---
_id: '11792'
abstract:
- lang: eng
text: To facilitate the drying process and enhance the properties of oil palm wood,
oil palm boards were mechanically pre-dewatered and thermo-hygro-mechanically
(THM) densified. The thickness of the boards was reduced with compression ratios
of 40%, 60% and 75%. Since densified wood tends to recover from compression, especially
under humid conditions, this study examined the set-recovery and the hygroscopic
behavior of THM densified oil palm wood. The equilibrium moisture content (EMC),
differential swelling and swelling coefficient, linear swelling and shrinkage
as well as the differential swelling anisotropy were determined under climate
conditions with different relative humidity (RH) (20°C/35% RH, 20°C/65% RH and
20°C/85% RH). The maximum swelling was measured after water soaking and the remaining
set-recovery was evaluated after re-drying at 103°C. The EMC was reduced by the
THM process by around 20%. In the direction of compression (thickness), the densified
specimens show higher values for all analyzed swelling and shrinkage parameters
than the undensified specimens from the equivalent position within the trunk.
The maximum swelling in thickness of 22–38% during water soaking is mostly reversed
by shrinkage during re-drying and a comparably low remaining set-recovery of 3–8%
is measured at oven dry condition.
author:
- first_name: Nathan
full_name: Kölli, Nathan
id: '74242'
last_name: Kölli
- first_name: Katja
full_name: Frühwald-König, Katja
id: '26232'
last_name: Frühwald-König
- first_name: Martin
full_name: Hackel, Martin
id: '79798'
last_name: Hackel
citation:
ama: Kölli N, Frühwald-König K, Hackel M. Hygroscopic behavior of thermo-hygro-mechanical
(THM) densified oil palm sawn timber. Wood Material Science & Engineering.
Published online 2024:1-12. doi:10.1080/17480272.2024.2381100
apa: Kölli, N., Frühwald-König, K., & Hackel, M. (2024). Hygroscopic behavior
of thermo-hygro-mechanical (THM) densified oil palm sawn timber. Wood Material
Science & Engineering, 1–12. https://doi.org/10.1080/17480272.2024.2381100
bjps: Kölli N, Frühwald-König K and Hackel M (2024) Hygroscopic Behavior
of Thermo-Hygro-Mechanical (THM) Densified Oil Palm Sawn Timber. Wood Material
Science & Engineering 1–12.
chicago: Kölli, Nathan, Katja Frühwald-König, and Martin Hackel. “Hygroscopic Behavior
of Thermo-Hygro-Mechanical (THM) Densified Oil Palm Sawn Timber.” Wood Material
Science & Engineering, 2024, 1–12. https://doi.org/10.1080/17480272.2024.2381100.
chicago-de: 'Kölli, Nathan, Katja Frühwald-König und Martin Hackel. 2024. Hygroscopic
behavior of thermo-hygro-mechanical (THM) densified oil palm sawn timber. Wood
Material Science & Engineering: 1–12. doi:10.1080/17480272.2024.2381100,
.'
din1505-2-1: 'Kölli, Nathan ; Frühwald-König, Katja ; Hackel,
Martin: Hygroscopic behavior of thermo-hygro-mechanical (THM) densified
oil palm sawn timber. In: Wood Material Science & Engineering. London,
Taylor & Francis (2024), S. 1–12'
havard: N. Kölli, K. Frühwald-König, M. Hackel, Hygroscopic behavior of thermo-hygro-mechanical
(THM) densified oil palm sawn timber, Wood Material Science & Engineering.
(2024) 1–12.
ieee: 'N. Kölli, K. Frühwald-König, and M. Hackel, “Hygroscopic behavior of thermo-hygro-mechanical
(THM) densified oil palm sawn timber,” Wood Material Science & Engineering,
pp. 1–12, 2024, doi: 10.1080/17480272.2024.2381100.'
mla: Kölli, Nathan, et al. “Hygroscopic Behavior of Thermo-Hygro-Mechanical (THM)
Densified Oil Palm Sawn Timber.” Wood Material Science & Engineering,
2024, pp. 1–12, https://doi.org/10.1080/17480272.2024.2381100.
short: N. Kölli, K. Frühwald-König, M. Hackel, Wood Material Science & Engineering
(2024) 1–12.
ufg: 'Kölli, Nathan/Frühwald-König, Katja/Hackel, Martin: Hygroscopic behavior
of thermo-hygro-mechanical (THM) densified oil palm sawn timber, in: Wood Material
Science & Engineering (2024), S. 1–12.'
van: Kölli N, Frühwald-König K, Hackel M. Hygroscopic behavior of thermo-hygro-mechanical
(THM) densified oil palm sawn timber. Wood Material Science & Engineering.
2024;1–12.
date_created: 2024-07-27T05:38:16Z
date_updated: 2025-06-25T13:03:03Z
department:
- _id: DEP7018
- _id: DEP1309
doi: 10.1080/17480272.2024.2381100
external_id:
isi:
- '001274838600001'
isi: '1'
keyword:
- Densification
- set-recovery
- swelling and shrinkage
language:
- iso: eng
page: 1-12
place: London
publication: Wood Material Science & Engineering
publication_identifier:
eissn:
- 1748-0280
issn:
- 1748-0272
publication_status: published
publisher: Taylor & Francis
quality_controlled: '1'
status: public
title: Hygroscopic behavior of thermo-hygro-mechanical (THM) densified oil palm sawn
timber
type: scientific_journal_article
user_id: '83781'
year: '2024'
...
---
_id: '11793'
abstract:
- lang: eng
text: One obstacle to the industrial processing of oil palm wood is its nearly water-saturated
state in green condition and its high tendency to develop cell collapse during
kiln drying. This study analyzed mechanical dewatering by flat compression as
an alternative pre-drying method for wet oil palm sawn timber. In the process,
boards 700 mm long were compressed at ratios of 40% and 60% using a laboratory
press, which resulted in water extraction of the free water varying between 38–52%
and 60–73%, respectively. Since unperforated press plates were used, the water
could only escape over the crosscut and long edges. The extent to which the crosscut
and long edges were involved in dewatering was examined, and found to depend on
the position of the board in the trunk due to the different water permeability
conditions at the different heights. Permeability measurements, therefore, were
carried out on cylindrical specimens using a specifically designed testing device.
For the analysis of the hydrostatic pressure development in the boards, three
pressure transducers were installed at different distances to the crosscut at
half board thickness. The analysis of the recovery of compression showed, that
the boards recovered to a large extend immediately after compression.
author:
- first_name: Nathan
full_name: Kölli, Nathan
id: '74242'
last_name: Kölli
citation:
ama: Kölli N. Dewatering behavior of wet oil palm sawn timber during flat compression.
Wood Material Science & Engineering. Published online 2024:1-15. doi:10.1080/17480272.2024.2355545
apa: Kölli, N. (2024). Dewatering behavior of wet oil palm sawn timber during flat
compression. Wood Material Science & Engineering, 1–15. https://doi.org/10.1080/17480272.2024.2355545
bjps: Kölli N (2024) Dewatering Behavior of Wet Oil Palm Sawn Timber during
Flat Compression. Wood Material Science & Engineering 1–15.
chicago: Kölli, Nathan. “Dewatering Behavior of Wet Oil Palm Sawn Timber during
Flat Compression.” Wood Material Science & Engineering, 2024, 1–15.
https://doi.org/10.1080/17480272.2024.2355545.
chicago-de: 'Kölli, Nathan. 2024. Dewatering behavior of wet oil palm sawn timber
during flat compression. Wood Material Science & Engineering: 1–15.
doi:10.1080/17480272.2024.2355545,
.'
din1505-2-1: 'Kölli, Nathan: Dewatering
behavior of wet oil palm sawn timber during flat compression. In: Wood Material
Science & Engineering. London, Taylor & Francis (2024), S. 1–15'
havard: N. Kölli, Dewatering behavior of wet oil palm sawn timber during flat compression,
Wood Material Science & Engineering. (2024) 1–15.
ieee: 'N. Kölli, “Dewatering behavior of wet oil palm sawn timber during flat compression,”
Wood Material Science & Engineering, pp. 1–15, 2024, doi: 10.1080/17480272.2024.2355545.'
mla: Kölli, Nathan. “Dewatering Behavior of Wet Oil Palm Sawn Timber during Flat
Compression.” Wood Material Science & Engineering, 2024, pp. 1–15,
https://doi.org/10.1080/17480272.2024.2355545.
short: N. Kölli, Wood Material Science & Engineering (2024) 1–15.
ufg: 'Kölli, Nathan: Dewatering behavior of wet oil palm sawn timber during
flat compression, in: Wood Material Science & Engineering (2024),
S. 1–15.'
van: Kölli N. Dewatering behavior of wet oil palm sawn timber during flat compression.
Wood Material Science & Engineering. 2024;1–15.
date_created: 2024-07-27T05:39:13Z
date_updated: 2024-11-08T09:39:22Z
department:
- _id: DEP7018
- _id: DEP1309
doi: 10.1080/17480272.2024.2355545
keyword:
- Flat compression
- hydrostatic pressure
- mechanical dewatering
- water permeability
language:
- iso: eng
page: 1-15
place: London
publication: Wood Material Science & Engineering
publication_identifier:
eissn:
- 1748-0280
issn:
- 1748-0272
publication_status: published
publisher: Taylor & Francis
quality_controlled: '1'
status: public
title: Dewatering behavior of wet oil palm sawn timber during flat compression
type: scientific_journal_article
user_id: '26232'
year: '2024'
...
---
_id: '10593'
abstract:
- lang: eng
text: Due to shorter rotation cycles compared to other palm species, oil palm wood
has lower densities, a wider density range (150–600 kg/m3 dry), and a high moisture
content. The moisture content varies, reversely to the density, with the highest
values of up to 600% at the trunk core, especially at the top of the palm trunk.
Kiln drying material with such low density, very high moisture content and high
sugar and starch content is difficult and often produces drying defects such as
cell collapse, cracks, and mold. Mechanical dewatering of wet oil palm lumber
in an unheated double roller press reduces the water content and generates sugar-containing
pressed water (sap) that could be used as a source for biochemicals. The share
of mechanically removed water varied from 1 to >54% of the total water removed
from wet to dry state (at 20 °C, 65% rh). Center boards from the top of the trunk
had the highest dewatering rates while boards from the periphery at the bottom
of the trunk (high density, low water content) showed the lowest.
alternative_title:
- ByPalma 2021, Kuala Lumpur, Malaysia
author:
- first_name: Katja
full_name: Frühwald-König, Katja
id: '26232'
last_name: Frühwald-König
- first_name: Nathan
full_name: Kölli, Nathan
id: '74242'
last_name: Kölli
- first_name: Arno
full_name: Frühwald, Arno
id: '64961'
last_name: Frühwald
citation:
ama: 'Frühwald-König K, Kölli N, Frühwald A. Mechanical Dewatering of Wet Oil Palm
Lumber Prior to Press-Drying. In: Jawaid M, Midani M, Khiari R, eds. Proceedings
of 2nd World Conference on Byproducts of Palms and Their Applications . Springer
Nature Singapore; 2022. doi:https://doi.org/10.1007/978-981-19-6195-3_2'
apa: Frühwald-König, K., Kölli, N., & Frühwald, A. (2022). Mechanical Dewatering
of Wet Oil Palm Lumber Prior to Press-Drying. In M. Jawaid, M. Midani, & R.
Khiari (Eds.), Proceedings of 2nd World Conference on Byproducts of Palms
and Their Applications . Springer Nature Singapore. https://doi.org/10.1007/978-981-19-6195-3_2
bjps: 'Frühwald-König K, Kölli N and Frühwald A (2022) Mechanical Dewatering
of Wet Oil Palm Lumber Prior to Press-Drying. In Jawaid M, Midani M and Khiari
R (eds), Proceedings of 2nd World Conference on Byproducts of Palms and Their
Applications . Singapore: Springer Nature Singapore.'
chicago: 'Frühwald-König, Katja, Nathan Kölli, and Arno Frühwald. “Mechanical Dewatering
of Wet Oil Palm Lumber Prior to Press-Drying.” In Proceedings of 2nd World
Conference on Byproducts of Palms and Their Applications , edited by Mohammad
Jawaid, Mohamad Midani, and Ramzi Khiari. Singapore: Springer Nature Singapore,
2022. https://doi.org/10.1007/978-981-19-6195-3_2.'
chicago-de: 'Frühwald-König, Katja, Nathan Kölli und Arno Frühwald. 2022. Mechanical
Dewatering of Wet Oil Palm Lumber Prior to Press-Drying. In: Proceedings of
2nd World Conference on Byproducts of Palms and Their Applications , hg. von
Mohammad Jawaid, Mohamad Midani, und Ramzi Khiari. Singapore: Springer Nature
Singapore. doi:https://doi.org/10.1007/978-981-19-6195-3_2,
.'
din1505-2-1: 'Frühwald-König, Katja
; Kölli, Nathan ; Frühwald,
Arno: Mechanical Dewatering of Wet Oil Palm Lumber Prior to Press-Drying.
In: Jawaid, M. ; Midani,
M. ; Khiari, R. (Hrsg.):
Proceedings of 2nd World Conference on Byproducts of Palms and Their Applications
. Singapore : Springer Nature Singapore, 2022'
havard: 'K. Frühwald-König, N. Kölli, A. Frühwald, Mechanical Dewatering of Wet
Oil Palm Lumber Prior to Press-Drying, in: M. Jawaid, M. Midani, R. Khiari (Eds.), Proceedings
of 2nd World Conference on Byproducts of Palms and Their Applications , Springer
Nature Singapore, Singapore, 2022.'
ieee: 'K. Frühwald-König, N. Kölli, and A. Frühwald, “Mechanical Dewatering of Wet
Oil Palm Lumber Prior to Press-Drying,” in Proceedings of 2nd World Conference
on Byproducts of Palms and Their Applications , M. Jawaid, M. Midani, and
R. Khiari, Eds. Singapore: Springer Nature Singapore, 2022. doi: https://doi.org/10.1007/978-981-19-6195-3_2.'
mla: Frühwald-König, Katja, et al. “Mechanical Dewatering of Wet Oil Palm Lumber
Prior to Press-Drying.” Proceedings of 2nd World Conference on Byproducts
of Palms and Their Applications , edited by Mohammad Jawaid et al., Springer
Nature Singapore, 2022, https://doi.org/10.1007/978-981-19-6195-3_2.
short: 'K. Frühwald-König, N. Kölli, A. Frühwald, in: M. Jawaid, M. Midani, R. Khiari
(Eds.), Proceedings of 2nd World Conference on Byproducts of Palms and Their
Applications , Springer Nature Singapore, Singapore, 2022.'
ufg: 'Frühwald-König, Katja/Kölli, Nathan/Frühwald, Arno: Mechanical Dewatering
of Wet Oil Palm Lumber Prior to Press-Drying, in: Jawaid, Mohammad/Midani,
Mohamad/Khiari, Ramzi (Hgg.): Proceedings of 2nd World Conference on Byproducts
of Palms and Their Applications , Singapore 2022.'
van: 'Frühwald-König K, Kölli N, Frühwald A. Mechanical Dewatering of Wet Oil Palm
Lumber Prior to Press-Drying. In: Jawaid M, Midani M, Khiari R, editors. Proceedings
of 2nd World Conference on Byproducts of Palms and Their Applications . Singapore:
Springer Nature Singapore; 2022.'
conference:
end_date: 2021-09-30
location: Kuala Lumpur, Malaysia
name: '2nd World Conference on Byproducts of Palms and Their Applications '
start_date: 2021-09-28
date_created: 2023-10-26T07:41:34Z
date_updated: 2023-10-30T15:18:42Z
department:
- _id: DEP7018
- _id: DEP1309
doi: https://doi.org/10.1007/978-981-19-6195-3_2
editor:
- first_name: Mohammad
full_name: Jawaid, Mohammad
last_name: Jawaid
- first_name: Mohamad
full_name: Midani, Mohamad
last_name: Midani
- first_name: Ramzi
full_name: Khiari, Ramzi
last_name: Khiari
language:
- iso: eng
place: Singapore
publication: ' Proceedings of 2nd World Conference on Byproducts of Palms and Their
Applications '
publication_identifier:
eisbn:
- '978-981-19-6195-3 '
isbn:
- '978-981-19-6194-6 '
issn:
- 2662-3161
publication_status: published
publisher: Springer Nature Singapore
status: public
title: Mechanical Dewatering of Wet Oil Palm Lumber Prior to Press-Drying
type: book_chapter
user_id: '83781'
year: '2022'
...
---
_id: '6945'
abstract:
- lang: eng
text: 'Sustainable use of renewable raw materials is an important issue of policy
and industry. Wood prices are rising because of increasing market demand while
simultaneously forests are challenged through conservation issues, deforestation
and hazards. The main reasons for deforestation are agriculture, infrastructure
and wood harvesting. Oil palm plantations stock on former tropical forest land
and cover some 25 Mio ha worldwide. They are replanted every 25 years due to reduced
productivity. Using the available wooden trunk material of the cleared plantation
not only makes sense in ecological terms but is also a big chance for economy
and trade. Research over the last 30 years has led to several ideas in the use
for products. The biggest challenge is the anatomical structure of palm wood which
is different to coniferous or broadleaf trees. Hard vascular bundles are embedded
in low-density parenchyma storage tissue with high moisture content. The soft
and sponge-like parenchyma tissue can be compressed easily and a significant share
of the water (mc up to 600 % based on dry wood) can be squeezed out. Through press
drying, the volume of the parenchyma can be reduced and the wood density increases.
Wood strength and stiffness are related to its density and can be improved by
densification. TH OWL developed a four-step densification process for oil palm
boards. Oil palm lumber was produced from oil palm trunks in a sawmill and then
densified under defined conditions. The densification process includes (1) compression
to remove a certain percentage of the palm sap, (2) plastification under heat
and moisture to soften the wood, (3) hot compression to achieve the densification
and remove more water, and (4) press-drying to dry and harden the material. A
future perspective on how the laboratory tests could be scaled up to an industrial
application with a possible machinery set-up is presented. '
author:
- first_name: Nathan
full_name: Kölli, Nathan
id: '74242'
last_name: Kölli
citation:
ama: 'Kölli N. Densification and Press-Drying of Wet Oil Palm Lumber. In: Young TM,
Petutschnigg A, eds. 6th International Conference on Process Technologies
for the Forest and Biobased Products Industries PTF BPI 2021 . ; 2021.'
apa: Kölli, N. (2021). Densification and Press-Drying of Wet Oil Palm Lumber. In
T. M. Young & A. Petutschnigg (Eds.), 6th International Conference on
Process Technologies for the Forest and Biobased Products Industries PTF BPI
2021 .
bjps: Kölli N (2021) Densification and Press-Drying of Wet Oil Palm Lumber.
In Young TM and Petutschnigg A (eds), 6th International Conference on Process
Technologies for the Forest and Biobased Products Industries PTF BPI 2021 .
chicago: Kölli, Nathan. “Densification and Press-Drying of Wet Oil Palm Lumber.”
In 6th International Conference on Process Technologies for the Forest and
Biobased Products Industries PTF BPI 2021 , edited by Timothy M. Young and
Alexander Petutschnigg, 2021.
chicago-de: 'Kölli, Nathan. 2021. Densification and Press-Drying of Wet Oil Palm
Lumber. In: 6th International Conference on Process Technologies for the Forest
and Biobased Products Industries PTF BPI 2021 , hg. von Timothy M. Young und
Alexander Petutschnigg.'
din1505-2-1: 'Kölli, Nathan: Densification
and Press-Drying of Wet Oil Palm Lumber. In: Young
, T. M. ; Petutschnigg, A.
(Hrsg.): 6th International Conference on Process Technologies for the Forest
and Biobased Products Industries PTF BPI 2021 , 2021'
havard: 'N. Kölli, Densification and Press-Drying of Wet Oil Palm Lumber, in: T.M.
Young , A. Petutschnigg (Eds.), 6th International Conference on Process Technologies
for the Forest and Biobased Products Industries PTF BPI 2021 , 2021.'
ieee: N. Kölli, “Densification and Press-Drying of Wet Oil Palm Lumber,” in 6th
International Conference on Process Technologies for the Forest and Biobased
Products Industries PTF BPI 2021 , St. Simons Island, Georgia / USA, 2021.
mla: Kölli, Nathan. “Densification and Press-Drying of Wet Oil Palm Lumber.” 6th
International Conference on Process Technologies for the Forest and Biobased
Products Industries PTF BPI 2021 , edited by Timothy M. Young and Alexander Petutschnigg,
2021.
short: 'N. Kölli, in: T.M. Young , A. Petutschnigg (Eds.), 6th International Conference
on Process Technologies for the Forest and Biobased Products Industries PTF
BPI 2021 , 2021.'
ufg: 'Kölli, Nathan: Densification and Press-Drying of Wet Oil Palm Lumber,
in: Young , Timothy M./Petutschnigg, Alexander (Hgg.): 6th International
Conference on Process Technologies for the Forest and Biobased Products Industries
PTF BPI 2021 , o. O. 2021.'
van: 'Kölli N. Densification and Press-Drying of Wet Oil Palm Lumber. In: Young TM,
Petutschnigg A, editors. 6th International Conference on Process Technologies
for the Forest and Biobased Products Industries PTF BPI 2021 . 2021.'
conference:
end_date: 2021-11-03
location: St. Simons Island, Georgia / USA
name: PTF BPI 2021 (Process Technologies for the Forest & Biobased Product Industries)
start_date: 2021-11-01
date_created: 2022-01-06T11:43:06Z
date_updated: 2023-10-30T15:20:10Z
department:
- _id: DEP7018
- _id: DEP1309
editor:
- first_name: 'Timothy M. '
full_name: 'Young , Timothy M. '
last_name: 'Young '
- first_name: 'Alexander '
full_name: 'Petutschnigg, Alexander '
last_name: Petutschnigg
keyword:
- Oil Palm Wood
- Densification
- Drying
language:
- iso: eng
publication: '6th International Conference on Process Technologies for the Forest and
Biobased Products Industries PTF BPI 2021 '
publication_status: published
status: public
title: Densification and Press-Drying of Wet Oil Palm Lumber
type: conference
user_id: '83781'
year: '2021'
...