Impact Resistance Index Research Articles

Co-pyrolysis of plastic waste and eucalyptus waste wood for fuel pellets production: A study of fuel, mechanical, and combustion characteristics under varying binder proportion

The study explores the effect of varying molasses proportions as a binder on the characteristics of densified char obtained through the slow co-pyrolysis of plastic waste and Eucalyptus wood waste (Waste low-density polyethylene – Eucalyptus wood (WLDPE–EW) and Waste Polystyrene – Eucalyptus wood (WPS–EW)). Pyrolysis was conducted at 500 °C with a residence time of 120 min, employing plastic to wood waste ratios of 1:2 and 1:3 (w/w). The focus was on how varying the proportion of molasses (10–30 %), influences the physical and combustion properties of the resulting biofuel pellets. Our findings reveal that the calorific value of the pellets decreased from 28.94 to 27.44 MJ/Kg as the molasses content increased. However, this decrease in calorific value was compensated by an increase in pellet mass density, which led to a higher energy density overall. This phenomenon was attributed to the formation of solid bridges between particles, facilitated by molasses, effectively decreasing particle spacing. The structural integrity of the pellets, as measured by the impact resistance index, improved significantly (43–47 %) with the addition of molasses. However, a significant change in the combustion characteristics depicted by lower ignition and burnout temperatures were observed due to decrease in fixed carbon value and increase in volatile matter content, as the proportion of molasses increased. Despite these changes, the pellets demonstrated a stable combustion profile, suggesting that molasses are an effective binder for producing biofuel pellets through the densification of char derived from the co-pyrolysis of plastic and Eucalyptus wood waste. The optimized molasses concentration analyzed through multifactor regression analysis was 16.96 % with 28 % WLDPE proportion to produce WLDPE–EW char pellets. This study highlights the potential of using molasses as a sustainable binder to enhance the mechanical and combustion properties of biofuel pellets, offering a viable pathway for the valorization of waste materials.

Application of principal component analysis (PCA) to the study of the influence of the thermochemical treatment process of tropical wood sawdust on the calorific, mechanical, physicochemical and combustion properties of the resulting fuel briquettes

Despite its potential for environmentally friendly energy production, lignocellulosic biomass has less advantageous physicochemical properties that limit its optimal industrial use. This study used principal component analysis (PCA) to evaluate the effects of two thermochemical processing methods (torrefaction and carbonization) on the calorific, physicochemical, mechanical and combustion properties of the resulting biofuels. Various types of tropical sawdust (Dabema, Dibetou, Fraké, Samba and Iroko) are subjected to these treatments, then densified and characterized for energy applications. Specific fuel consumption varies from Samba torrefied (Sam t: 0.69 kg/L) to Samba carbonized (Sam c: 1.48 kg/L). Higher heating values range from Samba torrefied (Sam t: 23983 kJ/kg) to Iroko torrefied (Iro t: 27,442 kJ/kg). Burning speed varies from Samba carbonized (Sam c: 3.07 g/min) to Iroko torrefied (Iro t: 4 g/min). The impact resistance index ranges from 187.5 to 500% for Dibetou torrefied (Dib t) and Samba carbonized (Sam c), respectively. Densities are between Samba carbonized (Sam c: 297.83 kg/m3) and Dibetou carbonized (Dib c: 393.69 kg/m3). The results indicate that these techniques are promising approaches for improving biomass properties. In sum, the PCA reveals that the effect of treatment type on fuel characteristics also depends on the properties of the initial biomass.

Physicochemical characterization of briquette fuel produced from cocoa pod husk case of Cameroon

This paper aims to prepare and evaluate the physicochemical and energetic properties of briquette fuel made from cocoa pod husk. For briquette preparation, cocoa pod husk was dried, carbonised, crushed, mixed using binder, compacted, and finally the briquettes obtained were dried. The briquettes produced were characterised by proximate analysis, ultimate analysis, infrared spectroscopy, and thermogravimetric analysis using the American Society for Testing and Materials (ASTM) and the European Committee for Standardisation (CEN) standards. The results from the proximal analysis obtained (10.5%), (6.5%), (34.7%), and (58.8%), respectively, for moisture content, ash content, volatile matter, and fixed carbon, are satisfactory values. The results from the ultimate analysis found are 53.2%, 5.2%, and 34.4%, respectively, for carbon, hydrogen, and oxygen content, while H/C and O/C gave 1.17 and 0.48, respectively. The Higher Heating Value (17.941 MJ/kg) proved high thermal stability, with the highest mass loss of 32.50% at 361°C due to the high extractive content and the aromatic structure of the polymer. The presence of C-O, CC, CHx, and OH groups was noticed, while the fuel value index (FVI) and impact resistance index (IRI) showed 1104% and 125%, respectively. These results indicated that the abundance of these residues in landfills could serve as an alternative fuel energy source with environmental friendly features and contribute to the economic growth of the country.

Fabrication of briquettes from charcoal fines using tannin formaldehyde resin as a binder

Charcoal fines, a waste emanating from charcoal transportation and handling, were utilized in the fabrication of briquettes using tannin-formaldehyde resin as a binder to meet ever expanding energy demand. A collection of four briquette samples were fabricated with binder proportions of 25%, 30%, 35%, and 40%. These briquettes were characterized using Fourier transform infra-red and thermogravimetric analyses techniques. Furthermore, the briquettes were subjected to physical parameters namely bulk density, impact resistance index (IRI), water resistance index (WRI), and water boiling test. The bulk density of the briquettes was 1.153-1.495 g/cm<sup>3</sup>, IRI was 6.79-73.33, and WRI was 99.24-99.29. The briquettes exhibited an ignition time of 5.38-6.21 minutes, boiling time of 19.50-37.20 minutes, burning rate of 3.20-8.70 g/minute, and a specific fuel consumption of 54.70-64.30 g/L. Higher heating value range for the briquettes was 19.76-23.23 MJ/kg and the briquettes with 40% binder showed the best physical qualities with great fuel potential. Therefore, the fabricated briquettes have demonstrated great potential as a source of cleaner and sustainable energy.

Characterization of hybrid charcoal briquettes from date palm and pistachio residues and bio-based binders

As a solid biofuel, briquette is a renewable energy technology that has attracted enormous attention in the sustainable energy sector and can replace fossil fuels to reduce greenhouse gas emissions. This research developed hybrid charcoal briquettes using biochar of date palm and pistachio residues. Starch, molasses, and bitumen were used as binders to produce the hybrid briquettes with different contents. The briquettes were compacted at pressure levels of 100 bar using a hydraulic press. Compressed density, relaxed density, compaction ratio, impact resistance index (IRI), shatter index, and compressive strength were determined using standard procedures. The results showed that the relaxed density of the hybrid briquettes ranged from 0.63 to 1.03 g/cm3, and their compressive strength ranged from 0.46 to 22.17 N/mm. The briquettes made of the starch binder at a content of 20% exhibited superior properties. The higher the binder content, the better the quality of the briquettes for storage and transportation.

Efficiency of place-based innovated briquettes making technologies for sustainable cooking energy in Tanzania

Globally, more than 2.8 billion people don’t have access to electricity. Whereas about 550 million of them live in Africa. Hence, they opt to go for cheaply available sources like charcoal and firewood for their cooking and heating purposes in their daily domestic and industrial applications. More than 80% of sub-Saharan Africans and 90% of East Africans rely on biomass energy for their domestic and industrial heating purposes. In Tanzania, more than 85% of the population depends on wood-based energy for cooking. This dependency is directly linked to climate change as it promotes deforestation and has the potential to lead to desertification. Currently, a focus is on the use of renewable energies, especially recycled bio-waste (bio-briquettes) as an alternative to charcoal and firewood. Both government and private institutions have initiated and taken the lead in making sure that the effort is of high value; however, the available briquette-making machines are expensive, complex to use, and demand electricity which adds more costs to production, hence making the briquette production a non-economic business adventure within Tanzania. In addressing the problems, this study aimed at conducting an inventory study in order to come up with place-based briquette technologies suiting youth and female unemployed groups. A human-centered design concept was used in inventing two briquetting machines. One uses screw pressing mode (Peyam Screw Press), while the other one uses a hydraulic jerk system (the Briquetter). The machines were tested for; Type Test (compression method), user friendliness (gender sensitiveness approach), and acceptability (market validation method). Results revealed that the machines produce briquettes of high quality that passed both the Impact Resistance Index (IRI) and Water Absorption Resistance (WAR) tests at a threshold of >50%. Moreover, they offer reliable production and have passed social acceptability tests, hence they should be considered for adaptation.

Characteristics of briquettes from plastic pyrolysis by-products

Pyrolysis has been proven as a method to reduce plastic waste and produce useful products, especially liquid fuels. However, plastic pyrolysis also produces gases and char as by-products which are being investigated for useful products. Therefore, our present study aims to investigate the char characteristics of plastic pyrolysis for further use as briquettes. Seven samples of char by-products from the pyrolysis process of low-density polyethylene (LDPE) plastic at various reaction temperatures and catalyst types were studied. The proximate test is used to determine the properties of char such as moisture content, ash, volatile matter, and fixed carbon while the bomb calorimeter is used to determine the calorific value. Briquettes are formed by mixing 4 grams of char and 0.5-1 gram of binder (1% starch and 90% water). The briquettes were formed into solid cylinders with a diameter of 1.75 cm and formed with a pressure of 10 kg/cm2. Furthermore, the impact resistance index (IRI) was used to test the performance of the briquettes and showed an IRI value between 100 and 200. However, of the seven char samples tested, three of them were impossible to process into briquettes because they melted during the combustion test.

The Anti-Impact Characteristics of Cables under Impact Load

The cable plays a vital role in roadway support. As the last barrier to prevent roof collapse and impact disaster accidents, it is of great significance to study stress characteristics of cables under impact dynamic load to guide the rock burst roadway support. With high-strength cables of Φ21.6 and Φ21.8 mm and low-resistance high-extension cables of Φ21.5 mm as examples, this paper studied the instantaneous mechanical state and energy dissipation characteristics of different types of cables under impact loads by using impact testing machines and high-frequency data acquisition system. The results show that the impact process can strengthen the strength of the cable. The strength and elongation of anchor cables are a pair of characteristic indexes with an inverse relationship. Simply increasing one index cannot improve the overall impact resistance of the cable. To quantitatively characterize the impact resistance and energy absorption effect of cables, the impact resistance index k was introduced. The smaller the index, the better the energy absorption effect of cables. In the process of dynamic load impact of high-strength cable, about 43.7% of the total energy is dissipated disordered in the form of mechanical energy. The dynamic load impact process of low-resistance and high-extension cables is similar to the viscoelastic impact. In the collision compaction stage, the force of the cable is basically constant. Most of the impact energy is absorbed or transformed by the cable, about 17.7% of which is mostly dissipated in the form of mechanical energy. The disordered dissipated mechanical energy is less, so the impact resistance and energy absorption effect of this cable are better. The cable plays an important role in the process of bearing the dynamic load of surrounding rock. The anti-impact performance index of cables should be considered in dynamic load impact roadway support design.

Behavior of Ultra-High-Performance Concrete with Hybrid Synthetic Fiber Waste Exposed to Elevated Temperatures

The reinforcement of ultra-high-performance concrete (UHPC) with fibers was investigated in this study. Concrete is the most widely used manmade construction material, and UHPC has remarkable mechanical properties. The mechanical properties of UHPC can be modified by a variety of curing procedures and the amount of cement used. This study aimed to examine the impact of fiber reinforcement, temperature, and exposure time on UHPC. Initially, the temperature for UHPC was changed from 300 °C to 500 °C and the exposure time set to 1 and 2 h. Various combinations of the ultrasonic pulse, thermal conductivity, compressive strength, flexural strength, splitting, modulus of elasticity, and drop hammer impact (impact resistance, impact energy, and ductility index) were investigated after 91 days of steam curing. For steam curing, the temperature was kept at 90 °C for three days. The mechanical characteristics of UHPC were the primary focus of this research. The test results showed that the accelerated curing regime achieved a maximum compressive strength of 102.6 MPa for UHPC specimens without fibers and 124.7 MPa for UHPC specimens with fibers, which represents a 22% increase in compressive strength. When compared to UHPC without fibers, all the qualities of UHPC with fibers were improved, especially when subjected to high temperatures. The incorporation of hybrid synthetic waste fibers was a key aspect in developing new ultra-high-strength concrete features.

Heterogeneous microstructure in nonequiatomic MoNbTaVW refractory high entropy alloy after high pressure torsion: Evolution mechanisms and mechanical properties

The non-equiatomic MoNbTaVW refractory high entropy alloy (HEA) has been systematically investigated with the intent of developing a heterogeneous microstructure using high pressure torsion (HPT). The heterogeneous microstructure is successfully developed and is characterized by coarse grains, kink bands and ultrafine grains (UFGs) at strain levels (ε) ≈ 0–2.4, 2.4–6.2, and 8.7-higher, respectively. In the initial stage (ε ≈ 2.4–6.2) of deformation, the microbands (slip bands and kink bands) developed within the grain depending on the orientation. The slip bands are developed by slip activity along {110} <11‾1 > slip system, and kink bands are formed due to slip-induced lattice rotation about the <110> axis with activation of {112}<111‾ > slip system. At higher strain (ε > 8.7), high density of accumulated low angle grain boundaries (LAGBs) dynamically recovered into polygonized subgrain structures that later transform into high angle grain boundaries (HAGBs) due to gradual lattice rotation. The synchrotron diffraction pattern confirms that the single-phase bcc structure is stable during the deformation, and no phase transformation takes place. Further, the microhardness values for coarse grained, kink banded and UFG microstructure are determined to be 8.1, 10.3, and 12.5 GPa, respectively. The mechanical behaviour of the HPT microstructure indicates that the UFG have a good impact resistance and elastic recovery index, while the coarse grains has inherent plasticity and better fracture resistance. The kink band microstructure remarkably combines strong impact loading and inherent plasticity. Therefore, the hierarchical distribution of these microstructures can achieve a superior combination of strength and ductility

Comparison of industrial wastes as a binder in the agglomeration of coal fines

There is limited work reported in the literature on the use of waste material as a coal binder, and no study has reported the use of industrial petroleum waste as a binder for fine discard bituminous coal. In this study, the binding properties of five industrial wastes were evaluated to determine their efficacy in the agglomeration of Highveld inertinite-rich coal fines; four waste products from the petrochemical industry and one waste recycled low-density polyethylene (LDPE) were used as binders. Therefore, the addition of waste binders was investigated to use the briquettes as carriers to reduce waste. The compressive strength, CS (MPa), impact resistance index, IRI (−), friability index, FR (%), abrasion resistance, AR (%), and water resistance index, WRI (%) of the briquettes were determined to evaluate the mechanical strength of the briquettes. The binderless briquettes had a maximum CS of 3.4 MPa, higher than the minimum CS of bituminous coal (2.1 MPa). The optimal concentration for each binder, based on mechanical strength (CS, IRI, FR), was determined as 15% Binder A (4.1 MPa; 68; 80%), 20% Binder B (2.3 MPa, 87, 71%), 20% Binder C (8.2 MPa, 1000, 100%), 5% Binder D (2.4 MPa, 21, 46%) and 5% Binder E (5.3 MPa, 97, 52%). Briquettes bound with 20% Binder B and 5–10% Binder E were water-resistant. The briquettes were matched with suitable industrial processes based on the obtained mechanical strength and physiochemical properties. The binderless and the Binder B and D bound briquettes may be suitable for PCC boilers because their strength is high enough to enable transportation and low enough not to inhibit pulverising. Binders B, C and E bound briquettes may be more suited for use in a fixed-bed-‍gasifier. None of the binders was recommended for use in blast furnaces due to the high ash yield, low volatile matter content and lack of swelling properties.

Briquetting of subbituminous coal and torrefied biomass using bentonite as inorganic binder

The use of inorganic binder for briquetting of subbituminous coal and torrefied biomass for energy generation is scarce. The present study focuses on the physicomechanical durability and energy content of briquettes produced from subbituminous coal (SubC) and torrefied biomass (TM) using bentonite as binder. Briquettes were produced using 95% SubC and 5% TM. Bentonite was varied at 2–10% of the total SubC and TM weight. The briquettes were produced with a constant pressure (28 MPa) in a hydraulic press. The briquettes were primarily cured at room temperature and then at 300 ^circ{rm C} in a tubular furnace under an inert condition for 60 min. The density and water resistance (WRI) of the briquettes were evaluated. Drop to fracture (DF), impact resistance index (IRI), cold crushing strength (CCS) and tumbling strength index (TSI+3 mm) of the briquette were obtained. The reactivity index (RI), proximate, ultimate and calorific values analyses were assessed based on different ASTM standards. Microstructural studies and elemental mapping were carried out using scanning electron microscope equipped with EDS and electron probe microanalyzer. The density increased with increment in bentonite content. The WRI decreased with increase in bentonite while the least (95.21%) was obtained at 10% binder content. The DF and IRI ranges from 100 to 150 and 2000–3000, respectively. The CCS were in the range of 19.71 to 40.23 MPa. The RI varies from 34 to 50%. Fixed carbon, carbon and calorific values were impaired as the bentonite content in the briquette increases. Oxygen and silica bridges with mechanical interlocking were observed on the micrographs of the briquettes. The briquettes produced with 2% bentonite content have better physicomechanical durability with equivalent energy content. It is recommended as feedstock for thermal and metallurgical applications.

Physicochemical Characteristics of Biofuel Briquettes Made from Pecan (Carya illinoensis) Pericarp Wastes of Different Particle Sizes.

Pecan nut (Carya illinoensis) pericarp is usually considered as a waste, with no or low value applications. Its potential as a densified solid biofuel has been evaluated, searching for alternatives to generating quality renewable energy and reducing polluting emissions in the atmosphere, based on particle size, that is an important feedstock property. Therefore, agro-industrial residues from the pecan nut harvest were collected, milled and sieved to four different granulometry: 1.6 mm (N° 12), 0.84 mm (N° 20), 0.42 mm (N° 40), and 0.25 mm (N° 60), used as raw material for biofuel briquette production. The carbon and oxygen functional groups in the base material were investigated by Fourier transform infrared spectroscopy (FTIR) and proximate analyses were performed following international standards, for determining the moisture content, volatile materials, fixed carbon, ash content, and calorific value. For the biofuel briquettes made from base material of different particle sizes, the physical characteristics (density, hardness, swelling, and impact resistance index) and energy potential (calorific value) were determined to define their quality as a biofuel. The physical transformation of the pecan pericarp wastes into briquettes improved its quality as a solid biofuel, with calorific values from around 17.00 MJ/kg for the base material to around 18.00 MJ/kg for briquettes, regardless of particle size. Briquettes from sieve number 40 had the highest density (1.25 g/cm3). Briquettes from sieve number 60 (finest particles) presented the greater hardness (99.85). The greatest susceptibility to swelling (0.31) was registered for briquettes with the largest particle size (sieve number 20). The IRI was 200 for all treatments.

Production of carbonized briquettes from charcoal fines using African Elemi (Canarium Schweinfurthii) resin as an organic binder

ABSTRACT This study investigated the use of African Elemi (Canarium Schweinfurthii) resin as a binder for the production of carbonized briquettes from charcoal fines. The binder and charcoal fines were characterized through proximate analysis, ultimate analysis, higher heating value, and SEM. Four briquette samples (B25, B30, B35, and B40) with a ratio of charcoal fines: binder of 3:1, 7:3, 13:7, and 3:2, respectively, were produced at a compaction pressure of 5.92–7.96 MPa. The physical properties of the briquettes determined were bulk density, impact resistance index (IRI), compressive strength, splitting tensile strength, water resistance index (WRI), and morphology. The chemical properties of the briquettes determined were proximate analysis, ultimate analysis, higher heating value (HHV), and energy density. One-way ANOVA and Fisher’s LSD were used to analyze the chemical properties of briquettes. The briquettes had a bulk density of 0.770–1.036 g/cm3, IRI of 2.90–73.33, compressive strength of 2.25–10.94 N/mm2, splitting tensile strength of 0.09–0.42 N/mm2, WRI of 99.26–99.29, and an HHV of 29.7–31.3 MJ/kg. The briquette properties were found to be comparable to results from other studies.

Biomass valorization for energy applications: A preliminary study on millet husk

This study used millet husk which is a waste and gum Arabic as binder to develop briquettes for domestic cooking in Northern Nigeria. The objective was to investigate the effect of particle sizes, compaction pressures and binder concentrations on the physical, mechanical and thermal characteristics of the briquettes. Furthermore, the study also accessed the economic viability of the usage of millet husk briquettes as fuel. Particle sizes of 0.3, 0.4, 0.6 and 1.7mm; compaction pressures of 10, 15, 20 and 25 MPa and binder concentrations (gum Arabic) of 25, 30, 35 and 40% were used to densify the millet husk mixed with gum Arabic at room temperature with the aid of hydraulic press. The caloric value (15.27 MJ/kg) was determined using ASTM D2015, other physical and chemical properties of the millet husk was determined by proximate and ultimate analysis which showed that volatile matter (76%), ash content (6.5%) and sulphur content (0.3%) are within the recommended range for domestic cooking fuels. It was found that the density (438 kg/m3 and 669 kg/m3), impact resistance index (70–93%) and compressive strength of the millet husk briquettes increased with compaction pressures and binder concentrations and decreases with increase in particle sizes, while for porosity of the briquettes, the above case was a reversal. The performance of the briquettes for domestic cooking were accessed by ignition time (109 and 140 s); burning rate (0.09 g/s and 0.18 g/s) and water boiling test which took 5 and 11 min to boil 1 L of water as compared to fuel wood that takes longer. Economic analysis showed that utilizing the millet husk generated in northern Nigeria will lead to huge savings in fuel wood consumption, monetary savings of about ₦ 9,257,869,268.62, and reduction in deforestation and its attendant problems. A structured questionnaire as used to ascertain the acceptability of the produced briquettes. Most of the respondents (90%) in a survey expressed willingness to use millet husk briquette as replacement for wood. The study concludes that millet husk is good for briquetting for energy applications with high potential to reduce energy poverty, minimal waste and reduce indoor pollution for domestic cooking therefore, making millet cultivation more profitable in Northern Nigeria.

Proximate Analysis and Strength Properties of Carbonized Woods from the Most-Used Tropical Timbers from the Afram Plains, Ghana’s Charcoal Production Hub

ABSTRACT Charcoal is a brittle, black carbon residue produced from the carbonization of cellulosic materials for energy. Its properties vary per the timber carbonized. It is often used regardless the intended purpose and the timber carbonized. However, for objective utilization, the proximate and strength properties of carbonized woods from six widely-used timbers in the Afram Plains, Ghana, were investigated. Moisture content for the carbonized woods met the recommended Standards. Hence, would be hardly alterable under normal atmospheric conditions. Their bulk densities ranged from 497.39 ± 3.13 kgm−3 (Azadirachta indica) to 680.50 ± 8.58 kgm−3 (V. paradoxa). E. ivorense charcoal produced the least volatile matter (VM) (18.66 ± 0.73%), ash (1.94 ± 0.04%), much great Calorific value (28208.45 ± 743.72 kJkg−1), the greatest Fixed Carbon Content (73.13 ± 0.69%), Impact Resistance Index (325 ± 23.07), and compressive strength (29.39 ± 1.82 Nmm−2). It would generate much heat and fracture less and could be suitable for use in the Metallurgical Industry. The great VM from all the carbonized woods (18.66 ± 0.73% to 51.91 ± 0.49%) also makes them best suited for outdoor use (e.g., barbecue-making). As they possess varied properties, their intended uses should be guided by their properties for improved performance.

Physical and mechanical characteristics of composite briquette from coal and pretreated wood fines

Melina wood torrefied at 260 °C for 60 min was agglomerated with lean grade coal fines into composite briquettes using pitch as binder. Torrefied biomass (3%–20%) and coal fines (80%–97%) were blended together to produce the composite briquettes under a hydraulic press (28 MPa). The briquettes were cured at 300 °C. Density, water resistance, drop to fracture, impact resistance, and cold crushing strength were evaluated for the composite briquettes. The proximate, ultimate, and calorific value analyses were carried out according to different ASTM standards. Microstructural studies were carried out using scanning electron microscope and electron probe microanalyzer equipped with energy dispersive x-ray. Fourier Transform Infrared Spectrophotometer (FTIR) was used to obtain the functional groups in the raw materials and briquettes. The density of the composite briquettes ranged from 0.92 to 1.31 g/cm3 after curing. Briquettes with < 10% torrefied biomass has good water resistance index (> 95%). The highest cold crushing strength of 4 MPa was obtained for briquettes produced from 97% coal fines and 3% torrefied biomass. The highest drop to fracture (54 times/2 m) and impact resistance index (1350) were obtained for the sample produced from 97% coal and 3% torrefied biomass. The fixed and elemental carbons of the briquettes showed a mild improvement compared to the raw coal. The peaks from FTIR spectra for the briquettes shows the presence of aromatic C=C bonds and phenolic OH group. The composite briquettes with up to 20% torrefied biomass can all be useful as fuel for various applications.

Effect of Sawdust Particle Size on Physical, Mechanical, and Energetic Properties of Pinus durangensis Briquettes

Particle size is a physical property that sometimes limits the quality of briquettes, so it is recommended to use different sizes in mixtures for their manufacture. The objective of this research was to evaluate the effect of different particle sizes of sawdust in mixtures on some physical, mechanical, and energetic properties of briquettes made from Pinus durangensis sawdust, as well as set the ranges within the appropriate values found to obtain desired values. Three particle sizes were established (large, medium, and small), and 10 mixtures were prepared using different percentages of each particle classification. The particle density, volumetric swelling, compressive strength, impact resistance index (IRI), and gross calorific value of the briquettes were evaluated. For the determination of optimal mixtures, the surface response methodology was used under a three-factor simplex-lattice model. The particle density values were in the range 0.92 to 1.02 g cm−3 and the volumetric swelling was 0.96 to 3.9%. The highest resistance to compression was 37.01 N mm−1, and the IRI was found in the range of 53 to 107%. The gross calorific values were from 19.35 to 21.63 MJ kg−1. The selection of different particle sizes for the mixtures increases the quality of the briquettes.

Green refuse derived fuel preparation and combustion performance from the solid residues to build the zero-waste city

The re-utilization or recycling of waste completely was a big task to build the zero-waste city, and refuse derived fuel (RDF) preparation might be a potential way to recycle those variations organic wastes from industry and municipal sector, while the chemical binder was usually employed to match the mechanical property of RDF. In this work, a green-RDF was developed using wastes with different sources directly. Resin-like industrial solid waste, i.e., automotive stamping gaskets and electronic packing wastes (AE = 56%), anaerobic digestion sludge (ADS = 24%) and industrial desiccant residue (IDR = 20%), were selected and optimized to prepare green-RDF based on the previous market survey and characteristics analysis. The extending rate (ER), impact resistance index (IRI), and lower heating value (LHV) was 17.51%, 116.67% and 6.84 MJ/kg. The combustion performance of RDF was operated through TG/DSC-MS and combustion simulator with on-line FTIR gas analyzer simultaneously. The releasing temperature range for SO2 and NOx was narrowed to 211–401 °C and 212–803 °C, with the SO2 and NOx reduction of 63% and 26%, respectively, since IDR additives contributed to fixation of them in the residues through the chemical adsorption and oxidation reduction reaction. Green-RDF might be a promising method for the energy recovery from solid waste with different sources.

Valorization of briquettes fuel using Pinus spp. sawdust from five regions of Mexico

This research characterized briquettes made with Pinus spp. sawdust without the use of additives. For this purpose, 19 samples of sawdust from different wood industries located in five states of the Mexican Republic were used. The densification process was carried out in a vertical hydraulic piston laboratory briquette machine. The briquettes were made with 40 g of sawdust, at 50 °C, 20 kPa and pressing for 5 min. The results obtained varied as follows: moisture content (4.1% to 7.2%), density (813.9 to 1,014.4 kg/m3), volumetric expansion (7.4% to 37.3%), compressive strength (4.9 to 40.8 N/mm), impact resistance index (46.7% to 200%), ash (0.1% to 1.1%), volatile matter (82.9% to 90.7%), fixed carbon (8.9% to 16.4%), and calorific value (20.5 to 22.8 MJ/kg). The density of the briquettes was within the “acceptable” classification (800 to 1,200 kg/m3). It was observed that, the higher the density, the lower the volumetric expansion, the higher the compressive strength, and the higher the impact resistance index. According to the ash content, the briquettes could achieve international quality. Due to high volatile matter values, rapid combustion of the briquettes with little generation of toxic smoke would be expected. Fixed carbon and calorific value results were acceptable.