赤泥微波干法固定碱及其机理分析

赤泥是通过拜耳法精炼铝土矿产生的一种强碱性工业固体废物。以遵义某拜耳法氧化铝厂排出的赤泥为样品，开发出微波干法快速固碱技术，并就其干法固碱原理进行研究。研究表明，赤泥经过微波干法固碱，功率为392 W,微波频率2 450 MHz,波长122 mm,仅需要40 min,其pH可以从10.88降低至8.11,固碱过程不产生二次污染物。通过XRD和SEM分析发现，赤泥成分、外貌颜色、表观形态及粒径都存在变化。

Alkali Fixation of Red Mud by Microwave Dry Method and Its Mechanism Analysis

Red mud is a strongly alkaline industrial solid waste produced by the Bayer process bauxite refining. The red mud provided by a Bayer process alumina plant in Zunyi was used as a sample to develop a microwave fast dry alkali fixation process, and the principle was studied. The results show that pH value of red mud can be reduced from 10.88 to 8.11 in only 40 minutes after microwave dry process under the conditions including microwave power of 392 W, microwave frequency of 2 450 MHz, and wavelength of 122 mm. The alkali fixation process does not produce secondary pollutants. The analysis results of XRD and SEM show that composition, appearance color, apparent morphology and particle size of red mud are all change.