SOME OBSERVATIONS FROM STUDIES OF RF PLASMA PYROLYSIS OF WASTE TIRES

Pyrolysis treatment of waste tires was studied in a capacitively-coupled radio frequency (RF) plasma reactor. Using RF input power between 1600 and 2000 W and a reactor pressure between 3000 and 8000 Pa, a reactive plasma environment with a temperature between 1200 and 1800 K can be reached. Under these conditions, pyrolysis experiments with tire powder showed that two product streams were obtained: a combustible gas and a pyrolytic char. The main gaseous components were H₂, CO, and CH₄. When adopting double sets of electrodes in this plasma reactor, the gas yield and concentrations of H₂ and CO can be enhanced. The energy utilization efficiency of this RF plasma pyrolysis reactor system was also analyzed.     

Steam thermolysis of discarded tires: testing and analysis of the specific fuel consumption with tail gas burning,steam generation,and secondary waste slime processing

This paper presents the process of steam thermolysis of shredded used tires for obtaining from them liquid fuel and technical carbon carried out in a screw reactor with heating due to the partial burning of obtained fuel and burning of the tail combustible gas. The features and advantages of using steam for safety and stability of the process, including the problem of secondary waste slime processing, have been considered. The specific fuel consumption and the steam generation per 1 kg of processed tires and, separately, the gas consumption for power supply (heating) of the process without using fuel, as well as with additional burning of fuel for processing slime together with tires, have been considered. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 82, No. 2, pp. 242–251, March–April, 2009.     

有限元方法用于预报轮胎的侧偏特性

分析了影响轮胎胎侧偏特性的理论模型分析精度低的几个因素,采用有限元分析手段弥补理论模型缺陷,建立了能够考虑轮胎实际结构的侧偏特性分析模型,不但提高了分析精度,而且能够对多种型号轮胎进行侧偏特性预报。计算结果表明轮胎侧偏特性与试验数据吻合较好,说明此方法预报轮胎侧偏特性的有效性,并为轮胎的结构优化及改进侧偏特性提供了一种有效的分析方法。     

Characterization and photo-Fenton treatment of used tires leachate

In this study the leachates derived from used tires were firstly characterized by means of the evaluation of their organic matter content. The leachate from tire powder presented a COD value of 508 mg O(2) l(-1) and a TOC of 214 mg Cl (-1). The main identified organic substances were constituents of the rubber structure: benzothiazole derivatives, phthalates, phenolic derivatives, hydrocarbons and fatty acids. The application of photo-Fenton treatment was investigated in order to obtain the maximum organic matter removal. When a solar chamber as light source was used (light intensity=500 Wm(-2)), the best operational conditions were the following: [H(2)O(2)]=3703 mg l(-1), [Fe(2+)]=92.1 mg l(-1), initial pH 2.7-3.0, reaction time=100 min. After the photo-Fenton treatment at optimum conditions, the reached COD and TOC reduction was 64% and 48%, respectively. The main initial organic substances were eliminated after the reaction and no significant by-products were identified. A complementary treatment consisted of coagulation-flocculation carried out with FeCl(3) x 6H(2)O at pH 12 produced a maximum organic matter removal of 43% as COD and 39% as TOC. A combination of photo-Fenton followed by coagulation-flocculation enhanced the organic matter removal: a reduction of 77% of COD and 64% of TOC was attained.     

轮胎专用复合天然橡胶的发展趋势

轮胎专用复合天然橡胶是专门用于轮胎生产加工的天然橡胶的特殊称呼,这类橡胶产品的工艺技术是对传统的天然橡胶初加技工艺术的革新和改造。该类产品从工艺流程、产品质量、市场竞争力都比以往的天然橡胶标准产品更受下游厂家的认可,有更大的竞争优势。但它的发展也面临着重重困难,包括从原料控制、工艺监督、成品销售等方面还需要等待实践的检验、产业的规划发展等多重因素的影响。对轮胎专用复合天然橡胶的发展进行中长期发展规划,让它的发展能在市场上占有一席之地,这是对现有橡胶初加工企业的一种升级改造,也不断促进天然橡胶产业经济可持续发展。     

轮胎带束设计对滚动阻力的影响

研究只调整轮胎的带束角度或材料对轮胎滚动阻力的影响。试验结果表明,在同样的条件下,带束角度的变化,轮胎的滚动阻力会相应发生变化,带束角度增大,轮胎滚阻增大;在同样的条件下,带束材料的强度变化,轮胎的滚动阻力会相应发生变化,带束材料强度增大,滚阻降低;同时轮胎重量增大,轮胎滚动阻力增大。     

195/85R16LT全钢丝轻型载重公制子午线轮胎的设计

介绍195/85R16LT全钢丝轻型载重公制子午线轮胎的设计。结构设计:外直径735mm,断面宽199mm,行驶面宽度154mm,行驶面弧高6.5mm,胎圈着合直径404mm,胎圈着合宽度152.4mm,断面水平轴位置(H1/H2)1.0307,花纹深度10.5mm,花纹饱和度78%,花纹周节数56,采用直线型花纹设计。施工设计：胎体采用3+9*0.22+0.15钢丝帘线,1_#和2_#带束层采用3*0.2+6*0.35HT钢丝帘线, 3_#带束层采用3*4*0.22HE钢丝帘线;采用两鼓一次法成型机成型,硫化机硫化。成品性能试验结果表明,成品轮胎的充气外缘尺寸和强度性能符合相应设计和国家标准要求,耐久性能符合企业标准要求。     

生物质与废轮胎共热解对热解液体性质的影响

研究了影响生物质与废轮胎共热解得到的液体性质及组成的因素。结果表明生物质和废轮胎最大热分解温度均发生在330~360℃,共热解能够产生协同效应。随着加热速率的增大,最大热分解温度逐渐向高温处移动;生物质比例越低热解得到的液体越多;温度越高,得到的液体越少,在350℃下进行共热解得到的液体最多。混合后热解液体的氧含量比生物质单独热解得到液体的氧含量有所降低,芳香族化合物有所增加,并分析了热解液体的族组成。     

Evaluation of pyrolytic oil from used tires and natural rubber (Hevea brasiliensis)

The pyrolysis of used tires, UT, and natural rubber (Hevea brasiliensis), NR obtained from Nigerian NIG800 clonal rubber tree, was performed and the effects of process conditions on product yield were investigated. An optimum yield was attained at operating temperature of 600°C, a heating rate of 15°C?min^?1, for a feed size of 6?mm. The UT and NR gave maximum pyrolytic oil yield of 34.40 and 75.93?wt%, respectively. The pyrolytic oil was characterized using Fourier transform infrared, nuclear magnetic resonance, and gas chromatography–mass spectrometry (GC–MS). Results obtained reveal the pyrolytic oil to be a complex mixture, mainly of aliphatic and aromatic compounds, which can serve as feedstock for industrial application. Nevertheless, a comparative evaluation of the physical and chemical properties of the UT and NR pyrolytic oil showed that NR had hydrocarbon composition of 80% aliphatics, 12% aromatics (with less than 2% polycyclic aromatic hydrocarbon concentration). However, the UT pyrolytic oil had 42% aliphatic and 34% aromatic compounds (with polycyclic aromatic hydrocarbons concentrations of 18%). Also, NR pyrolytic oil had better physical properties such as density, viscosity, flash point, pour point, and higher heating value than that produced from UT in this study, and comparable with that of commercial diesel. Moreover, sulfur content, which is a limiting factor in the direct combustion of UT pyrolytic liquid, was absent in NR pyrolytic oil. Hence, it is technologically feasible for NR from H. brasiliensis to be a suitable source of pyrolytic oil than UT.     

Profit Increasing while Inventory Rising Utilization of Waste Rubber being Restricted by Slowdown of Market of Rubber Products

According to the statistics of Waste Rubber Comprehensive Utilization Branch of China Rubber Industry Association, in the first seven months of this year, for 38 key member enterprises, the realized profit had a year-on-year growth of 14.96%; meanwhile, the inventory of reclaimed rubber enterprises had a year-on-year growth of 83.22%, influenced by macro environment, the price of waste rubber decreased by nearly half, and the operation of the acquisition industry was at a low ebb.