scholarly journals Combustion characteristics of palm pressed fibres biochar and sub-bituminous Malaysian coal

2018 ◽  
Vol 14 (3) ◽  
pp. 334-337
Author(s):  
Aminu Safana Aliyu ◽  
Nurhayati Abdullah ◽  
Fauziah Sulaiman ◽  
Sadik Umar

In this research, the combustion properties of coal and biochar were investigated and compared to identify the potentiality of biochar for coal replacement application. Biochar is derived from the pyrolysis of palm pressed fibre (PPF) at 400 oC. Thermogravimetric analysis (TGA) was used to study the combustion profiles of the materials. The biochar and coal were combusted via thermogravimetric analysis from ambient temperature to 800 oC at 10 oCmin-1 of heating rate. From the results, biochar showed the high calorific value of 27.30 MJkg-1compared to that of coal 26.21 MJkg-1. Furthermore, biochar comprised the greater content of carbon and fixed carbon. Although, during combustion, coal releases high heat of 0.052 W than biochar which gave 0.049 W. This reveals that the biochar produced from PPF can be a perfect competitor against coal for heat generation. This finding could assist in promoting the application of biomass as an alternative to fossil fuel. 

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Zaenal Arifin ◽  
Amrul Amrul ◽  
Muhammad Irsyad

Coal is still widely used as the main fuel in the industry, especially the power generation industry (PLTU), cement plants and etc. Coal is a fossil fuel whose availability is thinning and its fires produce CO2 emissions that cause a rise in greenhouse gas (GHG) concentricity. On the other biomass is an alternative energy source that is abundant, including empty bunches of oil palm (TKKS), but has poor combustion properties compared to coal when burned directly. The properties of biomass burning can be improved by certain treatment, one of which is through the process of torrefaction. Biomass torrefaction has a calorific value equivalent to sub-bituminous coal B, so it has the potential to be used as an alternative fuel for coal. The purpose of this study was to determine the maximum temperature that occurs in the burner. In this study co-combustion was conducted on simulation of ANSYS program with powder system (pulverized combustion) because this type in recent decades is widely used in industry. In this study conducted a simulation on ANSYS to determine the temperature on the burner and the concentration of emissions produced. The results showed that the simulation of co-combustion burner burner showed the maximum temperature reached 970°C.  The effect of burner and burner temperature in the form of swirl provides sufficient oxygen with more perfect combustion resulting in decreased concentration of CO2 emissions and low concentration of N2 due to higher nozzle temperature. High temperatures lower the concentration of SO2 in the burn chamber.Keyword: Co-combustion, pulverized co-combustion simulation, TKKS torrefaction, burner.


FLORESTA ◽  
2019 ◽  
Vol 49 (4) ◽  
pp. 691
Author(s):  
Raquel Marchesan ◽  
Daniela Mendonça ◽  
Ana Carolina Caixeta Dias ◽  
Renata Carvalho da Silva ◽  
José Fernando Pereira ◽  
...  

The objective of this work was to determine the quality of the Eucalyptus urophilla x Eucalyptus grandis clone charcoal, defining the basic density and wood retractability, apparent density, breaking index, charcoal yield, condensable and non-condensable gas yield, AQI and calorific values, comparing the results of different trunk positions and in two different heating ramps, ramp 1 (R1) with a heating rate of 1.25 ºC/min, final temperature of 450ºC and total of 6 hours, and ramp 2 (R2) with a heating rate of 1.19 ºC/min, final temperature of 500ºC and total time of 7 hours. The six evaluated trees were from a six-year-old cloned tree plantation located in the municipality of Gurupi, in the south of Tocantins state. The specimens for the characterizations were made from wooden discs removed from three trunk positions (base, DBH, top). The Eucalyptus urograndis wood presented basic density considered average (0.47 g/cm³) and good dimensional stability. The charcoal presented an expected yield and high calorific value influenced by the final temperature of the heating ramps, high fixed carbon content, acceptable ash content, as well as a low breaking rate. The results were satisfactory and identified the species as a good energy source.


2012 ◽  
Vol 496 ◽  
pp. 88-93
Author(s):  
Jian Pan ◽  
Lin Wang

The pyrolysis of three stalk was studied to estimate the effect of pyrolysis conditions on product yield, calorific value and proximate analysis. Heating rate and pyrolysis temperature were the main experimental parameters. According to the test, when the heating rates were at 5, 10 and 15°C/min, the low heating rate reacted more thoroughly, got high yield and kept more energy. As the pyrolysis temperature rising; namely 200,300,400 and 500°C;the fixed carbon and gross calorific value were increasing to be 68% and 24.72 MJ/Kg respectively, but the yield was decreasing.


2014 ◽  
Vol 893 ◽  
pp. 807-810
Author(s):  
Zaliman Sauli ◽  
Rajendaran Vairavan ◽  
Vithyacharan Retnasamy

High power light emitting diodes are currently challenged by thermal issue of high heat generation which limits the reliability and efficiency. Each component in the LED package has a significant role in heat dissipation. In this paper, a simulation study was done to scrutinize the influence of heat slug shape on the heat dissipation of single chip LED package using Ansys version 11. Two types of heat slug shapes, rectangular and cylindrical were used. The analysis was carried out under natural convection condition at ambient temperature of 25°C. Simulated results indicate that rectangular shape heat slug exhibits better heat dissipation.


2016 ◽  
Vol 78 (9-2) ◽  
Author(s):  
Hasan Mohd Faizal ◽  
M. Amin M. Jusoh ◽  
Mohd Rosdzimin Abdul Rahman ◽  
S. Syahrullail ◽  
Z. A. Latiff

The climate change has driven towards transformation from the high energy dependence on fossil fuel to inexhaustible renewable energy such as solar, wind, mini hydro and biomass. In Malaysia, abundant of palm biomass residues are produced during the processing of fresh fruit bunch. Therefore it is inevitable to harness these bioenergy sources in order to prevent waste accumulation at adjacent to palm mills. In order to utilize such bioenergy sources and to cope with the fast growing demand of energy, combination technique of densification and torrefaction is one of the potential ways to be practised. In the present study, the physical and combustion properties of torrefied empty  fruit bunch (EFB) briquettes were investigated experimentally with constant nitrogen flow rate of 1 l/min , for various torrefaction temperatures (225-300). Before torrefaction process, EFB briquettes were initially produced under controlled condition with compaction pressure of 7 MPa and briquetting temperature of 150. In general, the torrefied EFB briquettes were successfully produced in the present study. The results show that an increase in torrefaction temperature from 225  to 300  causes a significant increase in gross calorific value (from around 17400 kJ/kg to 25000 kJ/kg), fixed carbon content (from 16.2% to 46.2%) and ash content (from 2.4% to 17.2%). On the other hand, relaxed density and volatile matter decrease, from 1017 kg/m3 to 590 kg/m3 and from 73.1% to 29.7%, respectively. As a conclusion, the gross calorific value and fixed carbon content are improved due to torrefaction. In addition, it was found that gross calorific value and moisture content of the torrefied EFB briquettes fulfil the requirement for commercial briquette production as stated by DIN51731 (gross calorific value>17500 kJ/kg and moisture content <10%). 


Author(s):  
O. A. Sotannde ◽  
A. M. Dadile ◽  
M. Umar ◽  
S. M. Idoghor ◽  
B. D. Zira

Aims: The study explored the combustion properties of woods and barks of some selected trees and the mixtures of the two in order to map out how fuel material composition affect the combustion properties of biomass materials. Study Design: The study is a two-factor factorial experiment in a completely randomized design. The main factors are the tree species and fuel material types. Place and Duration of Study: Tree samples used for this study were coppiced stems harvested from smallhold farm plots along the Damaturu - Gujba fuelwood corridors in Yobe State. The analytical study was carried out in Wood and Fibre Science Laboratory of the Department of Forestry and Wildlife, University of Maiduguri, Nigeria between April 2018 and December 2019. Methodology: Ten tree species were used for this study. Each species was replicated 3-times, making a total of 30 stems with their dbh between 10 and 15 cm. A sample billet of 20 cm log was cut from each stem at 10 cm below and above dbh. Each billet was debarked, chipped separately and dried to approximately 12% moisture content. From the chips, 100% wood, 95%W-5%B, 90%W-10%B and 100% bark fuel material samples were created, grinded with mechanical grinder and sieved to approximately 0.4 mm particle size based on ASTM D2013-86. The sieved samples obtained were then analyzed for their percentage moisture content, volatile matter, fixed carbon, ash and gross calorific values using ASTM standard methods. The data obtained were subjected to Analysis of variance from which % variance component and LSD were computed α = 0.05 and 0.01 level of significance. Results: All the measured parameters varied significantly among the tree species and the compositions of the fuel materials obtained from them. Majority of the variation in the fuelwood properties were attributed to the composition of the fuel materials obtained from the trees rather than the species they were made of. On the average, moisture content of the samples ranged from 27.66 to 40.44%, volatile matter (61.38 to 75.11%), ash (0.52 to 2.42%), fixed carbon (24.19 to 36.20%) and gross calorific value (32.99 to 33.02 MJ.kg-1). The moisture and ash contents of the fuel materials obtained from all the tree species increased with the level of bark inclusion whereas, volatile matter content and gross calorific values decreased significantly with level of bark inclusion (P < 0.05). Also, gross calorific value of the fuel materials correlates positively with volatile matter and fixed carbon contents. But, correlate negatively with moisture and ash contents. Among the studied tree species, chips obtained from A. leiocarpus had the highest energy value, followed by C. arereh and B. aegyptiaca while P. reticulatum, A. sieberiana and C. lamprocarpum had the least energy value in that order. Conclusion: Based on their energy value and ash content, minimizing the bark content in wood chips is important from energy and environment point of view. Therefore, chips with 100% wood and those with 5% bark inclusions are recommended for heat generation.


2019 ◽  
Vol 5 (12) ◽  
pp. 37-46
Author(s):  
K. Chalov ◽  
Yu. Lugovoy ◽  
Yu. Kosivtsov ◽  
E. Sulman

This paper presents a study of the process of thermal degradation of crosslinked polyethylene. The kinetics of polymer decomposition was studied by thermogravimetry. Crosslinked polyethylene showed high heat resistance to temperatures of 400 °C. The temperature range of 430–500 °C was determined for the loss of the bulk of the sample. According to thermogravimetric data, the decomposition process proceeds in a single stage and includes a large number of fracture, cyclization, dehydrogenation, and other reactions. The process of pyrolysis of a crosslinked polymer in a stationary-bed metal reactor was investigated. The influence of the process temperature on the yield of solid, liquid, and gaseous pyrolysis products was investigated. The optimum process temperature was 500 °C. At this temperature, the yield of liquid and gaseous products was 85.0 and 12.5% (mass.), Respectively. Samples of crosslinked polyester decomposed almost completely. The amount of carbon–containing residue was 3.5% by weight of the feedstock. With increasing temperature, the yield of liquid products decreased slightly and the yield of gaseous products increased, but their total yield did not increase. For gaseous products, a qualitative and quantitative composition was determined. The main components of the pyrolysis gas were hydrocarbons C1–C4. The calorific value of pyrolysis gas obtained at a temperature of 500 °C was 17 MJ/m3. Thus, the pyrolysis process can be used to process crosslinked polyethylene wastes to produce liquid hydrocarbons and combustible gases.


Proceedings ◽  
2021 ◽  
Vol 52 (1) ◽  
pp. 4
Author(s):  
Roberta Mota-Panizio ◽  
Luis F. Carmo-Calado ◽  
Octávio Alves ◽  
Catarina Nobre ◽  
J. L. Silveira ◽  
...  

The behavior of chars from the carbonization process were studied when the lignocellulosic biomass was incorporated into the waste of electrical and electronic equipment for chlorine removal. Tests were performed at 300°C with a heating rate of 15°C/min and residence time of 60 min. Compositions studied had 100, 75, 50, 25 and 0% of waste electrical and electronic equipment (WEEE) in the mixtures. The composition of 50% WEEE with 50% lignocellulosic biomass presented the best char properties, having an increment of the calorific value in 5.5% relative to the initial value, and chlorine removal of 23.4% when compared to the forestry biomass.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1192
Author(s):  
Aneta Szymajda ◽  
Grażyna Łaska ◽  
Magdalena Joka

Recently, biomass application as a renewable energy source is increasing worldwide. However, its availability differs in dependence on the location and climate, therefore, agricultural residues as cow dung (CD) are being considered to supply heat and/or power installation. This paper aims at a wide evaluation of CD fuel properties and its prospect to apply in the form of pellets to direct combustion installations. Therefore, the proximate, ultimate composition and calorific value were analyzed, then pelletization and combustion tests were performed, and the ash characteristics were tested. It was found that CD is a promising source of bioenergy in terms of LHV (16.34 MJ·kg−1), carbon (44.24%), and fixed carbon (18.33%) content. During pelletization, CD showed high compaction properties and at a moisture content of 18%,and the received pellets’ bulk density reached ca. 470 kg·m−3 with kinetic durability of 98.7%. While combustion, in a fixed grate 25 kW boiler, high emissions of CO, SO2, NO, and HCl were observed. The future energy sector might be based on biomass and this work shows a novel approach of CD pellets as a potential source of renewable energy available wherever cattle production is located.


Sign in / Sign up

Export Citation Format

Share Document