Perfect removal of SOx, NOx, NH3 and dioxin over activated carbon fiber

活性炭纤维完美去除 SOx、NOx、NH3 和二恶英

基本信息

批准号：
11218208
负责人：
MOCHIDA Isao
金额：
$ 20.35万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2002
项目状态：
已结题

项目摘要

A flue gas treatment which consisted of switching two steps : removal of S0_2 and regeneration of adsorption ability, using a pitch based activated carbon fiber of very large surface area (ACF), was proposed to allow the continuous removal of S0_2 in flue gas with limited humidity at 50-70℃. Removal of S0_2 at 60-70℃ and regeneration at 30℃ with humid air without S0_2 were found successful to design a switching procedure. Higher temperature of regeneration required more time, although a small difference of two temperatures may be easy for control. The second procedure which removed S0_2 successively at two different temperatures was found also possible although the period of removal at a higher temperature was rather short. This procedure relies on the fact that the amount of adsorbed H_2S0_4 on ACF under stationary conditions was smaller at a lower temperature when sufficient amount of ACF was loaded. In both cases, the regeneration to elute out ad. H_2S0_4 over ACF is the rate determining. It is found by TPD that the regeneration at 30℃ and 70℃ eluted preferentially two H_2S0_4 species over the ACF surface which evolved at lower and higher temperatures, respectively. Adsorbed H_2S0_4 located in the pore which is easily reduced to evolve at a lower temperature in TPD procedure is eluted first at 30℃ since H_20 vapor can get into the pore at the temperature. In contrast, adsorbed H_2S0_4 located on the outer surface of ACF was preferably eluted out at 70℃. Such H_2S0_4 is away from the reactive ACF surface to be reduced to evolve at a higher temperature in TPD.

提出了一种烟气处理方法，采用大表面积（ACF）的沥青基活性炭纤维，从去除S0_2和吸附能力再生两个步骤开始切换，以在有限的条件下连续去除烟气中的S0_2。发现在 50-70℃ 下去除 S0_2 并在 30℃ 下用不含 S0_2 的湿空气再生，成功地设计了更高的温度。再生需要更多的时间，尽管两个温度的微小差异可能容易控制，但发现在两个不同温度下连续去除S0_2的第二个程序也是可能的，尽管在较高温度下去除的时间相当短。事实上，当加载足够量的 ACF 时，在固定条件下 ACF 上吸附的 H_2S0_4 量较小。通过TPD测定发现，30℃和70℃的再生比ACF表面优先洗脱出两种H_2S0_4，它们分别在较低温度和较高温度下析出，吸附在孔中的H_2S0_4在较高温度下容易被还原。 TPD程序中的温度较低，在30℃时首先洗脱，因为H_20蒸气可以在该温度下进入孔内，相反，被吸附。位于ACF外表面的H_2S0_4优选在70℃下洗脱出来，这样H_2S0_4远离反应性ACF表面，在TPD中在较高温度下被还原析出。