fixed carbon
Recently Published Documents


TOTAL DOCUMENTS

429
(FIVE YEARS 166)

H-INDEX

37
(FIVE YEARS 4)

2022 ◽  
Vol 2022 ◽  
pp. 1-13
Author(s):  
Assefa Tesfaye ◽  
Fentahun Workie ◽  
Venkatesh S. Kumar

Biomass energy accounts for more than 92 percent of overall energy consumption in Ethiopia. As a result, Ethiopia is one of the world’s most biomass-dependent countries. The high reliance on wood fuels and agricultural residues for fuel harms society’s social, economic, and environmental well-being. This study aims to create and test the quality of fuel briquettes made from the coffee husk. Also built and produced are a carboniser/charcoal kiln, a manually operated molder system, and a briquette stove for burning the manufactured briquette. The carboniser converts 15 kg of raw coffee husk into 6 kg of carbonised char in 25 minutes, and the manually operated briquette molder can press 30 kg per hour. The efficiency of converting raw coffee husk into carbonised char content was 40.12%. In the geological survey of Ethiopia, the geochemical laboratory directorate received triplicate samples of the fuel briquette charcoal for analysis. Moisture content, fixed carbon content, ash content, sulfur content, and calorific value were determined using a bomb calorimeter and a ceramic lining furnace. Physical properties of fuel briquettes ranged from 10.03% moisture content, 970 kg/m3 density, 81% fixed carbon, 5.15% ash content, 0% sulfur, and 30.54 Kcal/kg higher heating value, according to laboratory results. The results of the study revealed that the coffee husk fuel briquettes produced have more positive characteristics. Fuel briquettes were cost-effective and environmentally friendly and reduced deforestation compared to firewood. This study clearly shows that briquettes made from coffee husk could be used as an alternative energy source when this kind of waste is well managed.


2022 ◽  
Author(s):  
Cindy E. Prescott

Abstract Plants engage in many processes and relationships that appear to be wasteful of the high-energy compounds that they produce through carbon fixation and photosynthesis. For example, living trees keep leafless tree stumps alive (i.e. respiring) and support shaded understory trees by sharing carbohydrates through root grafts or mycorrhizal fungal networks. Plants exude a variety of organic compounds from their roots and leaves, which support abundant rhizosphere and phyllosphere microbiomes. Some plants release substantial amounts of sugar via extra-floral nectaries, which enrich throughfall and alter lichen communities beneath the canopy. Large amounts of photosynthetically fixed carbon are transferred to root associates such as mycorrhizal fungi and N-fixing micro-organisms. In roots, some fixed C is respired through an alternative non-phosphorylating pathway that oxidizes excess sugar. Each of these processes is most prevalent when plants are growing under mild-to-moderate deficiencies or nutrients or water, or under high light or elevated atmospheric CO2. Under these conditions, plants produce more fixed carbon than they can use for primary metabolism and growth, and so have ‘surplus carbon’. To prevent cellular damage, these compounds must be transformed into other compounds or removed from the leaf. Each of the above phenomena represents a potential sink for these surplus carbohydrates. The fundamental ‘purpose’ of these phenomena may therefore be to alleviate the plant of surplus fixed C.


2022 ◽  
Author(s):  
Fabíola Martins Delatorre ◽  
Gabriela Fontes Mayrinck Cupertino ◽  
Michel Picanço Oliveira ◽  
Felipe Silva Gomes ◽  
Luciene Paula Roberto Profeti ◽  
...  

Abstract This study aims to evaluate charcoal fines as potential reinforcing agents in biocomposites. Charcoal has both high carbon content and surface area depending on the manufacturing temperatures. Charcoal is a common residue in the coal industry that we propose using it to reinforce filling agents in several matrices in order to add value to this residue. This study investigated charcoal fines when using three pyrolysis temperatures (400, 600, and 800°C) to identify the most suitable charcoal to be used as raw materials in producing carbon biocomposites. We evaluated apparent density, porosity, morphology, and immediate chemical composition, and then performed a Fourier-transform infrared spectroscopy (FTIR) and an X-ray photoelectron spectroscopy (XPS). Charcoal fines produced at 800°C showed promising results as a polymeric matrix filling due to their higher porosity (81.08%), fixed carbon content (96.77%), and hydrophobicity.


2021 ◽  
Vol 25 (9) ◽  
pp. 1707-1713
Author(s):  
O.O.E. Onawumi ◽  
A.A. Sangoremi ◽  
O.S. Bello

This study was carried out to prepare groundnut shell (GS) and eggshell (ES) into activated carbon (AC) and characterize the AC using Association of Official Analytical Chemists (AOAC) and American Standard for Testing and Materials (ASTM) methods. The AC produced was characterized for: pH, moisture content, volatile matter, ash content, fixed carbon, bulk density and surface area. Surface functional groups and surface morphology were also determined using Fourier Transformed Infrared (FT-IR) and Scanning Electron Microscope (SEM) respectively. The ranges of the following results were achieved for the biomasses: Groundnut shell Activated Carbon (GSAC) and Eggshell Activated Carbon (ESAC) respectively: pH (6.80±0.101−7.80±0.011); moisture content (14.10±0.101−12.90±.110%); volatile matter (9.20±0.112−9.90±0.012%); ash content (8.98±0.111−5.80±0.111%); fixed carbon (67.70±0.010−71.40±110%); bulk density (370.00±0.000−380.00−0.000 g/L); surface area (880.00±0.100−800.00±0.000 m2/g). The agro-wastes have high carbon contents and low inorganic which make them viable adsorbents. FT-IR analysis revealed the presence of oxygen surface complexes such as carbonyls and OH groups on the surface of the ACs in addition to good pore structures from SEM studies revealed that the agro-wastes could be good precursors for ACs production. The overall results showed that the AC produced from the agro-wastes can be optimally used as good and effective adsorbents, thereby ensuring cheaper, readily available and affordable ACs for the treatment of effluent, waste water and used oils.


2021 ◽  
Vol 13 (24) ◽  
pp. 13796
Author(s):  
Aisha Nazir ◽  
Um-e- Laila ◽  
Firdaus-e- Bareen ◽  
Erum Hameed ◽  
Muhammad Shafiq

The current research encompasses utilization of peanut shells (PS) as feedstock for pyrolysis carried out at various temperatures (250, 400, and 550 °C) for deriving biochar, namely PS-BC250, PS-BC400, and PS-BC550. After analyzing the biochar types physicochemically, it was applied as a soil ameliorant for the growth of cucumber. The results showed that in prepared biochar type, bulk density, volatile contents, hydrogen, oxygen, and nitrogen content decreased, whereas pH, electrical conductivity, ash content, fixed carbon content, and surface area increased with the increasing temperature. Scanning electron microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) presented high porosity, re-orientation of vessels, and a greater number of aromatic compounds, respectively, for PS-BC prepared at 550 °C. On applying PS-BC250, PS-BC400, and PS-BC550 as amendments in potted soil at 2, 4, and 6% (w/w), it improved soil quality (viz pH, ECe, BD, and soil water holding capacity) and increased the yield of cucumber. Because of improved soil properties and crop yield, PS-BC550 at the rate of 4% (w/w) demonstrated a great potential for agricultural application while provisioning dual circular economic indicators in the form of diverting PS waste to an effective alternative of chemical fertilizer having intensive carbon footprints in cucumber production.


Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2406
Author(s):  
Nick Gould ◽  
Michael R. Thorpe ◽  
Joe T. Taylor ◽  
Helen L. Boldingh ◽  
Catherine M. McKenzie ◽  
...  

This work aims to understand how Vitis vinifera (Chardonnay) vines prioritise the export and distribution of recently fixed photoassimilate between root tissue, fruit, and defence, following the elicitation of a defence response. Jasmonic acid (JA) and its methyl ester, MeJA, are endogenous plant hormones, known collectively as jasmonates, that have signalling roles in plant defence and consequently are often used to prime plant defence systems. Here, we use exogenous jasmonate application to mature source leaves of Chardonnay grapevines to elucidate the prioritisation strategy of carbon allocation between plant defence and growth. Our results demonstrate that jasmonate application to Chardonnay leaves can elicit a defence response to Botrytis cinerea, but the effect was localised to the jasmonate-treated area. We found no evidence of a systemic defence response in non-treated mature leaves or young growing tissue. JA application reduced the photosynthetic rate of the treated leaf and reduced the export rate of recently fixed carbon-11 from the leaf. Following JA application, a greater proportion of available recently fixed carbon was allocated to the roots, suggesting an increase in sink strength of the roots. Relative sink strength of the berries did not change; however, an increase in berry sugar was observed seven days after JA treatment. We conclude that the data provide evidence for a “high sugar resistance” model in the mature treated leaves of the vine, since the export of carbon was reduced to ensure an elevated defence response in the treated leaf. The increase in berry sugar concentration seven days after treatment can be explained by the initial prioritisation of a greater portion of the exported carbon to storage in the roots, making it available for remobilisation to the berries once the challenge to defence had passed.


2021 ◽  
Author(s):  
◽  
Tiffany Bock

<p>Anthopleura aureoradiata, a common sea anemone of New Zealand's intertidal mudflats and rocky shores, hosts symbiotic dinoflagellates of the genus Symbiodinium. This study investigated the control of photosynthetic carbon translocation in this symbiosis, and in particular the presence and operation of socalled 'host release factor' (HRF). Evidence for HRF exists in a number other algalinvertebrate symbioses, where tissue extracts of the host stimulate carbon release by isolated algal symbionts. However, its identity remains elusive and it has never been studied before in A. aureoradiata. Translocation of photosynthetically-fixed carbon in the intact symbiosis and in the presence of host tissue extract was measured using a 14C label. Zooxanthellae in the intact symbiosis released around 40% of their photosynthetically-fixed carbon to the anemone. Isolated zooxanthellae, however, translocated only 8%, even less than the amount of photosynthate liberated by zooxanthellae in FSW alone (11%). Photosynthetic rates per algal cell were similar in the intact symbiosis and both host homogenate and FSW incubations, meaning that the total amount of photosynthetically-fixed carbon released (in pg C/cell/h) by the zooxanthellae in these different situations reflected the %translocation values. Given the failure of homologous zooxanthellae (i.e. those from A. aureoradiata) to respond to homogenized host tissue, it was tested whether zooxanthellae from other host species (i.e. cultured heterologous algae) responded. Heterologous zooxanthellae representing 5 clades (A-E) of Symbiodinium were incubated in host tissue homogenate and photosynthate release again measured with 14C. The %translocation varied from 12-51% in A. aureoradiata homogenate and 17-67% in FSW, again suggesting a lack of an active HRF in the homogenized tissues of this sea anemone. Photosynthetic rates amongst the different heterologous algae also varied widely with, for instance, freshly isolated zooxanthellae from A. aureoradiata having 6-fold higher photosynthetic rates than cultured algae from the same clade (clade A). The zooxanthellae of A. aureoradiata are known to be N-sufficient in the field, and studies with other species have demonstrated that N-deficient zooxanthellae release more photosynthate in response to HRF than do N-sufficient ones. Therefore, induction of an HRF effect was attempted by starving sea anemones, and hence their zooxanthellae, prior to incubation of freshly isolated zooxanthellae in homogenized tissue. However, even after 8 weeks of starvation, the zooxanthellae showed no signs of N-deficiency (as indicated by the extent to which ammonium enhanced the rate of dark 14C fixation), meaning that the relationship with HRF activity could not be examined. The ability of these temperate zooxanthellae to maintain their Nsufficiency, even after relatively long periods of food deprivation, may indicate a lower reliance on host feeding for nitrogen than is seen in tropical zooxanthellae, or a greater capacity to use internal stores of nitrogen. The lack of photosynthate release by both homologous and heterologous zooxanthellae in host homogenate, as opposed to substantial carbon released in the intact symbiosis, suggests that control of carbon translocation in A. aureoradiata is not related to the activity of an HRF; alternatively, if an HRF is present, its activity is hindered when the symbiosis is disrupted. Further study is needed to determine what is responsible for the control of photosynthate translocation in the A. aureoradiata-Symbiodinium symbiosis.</p>


2021 ◽  
Author(s):  
◽  
Tiffany Bock

<p>Anthopleura aureoradiata, a common sea anemone of New Zealand's intertidal mudflats and rocky shores, hosts symbiotic dinoflagellates of the genus Symbiodinium. This study investigated the control of photosynthetic carbon translocation in this symbiosis, and in particular the presence and operation of socalled 'host release factor' (HRF). Evidence for HRF exists in a number other algalinvertebrate symbioses, where tissue extracts of the host stimulate carbon release by isolated algal symbionts. However, its identity remains elusive and it has never been studied before in A. aureoradiata. Translocation of photosynthetically-fixed carbon in the intact symbiosis and in the presence of host tissue extract was measured using a 14C label. Zooxanthellae in the intact symbiosis released around 40% of their photosynthetically-fixed carbon to the anemone. Isolated zooxanthellae, however, translocated only 8%, even less than the amount of photosynthate liberated by zooxanthellae in FSW alone (11%). Photosynthetic rates per algal cell were similar in the intact symbiosis and both host homogenate and FSW incubations, meaning that the total amount of photosynthetically-fixed carbon released (in pg C/cell/h) by the zooxanthellae in these different situations reflected the %translocation values. Given the failure of homologous zooxanthellae (i.e. those from A. aureoradiata) to respond to homogenized host tissue, it was tested whether zooxanthellae from other host species (i.e. cultured heterologous algae) responded. Heterologous zooxanthellae representing 5 clades (A-E) of Symbiodinium were incubated in host tissue homogenate and photosynthate release again measured with 14C. The %translocation varied from 12-51% in A. aureoradiata homogenate and 17-67% in FSW, again suggesting a lack of an active HRF in the homogenized tissues of this sea anemone. Photosynthetic rates amongst the different heterologous algae also varied widely with, for instance, freshly isolated zooxanthellae from A. aureoradiata having 6-fold higher photosynthetic rates than cultured algae from the same clade (clade A). The zooxanthellae of A. aureoradiata are known to be N-sufficient in the field, and studies with other species have demonstrated that N-deficient zooxanthellae release more photosynthate in response to HRF than do N-sufficient ones. Therefore, induction of an HRF effect was attempted by starving sea anemones, and hence their zooxanthellae, prior to incubation of freshly isolated zooxanthellae in homogenized tissue. However, even after 8 weeks of starvation, the zooxanthellae showed no signs of N-deficiency (as indicated by the extent to which ammonium enhanced the rate of dark 14C fixation), meaning that the relationship with HRF activity could not be examined. The ability of these temperate zooxanthellae to maintain their Nsufficiency, even after relatively long periods of food deprivation, may indicate a lower reliance on host feeding for nitrogen than is seen in tropical zooxanthellae, or a greater capacity to use internal stores of nitrogen. The lack of photosynthate release by both homologous and heterologous zooxanthellae in host homogenate, as opposed to substantial carbon released in the intact symbiosis, suggests that control of carbon translocation in A. aureoradiata is not related to the activity of an HRF; alternatively, if an HRF is present, its activity is hindered when the symbiosis is disrupted. Further study is needed to determine what is responsible for the control of photosynthate translocation in the A. aureoradiata-Symbiodinium symbiosis.</p>


2021 ◽  
Vol 4 (3) ◽  
pp. 391-402
Author(s):  
Irvan Adhin Cholilie ◽  
Larinda Zuari
Keyword(s):  

Bahan utama biobriket dan jenis bahan perekat sangat menentukan kualitas biobriket. Penelitian ini bertujuan untuk mengetahui pengaruh  jenis perekat terhadap kualitas biobriket. Bahan yang digunakan untuk membuat biobriket yaitu serabut dan tandan buah lontar, dengan jenis perekat tepung tapioka, tepung sagu dan tepung maizena. Dilakukan analisis pada biobriket yang menggunakan tiga jenis perekat tersebut. Penelitian ini menggunakan beberapa     pengujian, diantaranya nilai kalor, kadar air, kadar abu, volatile matter, fixed carbon dan laju pembakaran. Penelitian menggunakan metode rancangan acak lengkap, dengan 3 perlakuan dan 3 ulangan. Tepung tapioka menghasilkan kadar air tertinggi 6.6 % dan kadar zat terbang terendah 22.17 %, tepung sagu memiliki kadar abu dan nilai kalor tertinggi yaitu 29.33 % dan 5015.98 kal/gram. Tepung maizena mempunyai kadar air dan kadar abu terendah yaitu 3.5 % dan 27.33 %. Tepung maizena mempunyai kadar zat terbang dan kadar karbon tertinggi yaitu 24,99% dan 44,18%, serta tepung maizena mempunyai nyala api lebih mudah menyala selama 292 detik serta memiliki waktu paling lama yaitu 0,147 gram/menit.


2021 ◽  
Vol 882 (1) ◽  
pp. 012029
Author(s):  
M A Rahmanta

Abstract The Coal Water Slurry (CWS) technology increases the calorific value and changes the phase of coal from solid to liquid. The CWS Plant with a coal capacity of 1.4 t/hour located at Karawang, West Java converts lignite coal to CWS. Coal undergoes pulverizing, upgrading, and slurry-making processes to become CWS. Pulverization is the process of refining coal size into 200 mesh. The upgrading process is through reducing the moisture content in heat exchangers (HE). It occurs in HE where the coal is pressurized to 15 MPa and the temperature is maintained at 330 0C for 30 minutes. The research objective was to determine the CWS characteristics of the South Sumatra Pendopo lignite coal. The method used is through testing where the Pendopo coal is converted into CWS at the CWS Plant. The result shows that Pendopo coal which has a heating value of High Heating Value (HHV) 2,725.00 kCal/kg As Received (AR) has an increase in HHV heating value of 3,218.00 kcal/kg AR when it becomes CWS. The total moisture content of Pendopo coal has decreased from 49.36% to 44.58% when it becomes CWS. The fixed carbon content of Pendopo coal increased from 19.78% AR to 24.01% AR.


Sign in / Sign up

Export Citation Format

Share Document