scholarly journals Quality Properties and Pyrolysis Characteristics of Cassava Rhizome Pellets Produced by Alternating between Pelletizing and Torrefaction

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 930
Author(s):  
Nitipong Soponpongpipat ◽  
Paisan Comsawang ◽  
Suwat Nanetoe

This work investigated quality properties of pellets of raw cassava rhizome (P-RC), pellets of pelletized cassava rhizome followed by torrefaction (T-CP), and pellets of torrefied cassava rhizome followed by pelletizing (P-TC). Torrefaction was conducted at temperatures of 230, 250, and 280 °C for 30 min. Pyrolysis characteristics of T-CP and P-TC at torrefied temperatures of 230 and 250 °C were studied using thermogravimetric analysis. It was found that at the similar torrefied temperature, P-TC had a higher bulk density, energy density, and pellet durability than that of T-CP and P-RC while T-CP had a higher HHV and moisture absorption than P-TC and P-RC. The bulk density of P-TC was 1.13–1.19 and 1.33–1.52 times higher than that of P-RC and T-CP, respectively. The HHV of T-CP was 1.07 and 1.29 times higher than P-TC and P-RC, respectively. The energy density of P-TC was 1.24–1.56 and 1.20–1.41 times higher than that of P-RC and T-CP. In terms of Pellet Fuel Institute (PFI) standard, the durability index of P-RC, P-TC, and T-CP at torrefied temperatures of 230 and 250 °C was acceptable. However, dramatically low and unacceptable durability index was found in case of T-CP at torrefied temperature of 280 °C. The moisture absorption of P-TC was lower than that of P-RC and T-CP. Finally, T-CP had a lower pyrolysis temperature and had a much lower solid yield than that of P-TC. Variation of pyrolysis characteristics indicated the difference in chemical composition between T-CP and P-TC.

2013 ◽  
Vol 805-806 ◽  
pp. 265-268 ◽  
Author(s):  
Fang Ming Cui ◽  
Xiao Yuan Zhang ◽  
Li Min Shang

Thermogravimetric analysis (TGA) was employed to study the pyrolysis characteristics of four glucose-based and three fructose-based carbohydrates. Kinetic parameters were calculated based on the experiment data. The results indicated that the starting and maximal pyrolysis temperatures of the glucose-based carbohydrates were increased steadily as the rising of their degree of polymerization (DP). The fructose-based carbohydrates exhibited similar pyrolysis behaviors as the glucose-based carbohydrates, but the difference was smaller. Kinetic calculations revealed that the activation energy values of the glucose-based carbohydrates were higher than those of the fructose-based carbohydrates, indicating the glucose-based carbohydrates were more difficult to decompose than the fructose-based carbohydrates.


2015 ◽  
Vol 659 ◽  
pp. 74-79 ◽  
Author(s):  
Sutas Janbuala ◽  
Thanakorn Wasanapiarnpong

The objective of this study is to investigate the effect of rice husk and rice husk ash which have the difference chemical composition and organic matter on porosity and properties of lightweight clay brick . Comparative adding between rice husk and rice husk ash were varied by 10, 20, 30, 40 % by weight. The results showed that more adding of rice husk and rice husk ash increase pore in microstructure and water absorption, while decrease bulk density. Porosity and water absorption are maximized when the rice husk are added at 40 %. The clay brick with 10, 20 and 30 % of rice husk or rice husk ash addition showed the required density and compressive strength followed the industrial standard of lightweight brick. The addition with 10 % of rice husk showed the best properties as 1.20 g/cm3 of bulk density and 4.6 MPa of compressive strength with 36.57 % of porosity. Whereas, the 10 % addition of rice husk ash showed 1.18 g/cm3 of bulk density and 5.97 MPa with 37.27 % of porosity.


2020 ◽  
Vol 34 (22n24) ◽  
pp. 2040130
Author(s):  
Se-Yoon Kim ◽  
Soo-Jeong Park ◽  
Chang-Wook Park ◽  
Yun-Hae Kim

Slag fiber has economic and environmental advantages in that it converts a low-value-added material to a high-value-added material. However, although the slag fiber has a chemical composition similar to basalt fiber, its competitiveness in the fiber industry is significantly lower. Moreover, the slag fiber remains in the pre-commercial stage due to the uncertainty and instability of the basic properties. Therefore, in this study, the slag fiber customized through the fiberization process was compared with the existing basalt fiber to analyze the effect of the similarity of chemical composition on the environmental degradation characteristics and mechanical properties under tensile loading. As a result, the slag filament composites showed lower tensile strength due to the weaker interfacial bonding strength with the epoxy matrix than the basalt filament composites, but the difference in decreased tensile strength rate was not significant. In addition, long-term moisture absorption in fresh water and seawater demonstrated excellent moisture absorption resistance.


1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.


Geophysics ◽  
1983 ◽  
Vol 48 (3) ◽  
pp. 341-356 ◽  
Author(s):  
T. R. LaFehr

The borehole gravity meter (BHGM) is recognized as an important logging tool for obtaining formation bulk density. In general, however, the difference between two gravity observations vertically separated in a well leads to an apparent and not the actual bulk density. BHGM‐derived apparent densities are equal to the formation bulk densities when the instrument passes through beds which are horizontal, infinitely extended laterally, uniformly thick, and constant in density. For many applications, departures from these assumed conditions are so slight that their effects can be ignored, and the BHGM essentially yields bulk density with a large radius of investigation. In the presence of anomalous masses, significant distortion in formation bulk density is possible. The apparent density anomaly produced in the well by an elongated, offset density contrast is proportional to the angle subtended by the density‐change interface. For a density‐change boundary having circular symmetry with respect to the well, the apparent density anomaly at the center of the bed is proportional to the sine of the subtended angle. Because the distortion in bulk density is the same above a horizontal boundary as it is just below (in the limit, at the boundary, for a normally incident well), an abrupt change in apparent density is equal to the real density change at the boundary. This change in density, termed “the Poisson jump,” is independent of geometry; our ability to measure it, however, is a function of station location with respect to the geologic bodies. Two methods are suggested for obtaining bulk densities from BHGM apparent densities: (1) by obtaining two stations just outside as well as just within the zone of interest, the Poisson jump can be approximated and added to an independent density source (e.g., the gamma‐gamma log), and (2) the apparent density anomaly within the formation of interest can be derived by modeling (perhaps based on seismic or well data) and added to the BHGM‐determined densities. Thinner beds can be studied with the BHGM than generally believed, even with much greater station spacing.


2014 ◽  
Vol 1008-1009 ◽  
pp. 247-251
Author(s):  
Wipawan Sangsanga ◽  
Chuan Na ◽  
Jin Xiao Dou ◽  
Jiang Long Yu

The catalytic effects of Zn on the release of the gaseous products during pyrolysis of Shenhua lignite was investigated by using a fixed-bed quartz reactor. The product gas compositions from the coal pyrolysis were analyzed by a gas chromatography (GC). Experimental results show that Zn had noticeable catalytic effects on lignite pyrolysis. With the increase in Zn content, lignite weight loss increases during pyrolysis. However, there was an optimum content for amount Zn into the coal. Pyrolysis temperature had a great impact on the composition of pyrolysis gas. As the pyrolysis temperature increased, char yield decreased and gas yield increased. There existed a temperature that tar yield reached its maximum value.


Author(s):  
John K. Keogh ◽  
Brendan F. Keegan

Morphological study of the podia of the suspension feeding Amphiura filiformis and the deposit feeding Amphiura chiajei revealed sensory–secretory complexes in the podial epidermis, consisting of four cells, two secretory and two sensory. Large mucus cells were found in association, but not exclusively, with the sensory–secretory complexes. In A. filiformis, mucus cells stained positively for both acid and neutral mucopolysaccharides, while, in A. chiajei, these cells stained only for acid mucopolysaccharides. The surfaces of the arm podia in A. chiajei were relatively smooth, while the arm podia of A. filiformis bear papillae. The sensory–secretory complexes open through numerous paired pores, with each pair having an intervening cilium. Pores were restricted to the podial tip in A. chiajei, while in A. filiformis they are concentrated on the podial tip and on the papillae. Amphiura chiajei shows very little differentiation of the podia along the length of the arm. In A. filiformis, the distal podia have papillae throughout their entire length, with pores being found on the head region and the papillar tips. Here, the papillae are oriented in such a way (i.e. facing inward towards the ventral arm plate) as to increase the area of the filtering surface of the podium, serviced by the sticky secretions from the sensory–secretory complexes. The proximal podia are relatively simple in structure and are thought to function more in the transportation of mucus wrapped particles to the mouth rather than in their capture. The difference in structure of the podia and chemical composition of podial secretory cells are taken to reflect the difference in feeding styles of the two species.


2014 ◽  
Vol 3 (6) ◽  
pp. 107 ◽  
Author(s):  
Sushil K. Singh ◽  
K. Muthukumarappan

<p>Nutritionally balanced ingredient blends for catla (<em>Catla catla</em>), belonging to the family Cyprinidae, were extruded using single screw extruder. The extrusion was carried out at five levels of soy white flakes content (21%, 29%, 40%, 52%, and 59% db), five levels of moisture content (15, 19, 25, 31, and 35% db) and five levels of barrel temperature (100, 110, 125, 140, and 150 ºC) using three different die nozzles (having L/D ratios 3.33, 5.83, and 7.25). Blends with net protein content of 32.5% contains soy white flakes, along with high protein distillers dried grains (HP-DDG), corn flour, corn gluten meal, fish meal, vitamin, and mineral mix. A central composite rotatable design (CCRD) and  response surface methodology (RSM) was used to investigate the significance of independent and interaction effects of the extrusion process variables on the extrudates physical properties namely pellet durability index, bulk density, water absorption and solubility indices and expansion ratio. Quadratic polynomial regression equations were developed to correlate the product responses and process variables as well as to obtain the response surfaces plots. The independent variables had significant (<em>P </em>&lt; 0.05) effects on physical properties of extrudates: (i) higher soy white flakes content increased the pellet durability index and water absorption index, but decreased the water solubility index, (ii) higher temperature decreased pellet durability index, bulk density and water solubility index, (iii) increased L/D ratio from 3.33 to 7.25 increased the pellet durability index, expansion ratio but decreased the bulk density of the extrudates.</p>


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