【作者】 熊丽君；

【导师】 张忠诚；

【作者基本信息】 山东大学 ， 化学工艺， 2009， 硕士

【摘要】 本文研究了一种新的生物质燃气脱焦方法。该方法改变传统的除焦理念,通过脱除燃气中露点温度高于正常使用温度的部分焦油组分,降低燃气中焦油的露点温度,使其中的各组分在常温时以气态的形式存在于燃气当中,从而解决由于焦油凝结造成的问题。并在脱焦的过程中,通过使燃气的温度保持在水的露点温度之上,防止燃气中水的析出带来污染问题。新工艺方法利用两种溶剂来脱除燃气中的焦油,溶剂1冷却收集焦油中的重组分,溶剂2吸收焦油中的轻组分。溶剂1不溶解焦油,起到的是冷却作用,通过静置分离出其中的焦油后可反复使用;而溶剂2则对焦油具有较强的吸收作用,需要通过空气吹脱作用,分离出其中的焦油组分后被重新用作吸收剂。因此,该方法中的溶剂可循环再生使用,能够节约资源降低成本。新工艺在塔高为6m,直径为0.5m,填料高度为1.5m的填料塔上进行中试实验,燃气流速为1000m~3/h,溶剂流速为8 m~3/h。经处理后的燃气焦油含量可降至原来的1%以下,表明该工艺能够有效地脱除生物质燃气中的焦油组分,解决由焦油的凝结产生的问题。本文还利用ASPEN PLUS化工模拟软件对工艺过程进行模拟计算。以RK-SOAVE物性方法作为计算方法,RadFrac模块作为塔的计算模块,通过设计计算过程的模型和方法,分析了收集塔气体出口温度随溶剂1的进口温度及流量之间的变化关系,以及焦油脱除率随吸收塔溶剂2的进口流量和吹脱塔空气进口流量之间的变化关系。由模拟计算的结果得到,在轻组分的吸收和溶剂的吹脱再生过程中,随着吸收溶剂流量的增大,焦油的脱除率并不会不断提高,而是在某一个流量值时达到最大;随着吹脱所用空气流量的增大,当溶剂中焦油的含量降低至一定程度时,继续增大空气量将对吹脱效果的影响不大。这些结论为实际过程的工艺优化提供参考依据。更多还原

【Abstract】 Here studied a new tar removal technology. This approach solved fouling related problems by reducing the dew point of tar to levels below the lowest expected temperature and avoided waste water condensation by remaining the exit temperature of tar removal process above the dew point of the water steam in the syngas.New technology used two scrubbing liquids to remove tar. Liquid 1 acted as the medium to collect heavy tars, and the light tars were absorbed by Liquid 2. Heavy tars did not dissolve in Liquid 1, which is regenerated by separating. Liquid 2 with the dissolved tars is regenerated by air stripping. The circulation of scrubbing liquid in this technology reduced investment and saved resource.Pilot plant test of new technology was on pack columns. The height of them is 6m, the diameter is 0.5m, and the pack height is 1.5m. Flow rate of syngas is 1000m~3/h, which of scrubbing liquid is 8m~3/h. The result showed that tar removal rate could reach to 99%. It was concluded that this new technology could remove tar from biomass syngas successfully.Based on ASPEN PLUS software, the simulations of the tar removal technology were performed in this study with RK-SOAVE property method and RadFrac model as columns. By designing calculation methods, the factors which affected the tar removal rate were analyzed. Results of absorbing-stripping process were obtained such as that when flow rate of scrubbing liquid increased, tar removal rate would not increase continually but have a peak value instead; when flow rate of stripping air increased, tar removal rate increased and reached a steady degree.更多还原