Effect of Valley Beater Refining on Tensile Properties of Molded Pulps from Rice Straws

2021 ◽  
Vol 889 ◽  
pp. 73-78
Author(s):  
Ruethaichanok Prasertpong ◽  
Phattharasaya Rattanawongkun ◽  
Nattaya Tawichai ◽  
Uraiwan Intatha ◽  
Nattakan Soykeabkaew

Rice straw, an abundant agricultural waste, is shown to be a promising resource for pulp and paper packaging manufacturing. In this study, rice straw pulps or cellulose fibers were extracted using a soda-AQ process and then the rice straw pulp slurries were refined by a Valley beater. The effect of refining time (15-60 min) on the pulp fiber characteristics was studied. It was found that both initial fiber length and width were decreased with refining time. The refined fibers became fibrillated, finer, and also more uniform in size confirmed by SEM. The pulp freeness (CSF) was reduced with increasing refining time as expected due to higher water-holding capacity of more fibrillated pulps. Then, the molded sheets were formed from the prepared rice straw pulps and examined. From tensile testing, the results indicated that the tensile properties of the molded sheets from the refined pulps were significantly enhanced (p < 0.05), thanks to an increase in fibrillated fiber surface area and inter-fiber bonding degree. The Valley beater refined rice straw pulp provided the molded sheet with the highest tensile index of 51.96 ± 4.08 Nm/g which are comparable to that of the sheets prepared from PFI mill refining process. The tensile properties of the current refined sheets were also in the acceptable range for typical commercial molded pulp packaging. In addition, the freeness values of the optimal Valley beater refined pulps are relatively high (348-423 ml), implying a benefit in forming process and manufacturing of pulp products.

2020 ◽  
Vol 30 (4) ◽  
pp. 335-343
Author(s):  
R Ashrafi ◽  
RM Saiem ◽  
M Kamruzzaman ◽  
MSAA Mamun ◽  
HA Begum

The use of agricultural waste is of great interest to sustainable agriculture. An investigation was carried out to evaluate the effects of compost and compost tea made from agricultural waste rice straw on the yield and quality of two horticultural crops strawberry and tomato. In strawberry experiment, six treatments were considered which wereT1: 100% soil (as a control), T2: 80% soil + 20% compost, T3: 60% soil + 40% compost, T4: 40% soil + 60% compost, T5: 20% soil + 80% compost & T6: 100% compost. Results revealed that number of fruit, fruit yield and total sugar (%)was increased with the increasing level of compost up to 80% after that decreased at 100% compost. The treatment T5: 20% soil + 80% compost gave the best results among the treatments to grow strawberry with good yield (185.3 g/plant) and sweetness (total sugar 5.19%). On the other hand, six treatments i.e. T1: Control, T2: Compost (5 t/ha), T3: Compost tea (50% concentration), T4: Compost (5 t/ha) + Compost tea (50% concentration), T5: Compost tea (100% concentration) and T6: Compost (5t/ha) + Compost tea (100% concentration) were considered in tomato experiment. As a result, it was observed that combined application of compost (5 t/ha) along with compost tea (100% conc.) (T6) gave the highest yield of tomato than not only control (T1) but also single application of compost or compost tea (T2, T3, T4&T5). Level of compost tea concentration also showed significant effect on fruit yield of tomato. Comparing between treatment T4 and T6, fruit yield was found higher (1027.67 g/plant) in treatment T6: Compost (5t/ha) + Compost tea (100% conc.) than 961.3 g/plant in T4: Compost (5 t/ha) + Compost tea (50% conc.). So, it could be summarized that use of rice straw as compost and compost tea affects positively both in two experiments. The results of this study confirm the beneficial effects of compost to increase the yield and sweetness of strawberry and combination of compost and compost tea to increase the yield of tomato. Progressive Agriculture 30 (4): 335-343, 2019


Holzforschung ◽  
2002 ◽  
Vol 56 (5) ◽  
pp. 513-521 ◽  
Author(s):  
M. Ristolainen ◽  
R. Alén ◽  
P. Malkavaara ◽  
J. Pere

Summary The effect of the partial removal of xylan on unbleached and bleached birch kraft pulps was investigated by Fourier transform infrared (FTIR) microspectroscopy and the resulting data were analyzed by multivariate data analysis, i.e., principal component analysis (PCA) and maximum likelihood principal component analysis (MLPCA). Isolated model substances (xylan, cellulose and lignin) were used to calibrate these methods. Clear chemical changes in the relative proportions of the main constituents and functional groups on the pulp fiber surface were observed as a function of the amount of xylan removed. In addition, due to the partial removal of xylan, indications of some physical changes were observed.


Author(s):  
Shohreh Ariaeenejad ◽  
Atefeh Sheykhabdolahzadeh ◽  
Morteza Maleki ◽  
Kaveh Kavousi ◽  
Mehdi Foroozandeh Shahraki ◽  
...  

Abstract Background: Lignocellulosic biomass, is a great resource for the production of bio-energy and bio-based material since it is largely abundant, inexpensive and renewable. The requirement of new energy sources has led to a wide search for novel effective enzymes to improve the exploitation of lignocellulose, among which the importance of thermostable and halotolerant cellulase enzymes with high pH performance is significant. Results: The primary aim of this study was to discover a novel alkali-thermostable endo-β-1,4-glucanase from the sheep rumen metagenome. Using a multi-step in-silico analysis, primary candidates with desired properties were found and subjected to cloning, expression, and purification followed by functional and structural characterization. The enzymes' kinetic parameters, including V max , Km, and specific activity, were calculated. The PersiCel4 demonstrated its optimum activity at pH 8.5 and a temperature of 85°C and was able to retain more than 70% of its activity after 150 hours of storage at 85°C. Furthermore, this enzyme was able to maintain its catalytic activity in the presence of different concentrations of NaCl, MgCl 2 , CaCl 2 , and MnCl 2 . Our results showed that treatment with MnCl 2 could enhance the enzyme’s activity by 89%. PersiCel4 was ultimately used for enzymatic hydrolysis of autoclave pretreated rice straw, the most abundant agricultural waste with rich cellulose content. In autoclave treated rice straw, enzymatic hydrolysis with the PersiCel4 increased the release of reducing sugar up to 260% after 72 hours in the harsh condition ( T= 85°C, pH = 8.5). Conclusion: Considering the urgent demand for stable cellulases that are operational on extreme temperature and pH conditions and due to several proposed distinctive characteristics of PersiCel4, it can be used in the harsh condition for bioconversion of lignocellulosic biomass.


2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Eryani . ◽  
Sri Aprilia ◽  
Farid Mulana

<p>Agricultural waste such as rice straw, rice husk and rice husk ash have not been utilized properly. This waste of agricultural produce can actually be used as an alternative to bionanofiller because it contains an excellent source of silica. The silica content contained in the rice waste when combined with the polymer matrix can produce composites having high thermal and mechanical properties. Characterization of bionanofiller from this rice waste is done by SEM, XRF, FTIR, XRD and particle density. The result of SEM analysis from this rice waste is feasible to be used as filler because it has size 1 μm. Likewise with the results of XRF analysis that rice waste contains a high enough silica component that is 80.6255% - 89.83%. FTIR test results also show that bionanoparticles from rice waste have the same content of silica. In the XRD analysis the best selective gain of rice waste is found in rice husk ash which is characteristic of amorp silica at a range of 2ϴ = 22<br />. The largest density analysis of paddy waste was found in rice husk 0.0419 gr / cm , followed by rice straw by of 0.0417 gr / cm 3 and rice hulk ash 0.0407 g / cm 3</p>


2020 ◽  
Author(s):  
Rehab Metwally ◽  
hassan Abu Hashish ◽  
Haitham Abd El-Samad ◽  
Mostafa Awad ◽  
Ghada Kadry

Abstract Background: The world depends almost on fossil fuels. This leads to depletion of oil and an increase in environmental pollution. Therefore, the researchers search to find alternative fuels. Waste cooking oil (WCO) was selected as feedstock for biodiesel production to eliminates the pollution problems. The agricultural waste is very big and without cost, this leads to the use of the rice straw in preparing a catalyst for biodiesel production. Results: The reusability of the acidic catalyst confirmed that the conversion efficiency was high until after 8 cycles of the production. The highest conversion efficiency of the converting WCO extended to 90.38% with 92.5% maximum mass yield and methyl ester content 97.7% wt. at the optimized conditions. The result was indicating that B15 is the best blend for thermal efficiency and specific fuel consumption. All emission concentrations decrease with increasing the engine load, especially for B15 fuels compared to the diesel oil.Conclusion: The novelty of this paper is assessing the methyl esters from the local WCO as an alternative fuel for diesel engines using a heterogeneous catalyst based on the agricultural waste. The performance of the diesel engines and its exhaust emissions have been experimentally investigated with the produced biodiesel of WCO as a blend (B10, B15, and B20) compared to the diesel.


Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5730
Author(s):  
Xianxian Qin ◽  
Jixin Luo ◽  
Zhigao Liu ◽  
Yunlin Fu

Rice straw is a common agricultural waste. In order to increase the added value of rice straw and improve the performance of rice straw biochar. MgO-modified biochar (MRBC) was prepared from rice straw at different temperatures, pyrolysis time and MgCl2 concentrations. The microstructure, chemical and crystal structure were studied using X-ray diffraction (XRD), a Scanning Electron Microscope (SEM), Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption desorption isotherms and Elementary Analysis (EA). The results showed that the pyrolysis temperature had significant influence on the structure and physicochemical property of MRBCs. MRBC-2 h has the richest microporous structure while MRBC-2 m has the richest mesoporous structure. The specific surface area (from 9.663 to 250.66 m2/g) and pore volume (from 0.042 to 0.158 cm3/g) of MRBCs increased as temperature rose from 300 to 600 °C. However, it was observed MgCl2 concentrations and pyrolysis time had no significant influence on pore structure of MRBCs. As pyrolysis temperature increased, pH increased and more oxygen-containing functional groups and mineral salts were formed, while MgO-modified yield, volatile matter, total content of hydrogen, oxygen, nitrogen, porosity and average pore diameter decreased. In addition, MRBCs formed at high temperature showed high C content with a low O/C and H/C ratios.


2007 ◽  
Vol 546-549 ◽  
pp. 241-244 ◽  
Author(s):  
Yun Qi Yan ◽  
H. Zhang ◽  
Q. Chen ◽  
H. Zhong ◽  
W.P. Weng

Rolling and punching techniques of AZ31 alloy were investigated in this paper. Various rolling experiments were carried out to make fine-grained Mg sheets. Punching tests were conducted at the temperatures range from 70 to 300 oC. The analysis revealed that there existed an excellent warm forming temperature for as-rolled AZ31 alloy. A warm deep punching tool setup using heating elements was designed and manufactured to produce the cell phone. Microstructures were observed using optical and scanning electron microscope equipped with EBSD. The textures in as-rolled and as-annealed specimens attribute to different mechanical properties along the various direction.


2013 ◽  
Vol 812 ◽  
pp. 151-156 ◽  
Author(s):  
Mohd Syazwan Ramle ◽  
Ahmad Zafir Romli ◽  
M.H. Abidin

Rice husk is an agricultural waste produced in bulk quantity as a part of rice milling. There have been many approaches in utilizing rice husk as fillers in polymer composite. However, recycled PVC has not been reported to be used in PVC/rice husk composites yet. In this research, a good interfacial interaction between rice husk and recycled polyvinylchloride has been achieved by incorporation of aminosilane as coupling agent. The aminosilane treated recycled polyvinyl chloride was mixed with rice husk and then fabricated by using hot compression moulding. Three different ratio of rice husk to recycled polyvinyl chloride were used which is 65/35, 55/45 and 45/55 as shown in Table 1. The positive effect of rice husk reinforcement as well as surface treatment has been reflected in the improved tensile properties of the resulting polyvinyl chloride based composite. However, flexural stress of the treated composite drops with increasing filler percentage. The incorporation of aminosilane as coupling agent increases the tensile stress of 45 wt% of rice husk significantly. Scanning electron microscopy has been used to understand the failure mechanisms of aminosilane modified rice husk filled recycled polyvinylchloride composites. The findings can be used to increase the effort in recycling rice husk and PVC.


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