煤液化残渣的污染特性和焚烧特征研究

发布时间：2018-05-19 22:24

  本文选题：煤液化残渣 + 特性　； 参考：《湖南农业大学》2015年硕士论文

【摘要】：我国的煤炭资源丰富,是主要的化工和能源原料。煤液化技术作为一种洁净煤技术,是一种清洁、高效、经济型的煤化工技术,可以有效利用我国的煤资源,成为新型煤化工技术的研究热点。本文全面系统地分析了神华煤液化残渣的来源组成、腐蚀性、反应性、易燃性、浸出毒性、毒性物质含量等危险特性,为煤液化残渣的加工利用做基础性的准备工作。通过实验笔者发现液化渣不具有腐蚀性、反应性、易燃性和浸出毒性。主要的污染特性为毒性物质含量。通过对原料煤,以及另一种煤化工产物-煤焦油进行实验与液化渣进行对比以及煤与液化渣掺烧工况的试验分析煤液化残渣作为焚烧燃料的可行性。采用热重分析仪分析了液化渣、煤、煤焦油和煤与液化渣掺烧物料的燃烧特性,并通过管式炉模拟试验,研究不同温度下掺烧烟气中苯系物和多环芳烃的排放特征。结果表明：煤、液化渣和煤焦油燃烧特性存在较大差异,液化渣主要燃烧过程所发生的温度区间为560～820℃,明显高于煤和煤焦油的主要燃烧温度区间。煤与液化渣之间燃烧特性差异导致2种物料在掺烧过程中相互影响；液化渣在700℃燃烧时苯系物排放量达到最大,为132.2mg/kg,多环芳烃排放量最小,为11.30mg/kg。由于2种物料燃烧过程的相互影响,500℃下的掺烧苯系物排放量为23.5mg/kg,远小于理论值,≥1700℃条件下掺烧苯系物排放量为172.6mg/kg,远大于理论值。多环芳烃掺烧排放量都远远大于理论值。700℃和1200℃时排放量较小,分别为138.7mg/kg、157.Omg/kg,其中大部分为2-3环多环芳烃。由此得出结论：液化渣无论是单独焚烧还是掺烧情况下,低温条件下焚烧烟气中苯系物和多环芳烃排放量远远大于高温(≥850℃)条件下,因此液化渣的焚烧处置或燃料化利用应选择高温炉型。同时,我们对比了工厂掺烧试烧过程,系统采集了各节点排放烟气和炉膛底渣,测定了底渣,烟气中各污染物的含量,研究了不同工况下污染物排放的变化。液化渣在CFB锅炉中掺烧,对多环芳烃、UP-POPs和重金属的排放基本没有影响,但是会造成二氧化硫、烟尘、总烃、挥发性卤代烃和苯系物排放的增加。Texaco(德士古)气化炉掺烧15%液化渣,对各类烟气(尾气)、和固体废物中特征有机污染物的影响较小,表明由于气化炉温度较高,有机物焚毁较为彻底,有机污染物排放的环境风险较小。
[Abstract]:China's coal resources are rich, is the main chemical and energy raw materials. As a clean coal technology, coal liquefaction technology is a kind of clean, efficient and economical coal chemical technology, which can effectively utilize the coal resources in China and become the research hotspot of new coal chemical technology. In this paper, the source composition, corrosivity, reactivity, flammability, leaching toxicity and toxic substance content of the coal liquefaction residue of Shenhua are analyzed systematically and the basic preparation work for the processing and utilization of the coal liquefaction residue is made. The author found that the liquefaction slag is not corrosive, reactive, flammable and leaching toxicity. The main pollution characteristic is the content of toxic substances. The feasibility of coal liquefaction residue as incineration fuel was analyzed by comparison of raw coal, coal tar, another coal chemical product, and liquefaction slag, as well as the mixed burning condition of coal and liquefaction slag. The combustion characteristics of liquefied slag, coal tar and coal mixed with liquefied slag were analyzed by thermogravimetric analysis. The emission characteristics of benzene series and polycyclic aromatic hydrocarbons (PAHs) in flue gas at different temperatures were studied by tube furnace simulation test. The results show that the combustion characteristics of coal, liquefied slag and coal tar are quite different. The temperature range of the main combustion process of liquefied slag is 560,820 鈩，

本文编号：1911951