【作者】 宋婷；

【导师】 李光哲；

【作者基本信息】 沈阳师范大学 ， 分析化学， 2012， 硕士

【摘要】 SO₂的大量排放及其所产生的酸雨已成为重大的环境问题之一。化石燃料尤其是煤炭的燃烧是SO₂大量排放的主要原因。因此燃煤烟气中SO₂减排技术对其污染的控制起到重要作用。SO₂脱除技术众多，为适用于燃煤电厂中SO₂、CO₂的联合脱除，本文采用NH₄HCO₃作为吸收剂进行模拟烟气中SO₂的吸收实验。本文研究的主要内容包括吸收过程的理论探讨及实验研究。理论探讨以双膜吸收理论为基础，对SO₂与NH₄HCO₃溶液反应的反应机理及吸收传质过程进行分析，探讨NH₄HCO₃溶液脱硫的化学吸收过程。认为NH₄HCO₃与SO₂的反应为瞬间反应，SO₂吸收过程受双膜传质控制。吸收速率主要受气膜传质控制，但吸收反应接近平衡状态时，吸收速率主要受化学反应控制。在NH₄HCO₃溶液吸收SO₂实验研究中，分别采用鼓泡式反应器和喷淋式反应器进行NH₄HCO₃脱除SO₂的吸收性能评价。在鼓泡式吸收实验，考察比较NH₄HCO₃溶液、氨水、Na₂CO₃溶液、NaOH溶液的脱硫性能，以及NH₄HCO₃溶液浓度、SO₂浓度、气体流速对反应的影响。结果验证NH₄HCO₃溶液与其他吸收剂相比同样具有良好的脱硫效果，适用于燃煤烟气中SO₂的脱除。碳酸氢铵溶液浓度越高，SO₂脱除率越高，SO₂吸收量越高，吸收速率越快；SO₂浓度越低时，SO₂脱除率越低，吸收速率越快，SO₂吸收量相差不大；气体流速越快时，SO₂脱除率越低，吸收速率越快，SO₂吸收量相差不大。在喷淋式吸收实验，以NH₄HCO₃溶液为吸收液，在室温条件下，考察了吸收液浓度、氮硫比、气体流速对脱硫效率和反应速度的影响。结果表明NH₄HCO₃溶液浓度越高，SO₂脱除率越高，SO₂吸收量越高，吸收速率越快；SO₂浓度越低时，SO₂脱除率越低，吸收速率越慢，SO₂吸收量越低；气体流速越快时，SO₂脱除率越低，吸收速率越快，SO₂吸收量越高。相应本实验的吸收装置，氮硫比为2比1，气体流速为8L/min，吸收液浓度为8%可达到较高的脱除率和反应速率。可实现燃煤烟气中SO₂的脱除。通过上述吸收机理的探讨和采用鼓泡式反应器和喷淋式反应器的实验研究，证明NH₄HCO₃溶液具有很好的脱硫效果，可以应用于燃煤烟气SO₂脱除，为燃煤烟气的联合脱硫脱碳提供了一种可行方法。更多还原

【Abstract】 Sulfur dioxide emission and the resulting acid rain has become one of the majorenvironmental issues. The burning of fossil fuels, especially coal combustion is largenumber of emission of the main sulfur dioxide. Therefore, the desulfurationtechnologies of flue gas play an important role in the control of sulfur dioxidepollution. Sulfur dioxide removal technology vertical, in order to apply to combinedremoval of sulfur dioxide and carbon dioxid in coal-fired power plants, I usingNH4HCO3as an absorbent for SO₂ absorption in the simulated flue gas experiments.The main contents of this paper，the theoretical discussion and experimentalstudy of the absorption process. In the theoretical discussion, Based on the two-filmmass transfer theory，analysis of the absorption of SO₂ in the water mass transferprocess. And analysis of the reaction process of SO₂ with Liquor of NH₄HCO₃.Studies have shown that,NH₄HCO₃ and SO₂ reaction of the transient response, SO₂absorption process by the two-film mass transfer control. The absorption rate wasmainly bullied mass transfer control, but the absorption of the reaction close toequilibrium, the absorption rate is mainly affected by the chemical reaction control.NH₄HCO₃ solution is absorbed in the experimental study of SO₂, I use thebubbling reactor and spray reactor NH₄HCO₃ for SO₂ removal absorption propertieswere evaluated. Absorption experiments in the Bubble. First, study NH₄HCO₃solution, Na2CO3solution, NaOH solution, ammonia desulfurization performance.Studies have shown that,NH₄HCO₃ solution compared with other absorbers also hasgood desulfurization effect, applicable to coal-fired flue gas SO₂ removal.StudyNH4HCO3 solution concentration, SO₂ concentration, gas flow rate influence on thereaction. Studies have shown that.Higher the concentration of ammonium bicarbonatesolution, the higher the SO₂ removal rate of SO₂ absorption is higher, the faster theabsorption rate; the lower SO₂ concentration, SO₂removal rate is lower, the faster theabsorption rate of SO₂ uptake less; the faster of the gas flow rate, SO₂ removal rate,the lower, the faster the absorption rate of SO₂ uptake or less.Using the venturi spray gun spray in the empty tower, the absorption solution is NH₄HCO₃solution, at room temperature, the effects of absorption concentration,nitrogen and sulfur retention time on the desulfurization efficiency and speed ofresponse. Provide the experimental basis for this method to be applied in industry. Theresults showed that：Choose N/S ratio of 2:1, the gas flow rate of 6L/min absorptionconcentration of 6% to achieve a higher removal rate and reaction rate.SO₂removalfrom flue gas.By the absorption mechanism of bubble column reactor and spray reactorexperimental study to prove that NH₄HCO₃ solution has the effect of desulfurizationcan be applied to coal-fired flue gas SO₂ removal for coal-fired flue gasthe jointdesulfurization and decarbonization provides a viable method.更多还原