新型干法中温脱硝剂的设计制备及脱硝机理

doi:10.16085/j.issn.1000-6613.2020-0820

摘要/Abstract

摘要：

针对现有选择性非催化还原（SNCR）技术脱硝效率低、操作温度高（800～1100℃）的问题，本文通过优选富含氨基的有机单体进行聚合获得高分子促进剂，并与尿素、界面剂和助剂等复配，设计了系列新型中温干法脱硝剂。研究表明，添加有机聚合物能有效提高样品的脱硝性能。通过对样品的脱硝评价结果进行比较，发现所制备的高分子促进剂不仅可以促进脱硝温度窗口向中温方向移动，而且具有良好中温脱硝促进效果，当反应温度为563～596℃时，氮氧化物的脱除率可达95.0%。同时，研究发现用壳聚糖、羟丙基甲基纤维素代替本文制备的促进剂时，亦具有脱硝促进作用，但效果不如后者。此外，本文利用FTIR、NMR、TG等系列表征技术，对制备的高分子促进剂进行分析，结合脱硝反应评价结果，尝试推导新型干法脱硝剂的反应过程机理。

关键词: 脱硝, 干法, 中温, 高分子促进剂, 烟气处理

Abstract:

The current selective non-catalytic reduction (SNCR) has the problems of high reaction temperature (800—110℃) and low efficiency. In this paper, a novel dry denitration agent for moderate temperature was designed, and it was prepared with polymer promoter, urea, interface agent and oxide additives. The polymer promoter was obtained from amino rich organic monomers through polymerization. It was found that adding the organic polymer promoted the denitration performance. Comparing of the denitration evaluation of different samples, it is found that the prepared polymer promoter possessed the best promoting performance as well as shifted the temperature window to a much lower range with the corresponding NO removal rate of 95.0% and optimal temperature range of 563—596℃. Chitosan and hydroxypropylmethylcellulose used as promoters can also improve the NO removal rate. FTIR, NMR and TG were used to analyze the polymer promoter, and the reaction mechanism of the novel dry-process denitration was deduced.

Key words: denitration, dry process, moderate temperature, polymer promoter, flue gas treatment

中图分类号:

TQ09

石君君, 原晓华, 谢吴成, 陈海军. 新型干法中温脱硝剂的设计制备及脱硝机理[J]. 化工进展, 2020, 39(9): 3835-3841.

Junjun SHI, Xiaohua YUAN, Wucheng XIE, Haijun CHEN. Preparation of a novel dry-process moderate temperature denitration agent and its denitration mechanism[J]. Chemical Industry and Engineering Progress, 2020, 39(9): 3835-3841.

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