The double alkali method is also called sodium calcium double alkali method [NaOH-Ca(OH)2]. The sodium base absorbs SO2 and calcium alkali regeneration. Compared with other desulfurization processes such as lime gypsum, it has the following advantages:
- The sodium-alkali absorbent has high reactivity and fast absorption rate, which can reduce the liquid-gas ratio, thereby reducing operating costs and reducing investment in pools, pumps and pipelines.
- Regeneration and sedimentation are separated outside the tower, which greatly reduces the chance of fouling inside the tower and in the pipeline.
- Sodium base can be recycled to reduce losses and operating costs.
- Gray water is easy to precipitate and separate, which can greatly reduce the investment in the pool.
- The desulfurization slag is non-toxic, has very low solubility, no secondary pollution, and can be comprehensively utilized.
- Easy to operate, the system can be stable for a long time.