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991.
Application of Artificial Neural Networks for Evaluating Pressure Filtration of Coal Refuse Slurries
Gireesh S. S. Raman Mark S. Klima 《Mineral Processing and Extractive Metallurgy Review》2017,38(1):47-53
Bench-scale pressure filtration testing was performed to evaluate the dewatering characteristics of two coal refuse slurries, which were collected from thickener underflow streams of two coal preparation plants. Pressure filtration provides an opportunity to produce drier solids (filter cake) that can be stacked or mixed with the coarse refuse and improved water (filtrate) recovery that can be reused in the plant. This paper examines the effects of some of the major influencing variables such as pressure, slurry pH, feed solids concentration, fines fraction of solids in the slurry, filtration time, and temperature on dewatering thickener underflow slurry. Experimental results indicated that the overall filtrate flux increased with increase in pressure and temperature while it decreased with increase in fines fraction, pH, filtration time, and solids concentration. A total of 82 experimental results were used to develop a feed forward back-propagating artificial neural network (ANN) model. The model had R2 values over 0.9 for both the training and the testing datasets, indicating the goodness of fit. Sensitivity analysis performed using the ANN model indicated that filtration time and pH were the most significant variables influencing filtrate flux. 相似文献
992.
The effects of particle size, impeller clearance and impel er speed are assessed to show how condition variations influence power consumption in the water-solid slurry suspension in an agitated tank. The energy efficiency of slurry height variation, impel er type and diameter, and solid movement speed has been investigated with six soil series stirred in a soil-water slurry. Coarser sand particles are observed to significantly increase power consumption, while finer particles, for instance clay, decrease the stirring power requirement. The 3-blade HR100 SUPERMIX? impeller manufactured by SATAKE general y performs more efficiently than a conventional 4-pitched blade turbine. The impeller's geometric design, including diameter and number of blades influences the impeller's energy efficiency, and HR100 impellers with greater diameters remarkably reduce power consumption. The tests demonstrated that the power required to provide off-bottom solid suspension and solid dispersion can be reduced dramatically by increasing the slurry height rather than by accelerating the impel er, if this option is possible. 相似文献
993.
巨菌草沼渣制备液化多元醇及合成聚氨酯的研究 总被引:1,自引:0,他引:1
以巨菌草经厌氧沼气发酵后产生的沼渣为原料,在聚乙二醇(PEG400)和丙三醇的混合溶剂中进行液化制备液化多元醇。研究了液化条件对液化效果的影响。结果表明:巨菌草沼渣最佳液化条件为液化试剂PEG400/丙三醇(质量比)1.5:1、液化温度160℃、液化时间1.5h、液固比(质量比)2.9:1、催化剂浓硫酸用量为液化试剂质量5%。在此条件下,沼渣液化效果最好,制得的液化多元醇羟值为498mg/g,适用于聚氨酯硬质泡沫的生产。用液化多元醇部分代替聚醚多元醇制备聚氨酯材料,质量比为1:1时,所得材料性能最佳,密度和压缩强度分别为38.7kg/m3和0.21MPa。 相似文献
994.
长远来看,原油重劣质化的发展趋势不可避免,能够实现渣油清洁高效转化的深度加氢裂化技术是应对这一挑战的关键,正逐渐成为炼厂最主要的渣油加工技术手段。本文介绍了渣油沸腾床加氢裂化和渣油悬浮床加氢裂化技术的应用现状,结合技术特点和技术经济指标进行了对比分析,进一步综述了两种渣油加氢裂化技术的研发新进展。文中指出渣油沸腾床加氢裂化技术是目前最为成熟的渣油高效转化技术,未来仍将在渣油高效加工利用方面发挥重要作用,其中组合集成工艺以及未转化塔底油的处理工艺是其研发和应用的重点。渣油悬浮床加氢裂化技术具有高转化率的优势,但在工业化应用方面尚不如沸腾床成熟和普遍,仍需继续开发高活性、高分散的催化剂以及着重解决装置结焦问题,未来发展前景看好。 相似文献
995.
996.
997.
为减缓液态浆状分散染料静置后染料颗粒的聚集沉淀,以150%LB分散黑浆为原料,采用高速剪切分散的方法研究了尿素增溶对分散染料黑浆性能的影响。结果表明:增加分散剂MF和尿素用量及调节分散黑浆p H值可减缓浆料的沉淀速度,质量分数为50%的尿素的加入使浆料静置60 d的沉淀度从86.04%降低到75.18%;加入质量分数为50%的尿素,分散黑浆LB的3只单色料分散橙288、分散紫93∶1和分散蓝291∶3的离心稳定性分别提升39.9%~42.19%、29.06%~29.99%和26.78%~27.38%,上染率分别提高2.08%~2.19%、0.73%~1.1%和0.72%~0.99%,织物的K/S值从9.782提升到9.876;同时,尿素的加入降低了分散染料颗粒的平均粒径。 相似文献
998.
999.
电解水煤浆制氢在能源消耗与产氢效率上都更优于电解水过程,并且在电解过程中可以同时达到对矿石能源净化的目的,是一种十分值得推广与发展的产氢新技术。本文在综述电解水煤浆技术现状及特点的基础上,阐述了电解水煤浆制氢技术的原理,并以此为理论基础概述了反应温度、电解质种类、样品预处理对电解水煤浆制氢的影响,综述了国内外电解水煤浆电极材料的研究进展,并对电解水煤浆技术的发展现状和存在的不足进行了分析与展望。指出电解水煤浆技术发展的重点方向为:降低电解水煤浆过程中的能量消耗,多使用可再生能源;深入研究反应机理,提高产氢效率,实现化学能与电能耦合向氢能的转变;改善电极的稳定性和耐腐蚀性,使电极更加耐久并降低电极成本;通过研究新型催化电极与催化剂来提高反应的效率。 相似文献
1000.
Ayhan Demirbas Osman Taylan Durmus Kaya 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(20):3027-3033
Biogas is produced by anaerobic (oxygen free) digestion of organic materials such as sewage sludge, animal waste, and municipal solid wastes (MSW). As sustainable clean energy carrier biogas is an important source of energy in heat and electricity generation, it is one of the most promising renewable energy sources in the world. Biogas is produced from the anaerobic digestion (AD) of organic matter, such as manure, MSW, sewage sludge, biodegradable wastes, and agricultural slurry, under anaerobic conditions with the help of microorganism. Biogas is composed of methane (55–75%), carbon dioxide (25–45%), nitrogen (0–5%), hydrogen (0–1%), hydrogen sulfide (0–1%), and oxygen (0–2%). The sewage sludge contains mainly proteins, sugars, detergents, phenols, and lipids. Sewage sludge also includes toxic and hazardous organic and inorganic pollutants sources. The digestion of municipal sewage sludge (MSS) occurs in three basic steps: acidogen, methanogens, and methanogens. During a 30-day digestion period, 80–85% of the biogas is produced in the first 15–18 days. Higher yields were observed within the temperature range of 30–60°C and pH range of 5.5–8.5. The MSS contains low nitrogen and has carbon-to-nitrogen (C/N) ratios of around 40–70. The optimal C/N ratio for the AD should be between 25 and 35. C/N ratio of sludge in small-scale sewage plants is often low, so nitrogen can be added in an inorganic form (ammonia or in organic form) such as livestock manure, urea, or food wastes. Potential production capacity of a biogas plant with a digestion chamber size of 500 m3 was estimated as 20–36 × 103 Nm3 biogas production per year. 相似文献