A comparison of acid treatment in the dewatering of Chinese and Australian lignites by mechanical thermal expression at high temperatures
A comparison of acid treatment in the dewatering of Chinese and Australian lignites by mechanical thermal expression at high temperatures
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中国与澳大利亚褐煤高温机械热力脱水酸处理比较
DOI：
10.1016/j.fuproc.2016.01.010
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发表时间：
2016-04
影响因子：
7.5
通讯作者：
Alan Chaffee
中科院分区：
文献类型：
--
作者：
Qiongqiong He;Hasina Yeasmin;Zhenyong Miao;Keji Wan;Shaomeng Huang;Andrew Hoadley;Ying Qi;Alan Chaffee
机械热压榨法是一种有效的高水分褐煤脱水方法。然而，废水的高总有机碳（TOC）在排放到环境中之前需要进一步的化学处理。在这项工作中，固体产品和废水的特性的变化，当硫酸被用作MTE过程的一部分。两个褐煤进行了测试：来自澳大利亚的Loy Yang（LY）和来自中国的ShengLi（SL）。分析了固体产物和废水的特性。挤压温度（200 °C和240 °C）对LY的水分含量降低的影响是明显的，但对SL的影响仅是边缘的。在任一种情况下，固体产物的最终水分含量不受添加硫酸的影响，但压汞法侵入分析显示LY的孔体积减小更大。据推测，酸处理抑制溶解的酚类和羧基的LY的情况下。对于具有不同显微组分结构的SL，由于当不使用酸时溶解的酚类化合物的浓度低得多，因此酸添加的影响不太显著。看来，酸的加入抑制了褐煤显微组分中有机物的解离，也降低了溶解速率，导致废水中TOC较低。因此，在MTE期间加入硫酸后，废水变得更容易处理。MTE工艺还可以去除溶解的盐和有机结合的矿物质，这有助于减少褐煤中的污垢成分，并可能降低燃烧后烟气中的PM10浓度。
Mechanical thermal expression (MTE) is an effective and efficient method of dewatering high moisture content lignite. However the high total organic carbon (TOC) of the wastewater requires further chemical treatment, before discharge to the environment. In this work, changes in the characteristics of the solid products and the wastewater are reported, when sulphuric acid is used as part of the MTE process.Two lignites were tested: Loy Yang (LY) from Australia and ShengLi (SL) from China. The characteristics of the solid products and wastewater were analysed for both. The effect of expression temperature (200 °C and 240 °C) on moisture content reduction is evident for LY, but it is only marginal for SL. The final moisture content of the solid product in either case is not impacted by the addition of sulphuric acid, but the mercury porosimetry intrusion analysis showed a greater reduction in pore volume for LY. It is postulated that acid treatment suppresses the solubilization of phenols and carboxylic groups in the case of LY. For SL with a different maceral structure, as the concentration of the solubilized phenolic compounds is much lower when no acid is used, the impact of acid addition is much less significant. It appears that the addition of acid inhibits the dissociation of organics from the lignite macerals and also reduces the rate of dissolution, leading to lower TOC in the wastewater. Thus, the wastewater becomes easier to treat after sulphuric acid addition during MTE. The MTE process also removes dissolved salt and organically-bound minerals which aids in reducing the fouling components in the lignite and possibly the PM10concentrations in the flue gas following combustion.
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DOI：
10.1016/j.ijmst.2013.12.023
发表时间：
2014
影响因子：
11.8
作者：
Chunmei Qian;Min Zhou;Jian X. Wei;Puhai Ye;Xuliang Yang
通讯作者：
Chunmei Qian;Min Zhou;Jian X. Wei;Puhai Ye;Xuliang Yang
DOI：
--
发表时间：
2004
期刊：
--
影响因子：
--
作者：
Y. Qi
通讯作者：
Y. Qi
DOI：
10.1021/bk-1984-0264.ch008
发表时间：
1984
期刊：
--
影响因子：
--
作者：
N. Mallya;R. Zingaro
通讯作者：
N. Mallya;R. Zingaro
DOI：
10.1016/j.colsurfa.2013.03.030
发表时间：
2013-06-20
影响因子：
5.2
作者：
Kloster, Nanci;Brigante, Maximiliano;Avena, Marcelo
通讯作者：
Avena, Marcelo
影响因子：
4.2
作者：
Sui Boon Liaw;Hongwei Wu
通讯作者：
Sui Boon Liaw;Hongwei Wu