垃圾化学链气化制备富氢合成气还原氧化球团研究

The Municipal Solid Waste (MSW) production is continuous increasing in China, resulting in serious environmental pollution. In addition, the low sponge iron production in China is attributed to the shortage of natural gas resource. This project therefore will utilize syngas produced from MSW to reduce the iron oxide pellet for sponge iron making, thereby declining environmental pollution and energy consumption, as well as improving the production of sponge iron..In this project, MSW is firstly converted to hydrogen-rich gas based chemical looping gasification. However, the main problems to limit its industrial application are:refractory tar and deactivated of the carrier. In view of the above problems, amodified carrier, good reactivity, which can as a tar reforming catalyst and CO2 capture will be prepared. In addition, MSW, bentonite and iron ore concentrate fines will be proportionally mixed to prepare green pellets while the influences of MSW amount on pellet quality will be investigated. The oxidized pellets will be prepared by oxidizing roasting, during which the operating parameters of oxidizing roasting are determined by changing oxidation system and roasting system, therefore confirming the consolidation mechanism of oxidized pellets. Finally, the oxidized pellets with and without MSW addition are reduced into sponge iron using syngas as reducing agent, during which the reduction performance differences.between oxidized pellets with and without adding MSW will be achieved by changing syngas atmosphere and reduction temperature. Moreover, the reduction model will be established. As a result, the oxide pellets reduction control modes and its mechanisms will be proposed.

大量的城市生活垃圾带来环境污染，与此同时，我国天然气短缺导致海绵铁产量严重不足。本项目利用生活垃圾化学链气化制备富氢合成气还原球团制备海绵铁。.首先利用垃圾化学链气化技术制备富氢合成气，针对化学链制气过程中焦油难降解、载体易失活问题，研发出良好反应活性的载碳体，通过完善化学链垃圾气化循环制富氢合成气技术，实现产气中CO2的捕获与强化制氢。其次，生球团造粒过程中添加垃圾，制备含/不含垃圾生球团，对生球团高温氧化焙烧制备含/不含垃圾氧化球团，通过对生球团和氧化球团的质量要求的控制，获得了内配垃圾的添加量范围，最后，将富氢合成气还原含/不含垃圾氧化球团制备海绵铁，揭示内配垃圾对球团还原性能影响的规律，以及阐明垃圾制备的富氢合成气对氧化球团还原反应的控制方式和机理。

大量的城市生活垃圾带来环境污染，与此同时，我国天然气短缺导致海绵铁产量严重 不足。本项目利用生活垃圾化学链气化制备富氢合成气还原球团制备海绵铁。.通过本研究得到球团垃圾添加量为2%最合适，含垃圾生球团及不含垃圾生球团的落下强度分别为4.2次/0.5m，2.1次/0.5m；抗压强度分别为14N/个，9.1N/个；爆裂温度分别为773K，453K。对生球团进行预热焙烧制作氧化球团，含垃圾氧化球团及不含垃圾氧化球团抗压强度分别为6.9kN/个，12.6kN/个。得到的球团符合工业生产要求。垃圾合成气及垃圾合成气还原球团时，还原反应处于界面化学反应控制，在整个还原过程中，界面反应阻力起到了决定性的作用。球团在还原过程中，界面化学反应阻力与内扩散阻力都随温度的增加而减小。在还原过程中，铁氧化物从高价到低价逐级还原，外部形成铁壳层，而内部尚有一个未反应的核心。随着反应推进，未反应核心逐渐缩小，直到完全消失，垃圾球团内部比不含垃圾球团多一些孔洞，但配入的垃圾不影响直接还原铁的质量。本研究提出的垃圾应用于直接还原铁生产技术，这一新型冶炼想法符合节能环保方向。...