scholarly journals Drying quality and colour of subfossil oak from central Serbia

2018 ◽  
pp. 157-172
Author(s):  
Marko Veizovic ◽  
Zdravko Popovic ◽  
Nebojsa Todorovic ◽  
Goran Milic
Keyword(s):  
Colour Change ◽  
Case Hardening ◽  
Drying Process ◽  
Oak Wood ◽  
Kiln Drying ◽  
Conventional Drying ◽  
Drying Conditions ◽  
Subfossil Wood ◽  
Drying Quality

The subject of this paper is the analysis of the quality of natural and conventional drying of subfossil oak wood. In addition to the drying quality, the colour of this material, as well as the effect of the drying process on colour change have been tested. The subfossil oak logs that were used in this experiment originate from the Morava River in Central Serbia. After sawing, timber was air-dried to about 20% moisture content (MC) followed by kiln-drying to 9.5% MC. By examining the quality of air-drying of the subfossil oak wood, a high presence of cracks was found, as well as the inaccuracy of humidity measurement using electric moisture meters. The stack for kiln-drying consisted of 24 boards, of which 4 were used for the monitoring of MC and MC distribution across the thickness of plank during drying. Drying quality was evaluated after the kiln-drying process. Although mild drying conditions during kiln-drying were applied, the gap as a measure of case-hardening had a value greater than usual for oak of same thickness. It was found that the drying process has no significant effect on the change in the colour of subfossil wood. The colour of the subfossil oak wood was significantly darker than the usual oak wood, and the colour difference between the central and the outer parts of the trunk of the subfossil oak was determined.

scholarly journals DESIGN OF KEMPLANG CRACKERS DRYER USING TRAY DRYER BY UTILIZING BIOMASS ENERGY

2021 ◽  
Vol 14 (1) ◽  
pp. 26-34
Author(s):  
Della Yusfita Sari ◽  
Mustain Zamhari ◽  
Robert Junaidi
Keyword(s):  
Heat Energy ◽  
Biomass Energy ◽  
Drying Rate ◽  
Drying Process ◽  
Air Velocity ◽  
Long Time ◽  
Conventional Drying ◽  
Coconut Shells ◽  
Drying Conditions

The drying process on kemplang crackers is one of the factors that determine the quality of the resulting product. Conventional drying has many disadvantages, namely fluctuating heat and poor hygiene that will affect product quality. So that kemplang crackers can be stored for a long time, it is necessary to reduce the water content of kemplang crackers. Drying kemplang crackers can use a drying rack with a biomass energy source from coconut shells. This study aims to design a tray dryer with biomass energy to obtain dryer performance based on the drying rate and to obtain a product that meets SNI No. 8272-2016. The treatments that were varied were set point temperatures of 55oC, 60oC, 65oC, and 70oC with mass variations of 50 gr, 100 gr, and 150 gr. The results showed that the optimum drying conditions at 70oC for 4 hours with an air velocity of 5.2 m/s2 obtained 9,84% moisture content in 50 gr kemplang crackers, 15.39% in 100 gr crackers and 19,2 in kemplang crackers 150 gr and a drying rate of 0,035028 kg/hour m2. The drying process requires 5,24 kg of dried coconut shell to produce heat energy of 95.358,81024 KJ with a by-product in the form of liquid smoke.

The Air-Kiln Drying Technology Research on Australian Eucalyptus regnans Board

2011 ◽  
Vol 393-395 ◽  
pp. 507-514
Author(s):  
Kai Meng Xu ◽  
Deng Yun Tu ◽  
Peng Xiang Peng ◽  
Qiong Guo ◽  
Hong Yun
Keyword(s):  
National Standards ◽  
Test Method ◽  
Eucalyptus Regnans ◽  
Kiln Drying ◽  
Drying Technology ◽  
Drying Properties ◽  
Visible Defect ◽  
Refractory Wood ◽  
Drying Quality

This paper researched on Australian Eucalyptus regnans drying properties by 100°C Test Method, also researched 25mm-thick boards dried by air-kiln drying schedule. The result indicated that the species belongs to refractory wood when drying, with checks and collapse defects that develop easily. In order to improve the drying quality, we adopted the method of first air-drying the moisture content (MC) to four different ranges and then kiln-drying. The two phrase air-kiln drying schedule concluded that the drying cycle of 25mm-thick Eucalyptus regnans board from 76.34% to 13.11% MC was 33.5 days, and the drying quality of visible defect met the requirement for the first level of the Chinese national standards.

scholarly journals The Effect of Drying Parameters on the Quality of Pork and Poultry-Pork Kabanosy Produced according to the Traditional Specialties Guaranteed Recipe

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Marta Chmiel ◽  
Lech Adamczak ◽  
Katarzyna Wrońska ◽  
Dorota Pietrzak ◽  
Tomasz Florowski
Keyword(s):  
Relative Humidity ◽  
Salt Content ◽  
Raw Material ◽  
Chemical Components ◽  
Drying Process ◽  
Final Yield ◽  
Drying Conditions ◽  
Drying Chamber ◽  
Selection Of

The aim of this study was to determine the effect of differentiated air relative humidity during the drying process on selected quality features of TSG (traditional specialties guaranteed) pork and poultry-pork kabanosy. After heat treatment and 24-hour cooling at 4–6°C, the products were placed in three chambers at 15°C with differentiated air relative humidity: 60, 70, and 80%, respectively. The drying process was carried out until all variants of kabanosy achieved the required final yield of the product (<68%). Color components, water activity and shear force, water, protein, fat, and salt content, and the TBARS indicator values were determined. The drying process might be shortened (~50%) by a reduction of humidity in the drying chamber from 80 to 60%. The changes in the content of chemical components in pork kabanosy compared to poultry-pork ones demonstrated the different dynamics of the drying of the two types of kabanosy and the need for the selection of optimum drying conditions relative to raw material composition.

scholarly journals Quality Assessment of Air-dried Teakwood Boards Using Moisture Content Gradients

2016 ◽  
Vol 24 (0) ◽  
Author(s):  
Djeison Cesar Batista ◽  
José Tarcísio da Silva Oliveira ◽  
Rená Porto Pizetta ◽  
Vinicius Munaldi Lube
Keyword(s):  
Moisture Content ◽  
Average Moisture Content ◽  
Drying Process ◽  
Air Drying ◽  
Kiln Drying ◽  
Moisture Meter ◽  
Environment Control ◽  
Moisture Content Gradient

ABSTRACT The determination of moisture content gradients is one of the most important steps for assessing the quality of wood drying. The general aim of this work was to study the quality of air-dried teakwood boards according to the gradients of moisture content in thickness and length. Six representative boards (40 × 180 × 2,300 mm) were sampled from a stack air-dried under shelter, divided into 30 equal parts in length and measured with a resistance moisture meter, resulting in four treatments: two depths (1/4 and 1/2 thickness) and two surfaces (inner and outer) of measurement. As main results, we can conclude that the air-drying quality can be considered good, mainly for two reasons: i) the average moisture content gradients in thickness were comparable to those reported in literature for kiln-drying of less thick boards; ii) the range of average moisture content among boards (2.5 p.p.) was satisfactory for a drying process carried out without environment control. Length moisture content gradient was completely different from that reported in literature, in which no board tops had smaller moisture content than the parts comprehended in between the tops.

scholarly journals Influence of steaming on drying quality and colour of beech timber

2015 ◽  
pp. 83-96
Author(s):  
Goran Milic ◽  
Nebojsa Todorovic ◽  
Ranko Popadic
Keyword(s):  
Moisture Content ◽  
Final Moisture Content ◽  
Case Hardening ◽  
Content Difference ◽  
Significant Difference ◽  
Conventional Drying ◽  
Drying Quality

This paper presents the results of an analysis of influence of the ?light? steaming process on conventional drying and colour of beech timber. A stack consisting of steamed and unsteamed boards was dried. Moisture content and moisture content profiles were recorded, and at the end of drying final moisture content, moisture content difference across thickness, case-hardening and colour were determinated. No statistically significant difference between steamed and unsteamed timber was established in any of the examined parameters (MC, ?MC, gap). The results indicate that equal (or even) better drying quality can be expected with steamed beech timber than with unsteamed timber, given the same drying schedule. Dry steamed timber was darker and more reddish than the unsteamed one. An imprecision of measurement by probes in the kiln was noticed in measuring steamed and unsteamed beech timber having a moisture content of between 7% and 15%, and a solution for overcoming this problem was given.

scholarly journals Effects of microwave pretreatment on drying of 50 mm-thickness Chinese fir lumber

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Xiang Weng ◽  
Yongdong Zhou ◽  
Zongying Fu ◽  
Xin Gao ◽  
Fan Zhou ◽  
...  
Keyword(s):  
Chinese Fir ◽  
Drying Process ◽  
Drying Time ◽  
Moisture Migration ◽  
Appearance Quality ◽  
Micro Cracks ◽  
Conventional Drying ◽  
Drying Behavior ◽  
Ray Parenchyma Cells

AbstractLow permeability of wood causes problems during drying of timber. This study evaluated the effects of microwave (MW) pretreatment on the conventional drying behavior and mechanical damages of Chinese fir lumber. MW pretreatment of lumber was performed at applied MW energy of 43 kWh/m3, and then, the samples were dried in a laboratory drying kiln. The results showed that the drying rate was effectively increased after MW pretreatment. The moisture content (MC) deviation in thickness and residual stress indexes of MW-pretreated samples were significantly decreased in comparison with the control samples, and the appearance quality of wood samples was not clearly affected by the MW pretreatment. Scanning electron microscope (SEM) micrographs demonstrated that pit membranes were damaged after MW pretreatment, and the micro-cracks in radial section as well as detachments between ray parenchyma cells and tracheids were also observed. Consequently, new pathways for moisture migration during drying process were formed after MW pretreatment, which contributed to the improved permeability of Chinese fir lumber and decreased drying time.

scholarly journals Study of Four Onion Varieties Drying Kinetics in an Oven and a Solar Greenhouse

2019 ◽  
Vol 8 (3) ◽  
pp. 59
Author(s):  
Ngoné Fall Beye ◽  
Nicolas Cyrille Ayessou ◽  
Cheikhou Kane ◽  
Mariame Niang Mbaye ◽  
Cheikh Talla ◽  
...  
Keyword(s):  
Lower Cost ◽  
Physicochemical Characterization ◽  
Drying Kinetics ◽  
Solar Drying ◽  
Drying Process ◽  
Allium Cepa L ◽  
Solar Greenhouse ◽  
Drying Conditions

Onion production (Allium cepa L.) in Senegal reached 390 000 tons in 2016. Due to post-harvest losses, annual demand (150 000 and 250 000 tons) is being met through imports. This work consists in proposing a drying process at a lower cost to overcome this dependence and preserve the quality of the product. The optimization of local onion varieties drying in an oven and in solar greenhouse, as well as the physicochemical characterization of the products were carried out. The moisture of fresh onion bulb varies between 85.56 &plusmn; 0.60 and 89.13 &plusmn; 0.69 (%). To obtain a moisture &pound; 8.89 &plusmn; 0.16 (%) ensuring stability, the optimal drying conditions in the oven are 60&deg; C / 6H (Galmi Violet) and 7H (Safari, Gandiol F1 and Orient F1). Under these conditions, the content of polyphenols in g equivalent of gallic acid / 100 g db increases (0.111 &plusmn; 0.0040 to 0.312 &plusmn; 0.0041 before drying, 0.546 g &plusmn; 0.0117 to 0.837 &plusmn; 0.0091 after drying). Optimum solar drying in a greenhouse is obtained between temperatures of 35 to 65&deg; C / 8H-9H. From a perspective of sustainable development, the perspective is the modeling of drying kinetics in a solar greenhouse.

scholarly journals Analysis of mechano-sorptive effect in oscillatory drying of beech timber

2016 ◽  
pp. 119-136
Author(s):  
Goran Milic ◽  
Nebojsa Todorovic
Keyword(s):  
Moisture Content ◽  
Software Tool ◽  
The Other ◽  
Drying Process ◽  
Surface Layers ◽  
Wood Moisture ◽  
Special Software ◽  
Conventional Drying ◽  
Cyclic Changes

The paper shows results of analysis of influences of oscillating parameters of drying on measuring wood moisture content in the kiln, rate and quality of drying. For this analysis, we used a conventional drying cycle, a cycle with oscillating equilibrium moisture content (EMC), and a cycle with oscillating temperatures. A special software tool was created for managing the oscillations. It was shown that oscillations of EMC and temperatures result in cyclic changes in wood MC, but also in the additional inaccuracies of MC measurements in the kiln. The drying process of the cycle with oscillating EMC lasted somewhat shorter than the other two cycles. Drying quality was the same or better in the cycles with oscillations as compared to the conventionally dried cycle, and the smaller tensions in the wood confirmed the activation of the additional mechano-sorptive effect during cyclic changes of MC in surface layers.

scholarly journals Drying of oak wood lamellas: Part 1. Analysis of the process in a dehumidification kiln

2021 ◽  
pp. 45-58
Author(s):  
Goran Milic ◽  
Nebojsa Todorovic ◽  
Marko Veizovic ◽  
Ranko Popadic
Keyword(s):  
Solid Wood ◽  
High Rate ◽  
Water Evaporation ◽  
Oak Wood ◽  
Wood Flooring ◽  
Conventional Drying ◽  
Higher Temperature ◽  
Short Time ◽  
Interesting Alternative ◽  
Drying Quality

The subject of this paper is to analyse the drying process of oak lamellas, which are the solid wood top layer of engineered wood flooring. The focus of the first part of the paper is on dehumidification kilns. Drying in a dehumidification kiln is an interesting alternative to conventional drying of thin solid oak wood with the aim of reaching high drying quality in a reasonable time. Drying tests were done in an industrial dehumidification kiln, and drying parameters were compared with the drying in the conventional kiln. Simultaneously, a drying test at a higher temperature was done in the programmable climate chamber. It was demonstrated that thin oak lamellas (approx. 5 mm thick) could be successfully dried in a dehumidification kiln in a relatively short time and with high drying quality. With the applied drying schedule (initial temperature of 36?C, final temperature of 46?C), the drying cycle will last 2 to 5 days, depending on the amount of wood and the initial MC. Due to the high rate of water evaporation and the inability of the kilns to remove it fast enough, the drying of lamellas in both dehumidification and conventional kilns takes place at a higher equilibrium moisture content than the set values.

scholarly journals DRYING OF RYE (LOLIUM MULTIFLORUM L.) IN FIXED BED WITH PARALLEL AIR FLOW

Engevista ◽  
2016 ◽  
Vol 18 (1) ◽  
pp. 11
Author(s):  
Akel Ferreira Kanaan ◽  
Janice Botelho Souza Hamm ◽  
Camila Gomes Flores ◽  
João Carlos Pinto Oliveira ◽  
André Ricardo Felkl de Almeida
Keyword(s):  
Lolium Multiflorum ◽  
Air Flow ◽  
Fixed Bed ◽  
Drying Process ◽  
Air Velocity ◽  
Physiological Characterization ◽  
Physiological Quality ◽  
Drying Conditions

This work aimed to study the drying of ryegrass seeds (Lolium multiflorum L.) in fixed bed dryer with parallel air flow. The study consisted of physical and physiological characterization of seeds, seed rewetting, study the desorption isotherms of rewetted seeds and the drying process  of the rewetted seeds under the following conditions: temperature from 40 to 60 ° C, air velocity 1.0 and 2.0 m/s and the height of the tray 0.005 and 0.01 m. The experimental data showed that the drying conditions applied to the seeds can significantly influence the moisture content and the physiological quality of the final product.

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