Increasing Compaction Pressure Research Articles

Research on the Influencing Factors of the Void Volume of Insoluble Sediment in Salt Cavern Gas Storage

Utilizing voids of insoluble sediment (IS) to store gas is an effective way to improve the efficiency of salt cavern gas storage (SCGS) in China. In this study, a suitable method for predicting the void volume of insoluble sediments (VVISs) is established. This study explores three key factors affecting the VVISs through laboratory experiments. Firstly, in order to make the experimental results more in line with production realities, an analysis of the characteristics of IS in X SCGS was conducted to provide a basis for setting parameters for subsequent experiments. Secondly, experimental setups and methods for measuring the VVISs were designed. Finally, the experimental results were used to predict the VVISs in on-site cavity wells. The results indicate that the higher the proportion of quartz, illite, and large-grain particles in IS, the larger the VVISs. Under different parameters, the VVISs can account for approximately 10–40% of the IS accumulation volume. Different particle sizes can cause a variation of approximately 5–30% in the VVISs, while different mineral compositions can result in a difference of 6–23% in the VVISs. With increasing compaction pressure, the VVISs can decrease by around 5–80%. The prediction of the VVISs in on-site cavity wells shows a high degree of fit with empirical algorithms. This study can provide a reference basis for the utilization of the void space of IS in SCGS.

Characterization of a functionally graded material produced using a new designed blender

Abstract One of the techniques widely used for fabrication of FGMs (Functionally Graded Materials) is powder metallurgy. However, producing a FGM with smooth gradient in its constituents mixture has remained a challenge yet to be met. The purpose of this research is design and manufacturing a blender for producing a functionally graded material with smooth gradient of its constituent materials. The blender was used to mix magnesium and titanium dioxide to produce Magnesium/titanium dioxide FGMs. The powder mixture was then compacted by Instron, drop hammer, and split Hopkinson bar at 600 °C. The microstructure and relative density of the functionally graded samples fabricated at different strain rates were studied in this work. SEM images clearly demonstrated a continuous and functional distribution of Mg and TiO2 particles in the produced FGM samples. It was also shown that increasing the compaction loading rate resulted in a higher relative density in the FGM samples. The maximum relative density (92%) was observed for the samples produced by Hopkinson bar. This level of density was 7% and 17% higher than the densities of the samples fabricated using drop hammer and Instron, respectively. The improvement of relative density in dynamic compaction methods is attributed to the increased compaction pressure and process being adiabatic.

Preparation and Compression Behavior of High Porosity, Microporous Open-Cell Al Foam Using Supergravity Infiltration Method.

By employing a method that combines a NaCl compacting template and supergravity infiltration, open-cell aluminum (Al) foam with varying porosities was prepared. The Al foam fabricated has a pore size of 400 µm and porosity ranging from 0.72 to 0.88. The experimental results indicate that, with an increase in compaction pressure during the NaCl compacting process, the porosity of the foam Al increases and the struts become finer. As the gravity coefficient increases, the density and integrity of the foam Al also increase. Due to the effectiveness of supergravity in overcoming the infiltration resistance between the NaCl preform and molten Al, the supergravity infiltration method holds promise as a practical new technique for fabricating high-porosity open-cell Al foam.

Effect of compaction pressure on cold compaction of AA2024 swarf generated during milling operation

The solid-state recycling of aluminium swarf is a promising alternative to the conventional practice of remelting, which can lead to the loss of aluminium. The compaction process is an important step in the solid-state recycling of aluminium swarf. This study investigated the effect of cold compaction pressure on the material behaviour, density, and microstructure of compacted AA2024 machining swarf. The milling swarf was initially cleaned and chemical composition analysis was carried out. Morphology of swarf particle exhibited a wavy and straight regions attributable to milling conditions. The swarf then compacted at room temperature for 3 different pressure level viz. 1000, 1500, and 2000 kgf/cm2. The results showed that the density of the compacts increased with the increase in compaction pressure, reaching a value of 85% of the density of AA2024 at a pressure of 2000 kgf/cm2. Microstructure was analysed using scanning electron microscope to understand the bonding at the the swarf-swarf particle boundary. Vickers hardness results indicated that the hardness values of the compacted specimens also increased slightly with increasing compaction pressure. The overall combination of factors viz. plastic deformation, reorientation, rupturing of oxide layers, and mechanical interlocking contributes to the strength and compaction of swarf particles when subjected to higher compaction pressure used in this study. Further studies are in progress to improve the densification of the compacted specimens and to evaluate their suitability for extrusion applications.

A comparative study on lightweight and dense periclase-magnesium aluminate spinel refractories from industrial preparation

Lightweight design and preparation of refractories can promote the energy saving and emissions reduction for the working linings of high temperature furnaces. In this work, two lightweight periclase-magnesium aluminate spinel refractories were prepared by using microporous aggregates under the industrial production condition and compared with commercial dense refractories. The effects of the microporous aggregates and compaction pressure on their microstructures and properties were studied. A comparison of the results indicates that the flexural strengths of the lightweight specimens were enhanced from 3.7 MPa to 6.8 MPa, and the thermal conductivities were reduced significantly, better microporous aggregate/matrix interface structures were formed in the lightweight specimens due to the pore structures in microporous aggregates. Meanwhile, increasing compaction pressure from 120 MPa to 160 MPa negatively affected the thermal shock resistance and refractoriness under load of the lightweight specimens. In summary, the lightweight specimen made using a compaction pressure of 120 MPa exhibited higher strength, excellent thermal shock resistance, lower thermal conductivity(3.47 W/m·K at 1200 ℃) and high refractoriness under load (1661 ℃), which can meet the requirements for the upper transition zone and burning zone of cement rotary kilns.

Mechanical characterization of high volume fraction Al7075-Al2O3 composite fabricated by semisolid powder processing

The mechanical properties and physical characteristics of aluminum alloy composites can be significantly improved by adding reinforcing phases. However, the high loading of the reinforcement phase in Al7075-Al2O3 composites has not been thoroughly studied. In this work, a combination of semisolid metal powder processing and powder metallurgy is used to process and manufacture Al7075-Al2O3 composites with a high reinforcement fraction of > 40 vol.%. The effects of processing parameters on the microstructures and mechanical properties of the composite material are discussed in detail. The loading limits of the high volume Al2O3 reinforcement in Al7075 composites are identified and linked to the processing parameters. A methodology is introduced to estimate the consolidation temperature of Al7075 alloy using compaction testing. Al2O3 particles (the average particle size of 120 µm) were mechanically milled with Al7075 powder (the average particle size of 20 µm) for 10 min and 5 h using a high-energy planetary ball mill. The mixture was then compacted in the semisolid state at 615 °C under the compaction pressures of 50 MPa and 100 MPa. By increasing the milling time from 10 min to 5 h, the deformation of aluminum powders and the fracture of Al2O3 reinforcement particles occur, restricting the loading limit of reinforcement. The milling time also shows a dominant effect on the powder morphology, microstructure, and mechanical properties of Al7075-Al2O3 composites. Increasing compaction pressure from 50 to 100 MPa significantly improved the compressive strength of the composite from 218 to 652 MPa. Al7075-Al2O3 composite with 40 vol.% of reinforcing phase exhibits the highest hardness of 198.2 HV and 96.9% relative density when it is milled for 5 h and compacted at 100 MPa. However, this composite shows the highest strength of 652 MPa when it is milled for 10 min. By increasing the reinforcing phase to 50 vol.% and 60 vol.%, the hardness, density, and compressive strength of composites decreased. The composites with 60 vol.% of reinforcing phase appeared overloaded. Results show that semisolid metal powder processing has huge potential for the fabrication of high loading Al2O3 in Al7075 matrix with near theoretical density.

Effects of heat treatment and compaction pressure on the microstructure and magnetic properties of core-shell structured FeSiBNbCu/SiO2 soft magnetic composites

Here, the FeSiBNbCu/SiO2 soft magnetic composites (SMCs) with core-shell structure were successfully designed and fabricated using nanocrystalline powders as seeds and SiO2 were grown by sol-gel technique onto the surface of the seed particles. We systematically investigated the influences of annealing temperature and compaction pressure on the micromorphology, chemical structure and soft magnetic properties of the SMCs. The results demonstrate that a large number of submicron-sized SiO2 particles are uniformly deposited on the surface of the powders, which significantly improves the insulating characteristics between the magnetic powders. Also, the effective permeability μe increases and the core loss Pcv decreases with increasing annealing temperature from 480 °C to 550 °C, which is attributed to the relaxation of internal stress and the increase of volume fraction of α-Fe(Si) grains. Furthermore, an increase in compaction pressure effectively increases the densification and reduces the porosity, which facilitates a denser microstructure. Under the combined effect of optimal annealing temperature and compaction pressure, the SMCs exhibit high μe of 84 and low Pcv of 174 kW/m3 at 50 kHz for Bm = 0.1 T. This work provides a new strategy for the construction of core-shell structure and a comprehensive understanding of the relationship between process parameters and microstructure, which is of great guiding significance for industrial production.

A work done approach on analyzing the effects of densification parameters on tapered screw extruders

Densification is the process of compacting bulk material to increase its physical and energy density. One way of densification is by using screw extruders. Yet, sufficient theoretical studies have not been carried out on the densification parameters for a tapered screw. In this study, a mathematical model for investigating the effect of the operational parameters on a tapered screw has been studied by analyzing the work balance on the plug along the tapered screw channel. By using the taper angle, screw pitch, and barrel friction coefficients as control variables, a mathematical model for the pressure gradient, volumetric throughput, and output density was established. The velocity profile of the plug along the screw channel was measured to determine the volumetric throughput. The final model for the pressure gradient along the axial length of the screw has been approximated by Runge-Kutta fourth order approximation model in the python programing environment. From the results, an increase in screw length, screw taper angle, and barrel friction coefficient has been attributed to an increase in compaction pressure. This parameter has also changed for a [Formula: see text] tapper angle, which is primarily due to centrifugal, gravity, and frictional forces acting on the plug. Further investigation into the volumetric throughput and output density has the same effect. According to the analysis, the optimum taper angle has been identified to be between [Formula: see text] and [Formula: see text], which yields the optimum output density without compromising the combustion property of the compacted biomass.

CO2 Curing of Ca-Rich Fly Ashes to Produce Cement-Free Building Materials

In this study, fly ash (FA) compacts were prepared by accelerated carbonation as a potential sustainable building material application with the locally available ashes (oil shale ash (OSA), wood ash (WA) and land filled oil shale ash (LFA)) of Estonia. The carbonation behaviour of FAs and the performance of 100% FA based compacts were evaluated based on the obtained values of CO2 uptake and compressive strength. The influence of different variables (compaction pressure, curing temperature, CO2 concentration, and pressure) on the CO2 uptake and strength development of FA compacts were investigated and the reaction kinetics of the carbonation process were tested by different reaction-order models. A reasonable relation was noted between the CO2 uptake and compressive strength of the compacts. The porous surface structure of the hydrated OSA and WA compacts was changed after carbonation due to the calcite formations (being the primary carbonation product), especially on portlandite crystals. The increase of temperature, gas pressure, and CO2 concentration improved the CO2 uptake levels of compacts. However, the positive effect of increasing compaction pressure was more apparent on the final strength of the compacts. The obtained compressive strength and CO2 uptake values of FA compacts were between 10 and 36 MPa and 11 and 13 wt%, respectively, under various operation conditions. Moreover, compacts with mixed design (OSA/LFA and WA/LFA) resulted in low-strength and density compared to the single behaviour of OSA and WA compacts, yet a higher CO2 uptake was achieved (approximately 15% mass) with mixed design. The conformity of Jander equation (3D-diffusion-limited reaction model) was higher compared to other tested reaction order models for the representation of the carbonation reaction mechanism of OSA and WA. The activation energy for OSA compact was calculated as 3.55 kJ/mol and for WA as 17.06 kJ/mol.

Upgrading Characteristics of Empty Fruit Bunch Biopellet with Addition of Bintaro Fruit as Co-firing

The low density of mass and energy are the main reason for the underutilization of great potential of Empty Fruit Bunch (EFB) as a raw material of alternative and renewable fuels. The using of bintaro fruit as co-firing and treatment of torrefaction – densification processes were believed to increase the density of mass and energy of the EFB biopellet. This study aims to determine the effect of residence time, compaction pressure, and addition of bintaro fruit to the characteristics of EFB biopellet according to ISO 17225-6 standards. Biopellet manufacture was carried out two processes sequence, namely the torrefaction process and the densification process. The torrefaction process was carried out at 275oC with residence time variations 30, 45, and 60 minutes. The densification process was carried out without binder with compaction pressure variations 30, 40, and 50 bar. The addition of bintaro fruit was intended as co-firing of EFB at a ratio 70:30. The best characteristics of biopellet were obtained under conditions of 60 minutes residence time and 50 bar compaction pressures with 3.00% of moisture content, 7.90% of ash content, 8.70% of volatile content, 80.40% of fixed carbon content, 4719.59 cal/gr of heating value, and 1.28 gr/cm3 of density. Characteristics of moisture content and volatile content decreased while ash content, fixed carbon content, and heating value increased with increasing residence time. Characteristics of density increased with increasing compaction pressure. Characteristics of proximate and heating value increased while density properties of biopellet decreased with the addition of bintaro fruit as co-firing.

Effect of Pressure Load on the Physical Properties of ZTA-TiO<sub>2</sub>-Cr<sub>2</sub>O<sub>3</sub>

ZTA is considered as one of the most popular ceramic composites that are used for cutting tools due to their excellent properties. Consistent efforts should be expanded to achieve improvements in toughness and strength, and thus help them achieve a longer tool life. However, powder compaction process has been found to be a limiting factor in the production of a defect-free ceramic pellet where the green product often ruptures immediately after the compaction process or sintering process. This may be contributed by uneven distribution of pressure load, thus affecting the particles packing and properties of final product. As a solution, the present work aims to study the effect of different compaction pressure on the physical properties of ZTA-TiO2-Cr2O3 ceramic composite to establish a defect-free cutting insert. The samples were fabricated by solid state processing, subjected to pressure loads varied from 200 MPa-350MPa, followed by sintering at 1600°C for 1 hour. The sintered samples were characterized accordingly. The results showed significant enhancement in density and hardness with increasing compaction pressure from 200 MPa to 300 MPa. On the other hand, further increment of pressure deteriorates the properties of the samples. These were due to the excessive external pressure which caused a very tight compaction in the mold, resulted in elastic expansion of the compact and sliding of particles as the pressure is removed. In conclusion, ZTA-TiO2-Cr2O3 subjected to 300 MPa compaction pressure showed the most optimal properties with the highest density (4.58 g/cm3) and hardness (2001 HV).

Synthesis of Spinel-Hydroxyapatite Composite Utilizing Bovine Bone and Beverage Can

Spinel-based hydroxyapatite composite (SHC) has been synthesized utilizing bovine bones as the source of the hydroxyapatite (HAp) and beverage cans as the aluminum (Al) source. The bovine bones were defatted and calcined in the air atmosphere to transform them into hydroxyapatite. The beverage cans were cut and milled to obtain fine Al powder and then sieved to obtain three different particle mesh size fractions: +100#, −140# + 170#, and −170#, or Al particle size of >150, 90–150, and <90 µm, respectively. The SHC was synthesized using the self-propagating intermediate-temperature synthesis (SIS) method at 900 °C for 2 h with (HAp:Al:Mg) ratio of (87:10:3 wt.%) and various compaction pressure of 100, 171, and 200 MPa. It was found that the mechanical properties of the SHC are influenced by the Al particle size and the compaction pressure. Smaller particle size produces the tendency of increasing the hardness and reducing the porosity of the composite. Meanwhile, increasing compaction pressure produces a reduction of the SHC porosity. The increase in the hardness is also observed by increasing the compaction pressure except for the smallest Al particle size (<90 µm), where the hardness instead becomes smaller.

Investigations on compressive strength of titanium diboride and graphite reinforced Magnesium Matrix Composites

Magnesium matrix composites are widely used materials because of its excellent properties and low weight. In this work, the magnesium-based composites have been fabricated using powder metallurgy (PM) route. The compressive strength (CP) of the Mg-1wt.% Gr- 6 wt.% T1B2 composites were studied and reported. The effect of the compaction pressure (P), sintering temperature (T) and sintering time (h) on the compressive strength was analyzed. The increase in compaction pressure increases the mechanical properties of the composites. The optimum level of parameters for the high CS is that, A3B3C3 that is higher Pressure, temperature and time produced the high strength composite. ANOVA showed the compaction pressure is the highly influenced parameter with the F value of 180.85. Sintering time is the least contributing factor for the response for the present study.

Properties and microstructure of CO2 activated binder produced by recycling phosphorous slag

This study examined the feasibility of producing CO2 activated binder by recycling phosphorous slag (PHS). The PHS specimen was shaped by compaction in view of its non-hydraulic activity at room temperature. Its reaction products, properties, including compressive strength and CO2 uptake, and microstructure were evaluated by multiple measurements. Results showed that CO2 activated binder could be produced by recycling phosphorous slag. The compressive strength of PHS specimens increased significantly up to 171.0 MPa after CO2 curing and presented an increasing trend with the increase of compaction pressure. The carbonation products of PHS were calcite and silica gel. CaCO3 formed firstly in spherical amorphous phase and then spindle calcite. The carbonated PHS particles showed a three-layer microstructure: unreacted core surrounded by a rim of silica gel with calcite filling up the spaces between PHS particles. The porosity and pore size decreased greatly after carbonation and with the higher compaction pressure. The degree of carbonation decreased with the increase of compaction pressure, while compressive strength increased. The improved compressive strength is attributed to the densified microstructure due to carbonation and compaction. CO2 uptake analysis shows that 1 t PHS can take up 110.9 kg CO2, presenting the potential of PHS to be used as a CO2 activated binder.

Physical and Mechanical Behavior of NiTi Composite Fabricated by Newly Developed Uni-Axial Compaction Die

Owing to better mechanical properties and shape memory effect, the NiTi composites fabricated by powder metallurgy are suitable for biomedical implants. However, the excessive porosity and formation of micro-cracks are the major issues related to the NiTi composite. This work focused on developing crack-free dense NiTi composites by newly developed uni-axial compaction die. The work includes the design and manufacturing of uni-axial compaction die. The die was tested by SOLIDWORKS software in a simulated environment. Further, composite samples were successfully fabricated without circumferential micro-cracks at 1910.82 MPa compaction pressure. The effects of compaction pressure on microstructural, densification, and mechanical behavior of NiTi composites were also analyzed. Microstructural characterization shows that the Ni-rich phase increased and the Ti-rich phase decreased with the increase of compaction pressure. The porosity reduces from 17.04 to 8.75% by increasing the compaction pressure from 1273.88 to 1910.82 MPa, and a maximum density of 5.50 g.cm–3 was obtained. The NiTi150 composite has similar Young’s modulus, and compressive strength (6.93 GPa and 94.36 MPa) compared to cortical and cancellous bone. The high compaction pressure also increases the micro-hardness of NiTi composite up to 453.8 HV0.5.

Compaction and Heat Treatment Effects on the Structural and Mechanical Properties of Sintered Fe<sub>3</sub>C-W-Co Alloys

In this article, the 75Fe3C-20W-5Co alloy is developed by the powder metallurgy technique in order to study the microstructure and the mechanical properties obtained after solid phase sintering. The mechanical grinding of the mixture of these Fe3C-W-Co powders lasted 6 hours.The powders were compressed by cold isostatic pressing (CIP) at different compaction pressures (5MPa, 10MPa, 15MPa and 18MPa). The green compacts obtained were sintered at a temperature equal to 1350 °C, followed by a heat treatment at different temperatures (850 °C, 950 °C and 1100 °C). The samples were then cooled in different baths (oil and water). The characterization of this sintered steel alloy was carried out by X-ray diffraction (XRD) and with an optical microscope. The results reveal that the structure of these sintered alloys consisted of the Fe matrix phase and the W-Co solid solution phase. The compaction pressure influences the number and size of the pores. Hardness and wear resistance increase with increasing compaction pressure.

Role of nanopowder agglomerates in forming the structure and properties of ceramic materials

A comparative analysis of agglomerates obtained by spray drying and granulation methods and consolidated materials based on them was carried out. The paper provides the results obtained when studying zirconia nanopowders granulated in water medium with an agar agar additive obtained by chemical precipitation with zirconia partially stabilized by yttrium oxide (2.5 mol.%), and TZ-3Y-E powder manufactured by Tosoh Corp. (Japan) that was prepared by spray drying. Agglomerates as well as microsections and fractures of samples were studied by scanning electron, optical, atomic force microscopy, and Raman spectroscopy. The crack resistance coefficient (K1с) of samples was determined by indenting the polished surface of microsections with a Vickers pyramid. The specific surface of the powders measured by nitrogen thermal desorption during granulation remains unchanged indicating a significant open porosity of agglomerates obtained. With increasing compacting pressure under conditions of semi-dry compaction with an aqueous solution of PVA as a binder, agglomerates and even aggregates of granulated powders are destroyed, K1с increases with increasing compaction pressure and the accompanying material microstructure grinding. Powders agglomerated using spray drying break up much less intensively, K1с does not change with increasing pressure. The studies conducted allow us to agree with the authors pointing to the fractal nature of agglomerates obtained from chemically precipitated nanopowders without the use of spray drying. The use of granulated nanopowders in semi-dry compaction with the application of high pressures makes it possible to destroy not only agglomerates, but also aggregates, and to obtain nanostructured ceramics with grain sizes close to the size of initial particles.

MECHANICAL CHARACTERISTIC STUDY OF COBALT ALLOY PREPARED BY POWDER METALLURGY METHOD

This study was conducted to determine the effect of compaction pressure and sintering temperature variations on the properties of physical, mechanical, and micro cobalt alloy. Manufacture of the cobalt alloy with compositions 63,75%, chromium 30%, molybdenum 5%, manganese 0,5%, silicon 0,5%, and 0,25% nitrogen using powder metallurgy method. Variations of compaction pressure were 339,70 MPa, 396,31 MPa, dan 452,93 MPa, and sintered at temperature 12000C and 130 0C for 2 hours of holding time. Density was increased along with the increasing compaction pressure and sintering temperature (3,9-6,6 g/cm). The hardness was also increased along with the increasing compaction pressure and sintering temperature 205,1-316,2 VHN. XRD results showed that γ phase with fcc structure was formed at the temperature of 12000C and 13000C for all variations of pressure. SEM-EDX results showed that the oxygen content decreased along with increasing compaction pressure and sintering temperature. Based on ASTM F75 hardness standard, the sample with compaction pressure 452,93 MPa and sintered at 13000C was the best cobalt alloy with a hardness value of 316.2 VHN.

Use of Ceramic Waste for the Manufacture of Sintered Parts

This paper evaluated the use of the pitcher, a ceramic waste obtained through the quality process of a sanitary ware industry, in the development of a material for usage in the manufacture of sintered parts. The pitcher was obtained through powder technology and is composed, according to the chemical analysis obtained by X-ray fluorescence spectrometry, of clayey minerals (clay and kaolin), quartz, and feldspar, which may include ceramic rocks such as granite, pegmatite and phyllite; that is, it has proved to be a potential raw material due to the minerals that can still be reused. The pitcher passed through a granulometry-based selection process, sieving about 20kg using the following sieve sequence: 18 MESH, 25 MESH, 30 MESH, 120 MESH and 400 MESH; with around 70% of the residue being retained in the sieves of 120 and 400 MESH, which were selected to be used in the evaluation. The samples were compacted in a manual press with different pressures, between 300 and 1000 kgf, and after were sintered at a temperature of 1100oC in a resistive furnace. To characterize the material, the apparent and green density, as well as the compressibility curve, were determined to identify the best compression pressure. The microstructure of the test specimen and the pitcher homogeneity were evaluated using Scanning Electron Microscopy (SEM). Both particle sizes presented the typical compressibility curve, in which the density increases with increasing compaction pressure, while the curve slope decreases with increasing pressure. The density increase with the increasing compaction pressure indicates a good densification for the temperatures, independent of the sample granulometry. The sintering porosity decreased proportionally to the particle size in the sintered samples. The analysis showed that the particle size of 400 MESH sintered at 1100oC obtained more porous surfaces, thus indicating a promising future for the manufacture of parts using powder technology, especially for the development of filters.

Upgrading Characteristics of Empty Fruit Bunch Biopellet with Addition of Bintaro Fruit as Co-firing

The low density of mass and energy are the main reason for the underutilization of great potential of Empty Fruit Bunch (EFB) as a raw material of alternative and renewable fuels. The using of bintaro fruit as co-firing and treatment of torre faction – densification processes were believed to increase the density of mass and energy of the EFB bio pellet. This study aims to determine the effect of residence time, compaction pressure, and addition of bintaro fruit to the characteristics of EFB bio pellet according to ISO 17225-6 standards. Bio pellet machine was carried out two processes sequence, namely the torre faction process and the densification process. The torre faction process was carried out at 275°C with residence time variations 30, 45, and 60 minutes. The densification process was carried out without binder with compaction pressure variations 30, 40, and 50 bar. Characteristics of moisture content and volatile content decreased while ash content, fixed carbon content, and heating value increased with increasing residence time. Characteristics of density increased with increasing compaction pressure. Characteristics of proximate and heating value increased while density properties of bio pellet decreased with the addition of bintaro fruit as co-firing.