3.1本脱硫塔烟气处理工艺根据当前环保要求，脱硫工艺选择为双碱法（并满足单碱法工况要求）。
3.1 According to the current environmental protection requirements, the desulfurization process of this desulfurization tower is double alkali process (and meets the requirements of single alkali process).
3.2双碱法烟气脱硫技术
3.2 Dual-alkali Flue Gas Desulfurization Technology
双碱法烟气脱硫工艺是为了克服石灰石/石灰—石膏法容易结垢的缺点而逐步发展起来的。它先用碱金属盐类如NaOH、Na2CO3、NaHCO3、Na2SO3等的水溶液吸收SO2，然后在另一反应器中用石灰或石灰石将吸收SO2后的溶液再生，再生后的吸收液循环使用，而SO2最终以石膏的形式析出。
Dual-alkali flue gas desulfurization process is developed to overcome the shortcomings of limestone/lime-gypsum method which is easy to scale. It first absorbs SO2 with aqueous solutions of alkali metal salts such as NaOH, Na2CO3, NaHCO 3 and Na2SO3, then regenerates SO2 with lime or limestone in another reactor. The regenerated absorbent is recycled, and SO2 eventually precipitates in the form of gypsum.
以NaOH为例，其主要工艺过程是，清水池一次性加入NaOH溶剂制成脱硫液，用泵打入吸收塔进行脱硫，从脱硫塔排出的循环浆液流入再生池、沉淀池，然后上清液再回到清水池。灰渣及石膏等脱硫产物经沉淀后定期清除，可作为建材回收利用。再生池内投加熟化好的Ca(OH)2溶液与循环浆液进行反应，置换出的NaOH溶解在循环水中，同时生成难溶的亚硫酸钙、硫酸钙和碳酸钙等，可通过沉淀清除。
Taking NaOH as an example, the main process is to add NaOH solvent to the clean water tank at one time to make desulfurization liquid, and pump it into the absorption tower for desulfurization. The circulating slurry discharged from the desulfurization tower flows into the regeneration tank and sedimentation tank, and then the supernatant returns to the clean water tank. The desulfurization products such as slag and gypsum are regularly removed after precipitation, and can be recycled as building materials. The regeneration tank is reacted with circulating slurry by adding matured Ca (OH) 2 solution. The replaced NaOH is dissolved in circulating water, and insoluble calcium sulfite, calcium sulfate and calcium carbonate are produced simultaneously, which can be removed by precipitation.