丙烯腈装置废液焚烧炉的低NOx燃烧设计

简要介绍了NOx的生成机理和目前流行的低NOx燃烧技术;以吉化丙烯腈装置废液焚烧炉为例,通过介绍其焚烧炉膛的一次燃烧段、还原段和燃尽段结构,分析了低NOx燃烧技术在丙烯腈装置废液焚烧炉设计中的运用.     

Refuse Decomposition in the Presence and Absence of Leachate Recirculation

A side by side comparison of two 8,000 metric ton test cells was performed to evaluate the effects of leachate recirculation on refuse decomposition at Yolo County, CA. After about 3 years of operation, refuse was excavated in three borings from the enhanced cell (E1, E2, and E3) and two borings from the control cell (C1 and C2). Refuse moisture content data show that leachate recirculation resulted in an increase in refuse moisture content, but also show that the refuse in the enhanced cell was not uniformly wet. The average moisture content in E1, E2, and E3 was 38.8, 31.7, and 34.8%, respectively, while the average moisture content in C1 and C2 was 14.6 and 19.2%, respectively. Leachate recirculation resulted in both higher methane yields, (63.1 versus 27.9 L CH4/wet-kg over 1231 days) and increased settlement (15.5% versus 3% of the waste thickness). The extent of decomposition of excavated refuse samples was determined by the biochemical methane potential (BMP) and the ratio of cellulose plus hemicellulose to lignin [(C+H)/Li]. Solids analyses showed the average BMP in the enhanced and control cells to be 24.0 and 30.9 mL CH4/dry-g, respectively. The corresponding (C+H)/Li ratios were 1.09 and 1.44, respectively. These data correlate well with the increased methane production in the enhanced cell. Thus laboratory and field data show more decomposition in the enhanced cell relative to the control cell. The refuse sampling program conducted for the Yolo County test cells, in concert with data on settlement, methane production, and the volume of liquid actually recycled, represents perhaps the most complete set of data available to date on a field-scale leachate recirculation landfill.     

垃圾焚烧厂主厂房土建设计应注意的问题

结合垃圾焚烧主厂房的广泛应用,针对卸料平台的标高设置问题、主厂房扩建问题和垃圾池问题,根据各种影响因素进行了多方案比选,得到了最佳解决方案,探讨了钢筋混凝土框架结构设计应注意的问题,可供同类工程参考。     

Fatigue Failure of 321 Stainless Steel Superheater Tubes from a Thermal Incinerator

Several boiler superheater tubes showed circumferential cracking at weld seams after 2 years in noncontinuous service (several shutdowns). On-site inspection revealed that several tubes were cracked and leaked; while many others were cracked, however, the severity was less pronounced. Two types of superheater tubes samples were collected: one with butt-welded tubes and the other with fillet-welded sleeve. The latter was found to be out of the boiler fireplace, and the sleeve was used as tubing support to the boiler shell. Detailed investigation showed that the butt-welded tubes contained circumferential fatigue cracks that initiated from the internal surface. The cracks initiated in the heat-affected zone and propagated as a result of tube vibration. The variations in the tube internal diameter and tube wall thickness are expected to play a role in tube fatigue failure. On the other hand, tubes with fillet-weld sleeve showed circumferential cracking as a result of fatigue crack initiation from weld defects on the tube external surface. The high vibration during several unscheduled shutdowns in addition to several other factors such as variations in tube inside diameter, wall thickness, and weld defects resulted in the initiation and propagation of fatigue cracks and premature failure. White deposits, similar to those observed when boiler tubes failed by caustic exposure, were seen in the vicinity of the tube cracks. Therefore, it was difficult to confirm whether the boiler tubes failed because of the fatigue cracks or because of the caustic salts (pH control chemical).     

新型污泥干化/焚烧技术的试验研究

采用新型喷雾干燥与回转式焚烧炉集成的污泥干化/焚烧工艺对萧山污水厂的脱水污泥进行处理试验.研究结果表明,新型干化焚烧技术及其装备具有热能综合利用效率高、安全性好、投资和运行成本低等特点.而且,经合适的烟气净化技术处理,气体污染物远低于<生活垃圾焚烧污染控制标准>(GB 18485--2001)的排放限值要求.     

城市垃圾焚烧底渣再生微粉强度特性的实验研究

为实现城市垃圾焚烧底渣的高效再生利用,进行了底渣及其再生微粉的物理、化学性质实验,采用不同比例底渣再生微粉替代水泥进行胶砂强度实验。结果表明：垃圾焚烧底渣再生微粉相比水泥材质更轻、颗粒更小、更均匀;再生微粉中以氧化物形式存在的Si、Al和Ca约占底渣总质量的70%,与水泥的化学成分组成类似,但SiO₂、Al₂O₃含量较高,而CaO含量较低。再生微粉内掺替代水泥的胶砂抗压、抗折强度均随替代比例的增加呈下降趋势;内掺30%时,再生微粉的强度活性指数可达55%以上,说明再生微粉具有一定的凝胶活性。此外,底渣再生微粉的掺加对胶砂早期强度的影响较小,随再生微粉掺量的增加,胶砂强度前期增长速度变慢,后期强度出现较大幅度的降低。     

垃圾焚烧飞灰研制硫铝酸盐水泥及其水化特性

以城市垃圾焚烧飞灰(以下简称焚烧飞灰)为主要原料,在实验室电炉里成功烧成了硫铝酸盐水泥熟料.研究了硫铝酸盐水泥熟料的烧成过程、组成及其形貌特征,并分析掺加适量石膏的硫铝酸盐水泥水化及重金属浸出特性.结果表明:将焚烧飞灰作为主要原料可以煅烧出以C4A3(-S)和C2S为主要矿物的硫铝酸盐水泥熟料,焚烧飞灰在生料中的掺量不...     

浅谈二段式垃圾焚烧炉燃烧自动控制技术

讨论了生活垃圾焚烧炉燃烧自动控制技术的原理,并以二段式垃圾焚烧炉自动化控制的实例流程说明它的技术应用。通过合理的参数控制,生活垃圾焚烧炉燃烧自动控制能达到成本控制的要求与绿色环保的要求。然而在该自动控制技术的应用中可以看到它的流程依然需要大量的人工干涉,人们需要生活垃圾焚烧炉燃烧自动控制技术向更加智能化方面发展。     

直燃式焚化炉的节能改造

当前覆铜板行业所使用的废气焚化炉有直燃式废气焚化炉和蓄热式废气焚化炉。蓄热式废气焚化炉的蓄热陶瓷体能够将燃烧机的热量储存起来,当蓄热陶瓷体的温度超过有机废气的着火点时,即使燃烧机不点火,炙热的蓄热陶瓷体也能点燃有机废气。介绍了直燃式（TO）焚化炉和燃气蓄热（RTO）焚化炉的原理和特点,广东深鑫电子材料有限公司的直燃式焚化炉改造为燃气蓄热（RTO）焚化炉,工程应用表明,可以降低燃油消耗,降低生产成本。     

200 t/d循环流化床焚烧炉垃圾及纸渣混烧运行实践

介绍了 200 t/d 垃圾、纸渣混烧流化床焚烧炉的设计及运行概况;根据运行及监测结果说明流化床焚烧炉处理生活垃圾及纸渣有燃烧效率高、负荷调节能力强、燃料适应性强、污染物排放低等方面的优势;并在实际运行过程中摸索出了一些可进一步改善和保证流化床焚烧炉稳定运行的经验。