scholarly journals Drying behaviour observations for wood chips of grade EN14961

2021 ◽  
Vol 11 (4) ◽  
pp. 151-156
Author(s):  
Baibhaw Kumar ◽  
L. Gábor Szepesi ◽  
Zoltán Szamosi
Keyword(s):  
Renewable Energy ◽  
Moisture Content ◽  
Removal Rate ◽  
Wood Chip ◽  
Wood Chips ◽  
Moisture Removal ◽  
Solar Drying ◽  
Sun Drying ◽  
Solid Biofuels ◽  
Drying Behaviour

Solid biofuels such as woodchips have always been a significant source of fuel in the field of renewable energy. However, the drying of wood chips has been a challenge in preparing biofuels and other applications. The moisture content of below 25% in the wood chips of grade EN 14961 is considered the premium wood chip material. Solar drying emerged as a leading solution for the drying of wood chips. The paper investigates the comparison of moisture removal rate using a natural convective solar dryer compared to open sun drying developed at Miskolc, Hungary (48°06'15.0"N 20°47'30.0"E).

scholarly journals Effect of Pads and Thickness of Paddy on Moisture Removal under Sun Drying

2021 ◽  
Author(s):  
A. Narmilan ◽  
G. Niroash ◽  
M.I.M. Mowjood ◽  
A.T.A. Akram
Keyword(s):  
Sri Lanka ◽  
Moisture Content ◽  
Removal Rate ◽  
Initial Moisture Content ◽  
Storage Period ◽  
Moisture Removal ◽  
Drying Time ◽  
Sun Drying ◽  
Regular Time ◽  
Paddy Farmers

Background: Sun drying is a popular post-harvest operation to maintain rice quality during the storage period. Farmers use different pads and thicknesses for sun drying of paddy in Ampara district, Sri Lanka. A study was conducted to evaluate the suitability and effectiveness of the drying pad and thickness as practiced by local paddy farmers during the sun drying process.Methods: The grain with an initial moisture content of 28% (dry basis) was sun dried with four types of drying pads and five levels of thickness of grain. This experiment was conducted between 8.30 am and 4.30 pm at the South Eastern University of Sri Lanka in August 2020. The moisture contents of the grain were measured at regular time intervals.Result: It was found that the duration of drying of paddy from 28% to 13% moisture content on a dry basis was 300 to 540 minutes depending upon the drying pad and thickness. The tarpaulin is reasonable at shallow thickness with less time to reach the necessary moisture level than other drying pads. Black polythene and fertilizer bag can be utilized for sun drying of paddy at 4 cm thickness with 130 minutes. It was found that with an increase in the thickness of paddy from 0.5 cm to 4 cm, the drying time increases. A statistically significant interaction was obtained between drying pads and thickness level on moisture removal of paddy. Therefore, the moisture removal rate differs with the drying pad and thickness of the paddy under open sun drying.

scholarly journals Wood Chip Drying through the Using of a Mobile Rotary Dryer

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1590 ◽  
Author(s):  
Angelo Del Giudice ◽  
Andrea Acampora ◽  
Enrico Santangelo ◽  
Luigi Pari ◽  
Simone Bergonzoli ◽  
...  
Keyword(s):  
Moisture Content ◽  
Power Plants ◽  
Black Locust ◽  
Thermal Power ◽  
Initial Moisture Content ◽  
Wood Chip ◽  
Wood Chips ◽  
Cocurrent Flow ◽  
Drying Process ◽  
Rotary Dryer

Drying is a critical point for the exploitation of biomass for energy production. High moisture content negatively affects the efficiency of power generation in combustion and gasification systems. Different types of dryers are available however; it is known that rotary dryers have low cost of maintenance and consume 15% and 30% less in terms of specific energy. The study analyzed the drying process of woody residues using a new prototype of mobile rotary dryer cocurrent flow. Woodchip of poplar (Populus spp.), black locust (Robinia pseudoacacia L.), and grapevine (Vitis vinifera L.) pruning were dried in a rotary drier. The drying cycle lasted 8 h for poplar, 6 h for black locust, and 6 h for pruning of grapevine. The initial biomass had a moisture content of around 50% for the poplar and around 30% for grapevine and black locust. The study showed that some characteristics of the biomass (e.g., initial moisture content, particle size distribution, bulk density) influence the technical parameters (i.e., airflow temperature, rate, and speed) of the drying process and, hence, the energy demand. At the end of the drying process, 17% of water was removed for poplar wood chips and 31% for grapevine and black locust wood chips. To achieve this, result the three-biomass required 1.61 (poplar), 0.86 (grapevine), and 1.12 MJ kgdry solids−1 (black locust), with an efficiency of thermal drying (η) respectively of 37%, 12%, and 27%. In the future, the results obtained suggest an increase in the efficiency of the thermal insulation of the mobile dryer, and the application of the mobile dryer in a small farm, for the recovery of exhaust gases from thermal power plants.

scholarly journals Effects of microwave irradiation on the moisture content of various wood chip fractions obtained from different tree species

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Monika Aniszewska ◽  
Krzysztof Słowiński ◽  
Ewa Tulska ◽  
Witold Zychowicz
Keyword(s):  
Moisture Content ◽  
Microwave Irradiation ◽  
Microwave Power ◽  
Irradiation Time ◽  
Initial Moisture Content ◽  
Radiant Energy ◽  
Wood Chip ◽  
Wood Chips ◽  
Chip Size ◽  
Drying Rates

AbstractThe paper proposes the use of microwave irradiation to lower the initial moisture content of wood chips. The study involved willow and fir chips fractionated by means of a sieve separator and unfractionated ash chips. The wood chips were exposed to a constant microwave power of 800 W for 30 s, 60 s, 120 s and 180 s. The chips were weighed before and after irradiation to measure loss of moisture. It was found that the decline in moisture content increased with wood chip size for a given irradiation time and microwave power. The initial moisture content of wood chips was not found to significantly affect loss of moisture as the drying rates of wood chips with higher and lower moisture content exposed to microwaves were not statistically different. The results showed that irradiation intensity increased with the time of exposure to microwaves and unit radiant energy per unit of evaporated moisture decreased with increasing wood chip size in the 3.15–31.50 mm range.

scholarly journals Electrical Capacitance Characteristics of Wood Chips at Low Frequency Ranges: A Cheap Tool for Quality Assessment

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3494
Author(s):  
Jakub Lev ◽  
Václav Křepčík ◽  
Egidijus Šarauskis ◽  
František Kumhála
Keyword(s):  
Moisture Content ◽  
Linear Models ◽  
Economic Value ◽  
Wood Chip ◽  
Principal Component ◽  
Dissipation Factor ◽  
Industrial Applications ◽  
Wood Chips ◽  
Electrical Capacitance ◽  
Low Frequencies

Moisture content is one of the most important parameters related to the quality of wood chips that affects both the calorific and economic value of fuel chips. For industrial applications, moisture content needs to be detected quickly. For this purpose, various indirect moisture content measurement methods (e.g., capacitance, NIR, microwave, ECT, X-ray CT, and nuclear MR) have been investigated with different results in the past. Nevertheless, determining wood chip moisture content in real time is still a challenge. The main aim of this article was therefore to analyze the dielectric properties of wood chips at low frequencies (10 kHz–5 MHz) and to examine the possibility of using these properties to predict wood chip moisture content and porosity. A container-type probe was developed for this purpose. The electrical capacitance and dissipation factor of wood chips with different moisture content was measured by an LCR meter at 10 kHz, 50 kHz, 100 kHz, 500 kHz, 1 MHz, and 5 MHz frequencies. Wood chip porosity was also measured using a gas displacement method. Linear models for moisture content and porosity prediction were determined by backward stepwise linear regression. Mathematical model was developed to better understand the physical relationships between moisture content, porosity, and electrical capacitance. These models were able to predict the moisture content of observed quantities of wood chips with the required accuracy (R2 = 0.9−0.99). This finding opens another path to measuring the moisture content and porosity of wood chips in a relatively cheap and fast way and with adequate precision. In addition, principal component analysis showed that it is also possible to distinguish between individual wood chip fraction sizes from the information obtained.

scholarly journals Drying characteristics and prediction of best fitted drying model for coriander leaves

2021 ◽  
pp. 243-251
Author(s):  
Sanjay Kumar Singh ◽  
Samsher ◽  
B.R. Singh ◽  
R.S. Senger ◽  
Pankaj Kumar ◽  
...  
Keyword(s):  
Removal Rate ◽  
Drying Methods ◽  
Moisture Removal ◽  
Drying Time ◽  
Sun Drying ◽  
Potassium Metabisulphite ◽  
Solar Greenhouse ◽  
Drying Models ◽  
Drying Model ◽  
Coriander Leaves

Drying experiments were conducted on coriander leaves as affected by drying methods (solar greenhouse drying and open sun drying), pretreatments (dipping in a solution of magnesium chloride + sodium bicarbonate + potassium metabisulphite, boiled water blanching containing sodium metabisulphite, and untreated), and loading densities (2.0, 2.5 and 3.0 kg/m2). Validity of three commonly used drying models were examined to predict the most suitable drying model for coriander leaves. The increased drying temperature under solar greenhouse dryer (42°C) increases the amount of moisture removal from the coriander leaves and reduces the drying time by increasing the drying rate as compared to open sun drying (29°C), at all the selected levels of pretreatments and loading densities. Chemically treated coriander leaves dehydrated under a solar greenhouse dryer required less drying time than other treated leaves and dried leaves. Nevertheless, drying methods and loading densities had significant effects, while treatment effects were marginal. It was found that reduction of moisture and moisture removal rate per unit time occurred mostly in the falling rate period except some accelerated removal of moisture at the beginning up to 150 minutes. Page's model was found most appropriate for drying coriander leaves among the selected models.

scholarly journals Studies of the Combined Modes of Microwave Grain Drying

2018 ◽  
Vol 12 (6) ◽  
pp. 25-30
Author(s):  
Sergey A. Pavlov ◽  
Igor A. Pekhalsky ◽  
Nikolay G. Nikolay G. Kynev
Keyword(s):  
Moisture Content ◽  
Microwave Pulse ◽  
Raw Materials ◽  
Removal Rate ◽  
Pause Duration ◽  
Microwave Drying ◽  
Flow Density ◽  
Moisture Removal ◽  
Moisture Movement ◽  
Vegetable Raw Materials

Abstract. To ensure the high quality of the materials being dried, one of the most promising ways to dehydrate vegetable raw materials is drying under the action of electromagnetic radiation (microwave drying). Microwave drying is widely used in various industries, in particular, in the food and woodworking industries. (Research purpose) Calculation of the microwave pulse and pause duration; their experimental determination, as well as the determination of the moisture removal rate at the pulse moment and the depth of pulse penetration into the layer. (Materials and methods) When drying in a microwave field, the gradient of moisture content in the material prevents the moisture movement towards the surface, internal cracks can be formed as well. Therefore, the combined methods of drying can yield the best results. The pulse duration has been calculated by the permissible increment of the grain temperature, the pause duration has been determined by assuming that during the pulse, moisture from the caryopsis kernel is pushed out and cooled under isothermal conditions by an air flow. (Results and discussion) It has been confirmed that at a microwave pulse energy duration of 4, 6, and 10 s, the speed of blow-off and blowdown of the layer with external air was 0.5 m per second. When grain is cooled by natural convection, the pulse time is 10 s, the pause time is 1, 2, 3, and 5 min. For the blow-off mode, the pulse exposure time was 6 and 10 s, that of blow-off - 0.5, 1.0, and 1.5 minutes. The maximum duration of the microwave pulse was determined by the flow density of allowable grain heating and the fraction of heat required for the evaporation of moisture when heated to 20-25 degrees. (Conclusions) The pause duration is determined by the grain cooling time to the temperature preceding the pulse. It has been experimentally established that the calculated values of the pulse and pause duration with an accuracy of 15 percent for grain with a moisture content of 20-24 percent at a microwave flow density of 0.7 kilowatts per square meter, at a depth of the microwave energy penetration into the grain by 70 percent, do not exceed 20-22 mm, and the moisture removal rate is 0.1-0.15 percent.

scholarly journals Water Resistance of Torrefied Wood Pellets Prepared by Different Methods

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1618
Author(s):  
Takahiro Yoshida ◽  
Katsushi Kuroda ◽  
Daisuke Kamikawa ◽  
Yoshitaka Kubojima ◽  
Takashi Nomura ◽  
...  
Keyword(s):  
Moisture Content ◽  
Large Scale ◽  
Water Resistance ◽  
Wood Chips ◽  
Small Scale ◽  
Wood Pellets ◽  
Solid Biofuels ◽  
Rate Of Increase ◽  
Torrefied Biomass ◽  
Indoor And Outdoor

Torrefaction used in combination with pelletization is a promising technology to upgrade solid biofuels and has been demonstrated worldwide. In comparison with normal biomass pellets, which disintegrate under wet conditions, one of the advantages of torrefied biomass pellets is better water resistance. An understanding of the differences in water proof properties for torrefied biomass pellets by different production schemes can promote their further application. In the communication, various torrefied pellets were exposed to indoor and outdoor conditions, and changes in moisture content and diameter were examined. Two production schemes for the torrefied pellets were used for comparison: the torrefaction of wood chips followed by pelletization (pre-torrefaction) and the pelletization of wood chips followed by torrefaction (post-torrefaction). It was found that the post-torrefied pellets had much lower moisture levels than the pre-torrefied pellets in both indoor and outdoor tests. In the outdoor test with no-roof condition, the rate of increase in moisture content for the pre-torrefied pellets was more than double that for the post-torrefied pellets, and the post-torrefied pellets exhibited almost no diameter change. The results on the superior water resistance of post-torrefied pellets were nearly consistent with those reported in previous literature. Torrefied pellets have been considered for industrial use, such as in co-combustion and gasification on a large scale. Taking advantage of the different water resistances, torrefied pellets could also be used by personal and community consumers on a small scale for long-term indoor and outdoor storages as advanced solid biofuels with high waterproof performance, energy density, and lower biodegradation.

Feasibility Tests for a Two-Stage Batch Dryer for Curing Farmer Stock Peanuts1

1999 ◽  
Vol 26 (2) ◽  
pp. 68-73 ◽  
Author(s):  
C. L. Butts ◽  
M. S. Omary
Keyword(s):  
Seed Germination ◽  
Moisture Content ◽  
Removal Rate ◽  
Initial Moisture Content ◽  
Moisture Removal ◽  
Two Stage ◽  
Drying Time ◽  
Milling Quality ◽  
System A ◽  
Support Price

Abstract A two-stage batch dryer for farmer stock peanut was developed by a commercial grain dryer manufacturer and tested at a commercial peanut buying point during the 1996 and 1997 harvests. A 7.3-m diameter grain bin provided the superstructure for two peanut curing chambers. Each chamber had an approximate capacity of 18,000 kg of in-shell peanuts. Comparisons between conventional peanut curing wagons and the bin dryer were conducted. Recorded data included temperature and relative humidity in both type dryers, drying time, moisture content throughout curing, farmers stock grades, milling quality, and seed germination. A total of 451,717 kg were cured in the two-stage dryer and 215,460 kg in conventional dryers. The initial moisture content of peanuts averaged 19% wet basis and dried at an average moisture removal rate of 0.45%/hr. The moisture removal rates for the two dryers were not significantly different. The final moisture content averaged 11%. Moisture content at the time of grading averaged 9%. Farmers stock grades and milling quality were not significantly different. The average quota support price, including LSK for peanuts cured in conventional dryers, was $630.47/1000 kg compared to $636.08/1000-kg peanuts cured in the two-stage dryer. Seed germination averaged 75.8 and 76.1% for conventional and bin-dried peanuts, respectively. The twostage batch dryer was comparable to the current wagon-drying system. A single batch in the two-stage dryer was equivalent to three peanut wagons.

Distribution of Thermophilic and Thermotolerant Fungi in a Spruce-Pine Chip Pile

1972 ◽  
Vol 2 (1) ◽  
pp. 16-26 ◽  
Author(s):  
Roger S. Smith ◽  
A. Ofosu-Asiedu
Keyword(s):  
Weight Loss ◽  
Moisture Content ◽  
Malic Acid ◽  
Associated Factors ◽  
Wood Chip ◽  
Wood Chips ◽  
Thermophilic Fungi ◽  
Thermotolerant Fungi ◽  
Fungal Distribution ◽  
Pinus Spp

A study into the distribution of thermophilic and thermotolerant fungi in a spruce-pine (Picea spp.—Pinus spp.) wood chip pile at Prince George, B.C., was carried out. Five treatments were examined: pine, spruce, spruce containing a core bag of fines, spruce containing a core bag of sterilized spruce chips and spruce containing a core bag of spruce chips inoculated with a Ptychogaster sp. [probably Chrysosporiumpruinosum (Gilman and Abbott) Carmichael]. Samples of wood chips buried at different locations in the chip pile were examined after 3, 6, and 12 month storage periods. From 100 randomly selected chips from each sample, the fungi were isolated on 2% malt, 2% agar, and 0.5% malic acid medium. Data on temperature during storage, pH of wood chips, moisture content, and weight loss at the time of sampling were calculated for the various sampling positions.Thermophilic fungi colonized the inner regions of the wood chip pile where higher wood substance losses occurred, while thermotolerant fungi inhabited the outer regions. Among the thermophilic fungi listed according to frequency of isolation were Byssochlamysemersonii Stolk-Apinis, Allescheriaterrestris Apinis, Sporotrichumthermophile Apinis, Thermoascusaurantiacus Miehe, and Humicolalanuginosa (Griffon and Maublanc) Bunce. The most common thermotolerant fungi were Aspergillusfumigatus Fresenius and C. pruinosum.Fungal distribution was generally related to position in the wood chip pile. Of the associated factors, temperature (17–60 °C) was most strongly related to fungal distribution, whereas treatment, pH of wood chips, and moisture content did not relate to fungal distribution.

An Indirect Passive Solar Dryer for Drying

2011 ◽  
Vol 367 ◽  
pp. 517-524
Author(s):  
A. F. Alonge ◽  
O. O. Oniya
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
Solar Drying ◽  
Drying Time ◽  
Sun Drying ◽  
Two Samples ◽  
Drying System ◽  
Average Size ◽  
Local Materials ◽  
Drying Chamber

A solar drying system designed on the principles of convective heat flow, constructed from local materials was employed in drying yam (Dioscorea Alata). A glass collector having an efficiency of about 0.63 was used along with an absorber for absorbing the heat energy. The drying chamber consisted of drying trays. A chimney fitted at the top centre of the drying chamber enhanced airflow. Air passing through the collector heated up and dried the foodstuff in the drying chamber. The latitude of Ilorin is 8.26oN and the collector angle could be varied . 56o C, 41o C and 71o C were obtained as the maximum attainable temperatures for the drying chamber, ambient and collector respectively. Two samples of yam chips, each weighing 1560g and having an average size of 1cm thick, were dried both inside the dryer and outside the dryer within its surrounding. The initial moisture content of the yam was 70.3% (wet basis) and its final moisture content was 9% (wet basis).The result was compared to natural sun drying. It was observed that the drying time was reduced from 52 hours for sun drying to 45 hours for solar drying. The total cost of the construction was 6, 105 Naira.

Sign in / Sign up

Export Citation Format

Share Document