Density Of Briquettes Research Articles

Briquetting of waste glass cullet fine particles for energy saving glass manufacture

Fine particles of glass cullet (fines) arising during glass recycling cannot presently be recycled into glass manufacture due to the potential for bubble formation and foaming. Consolidation of glass fines into briquettes could enable their re-introduction into furnaces, reducing waste and glass melting energies. Properties of briquetted cullet fines and briquette melting behaviour in soda-lime-silica glass batches are presented. Morphology and density of glass fines and briquettes; and briquette mass and mechanical properties as functions of time after formation were analyzed. Compressive strength increases linearly with time after briquette formation. With slight batch modifications to maintain the same final glass composition, up to 15 wt % briquettes were successfully added to a representative container glass batch and melted. Results confirm that briquette batch additions can provide equivalent final glass composition, optical absorption characteristics and redox to briquette-free batches, supporting their industrial uptake.

Densification of Thermally Treated Energy Cane and Napier Grass

Densification of thermally treated energy crops by torrefaction is required to increase the bulk density and to reduce the handling, transport, and storage cost for bioenergy applications. In this study, we investigated the densification characteristics of thermally treated energy cane and napier grass grown on marginal lands at various applied forces and binder levels. The addition of starch (0, 10, and 15%) and lignosulfonate (0, 5, and 10%) was examined to enhance the strength and durability of raw and torrefied briquettes, respectively. Although the use of starch binder relatively increased the bulk density, it did not improve the hardness and durability of untreated energy crop briquettes. The addition of 10% lignosulfonate binder increased the torrefied briquette density of up to 11% for energy cane and up to 38% for napier grass and decreased the compression energy by up to 35% for both samples. Moreover, the hardness (compressive resistance) was tripled, and the durability was relatively improved for both torrefied briquettes. The increase in applied force not only increased the bulk density but also increased the specific energy required for densification. However, there was no substantial change in hardness and durability when the compression force was increased from 15 to 20 kN for all samples. In overall, densification of thermally treated energy crops is required, and the quality of the briquettes can be improved by the use of appropriate binders for efficient handling, transport, and storage.

Torrefaction of densified empty fruit bunches with addition of plastics waste

ABSTRACTThe techniques of briquetting and torrefaction were applied to a mixture of pulverized empty fruit bunches (EFB) and shredded high-density polyethylene (HDPE) plastics with a weight ratio of 85:15. The briquettes, produced under controlled conditions, were torrefied at various torrefaction temperatures from 225 to 300°C for 30 min with a constant nitrogen flow rate of 1 L/min. The results indicate that the moisture content is reduced and calorific value is significantly improved due to torrefaction treatment. In addition, the compressive strength of the torrefied briquettes is also enhanced by the torrefaction treatment, thus revealing the important role of HDPE plastics as a good binding agent after the treatment. However, the density of the torrefied briquettes decreased with an increase in temperature. The ash content of the briquettes torrefied at 225 to 275°C can be considered competitive if compared to that of conventional solid fuels (< 5.8%). The physical and combustion properties of the torrefied briquettes are strongly affected by torrefaction temperature and mixture composition. Meanwhile, torrefaction at 300°C is not favourable due to significant physical degradation.

Effects of operating parameters on maize COB briquette quality

Briquetting is considered as one of the pre-treatment methods available for producing uniform sized and moisture content feedstock which is easy to handle, transport and store. The quality of briquettes in terms of density and durability depends on the physical and chemical properties of the feedstock and briquetting conditions. In this study, the effect of compacting pressure, temperature, moisture content, and particle size on the properties of briquettes for thermochemical applications were investigated. It was found that density, impact resistance, and compressive strength significantly increased with increasing compacting temperature (20–80 °C) and compacting pressure (150–250 MPa). However, increasing moisture content and particle size had a negative impact on briquette quality. The results showed that there was a strong interaction between briquetting parameters with the interaction between moisture and temperature significantly affecting both briquette density and mechanical strength. Briquettes with high density and durability/mechanical strength required to meet quality certification standards could be obtained with course ground material (<4 mm) from relatively low moisture content feedstock (7–8%) with pressure of 200–250 MPa and a compacting temperature of 80 °C.

Optimization of binder addition and particle size for densification of coffee husks briquettes using response surface methodology

The present research focuses on establishing the optimum conditions in converting coffee husk into a densified biomass fuel using starch as a binding agent. A Response Surface Methodology (RSM) approach using Box-Behnken experimental design with three levels (-1, 0, and +1) was employed to obtain the optimum level for each parameter. The briquettes wereproduced by compressing the mixture of coffee husk-starch in a piston and die assembly with the pressure of 2000 psi. Furthermore, starch percentage, pyrolysis time, and particle size were the input parameters for the algorithm. Bomb calorimeter was used to determine the heating value (HHV) of the solid fuel. The result of the study indicated that a combination of 34.71 mesh particle size, 110.93 min pyrolysis time, and 8% starch concentration werethe optimum variables.The HHV and density of the fuel were up to 5644.66 calgr-1 and 0.7069 grcm-3,respectively. The study showed that further research should be conducted to improve the briquette density therefore the coffee husk could be convert into commercialsolid fuel to replace the dependent on fossil fuel.

Briquetting of Pine Needles (Pinus roxburgii) and Their Physical, Handling and Combustion Properties

Valorization of pine needles by producing briquettes and identification of optimum levels of densification process parameters based on physical, handling and combustion properties. Experiments were conducted based on orthogonal array test with 16 sets of experiment for 4 levels of 3 independent parameters, size of pine needles, densification pressure and temperature. The briquettes of 35 mm diameter were prepared using a steel mould with well smashed pine needles at 10% (wet basis) moisture content. The dependent parameters were, change in volume, density, durability and compressive strength of briquettes. Grey relational analysis was conducted to identify the optimum levels of independent parameters that minimized the percent change in volume and density of briquettes, and maximized the durability and compressive strength. Grey relational grade that gave equal importance to all the dependent parameters was used as the index for the identification of optimum solution. The pine needles of particle size less than 2 mm, pressure of 9 MPa and temperature of 150 °C was found to be optimum for the production of briquettes, with densification pressure having the highest influence on quality of briquettes. The briquettes produced had calorific value of 17.56 MJ kg−1, density of 1228 kg m−3 and compressive strength of 7.05 MPa. The briquettes were used in an updraft gasifier to generate producer gas which had calorific value of 4.24 MJ Nm−3. It took 12 min to produce flammable gas. The gas from the gasifier can be burnt using specially designed burners in furnaces. The optimum briquetting process parameters identified can be used for the large scale production of briquettes from pine needles at the industrial scale. This will add value to the pine needles, and reduce the risk of forest fire, carbon emissions, greenhouse gas effects and the environmental pollution to a great extent.

Torrefaction of densified mesocarp fibre and palm kernel shell

Abstract Mesocarp fibre and palm kernel shell (PKS) are widely used as fuels for boilers at palm oil mills to generate electricity. In the present study, the PKS and mesocarp fibre were densified under a controlled condition in prior to torrefaction process. Then, the briquettes were torrefied with various temperatures of 250–300 °C, residence time of 40 min and nitrogen flow rate of 1 l/min. In general, the torrefied mesocarp fibre briquettes were successfully produced regardless of torrefaction temperature, whereas the production of torrefied PKS briquettes was only feasible for torrefaction temperature of 250 °C, but the outer surface still remained brittle. The results show that an increase in torrefaction temperature causes a decrease in relaxed density and compressive strength of the torrefied mesocarp fibre briquettes. In terms of combustion properties, an increase in torrefaction temperature causes an increase in gross calorific value, fixed carbon content and ash content while volatile matter decreases. Besides, energy density of the torrefied mesocarp fibre briquettes does not change significantly with respect to the torrefaction temperature. Finally, the gross calorific value and moisture content were found to fulfill the requirements for commercialization as stated by international standards.

Development of the compaction machine for the production of new shapes of pressed biofuels

Briquettes and especially pellets became the fuel of the 21st century. These are pressed biofuels made from the biomass which have the required heat, shape, size, density and mechanical properties. Today, these pressed biofuels are made in the form of a block, cylinder, n-angle octagonal, either without or with the holes. Several analyses confirm that neither a block, nor the cylinder is the optimal shape for the production of pressed biofuels, both in terms of the production, storage, automated transport in the combustion process and the optimum combustion process. For this reason, we began to analyse different shape, size, density and mechanical properties of briquettes and pellets. In the first part of this article, the biofuel is described from these points of view. The result of this analysis is the new optimized spheroid shape of the pressed biofuels. The goal of the second part of the article is the construction design of a new compacting machine for manufacturing of the optimized shape of the compacted piece. The task is demanding due to the fact that in comparison to the production of cylindrical or square-shaped compacted pieces, the manufacturing of ‘quasi-spherical’ compacted pieces is discontinuous. Furthermore, unlike the standard types of compaction presses which compact the material between the two cylinders, it is necessary to hold the compacted piece for certain time under high pressure and at the high temperature. In this way, the lignin contained in compacted raw material becomes plastic and no further binding material needs to be added. The kinematics of a new compactor was therefore divided into two stages- ‘the stage of compacting’ and ‘the stage of load bearing capacity. This article describes an innovative and patent protected principle of compactor construction. The prototype of a designed machine has already been produced in our department. The first test results of this machine production as described in the conclusion of the paper confirm that kinematics and compactor construction were both correct.

Foam Glass Production from Waste Glass by Compression

The authors have identified the impact of the glass mixture briquetting process parameters (milling method, dispersibility, particle size distribution, particle form and compression parameters) on the performance characteristics and the physical and chemical properties of foam glass. It was demonstrated that briquette density increasing contributes to achieving a lower average density of foam glass. It was proven that briquettes produced from multifractional powders are characterized by a higher density than those produced from powders with a limited range of particle size distribution.

Investigation on the effective thermal conductivity of typical Pidgeon process briquette with a combined model

Experiments were conducted on the specific heat and thermal conductivity of a calcined dolomite briquette, a ferrosilicon sample, and a pre-reduction Pidgeon-processed briquette. The laser flash method was used in the measurement of thermal conductivity. Based on the results, a combination of the Series and Maxwell–Eucken 2 models was deduced to fit the effective thermal conductivity of a Pidgeon-processed briquette, which was demonstrated by an analysis of the briquette microstructure. In contrast to previous studies, the proposed study provided specific measured values of briquette density, specific heat, and thermal conductivity, which could be used in the calculation of the Pidgeon process. Moreover, this study offers new potential for the improvement of the numerical simulation accuracy of the Pidgeon process.

Thermal Properties of Green Fuel Briquettes from Residue Corncobs Materials Mixed Macadamia Shell Charcoal Powder

The objective of this research was to produce green fuel briquettes from corncobs by adding macadamia shell charcoal powder. The study was sectioned into 3 parts: 1) Quality improvement of green fuel briquettes by adding macadamia; 2) Fuel property analysis based on ASTM standards and thermal fuel efficiency; and 3) Economics appropriateness in producing green fuel briquettes. This research produced green fuel briquettes using the ratio of corncobs weight and macadamia shell charcoal powder in 100:0 90:10 80:20 70:30 60:40 and 50:50 and pressing in the cold briquette machine. Fuel property analysis showed that green fuel briquettes at the ratio 50:50 produced maximum heating values at 21.06 Megajoule per kilogram and briquette density of 725.18 kilograms per cubic meter, but the percent of moisture content, volatile matter, ash, and fixed carbon were 10.09, 83.02, 2.17 and 4.72 respectively. The thermal efficiency of green fuel briquettes averaged 20.22%. Economics appropriateness was most effective where the ratio of corncobs weight to macadamia shell charcoal powder was at 50:50 which accounted for the cost per kilogram at 5.75 Baht. The net present value was at 1,791.25 Baht. Internal rate of return was at 8.62 and durations for a payback period of investment was at 1.9 years which was suitable for investment.

Effects of Compressing Pressure on Briquettes Made from Woody Biomass

Biomass, in particular wood, has become a fundamental renewable energy source that can replace fossil fuels in many applications, from eating to electricity production. Wood chips are one of the most popular biomass fuel in latest cogenerating plants and in small heating systems. This fuel has low bulk density and needs large volumes in handling and transport operations. These obstacles, common to many biological residues, can be overcome by densification. This study reports the effects of the compressing pressure on the demand of energy required in briquetting, final bulk density and durability of briquettes manufactured from wood chips. An hydraulic press was used to produce briquettes in controlled conditions. Five pressure levels (20, 30, 50, 80 and 110 MPa) and three different types of wood chips (PC - hybrid poplar, CC - chestnut, and MC - mixture of spruce white pine) were investigated. The study shows that the different pressures adopted significantly affect the specific compression energy, the final density and the durability of the compacted samples. Equations were developed to predict compact density and the specific compression energy required by the densification process. The specific compression energy values obtained in this study (18-58 kJ kg-1) were significantly lower than the specific energy required to manufacture pellets made from biomass feedstock (typically 19-90 kJ kg-1). Furthermore, chestnut wood chips with pressure at 110 MPa resulted in the maximum briquettes bulk density and durability.

Production and characterization of smokeless bio-coal briquettes incorporating plastic waste materials

Abstract Sub-bituminous coal from Okaba mine in Kogi State, Nigeria and locally available plastic and bio-waste materials (used sachet water bags, polythene bags, saw dust and maize husk) were partially carbonized, pulverized and used in varying proportions with limestone dust, cassava flour and laterite as binders for the production of solid fuel briquettes. The briquettes were characterized by testing for porosity index, briquette density, compressive strength, ignition and heating efficiency, volatile matter, calorific value, moisture and ash contents using ASTM and DIN standards. The gross calorific values of the briquettes were determined and their fuel properties of burning rate, power output and specific fuel consumption were as well measured. The briquette ash was analysed by X-ray florescence spectrometry (XRF). However, all the briquette ash samples were found to remain intact as a block without collapse after burning. Results of the briquette characterization showed that the briquettes produced with the compositions: 20–70% coal, 2–8% limestone, 10% plastic waste, 2.5–10% cassava flour and 10–60% biomass were of medium to high quality in terms of burning and cooking characteristics, smokelessness, environmental friendliness, binding and mechanical strength. These characteristics suggest that the briquettes produced are good alternative to fuel wood for out-door and in-door cooking and for mitigation of deforestation, desertification and environmental pollution and degradation. Recycling of the plastic wastes into refuse-derived fuel by incorporation in the production of these bio-coal briquettes shows great promise and could be considered as part of waste management options especially in the developing countries.

PHOSPHORUS FERTILIZATION AND HARVEST INTERVALS INFLUENCE ENERGETIC AND PHYSICAL PROPERTIES OF BRIQUETTES AND LARGE BRANCHES OF MATE

ABSTRACT In mate crop, the commercial part consists of leaves and thin branches, while the large branches (LB) are considered unused residues and left in the field, although they may have potential for use as energy. The objective of this paper was to evaluate the influence of phosphorus fertilization and harvest interval in productivity of mate large branches and in their physical and energetic properties, as well as in derived briquettes. In a seven-year-old plantation, doses of 0, 20, 40, 80, 160 and 320 kg.ha-1 of P2O5 were applied considering harvest intervals of 12, 18 and 24 months. Dry mass, average diameter, P content, and physical and energetic properties of LB were determined. With LB, after its transformation into particles and briquetting, physical and energetic properties were determined, as well as P availability in soil. The phosphorus fertilization increased LB productivity in larger harvest intervals, increasing the amount of energy produced per unit of area, but did not change basic density and gross calorific value of wood. Mate harvest intervals did not affect the apparent density and calorific value of briquettes produced by LB. LB harvested at intervals of 18 and 24 months produced wood with higher basic density and gross calorific value. LB or briquettes have adequate energetic and physical properties, being technically a plant residue with great potential for use as energy.

The Infiltration of Lubricants into a Porous Briquette, When Compacting

The migration of the boundary layer of lubricant into a porous briquette during compacting is investigated. It is found out that the density of briquettes compacted of a mixture of iron and graphite powders with the addition of animal fat hardly increases with increasing holding under the load, while the ejection pressure increases substantially. It is assumed that the ejection pressure increases due to the infiltration of a lubricant (from the layer between briquette and die wall) into the pores of the briquette. This leads to thinning disrupting the continuity of the lubrication layer and, accordingly, to increasing the external contact friction. The conducted studies allow not only predicting the behavior of viscous lubricants, but also enhancing the possibilities of impregnating the briquettes sintered under high pressure in the die in vacuum.

Biosolids and microalgae as alternative binders for biomass fuel briquetting

Binders can be employed to improve the particle adhesion, compressive strength, abrasion resistance and energy content of densified biomass, such as briquettes. They may also reduce the energy cost of producing such briquettes, by reducing the compaction pressure, conditioning temperature and the wear on production equipment.This study explored and compared the effects of three different binders, including starch, enhanced treated biosolids and microalgae, on density, durability, energy content and combustion characteristics of fuel briquettes produced from blends of rice husks, corn cobs and bagasse, in a multilevel factorial design experiment.Briquettes had relaxed unit densities of 1.9–3.3 times the loose biomass bulk density, and were stronger than briquettes from the individual materials, with an average unconfined compressive strength of 125kPa. An unconfined compressive strength of 175kPa was achieved for a 2:4:1 blend of rice husks, corn cobs and bagasse with the microalgae binder at a compaction pressure of 31MPa. Statistical analysis of the results showed that the addition of biosolids and microalgae binders significantly improved briquette density, while the addition of starch reduced briquette density, and biosolids reduced briquette strength.Of all the briquettes produced with the three binders, those containing the microalgae binder were found to be most durable, with a higher energy value, slower mass loss during briquette combustion, and a higher afterglow time. Since microalgae may be grown using CO2 from biomass combustion, discovery of their advantages as a binder in briquetting is particularly welcome.

Pre-treatment of oil palm fronds biomass for gasification

Oil Palm Fronds (OPF) has been proven as one of the potential types of biomass feedstock for power generation. The low ash content and high calorific value are making OPF an attractive source for gasification. The objective of this study is to investigate the effects of pre-treatments of OPF residual on gasification. The pre-treatments included the briquetting process and extensive drying of OPF which are studied separately. In briquetting process, the OPF were mixed with some portions of paper as an additives, leaflets, and water, to form a soupy slurry. The extensive drying of OPF needs to cut down OPF in 4–6 cm particle size and left to dry in the oven at 150°C for 24 hours. Gasification process was carried out at the end of each of the pre-treated processes. It was found that the average gas composition obtained from briquetting process was 8.07%, 2.06%, 0.54%,and 11.02% for CO, H 2 , CH 4 , and CO 2 respectively. A good composition of syngas was produced from extensive dried OPF, as 16.48%, 4.03%, 0.91%,and 11.15% for CO, H 2 , CH 4 , and CO 2 contents respectively. It can be concluded that pre-treatments improved the physical characteristics of biomass. The bulk density of biomass can be increased by briquetting but the stability of the structure is depending on the composition of briquette formulation. Furthermore, the stability of gasification process also depended on briquette density, mechanical strength, and formulation.

Density, Shatter Index and Heating Value of Briquettes Produced from the Leaves of Terminalia Mentalis and Sawdust of Daniela Oliveri

This study investigated some qualities of briquettes produced from the leaves of Terminalia mentalis and sawdust of Daniela oliveri as alternative to the conventional fuelwood resources used for domestic cooking. The leaves of Terminalia mentalis and sawdust of Daniela oliveri was collected and sundried to equilibrium moisture content. The samples were sieved into uniform fractions and used to produce briquettes at 25% of starch to sample as binder. The experimental design was a 2 x 3 factorial in Completely Randomised Design (CRD). Densities, Shatter index and Combustion related properties such as % moisture content, % volatile matter, % fixed carbon, % ash content and Specific heat of combustion (Heating value) were investigated from the produced briquettes. Terminalia mentalis briquettes recorded a highly significant relaxed density of 0.668 g/cm3 in seven (7) days. Terminalia mentalis briquettes recorded a higher weight loss of 2.00% and lower shatter resistance of 98% which was significantly lower than Terminalia mentalis + Daniela oliveri briquettes with weight loss of 0.02% and higher shatter resistance of 99.98%. The specific heat of combustion value ranged from 9704.0 kcal/kg to 11053.0 kcal/kg for Terminalia mentalis and Terminalia mentalis + Daniela oliveri respectively. The percentage Ash content was significant, for Terminalia mentalis briquettes which recorded a higher %Ash content of 12.56% , 30.93% fixed carbon and 56.52% volatile matter while there was no significant difference in %moisture content. The effect of particle size also showed that there was no significant difference in % Volatile matter and heating value. The relatively high heating values of the briquettes indicate that the materials can be a very good alternative source of energy for cooking.

Gasification: An alternative solution for energy recovery and utilization of vegetable market waste.

Vegetables waste is generally utilized through a bioconversion process or disposed of at municipal landfills, dumping sites or dumped on open land, emitting a foul odor and causing health hazards. The presents study deals with an alternative way to utilize solid vegetable waste through a thermochemical route such as briquetting and gasification for its energy recovery and subsequent power generation. Briquettes of 50 mm diameter were produced from four different types of vegetable waste. The bulk density of briquettes produced was increased 10 to 15 times higher than the density of the dried vegetable waste in loose form. The lower heating value (LHV) of the briquettes ranged from 10.26 MJ kg-1 to 16.60 MJ kg-1 depending on the type of vegetable waste. The gasification of the briquettes was carried out in an open core downdraft gasifier, which resulted in syngas with a calorific value of 4.71 MJ Nm-3 at the gasification temperature between 889°C and 1011°C. A spark ignition, internal combustion engine was run on syngas and could generate a maximum load up to 10 kWe. The cold gas efficiency and the hot gas efficiency of the gasifier were measured at 74.11% and 79.87%, respectively. Energy recovery from the organic vegetable waste was possible through a thermochemical conversion route such as briquetting and subsequent gasification and recovery of the fuel for small-scale power generation.

Briquetting Metallurgical Lime Screenings and Parameters Making it Possible to Improve Process Efficiency

Results are given for roll briquetting of metallurgical lime. Experimental results are obtained in laboratory presses and industrial briquetting units. Dependences are obtained for briquette density on compaction pressure and process productivity with different roll briquetting parameters. Technology and equipment presented in the work for lime briquetting make it possible to prepare high quality briquettes for the metallurgical industry. Results obtained are used in developing production briquetting processes and planning equipment.