煤气化废水成浆特性及添加剂的适配性

Slurryability of coal gasification wastewater and adaptation of additives

利用煤气化过程中洗气工艺段产生的有机废水(简称"洗气水")、实验室中的去离子水分别与神华煤制备水煤浆,并进行了成浆性、流变性、稳定性以及添加剂适配性的实验。研究结果表明,洗气水水煤浆的定黏浓度能达到61%以上,比去离子水水煤浆高1%~2%,假塑性特征也更加明显;比较不同添加剂的成浆效果,发现亚甲基双萘磺酸钠和萘系添加剂的效果较好;水煤浆的稳定性与添加剂的结构有关,木质素磺酸钠由于能形成稳定的络合结构因此浆体具有较好的稳定性;与去离子水水煤浆相比,洗气水水煤浆的触变性和稳定性有所降低。利用洗气水制备水煤浆,不仅实现了废水的资源化、无害化利用,而且能提高浆体的成浆浓度,具有较好的工业应用前景。

This paper carried out the experiment about slurryability, rheological properties, stability, and additive adaption of coal water slurry, which was made by organic wastewater from the gas washing process of coal gasification（gas washing water for short）, deionized water and Shenhua coal. The results indicated that the solid concentration of coal-gas washing water-slurry can reach more than 61%, which was 1%~2% higher than coal water slurry and pseudoplastic was more obvious. By comparing the effect of different additives, it was found that the dispersing agents NNO and FDN were better. The stability of coal water slurry was related to the structure of additives and ligninesulfonic acid sodium salt（LS） showed a better result because of the formation of steady complex structure. Comparing with coal water slurry, the thixotropy and stability of coal-gas washing water-slurry were slightly lower. The application of coal gasification wastewater for production of coal water slurry not only realized the resource and harmless utilization of wastewater, but also improved the slurry concentration, which was with a good industrial application prospect.