedication to:

My awesome family members

(Wong Hon Kion, Pang Siew Li, Foo Qwee, Celynn Wong,

Wong Zhi Zhen, Wong Zhi Liang, Wong Zhi Shen and Wong Zhi Jeng)

My coursemates

(E Yee, Yuen Ling, Heather, Arini, Hafiz, Faiz, Rahmat, Waniey and Hani)

Known & Unknown, Oil Palm Tree, Hot Press Machine, Earth

For making me who I am now

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ABSTRACT

Super-Fast Drying is a new, efficient technology used to dry oil palm wood by

creating minimum drying defects. However, holed appearance on the lumber

deducts its economic value. Therefore, block board was suggested to increase

the value of super-fast dried lumber. The lumbers worked as the core of block

board and laminated with thin Keruing veneers as the surface layers. The

possibility of block board as the end product of super-fast dried lumbers was

investigated in this project by using high density and low density super-fast

dried lumbers. Besides, the physical and mechanical properties of the block

board were determined. In the beginning, the core lumbers were holed

according to optimum diameter and distance between two holes. Then, 2-step

drying was carried out, hot-press drying came first and high temperature kiln

drying came then. After one-week conditioning, the lumbers were then further

process by butt jointing two lumbers together between two veneers. The

sandwich structure was then hot-pressed to cure the resin. Two stoppers were

put on the sides to achieve target final thickness of block boards. After one-

week conditioning, block boards were cut for testing. The results confirmed the

availability of block board as the end product of super-fast dried lumbers. There

was significant difference between block board made with untreated oil palm

lumber and super-fast dried oil palm lumber as the core in MOE, while for

physical properties, there was different between both samples after 2-hour

immersion in water. Besides, the block boards made of super-fast dried

lumbers showed minimum drying defect.

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ABSTRAK

‘Super-fast drying’ merupakan satu teknologi baru yang digunakan untuk

mengeringkan kayu kelapa sawit dengan pantas dan menimbulkan kecacatan

pengeringan secara minimum. Akan tetapi, lubang yang digerudi atas papan

mengurangkan nilai ekonomi kayu tersebut. Oleh itu,papan blok dicadangkan

untuk menambahbaik penampilan papan ‘super-fast dried’. Matlamat kajian ini

ialah menghasilkan papan blok menggunakan papan ‘super-fast dried’

ketumpatan tinggi dan ketumpatan rendah. Ciri-ciri fizikal dan mekanikal

papan blok juga akan dikenalpasti. Pada mulanya, papan ‘super-fast dried’

akan dihasilkan melalui pengerudian lubang atas kayu dan seterusnya

menjalankan pengeringan 2-langkah. Langkah pertamanya dijalankan melalui

mesin penekan panas dan seterusnya melalui tanur pengeringan. Papan blok

diletakkan ke dalam ‘conditioning room’ selama seminggu. Selepas seminggu,

pembuatan papan blok dimulakan dengan merekat papan ‘super-fast dried’ di

tengah dua keping venir Keruing. Penyumbat diletakkan di sisi papan blok

sebelum penekanan panas untuk menentukan ketebalan akhir papan blok.

Selepas ‘conditioning’ selama seminggu, papan blok dipotong mengikut saiz

untuk menjalankkan ujian fizikal dan mekanikal. Pembuatan papan blok

adalah berjaya dalam kajian ini. Bagi ciri-ciri fizikal, papan blok ‘super-fast

dried’ dan papan blok tidak dirawat menunjukkan perbezaan yang ketara

selepas sampel direndam selama dua jam di dalam air. Bagi ciri-ciri mekanikal,

sampel menunjukkan perbezaan yang ketara pada modulus keanjalan. Selain

itu, papan blok yang menggunakan papan kelapa sawit berawat menunjukkan

kecacatan pengeringan yang minimum.

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ACKNOWLEDGEMENTS

First of all, I would like to express my deepest gratitude to my supervisor,

Assoc. Prof. Dr. Edi Suhaimi Bakar and my co-supervisor, Dr. Mojtaba Soltani

for their passion and patience in motivating and conducting me in this study.

Their guidance and advice have helped me to rethink, revise, learn and update

knowledge in research field as well as in wood science and technology.

Besides, I would like to deliver my sincere appreciation to my thesis

committees: Muhammad Nadzim bin Mohd Nazip, Mohd Rafsan bin Rais,

Mohd Hafiz bin Yunus, Muhamad Faiz bin Mohd Fauzi, Arini Madira Puteri binti

Daslizar and Chen Yuen Ling, for their helping hands, encouragement and

guidance during this study. Moreover, special thanks are given to the staffs of

Faculty of Forestry for their assistance and cooperation when carrying out my

experiment.

Furthermore, my sincere appreciation to everyone who supported and helped

me directly or indirectly throughout the project. Last but not least, I would like

to pay tribute to all the researchers for their hard works in any studies to make

this world better.

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APPROVAL SHEET

I certify that this research project entitled “Physico-Mechanical Properties of Super-Fast Dried Oil Palm Lumber as the Core of Block Board” by Wong Zhi Shan has been examined and approved as a partial fulfilment of the requirement for the degree of Bachelor of Wood Science Technology in the Faculty of Forestry, Universiti Putra Malaysia.

…………………………………………………….

Assoc. Prof. Dr. Edi Suhaimi Bakar

Faculty of Forestry

Universiti Putra Malaysia

(Supervisor)

………………………………………

Prof. Dr. Mohamed Zakaria Hussin

Dean

Faculty of Forestry

Universiti Putra Malaysia

Date: January 2017

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TABLE OF CONTENTS

Page DEDICATION ii ABSTRACT iii ABSTRAK iv ACKNOWLEDGEMENT v APPROVAL SHEET vi LIST OF TABLE ix LIST OF FIGURE x LIST OF ABBREVIATION xii CHAPTER 1 INTRODUCTION 1 1.1 Background 1 1.2 Problem Statement 3 1.3 Objectives 4 1.4 Justification 5 2 LITERATURE REVIEW 6 2.1 Availability of Oil Palm Wood 6 2.2 Anatomical Characteristics 7 2.3 Physical Properties 8 2.3.1 Density 8 2.3.2 Moisture Content 10 2.3.3 Dimensional Stability 11 2.4 Mechanical Properties 12 2.5 Drying of Oil Palm Wood 13 2.6 Super-Fast Drying Method 14 2.7 Block Board 17 2.8 Panels Made of Oil Palm Wood 17 3 MATERIAL AND METHODS 19 3.1 Materials 19 3.1.1 Oil Palm Lumber 19 3.1.2 Urea Formaldehyde 19 3.1.3 Veneers 20 3.2 Apparatus 21 3.3 Preparation of Super-Fast Dried Lumbers 21 3.4 Preparation of Untreated Oil Palm Lumbers 23

3.5 Block Board Making 24 3.6 Testing 28 3.6.1 Physical Testing 28 3.6.2 Mechanical Testing 30 3.7 Specific Modulus 31 3.8 Specific Density 32 3.9 Interpretation of Data 33 4 RESULTS AND DISCUSSION 34

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4.1 Summarization of Result 34 4.2 Physical Properties 35 4.2.1 Block Board with High Density Core 35 4.2.2 Block Board with Low Density Core 38 4.3 Mechanical Properties 40 4.3.1 Block Board with High Density Core 40 4.3.2 Block Board with Low Density Core 43 4.4 Observations 47 4.4.1 Fracture 47 4.4.2 Spring-back 48 4.4.3 Raised-grain 49 4.4.4 Bonding Properties of Layers and Core of 49

Block Boards 5 CONCLUSION AND RECOMMENDATIONS 51

5.1 Conclusion 51 5.2 Recommendations 51

REFERENCES 53

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LIST OF TABLES

Page

Table 4.1: Summarization of t-test results of block board 34

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LIST OF FIGURES

Page

Figure 2.1 : Cross-sectional of oil palm trunk 7

(Killmann & Lim,1985)

Figure 2.2 : Density variation within an oil palm stem 9

(Lim and Khoo, 1986)

Figure 2.3 : Distribution of moisture content in longitudinal and 10

transverse sections of oil palm stem (Bakar et al.,2013)

Figure 2.4 : Process of super-fast drying method 16

(Bakar, Soltani, Paridah, Choo, 2016)

Figure 3.1 : Pattern of polygon sawing 19

Figure 3.2 : Urea formaldehyde 20

Figure 3.3 : Keruing veneer 20

Figure 3.4 : Drill bit with diameter 7mm 21

Figure 3.5 : Pressing of oil palm lumber by using hot press machine 22

Figure 3.6 : Super-fast dried lumber (high density) 23

Figure 3.7 : Flow of super-fast drying method 23

Figure 3.8 : Irregular edges of super-fast dried lumber with burn mark 24

Figure 3.9 : Applying urea formaldehyde on butt jointed super-fast 25

dried lumbers

Figure 3.10 : Two 20mm-stoppers were placed on the sides of blocks 25

before pressing

Figure 3.11 : High-temperature-oven-drying lumbers (high density) 26

Figure 3.12 : Process of block board making 27

Figure 3.13 : The experimental design of study 27

Figure 3.14 : Cutting pattern for sample testing for block board made 28

of high-density super-fast dried lumber

Figure 3.15 : Samples for water absorption testing 29

Figure 3.16 : Three-point flexural test 31

Figure 4.1 : Mean value of water absorption of block board 36

(high density core)

Figure 4.2 : Mean value of thickness swelling of block board 37

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(high density core)

Figure 4.3 : Mean value of water absorption of block board 38

(low density core)

Figure 4.4 : Mean value of thickness swelling of block board 40

(low density core)

Figure 4.5 : Mean value of MOE of block board (high density core) 41

Figure 4.6 : Mean value of MOR of block board (high density core) 41

Figure 4.7 : Mean value of SMOE of block board (high density core) 42

Figure 4.8 : Mean value of SMOR of block board (high density core) 43

Figure 4.9 : Mean value of MOE of block board (low density core) 44

Figure 4.10 : Mean value of MOR of block board (low density core) 45

Figure 4.11 : Mean value of SMOE of block board (low density core) 45

Figure 4.12 : Mean value of SMOR of block board (low density core) 46

Figure 4.13 : Cracked on untreated block board at the edge-jointing area 47

Figure 4.14 : Fracture of fibres along the grain on untreated block board 48

Figure 4.15 : Edge of treated core 48

Figure 4.16 : Thicker thickness of block board after conditioning 49

Figure 4.17 : Fuzzy, raised-grain occurred on untreated low 49

density core

Figure 4.18 : Bonding condition after bending test for low density block 50

boards

Figure 4.19 : Bonding condition after bending test for high density block 50

boards

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LIST OF ABBREVIATION

MC Moisture Content

OPT Oil Palm Trunk

OPW Oil Palm Wood

OPL Oil Palm Lumber

MOE Modulus of Elasticity

MOR Modulus of Rupture

SMOE Specific Modulus of Elasticity

SMOR Specific Modulus of Rupture

UF Urea Formaldehyde

TS Thickness Swelling

WA Water Absorption

FB Flexural Bending

EN European Standard

SPSS Statistical Package for the Social Sciences

SFD Super-Fast Dried

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CHAPTER 1

INTRODUCTION

1.1 Background

Since year 1917, oil palm trees (Elaeis guineensis jacq.) that originated from

West Africa have been planted commercially in Malaysia for production of oil.

In 2014, Malaysia is covered by up to 5.3 million hectares of oil palm plantation

(Harun & Loh, n.d.). Nowadays, Malaysia has become the second largest of

producers and exporters of oil palm in the world (Where is palm oil grown?,

2016; Palm Oil Exports by Country,2016).

However, the extensive development in palm oil sector has created critical

environmental problem during the production chain. In 2012, 83 million tonnes

dry weight of oil palm biomass which including oil palm trunks, oil palm fronds,

empty fruit bunch, etc. was produced. It is estimated that the oil palm biomass

production will reach 100 million tonnes dry weight by year 2020 (Oil palm

biomass to increase to 100m tonnes a year by 2020, 2013). Moreover, National

Innovation Agency Malaysia stated that the availability of oil palm trunk (OPT)

biomass is estimated up to 15 million tonnes dry weight per year from 2015 to

2020 (Koay, 2014).

OPT is a lignocellulosic biomass exists in huge amount, but low in quality. It

has poor dimensional stability, bad machining properties, low strength and

susceptibility to biodegradable agents (Bakar et al., 2013). There are various

researches have been carried out such as impregnation and compression in

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order to enhance the quality of oil palm lumber (Choowang & Hiziroglu, 2015).

However, oil palm plywood mills used only 40% of OPT and 60% of OPT still

leftover in Malaysia. It is still underutilised by industry due to the poor

properties and difficulties in drying process. High cost and long-time are

needed, and yet the dried lumbers show severe defects (Dungani et al., 2013).

These challenges are caused by high density variation and high moisture

content (MC) variation from outer layer to core layer of OPT (Lim & Gan, 2005).

Bakar, Soltani, Paridah and Choo (2016) developed Super-fast drying method

which helps to solve the drying problems and improve the efficiency of drying

process. In this method, holes are formed on the oil palm lumbers according

to optimum diameter and optimum distance between two holes. After that, 2-

step drying is carried out to achieve target MC, which hot-press drying comes

first, kiln drying comes then. By using this method, inner part and outer part of

OPT can be dried within 3 hours and its quality is guaranteed. This effective

drying process can be the attraction to prompt the development of oil palm

lumber as the alternative of wood in industry. However, the holing surface

deducts the commercial value. Thus, block board is suggested as the end

product which the super-fast dried lumber is used as the core.

Block board is defined as the wood composite which consists of a central layer

(core) made up of solid wood strips which is stiffened and bound together by

glued, hot-pressed rotary cut veneers overlaid with grain perpendicular one to

another (Zanuttini & Cremonini, 2002). It is almost similar to plywood, while the

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difference is the thickness of the core layer. The examples of block board

application are furniture, backs of cabinet, and centre panels of framed door

(Laufenberg, Ayrilmis, & White, 2005).

There are few of basic criteria used for selection of the block board for

structural applications, for examples, strength of the block board, strength of

the glue adhesion, and dimensional stability of the board. It is expected that

good quality block boards can be produced by using super-fast dried lumber

as the core of block board and hardwood veneer as the surface layers (Bakar

et. al, 2016). Since Super-fast drying method is just established recently, there

is no information of block board made of super-fast dried lumber on its

mechanical and physical properties. Therefore, in this study, solid wood strips

will be replaced by high density and low density super-fast dried oil palm

lumber. The physical properties and mechanical properties will be determined

to find out the availability of the products for commercial use in the market.

1.2 Problem Statement

Forests in Malaysia are implemented with National Forest Policy (NFP) and

Sustainable Forest Management (SFM). Therefore, the production of logs from

natural forests reduced and supply is limited (National Timber Industry Policy

2009-2020, 2009).

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Oil palm biomass has been one of the serious environmental issues in

Malaysia. Most of them are being unused because of the poor machining

properties, physical properties and mechanical properties. Every year, the oil

palm mills produce up to 18 million OPT biomass (Harun & Loh, n.d.).

Therefore, the OPT resources are in a huge amount and ready to be utilised

by the industry.

.

Bakar et al. (2016) introduced Super-fast drying method which improve the

efficiency of drying and minimize the defects happened during drying process.

However, the appearance of the super-fast dried lumber is not pleasant to be

a final product due to the holes formed during the drying process. Therefore,

the surfaces of the dried lumber need to be embellished for commercialization.

The mechanical properties and physical properties of super-fast dried oil palm

lumber as the core of block board is chosen to be determined in this study.

This is because the basic properties of products such as strength and

dimensional stability haven’t been determined before.

1.3 Objectives

This study was aimed to produce high performance block board from super-

fast dried oil palm lumber as the core and laminated with hardwood veneer

which work as surface layer. The mechanical and physical properties of block

board with high density core and low density core were determined.

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1.4 Justification

Producing block board by using effective Super-fast drying method, higher

volume of oil palm trunk biomass can be utilized since industry can dry the oil

palm wood in an easier and more effective way (Bakar et al., 2016). Moreover,

the lamination of veneers on the top and the bottom of the core can conceal

the holed appearance of the super-fast dried lumber and shows presentable

product in the market. Furthermore, the strength and dimensional stability of

block board made of super-fast dried lumber can be determined to evaluate its

availability in market.

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