Wet oxidation-absorption is a promising process for flue gas desulfurization and denitration due to its simple system and high removal efficiency. In comparison to the ordinary bubbles, micro-nano bubbles have some special properties such as spontaneous generation of hydroxyl free radicals and self-pressurized solution. Sodium humate (HA-Na), which is a cheap, easily accessible and recyclable reagent, can react with ${\mathrm{H}}^{+}$ to produce humic acid sediment so that it may promote the solution of NO₂ and SO₂ in the water. In this study, a new wet recycling micro-nano bubble oxidation-absorption process based on HA-Na was developed for the simultaneous removal of NO and SO₂. A micro-nano bubble generator (MNBG) was utilized to generate the micro-nano bubble oxidation-absorption system (MNBOS) from HA-Na aqueous solution and the mixed gases, composed of N₂, NO, SO₂ and/or other gases including O₂ and CO₂. The MNBOS was recycled continuously from the MNBG to the reactor. The critical operation parameters, including operation time, initial pH and temperature of the absorbent, HA-Na concentration, NO concentration, SO₂ concentration, presence of O₂ and/or CO₂, were investigated to explore the simultaneous removal of NO and SO₂ with the MNBOS. The results showed that hydroxyl free radicals generated by micro-nano bubbles played a critical role in the removal of NO and HA-Na promoted the removal of NO. All the investigated parameters affected NO removal. Only initial pH and temperature of the solution and concentrations of NO and SO₂ affected SO₂ removal, whereas the presence of O₂ and CO₂ or HA-Na concentration had no significant effect on SO₂ removal. This new process could achieve high removal efficiency which was respectively above 91.1% for NO and 99.7% for SO₂ under the conditions of 0.5 g/L HA-Na, initial solution pH 7.47, initial solution temperature 298 K, 1250 ppm NO and 1650 ppm SO₂. Moreover, according to the analysis of FTIR and XPS, the removal products were mainly HA, sulfate and nitrate, which are the components of fertilizer and can be recycled as compound fertilizer which has higher activity compared with the traditional HA fertilizer because HA from this system is subjected to oxygenolysis by nitric acid and sulfuric acid in solution.

湿式氧化吸收由于其简单的系统和较高的去除效率而成为烟气脱硫和脱硝的有前途的方法。与普通气泡相比，微纳米气泡具有一些特殊的特性，例如自发生成羟基自由基和自加压溶液。腐植酸钠（HA-Na）是一种廉价，易于获取且可回收的试剂，可以与${\mathrm{H}}^{+}$产生腐殖酸沉淀物，从而促进水中的NO ₂和SO ₂溶解。在这项研究中，开发了一种新的基于HA-Na的湿循环微纳气泡氧化吸附工艺，用于同时去除NO和SO ₂。利用微纳气泡发生器（MNBG）从HA-Na水溶液和由N ₂，NO，SO ₂和/或其他气体组成的混合气体中生成微纳气泡氧化吸收系统（MNBOS）包括O ₂和CO ₂。MNBOS从MNBG连续循环到反应器中。研究了关键操作参数，包括操作时间，吸收剂的初始pH和温度，HA-Na浓度，NO浓度，SO ₂浓度，O ₂和/或CO _2的存在，以探索同时去除NO和SO的方法。₂与MNBOS。结果表明，微纳米气泡产生的羟基自由基在NO的去除中起关键作用，而HA-Na促进NO的去除。所有研究的参数均影响NO的去除。仅溶液的初始pH和温度以及NO和SO _2的浓度会影响SO _2的去除，而O的存在₂和CO ₂或HA-Na浓度对SO _2的去除没有显着影响。在0.5 g / L HA-Na，初始溶液pH 7.47，初始溶液温度298 K，1250 ppm NO和1650的条件下，该新工艺可以获得较高的去除效率，分别对NO的去除效率为91.1％，对SO _2的去除效率为99.7％。ppm SO ₂。此外，根据FTIR和XPS的分析，去除产物主要是HA，硫酸盐和硝酸盐，它们是肥料的组成部分，与传统的HA肥料相比，具有较高的活性，因此可以作为复合肥料进行回收，因为该系统中的HA在溶液中被硝酸和硫酸氧化分解。