无害化城市生活垃圾直接气化熔融焚烧技术的试验研究

通过试验研究,开发出了一种新型的无害化城市生活垃圾直接气化熔融焚烧技术,其工艺流程为:将配好料的生活垃圾直接置于温度为1300～1500℃,炉内气氛为还原性的气化熔融焚烧炉中进行处理,助燃粉煤由炉子底部喷人,可燃气体产物进入二次旋风燃烧室完全燃烧后进行余热发电或供热;熔融渣和金属或从一个渣口中排出并被水急速冷却,被冷却的熔融渣和金属经分选机分选出金属和无机残渣,金属回收利用,无机残渣则作为建材;或分别从金属口和熔融渣口排出,金属回收利用,熔融渣经水淬后再生利用。该炉的基建投资和运行费用比国外研制的垃圾直接气化熔融炉要低得多,一般只需国外的65％～85％。原垃圾中99.8％以上的二恶英可被分解,烟气中二恶英的排放量≤0.01 ng-FEQ/m3,熔融渣中二恶英的排放量≤0.003 ng-TEQ/g。     

污泥干燥焚烧一体化中热量计算的探讨

介绍了几种常用的污泥干燥焚烧一体化技术及其设备,分析了污泥在转筒干燥-循环流化床焚烧一体化设备中的热量输入、输出过程,对污泥干燥以及焚烧设备的设计有一定的参考价值。     

日本放射性同位素废物的焚烧处理

介绍了日本放射性同位素废物焚烧设施的工艺系统（包括进料子系统、焚烧子系统和烟气净化及冷却子系统）的主要流程、设备、运行管理,以及焚烧技术的发展方向。     

Incineration and gasification technologies completed with up-to-date off-gas cleaning system for meeting environmental limits

It is shown how gasification can be used for processing wastes including “waste to energy” system. First, an analysis of incineration of wastes taking into account environmental limits is performed. This analysis is aimed at a typical arrangement of a conventional oxidizing incineration plant consisting of waste storage and feeding systems, two-stage incinerator (primary and secondary combustion chambers), heat recovery system involving co-generation and off-gas cleaning system. It is also focused on a new arrangement where the primary combustion chamber (rotary kiln) is substituted by gasification reactor. The proposed concept with a fluidised bed reactor utilizes results of experimental research with various mixtures of wastes (e.g. shredded textile and rubber) considering typical conditions of operation. Experiments provide us with various important characteristics (heat value of produced syngas vs. temperature in the gasification reactor, temperature in the secondary combustion chamber vs. oxygen concentration in outlet flue gas and heat value of syngas, etc.). Then it is possible to make a comparison of conventional incineration and gasification for a concrete industrial process involving a unit for thermal treatment of hazardous industrial waste mixed with municipal solid wastes with capacity of 10,000 t/year. The application of gasification technology brings about the whole range of benefits like minimizing the consumption of auxiliary fuel and decreasing size of the secondary combustion chamber and other subsystems of the incineration plants. Involving such a system with energy and investment cost reduction into an industrial process contributes to meeting cleaner production and environmental legislation regulations.     

Effects of particulates, heavy metals and acid gas on the removals of NO and PAHs by V2O5–WO3 catalysts in waste incineration system

This study investigated the activities of prepared and commercial V₂O₅–WO₃ catalysts for simultaneous removals of NO and polycyclic aromatic hydrocarbons (PAHs) and the influences of particulates, heavy metals, SO₂, and HCl on the performances of catalysts. The experiments were carried out in a laboratory-scale waste incineration system equipped with a catalyst reactor. The DREs of PAHs by prepared and commercial V₂O₅–WO₃ catalysts were 64% and 72%, respectively. Increasing the particulate concentrations in flue gas suppressed the DRE of PAHs, but increasing the carbon content on surface of catalysts promotes the NO conversions. The DRE of PAHs by the catalysts was significantly decreased by the increased concentrations of heavy metal Cd, but was promoted by high concentration of Pb. The influence level of SO₂ was higher than HCl on the performances of V₂O₅–WO₃ catalysts for PAHs removal, but was lower than HCl for NO removal. Prepared and commercial V₂O₅–WO₃ catalysts have similar trends on the effects of particulates, heavy metals, SO₂, and HCl. The results of ESCA analysis reveal that the presences of these pollutants on the surface of catalysts did not change the chemical state of V and W.     

Inhibition and promotion: The effect of earth alkali metals and operating temperature on particle agglomeration/defluidization during incineration in fluidized bed

Some studies have demonstrated that earth alkali metals promote agglomeration; however, others have shown that they inhibit the generation of agglomeration. The earth alkali metals (Mg and Ca) may cause both inhibition and promotion of agglomeration/defluidization. Therefore, this study focuses on the effect of Mg, Ca and the operating temperature on the agglomeration/defluidization of sodium during incineration in a fluidized bed reactor. The results indicate that the added Mg and Ca inhibit agglomeration and increase the defluidization time. At low Na/Mg and Na/Ca mole ratios, Mg and Ca inhibit defluidization significantly. However, the inhibition reduces as the concentration of Na increases. When the mole ratio (Na/Mg and Na/Ca) exceeds two, the inhibition of Mg and Ca is not apparent. Under these conditions, the operation temperature is the main factor with regard to agglomeration/defluidization. When Mg and Ca are added to reduce the agglomeration/defluidization, both the concentration of Na and operating temperature must be considered.     

生活垃圾焚烧发电厂烟气处理工艺的分析探讨

生活垃圾焚烧厂的烟气处理系统主要是对酸性气体、氮氧化物、颗粒物、有机物及重金属等进行控制。烟气处理工艺主要有干法、半干法和湿法三种工艺。通过对国内长三角地区典型的生活垃圾焚烧厂烟气处理工艺的详细研究发现,采用"半干法+活性炭喷射+布袋除尘器"完全可以达到欧盟92标准。影响烟气排放指标的其他因素:生活垃圾来源的不同、焚烧炉的型式不同和焚烧厂实际运营对其影响。     

放射性废油焚烧处理的可行性研究

本文介绍了放射性废油焚烧处理的可行性研究试验 ,试验主要包括废油的物性测定、预处理及喷雾焚烧实验。对于可能混有汽油等低闪点成分的放射性废油 ,推荐采用添加煤油来降低粘度的预处理方法。喷雾焚烧试验表明 ,对于粘度小于 30 m Pa· s的废油 ,在燃烧炉容积热强度低于 1.6× 10 6k J/ (m3 ·h)时 ,可以实现完全燃烧。在很宽的空气过量系数范围内 ,烟气中 CO浓度均低于 0 .1%。     

垃圾焚烧发电自动控制系统设计

垃圾焚烧发电是环境保护、资源再利用的发展趋势之一。本文根据垃圾焚烧发电的流程特点,提出了采用分布式3级结构计算机自动控制系统的设计,重点阐释了以两炉一机为例的垃圾焚烧发电厂计算机控制系统。     

Combustion characteristics of sewage sludge in an incineration plant for energy recovery

A new type of sewage sludge incinerator that combines a pressurized fluidized bed combustor and a turbocharger driven by flue gas was proposed. In this study, the operation and combustion characteristics of a demonstration plant were clarified, and the design data for a commercial plant were obtained. The steady operation exceeded 600 h in total. CO, NO_x, and N₂O emissions in the flue gas were less than half those of a conventional plant. At an incineration capacity of 100 t/day, an energy savings of approximately 50% can be achieved compared with a conventional plant because the forced draft fan (FDF), the induced draft fan (IDF) and the feed water pump are unnecessary. Also, pressurization allowed reduction of the combustor volume, so about 25% of supplementary fuel can be reduced. Consequently, CO₂ emissions originating from electric power consumption and supplementary fuel is expected to be reduced by about 40% annually compared with emissions from a conventional plant; in addition, the cost of fuel and electricity can be reduced by 23 million yen. Therefore, this advanced incinerator for sewage sludge can realize energy recovery and savings as well as a low environmental impact.