Research on Purification Technology of Ultra-Large Flake Graphite Based on Alkali-Acid Method

2021 ◽  
Vol 1036 ◽  
pp. 104-113
Author(s):  
Hong Fei Guo ◽  
Bao Chao ◽  
Zeng Qi Zhao ◽  
Ding Nan
Keyword(s):  
Carbon Content ◽  
High Purity ◽  
Raw Materials ◽  
Acid Leaching ◽  
Flake Graphite ◽  
Fixed Carbon ◽  
Fusion Temperature ◽  
Acid Method ◽  
Fixed Carbon Content ◽  
Flake Structure

Graphite is a strategically scarce resource, and the preparation of high-purity graphite is the prerequisite and basis for the application of graphite. In order to determine the optimal purification technology parameters of an ultra-large flake graphite mine pneumatic separation ore with a fixed carbon content of 77.69%, a particle size of mainly 10 to 40 mesh, and main impurities of calcium carbonate, iron oxide and silica , two additional experiments of acid method and alkali method were added on the basis of alkali-acid method, to investigate the purification effect of different technological processes and acid leaching times on graphite raw materials, as well as to analyze the retention extent of different methods and alkali fusion temperature on graphite ultra-large flake structure. The results show that all three methods can increase the fixed carbon content of graphite to above 99%. However, compared with the acid method and the alkali method, the alkali-acid method can obtain high-purity graphite while also better protecting the graphite's ultra-large flake structure. The optimal fusion temperature is 400 °C, the optimal acid leaching time is 30% sulfuric acid thrice and 5% hydrofluoric acid once. After purification, the fixed carbon content of the product exceeds 99.97%.

Research on Purification Technics of some Flake Graphite

2013 ◽  
Vol 753-755 ◽  
pp. 119-123 ◽  
Author(s):  
Shu Fang Ding ◽  
Yan Ping Niu
Keyword(s):  
Carbon Content ◽  
Recovery Rate ◽  
Technology Development ◽  
New Technology ◽  
Experimental Results ◽  
Graphite Flake ◽  
Flake Graphite ◽  
Property A ◽  
Fixed Carbon ◽  
Fixed Carbon Content

Graphite is the very important nonmetallic ore that high and new technology development needs. According to the ore property, a purification technics of some flake graphite was studies. Firstly, the experiment researched the primary grinding fineness condition test, its result showed that grade has good and recovery is more high when coarse grinding fineness-200 mesh is 66.4%. Then on the basic of the test, a closed trial was conducted by five-times-regrinding and six-times-cleaning, the experimental results indicated that the grade of graphite (Fixed carbon content) is 89.48%, recovery rate reached 97.42%, separation index is better. Finally, the analysis of products showed that fixed carbon content of +100 mesh, +200 mesh graphite flake is respectively 92.90% and 90.53%, so we can choose the multi-grade graphite product.

scholarly journals Energetic potential of bamboo culms for industrial and domestic use in Southern Brazil

2016 ◽  
Vol 46 (11) ◽  
pp. 1963-1968 ◽  
Author(s):  
Ailton Leonel Balduino Junior ◽  
Thalles Yurgen Balduino ◽  
Gustavo Friederichs ◽  
Alexsandro Bayestorff da Cunha ◽  
Martha Andreia Brand
Keyword(s):  
Chemical Composition ◽  
Carbon Content ◽  
Calorific Value ◽  
Energy Generation ◽  
Extractive Content ◽  
Fixed Carbon ◽  
Gross Calorific Value ◽  
Bambusa Vulgaris ◽  
Domestic Use ◽  
Fixed Carbon Content

ABSTRACT: This study aimed to determine the energetic quality of the Bambusa vulgaris culms for combustion (in natura) and as a charcoal. Five individuals (culms) of Bambusa vulgaris of 3 years of age were analyzed, gathered in the city of Florianópolis, Santa Catarina. In the in natura culms it was determined the moisture content freshly gathered (39%); basic density (0.624gcm-3); the chemical composition (total extractive content (16.26%) and lignin content (25.76%)); the proximate chemical composition (volatiles content (82.25%); fixed carbon content (15.26%) and ash (2.49%)) and gross calorific value (4571kcalkg-1). In the charcoal, produced in the laboratory, the determined properties were the gravimetric yield (36.40%);the apparent density (0.372gcm-3); volatiles content (27.55%); fixed carbon content (67.32%); ash (5.12%) and gross calorific value (7431kcalkg-1). The Bambusa vulgaris species has potential for use in the energy generation either in natura, as chips for burning in boilers or in the charcoal form for domestic use, it can be used to broaden the base of biomass for energy generation and to replace the timber species of Pinus and Eucalyptus gender used for this purpose in the Southern region of Brazil.

scholarly journals Pemanfaatan Limbah Kulit Kakao Menjadi Briket Arang sebagai Bahan Bakar Alternatif dengan Penambahan Ampas Buah Merah

2019 ◽  
Vol 13 (1) ◽  
pp. 57
Author(s):  
Syarifhidayahtullah Syarif ◽  
Rochim Bakti Cahyono ◽  
Muslikhin Hidayat
Keyword(s):  
Moisture Content ◽  
Carbon Content ◽  
Calorific Value ◽  
Ash Content ◽  
Fruit Pulp ◽  
Volatile Content ◽  
Fixed Carbon ◽  
Shell Waste ◽  
Cocoa Shell ◽  
Fixed Carbon Content

A B S T R A C TThe conversion of cocoa shell waste into char briquettes has been carried out through various methods. However, the product characteristics do not meet the SNI briquettes requirements. Therefore, it is necessary to improve process engineering by mixing cocoa peel waste with red fruit pulp to get char briquettes in order to improve quality of briquette products. This research was carried out through pyrolysis process with temperthwatures up to 500 oC and held for 4 hours. The research objective was to produce char briquettes from cacao pod shell waste with the addition of red fruit pulp and its characteristic test. The study was designed with 2 variables, namely independent variables in the form of char raw material powder that passed 50 mesh sieve, weight ratio of cocoa shell char powder and red fruit pulp char powder (100:0, 70:30, 50:50, 30:70, and 0%:100%), pressure (100 kg/cm2), 10% starch adhesive from raw materials, and briquette diameter of 40 mm. Whereas the dependent variables are the moisture content (%), volatile content (%), ash content (%), fixed carbon content (%), and calorific value (cal/g). The results showed that the process of pyrolysis of char briquettes waste cocoa shell with red fruit pulp can increase its calorific value. The best characteristics of briquette were obtained from mixed briquettes (composition of 30%:70%) with moisture content of 5.63%, volatile content of 18.65%, ash content of 9.45%, fixed carbon content of 66.27%, and calorific value of 6422 cal/g.A B S T R A KPemanfaatan limbah kulit buah kakao menjadi briket arang telah banyak dilakukan melalui berbagai metode tetapi belum memenuhi persyaratan SNI briket arang. Oleh karena itu, perlu diupayakan untuk mendapatkan briket arang yang memenuhi persyaratan SNI. Salah satunya dengan cara mencampurkan limbah kulit kakao dengan ampas buah merah karena ampas buah merah memiliki nilai kalor yang cukup tinggi. Penelitian ini dilakukan melalui proses pirolisis dengan suhu sampai dengan 500 oC  dan ditahan selama 4 jam. Tujuan penelitian untuk memproduksi briket arang dari limbah kulit buah kakao dengan penambahan ampas buah merah serta uji karakteristiknya. Penelitian dirancang dengan 2 variabel, yaitu variabel bebas (independent variable) berupa ukuran serbuk bahan baku arang yang lolos saringan  50 mesh, rasio massa campuran serbuk arang kulit kakao dengan serbuk arang ampas buah merah (100:0, 70:30, 50:50, 30:70, dan 0%:100%), tekanan pengempaan (100 kg/cm2), perekat kanji 10% dari bahan baku, dan diameter briket 40 mm. Variabel terikat (dependent variable) yang diukur yaitu kadar air (%), kadar zat mudah menguap (%), kadar abu (%), kadar karbon terikat (%), dan nilai kalor (kal/g). Hasil penelitian menunjukkan bahwa, dengan melalui proses pirolisis briket arang limbah kulit kakao dengan ampas buah merah dapat meningkatkan nilai kalor-nya. Karakteristik briket terbaik diperoleh dari briket komposisi campuran (30%:70%) dengan kadar air 5,63 %, kadar zat mudah menguap 18,65 %, kadar abu 9,45 %, kadar karbon terikat 66,27 %, dan nilai kalor 6422 kal/g.

scholarly journals THE EFFECT OF BINDER RATIO ON THE PHYSICAL AND COMBUSTION CHARACTERISTICS OF CARBONIZED RICE STALK BRIQUETTES

2020 ◽  
pp. 221-229
Author(s):  
Rapheal Ige ◽  
Elinge Ogala ◽  
Cosmos Moki ◽  
Abdulrahman Habeeb
Keyword(s):  
Moisture Content ◽  
Carbon Content ◽  
Calorific Value ◽  
Volatile Matter ◽  
Ash Content ◽  
Hot Water ◽  
High Concentration ◽  
Fixed Carbon ◽  
Binder Ratio ◽  
Fixed Carbon Content

The selection or choice of agro-waste briquettes for domestic and industrial cottage applications depends on the fuel properties. In this study, the briquette was produced by carbonizing the rice stalk followed by crushing and sieving, the binder was prepared by dissolving the starch in hot water, then mixed with the sieved carbonized rice stalk and then the briquette was produced using the briquetting machine. Proximate analyses, viability, characteristics and combustion were determined to know the average composition of their constituents. From the results obtained it was observed that ash content, moisture content, after glow and ignition propagation decrease as the binder ratio increase while fixed carbon content, volatile matter, calorific value, density and compressive strength increase. The results of this work indicate that briquettes produced using high concentration of the binder would make good biomass fuels. However, it has a high moisture content of 25.00%, high ash content of 23.00%, moderate volatile matter of 44.80%, low fixed carbon content of 32.20%, moderate calorific value of 13.86 MJ/Kg and high density of 0.643g/cm3. The results obtained for all the parameters showed that rice stalks briquettes produced with high concentration of the binder (starch) had a better performance based on their combustion profile.

Utilization of Tetrapleura tetraptera Waste for Energy and Climate Change Mitigation

2018 ◽  
Vol 1 (1) ◽  
pp. 8-12 ◽  
Author(s):  
N.S.A. Derkyi ◽  
N.S.A. Derkyi
Keyword(s):  
Climate Change ◽  
Carbon Content ◽  
Wood Species ◽  
Climate Change Mitigation ◽  
Alcoholic Beverage ◽  
Charcoal Production ◽  
Fixed Carbon ◽  
Tetrapleura Tetraptera ◽  
Fixed Carbon Content ◽  
Change Mitigation

Charcoal production as practiced in Ghana contributes greatly to the deterioration of the environment through deforestation.Tetrapleura tetraptera is used as a spice and thickener as well as syrup and condiments among others. It now finds wideusage in the alcoholic and non-alcoholic beverage industries. In these operations, huge quantities of waste are generated.The objective of this work was to convert the waste into energy for climate change mitigation. The woody fruit residue ofT. tetraptera and wood cut from the forest were carbonized into charcoal in a steel carbonizer at a temperature of 5000C.Charcoal yield, physicochemical and energy properties were determined. The quantity of trees that would have been cut fromthe forest to produce the same amount of charcoal as obtained from the woody fruit residue was determined. The charcoalyield from Cylicodiscus gabonensis and Acacia nilotica was 25% each whilst the yield from T. tetraptera woody fruit residuewas 30%. T. tetraptera fruit residue was found to be a high yielding charcoal. It showed quality charcoal in terms of highcalorific value and fixed carbon content comparing with the preferred wood species investigated. The use of T. tetraptera fruitwaste is therefore a suitable sustainable option for charcoal production and this option will greatly reduce the environmentalpollution caused by the indiscriminate dumping of the waste.

Improvement of Combustion Quality of Biomass Briquette from Water Hyacinth (Eichhornia crassipes) for Alternative Energy

2019 ◽  
Vol 2 (1) ◽  
pp. 1-7
Author(s):  
Andre Nugraha Pramadhana ◽  
Diah Indriani Widiputri ◽  
Gustan Pari
Keyword(s):  
Carbon Content ◽  
Water Hyacinth ◽  
Alternative Energy ◽  
Eichhornia Crassipes ◽  
Aquatic Vegetation ◽  
Calorific Value ◽  
Combustion Characteristic ◽  
Fixed Carbon ◽  
Promising Alternative ◽  
Fixed Carbon Content

Water hyacinth (Eichhornia crassipes) is a floating plant species, which spreads rapidly in fresh water area. This plant has found to cause environmental problems, such as clogging drainage, water intakes, and ditches, shading out other aquatic vegetation and interfering with fishing, shipping as well as recreational activities. In contrast to its drawbacks, water hyacinth is considered as one of the potential agricultural wastes in Indonesia that can be processed into an alternative solid fuel. Carbonization followed by briquetting is one of the methods that can be applied to process biomass into solid fuels. This work investigated the effect of carbonization temperature and two different types of binders on combustion characteristic of water hyacinth biomass. In this work, carbonization was carried out at three different temperatures, i.e. 350oC, 400oC and 450oC, while comparing the application of two types of binders, which were tapioca gel and polyvinyl acetate (PVAc) adhesive. The results showed that carbonization process of water hyacinth increased the fixed carbon content and the calorific value, and the best result was obtained at 450oC with tapioca gel as the binder. With this condition, the fixed carbon content in the biomass briquette could be increased up to 34.14% with a calorific value of 3,837 kcal/kg. Although the combustion efficiency was only 4.89%. The application of water hyacinth as biomass briquette has shown a promising alternative to reduce CO emission and the above-mentioned environment problems.

Thermogravimetric Analysis of Plastic and Biomass under Different Oxygen Concentration

2013 ◽  
Vol 864-867 ◽  
pp. 1985-1988
Author(s):  
Jun Zhao ◽  
Shu Zhong Wang ◽  
Zhi Qiang Wu ◽  
Lin Chen ◽  
Hai Yu Meng
Keyword(s):  
Thermogravimetric Analysis ◽  
Carbon Content ◽  
Oxygen Concentration ◽  
Ignition Temperature ◽  
Reaction Rate ◽  
Biomass Pyrolysis ◽  
Fixed Carbon ◽  
Pyrolysis Reaction ◽  
Fixed Carbon Content ◽  
Ignition Characteristics

This paper simulates the plastic and biomass pyrolysis and ignition characteristics in different atmosphere, by thermogravimetric analysis polypropylene and plane wood at different oxygen concentrations. Experiments show that, increase the concentration of oxygen can accelerate the pyrolysis reaction rate of biomass and plastics, and can also reduce the ignition temperature of them. But for high volatile substances, such as plastic, the increase of oxygen concentration make a smaller effect on the pyrolysis and ignition, and for relatively high fixed carbon content substances, such as plane woods, the increase of oxygen concentration make a larger effect on pyrolysis and ignition.

scholarly journals Quantitative Inversion of Fixed Carbon Content in Coal Gangue by Thermal Infrared Spectral Data

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1659 ◽  
Author(s):  
Liang Song ◽  
Shanjun Liu ◽  
Wenwen Li
Keyword(s):  
Infrared Spectrum ◽  
Carbon Content ◽  
Spectral Index ◽  
Spectral Characteristics ◽  
Thermal Infrared ◽  
Coal Gangue ◽  
Mine Safety ◽  
Support Vector ◽  
Fixed Carbon ◽  
Fixed Carbon Content

Fixed carbon content is an important factor in measuring the carbon content of gangue, which is important for monitoring the spontaneous combustion of gangue and reusing coal gangue resources. Although traditional measurement methods of fixed carbon content, such as chemical tests, can achieve high accuracy, meeting the actual needs of mines via these tests is difficult because the measurement process is time consuming and costly and requires professional input. In this paper, we obtained the thermal infrared spectrum of coal gangue and developed a new spectral index to achieve the automated quantification of fixed carbon content. Thermal infrared spectroscopy analyses of 42 gangue and three coal samples were performed using a Turbo FT thermal infrared spectrometer. Then, the ratio index (RI), difference index (DI) and normalized difference index (NDI) were defined based on the spectral characteristics. The correlation coefficient between the spectral index and the thermal infrared spectrum was calculated, and a regression model was established by selecting the optimal spectral DI. The model prediction results were verified by a ten times 5-fold cross-validation method. The results showed that the mean error of the proposed method is 5.00%, and the root mean square error is 6.70. For comparison, the fixed carbon content was further predicted by another four methods, according to the spectral depth H, spectral area A, the random forest and support vector machine algorithms. The predicted accuracy calculated by the proposed method was the best among the five methods. Therefore, this model can be applied to predict the fixed carbon content of coal gangue in coal mines and can help guide mine safety and environmental protection, and it presents the advantages of being economic, rapid and efficient.

scholarly journals Alternative Fuels from Forestry Biomass Residue: Torrefaction Process of Horse Chestnuts, Oak Acorns, and Spruce Cones

Energies ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2468 ◽  
Author(s):  
Arkadiusz Dyjakon ◽  
Tomasz Noszczyk
Keyword(s):  
Carbon Content ◽  
Alternative Fuels ◽  
Combustion Process ◽  
Energy System ◽  
Hard Coal ◽  
Energy Yield ◽  
Fixed Carbon ◽  
Heating Value ◽  
Wide Range ◽  
Fixed Carbon Content

The global energy system needs new, environmentally friendly, alternative fuels. Biomass is a good source of energy with global potential. Forestry biomass (especially wood, bark, or trees fruit) can be used in the energy process. However, the direct use of raw biomass in the combustion process (heating or electricity generation) is not recommended due to its unstable and low energetic properties. Raw biomass is characterized by high moisture content, low heating value, and hydrophilic propensities. The initial thermal processing and valorization of biomass improves its properties. One of these processes is torrefaction. In this study, forestry biomass residues such as horse chestnuts, oak acorns, and spruce cones were investigated. The torrefaction process was carried out in temperatures ranging from 200 °C to 320 °C in a non-oxidative atmosphere. The raw and torrefied materials were subjected to a wide range of tests including proximate analysis, fixed carbon content, hydrophobicity, density, and energy yield. The analyses indicated that the torrefaction process improves the fuel properties of horse chestnuts, oak acorns, and spruce cones. The properties of torrefied biomass at 320 °C were very similar to hard coal. In the case of horse chestnuts, an increase in fixed carbon content from 18.1% to 44.7%, and a decrease in volatiles from 82.9% to 59.8% were determined. Additionally, torrefied materials were characterized by their hydrophobic properties. In terms of energy yield, the highest value was achieved for oak acorns torrefied at 280 °C and amounted to 1.25. Moreover, higher heating value for the investigated forestry fruit residues ranged from 24.5 MJ·kg−1 to almost 27.0 MJ·kg−1 (at a torrefaction temperature of 320 °C).

Sign in / Sign up

Export Citation Format

Share Document