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81.
In this work, we aim to analyse the capability of using a 16-segmented Electrical Capacitance Tomography (ECT) sensor system to monitor the internal composition of a chemical process conveyor that carries crude palm oil (CPO) multiphase flow. The source used to excite the electrodes is a differential potential, instead of the conventional single potential source, in order to obtain an improved sensitivity of the sensor, especially in the central area of the pipe. This system aims to recognise the phase concentration of the flow. The attained concentration profile that is received from the capacitance measurements is capable of providing an image of the liquid and liquid mixture in the pipeline, making the separation process (between oil and liquid waste) much easier and the CPO's quality can be dependably monitored. Experimental results and analysis are presented, and the new excitation technique is shown to provide better sensor sensitivity in the central pipe area. The visualisation results deliver information regarding the flow regime and concentration distribution in a two-phase flow-rate measurement system incorporating a liquid flow-measuring device. The information obtained will assist the design of process equipment, and the verification of existing computational modelling and simulation techniques. 相似文献
82.
Empty fruit bunch (EFB) from oil palm is one of the potential biomass to produce biofuels like bio-oil due to its abundant supply and favorable physicochemical characteristics. Confirming the assertion, this paper presents an overview of EFB as a feedstock for bio-oil production. The fundamental characteristics of EFB in terms of proximate analysis, ultimate analysis and chemical composition, as well as the recent advances in EFB conversion processes for bio-oil production like pyrolysis and solvolysis are outlined and discussed. A comparison of properties in terms of proximate analysis, ultimate analysis and fuel properties between the bio-oil from EFB and petroleum fuel oil is included. The major challenges and future prospects towards the utilization of EFB as a useful resource for bio-oil production are also addressed. 相似文献
83.
Hossein Sarbaz Hossein Ghiassian Ali Akbar Heshmati 《International Journal of Pavement Engineering》2014,15(7):577-583
This paper investigates the effect of including randomly spaced palm fibres in a soil matrix. The fibres in date palm have special properties such as low costs, plenitude in the region, durability, lightweight, high tension capacity and relative strength against deterioration. Thus, it is possible to use the palm fibres as an alternative low-cost natural material for soil reinforcement. As the objective of this research was to mix the soil and date palm fibres to use in the construction of soil roads, especially village road, we discuss the influence of date palm fibres on CBR (California Bearing Ratio) strength of fine sand. CBR tests were conducted under dry and submerged conditions. The durability of fibres was also investigated using the plain fibres and fibres coated with bitumen. Some samples were soaked for several months before being loaded. The results show that the addition of palm fibres increases the CBR strength of the sand specimens significantly. It is also seen that the sliding strength controls the failure of the specimens rather than the rupture strength. 相似文献
84.
In this work, three residues from the food industry (coconut husk, defatted grape seed and pressed palm fiber) were subjected to subcritical water hydrolysis with the aim of producing fermentable sugars. Hydrolysis kinetics were determined using a semi-batch unit equipped with a 50 mL reactor. The process was conducted at 208 °C and 257 °C for 30 min, with water flow rate of 33 mL/min and under 20 MPa. The liquefaction degree of the raw materials increased with temperature. The total reducing sugars recovered also increased with temperature. Maximum total reducing sugars recovered for coconut husk, defatted grape seed and pressed palm fiber using SWH were 11.7%, 6.4% and 11.9% from total raw material, respectively. Coconut husk presented the highest amount of monosaccharides (3.4%), followed by pressed palm fiber (2.4%) and defatted grape seeds (0.7%). On the other hand, the degradation products that are also fermentation inhibitors increased with temperature as well. Each raw material presented a different monosaccharides and inhibitors profile, which indicates that SWH should be evaluated and optimized individually for each case. 相似文献
85.
Abdelkarim Mahdhi Abir Bahi Dorra Mzah Amina Bakhrouf 《Journal of the science of food and agriculture》2013,93(15):3850-3855
86.
《Measurement》2014
The objective of this study was to evaluate variation of mechanical and physical properties of binderless particleboard panels manufactured from raw material of young and old oil palm (Elaeis guineensis) trunks. Results revealed that such experimental panels made from particles of young oil palm trunks had higher mechanical characteristics than those of made from old trunks. Addition of sugar compounds in the samples produced having particles from young trunks with and without extracted material enhanced their bending and internal bond strength values. Overall dimensional stability in the form of thickness swelling and water absorption those panels made from young trunks was adversely influenced. However adding sugars in the samples improved their thickness swelling and water absorption in both cases of with and without applying of extraction process. 相似文献
87.
水资源短缺已经是21世纪全球性的重大问题,如何解决水资源短缺问题迫在眉睫.清晨挂满硕大水滴的蜘蛛网为解决水资源短缺问题提供了一个良好的思路.全面总结了仿蛛丝纤维集水领域的研究进展,重点介绍了仿蛛丝纤维的常见制备方法,包括瑞利不稳定法、电动力学技术和微流控法,详细划分了各类制备方法的子类,并对每一种方法的制备步骤、原理和优缺点进行了详细介绍.同时,详细介绍了仿蛛丝纤维集水的主要原理,包括拉普拉斯压力差、表面能梯度、滞后效应、悬挂能力和交叉结构受力原理,为集水工程与技术的开发和改进提供了理论基础.另外,介绍了单根仿蛛丝纤维集水、纤维交叉结构集水和大规模集水等仿蛛丝微纤维的集水行为.最后,对仿蛛丝纤维集水的未来发展方向进行了分析和展望.将有助于全面了解仿蛛丝纤维的制备方法、集水机理及集水行为,对集水效率的提高、油水分离、材料界面、流体控制和功能材料等领域的发展起到促进作用. 相似文献
88.
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90.
Zainab Z. Ismail 《The International journal of environmental studies》2013,70(1):135-149
The presence of excessive amounts of nutrients including phosphates in water is undesirable. They cause the deterioration of water quality and problems in many natural and engineering systems. The recycling of agricultural waste materials as biosorbents for contaminants removal provides a cheap and ecological means to reduce wastes. This study explored the use of date palm wastes for the effective removal of phosphate from aqueous solutions. Granular date stones (GDS) and palm surface fibres (PSF) as raw abundant waste materials were examined for PO4 -3 removal from aqueous solution. The experimental work was performed in a batch mode to investigate the influence of initial phosphate concentration, contact time, and pH of solution on phosphate biosorption. The FT-IR spectra for the waste materials display many adsorption peaks, confirming the complex nature of the GDS and PSF. Phosphate percentage removal up to 87 and 85% were obtained at initial PO4 -3 concentration of 50 mg as P/L using GDS and PSF, respectively. Due to their low cost and high capability, these types of waste can be used for cost-effective removal of phosphate from wastewater. 相似文献