中文题名 生物质类吸附材料在脱硫废水除氟中的应用
英文题名 Application of Biomass Adsorbents in Deflorination Desulfurization Wastewater
作者:曹政a、闫征楚b、周德亚b、李晨*b、刘展b、余桂宁b、陆晟星b、姜晴晴b
作者单位:1.包头股份动供总厂 2.中电创新环境
作者地址:江苏省 无锡市 新吴区具区路88号 中电创新环境有限公司 13722837721
摘要
木质素是生物质的重要做成部分。其热解的液体产品生物油和固体产品生物炭是木质素热解的主要增值产品。由于应用范围窄、质量低,采用热解法生产生物油不能带来足够的经济效益,木质素基的生物炭其应用条件和范围需要进一步明确。本文研究了两种提高木质素生物制品质量的方法,并针对生物炭基吸附材料在脱硫废水处理上的应用展开了中试规模的研究。
本研究引入了化学活化(热解)来取代直接热解。与生物炭相比,木质素化学活化产物木质素活性炭具有更好的经济价值。在最佳活化条件下,生成的木质素活性炭表面积约为1117 m2/g,收率可达50%左右。与商业活性炭相比,木质素活性炭具有相似的碘值、亚甲基蓝值、BET 表面积、更好的产率。使用ZnCl2活性炭法被证明是利用木质素生物质残渣的最佳方法之一。
煤燃烧后产生大量的含二氧化硫烟气,用碱性物质吸收后,用水冲洗产生大量的高COD、高盐分、高氨氮、高氟化物的脱硫废水。采用木质素吸附材料对该种废水进行处理,连续运行7天后发现, 其对COD和氨氮的去除效果可达50%,对氟化物的去除效果可以达到约90%。
关键词:生物质;木质素;热解;活性炭;除氟;脱硫废水
Abstract
Lignin is an important part of biomass. Bio-oil and biochar are the main value-added products after lignin pyrolysis. Due to the narrow application range and low quality, the use of pyrolysis to produce bio-oil cannot bring sufficient economic benefits. The application conditions and scope of lignin-based biochar need to be further clarified. This report has studied two methods to improve the quality of lignin bio-products, and carried out a pilot scale study on the application of biochar-based adsorption in the treatment of desulfurization wastewater.
The research in this report introduced chemical activation (pyrolysis) to replace direct pyrolysis. Compared with biochar, lignin-based activated carbon, a chemical activation product of lignin, has better economic value. Under the optimal activation conditions, the surface area of the produced activated carbon is about 1117 m2/g, and the yield can reach about 50%. Compared with commercial activated carbon, lignin activated carbon has similar iodine value, methylene blue value, BET surface area, and better yield. The application of ZnCl2 activation method has been proved to be one of the best methods to utilize lignin biomass residues.
After coal is burned, a large amount of sulfur dioxide-containing flue gas is produced. After being absorbed by an alkaline substance, it is washed with water to generate a large amount of desulfurization wastewater with high COD, high salinity, high ammonia nitrogen, and high fluoride. The lignin adsorbent is used to treat this kind of wastewater. After 7 days of continuous operation, it is found that the removal effect of COD and ammonia nitrogen can reach 50%, and the removal effect of fluoride can reach about 90%.
Key words: biomass; lignin; pyrolysis; activated carbon; furfural; acetone; Deflorination; desulfurization wastewater
木质素是一种宝贵的能源资源,与纤维素和半纤维素一起是组成木材的三大主要成分。木质素是第二大有机原料来源地[1],约占大多数生物质的 4-35 wt%、硬木的 16-25 wt% 和软木的 23-35 wt% [2]。作为最丰富的天然芳香聚合物[3],木质素具有高度支化的三维酚结构(图1-1),包括三个主要的苯丙烷单元,即对香豆素、松柏基和芥子基。软木木质素含有较少的芥子醇基单元,主要由木酰基结构组成,而硬木木质素含有木酰基丁香基结构。