基于典型行业的氨法烟气脱硫中硫酸铵结晶研究进展  

Research Progress of Ammonium Sulfate Crystallization in Ammonia Flue Gas Desulfurization Based on Typical Industry Characteristics

作　　者：张圆圆[1] 王文振 许小静 杨凤玲[1] ZHANG Yuanyuan;WANG Wenzhen;XU Xiaojing;YANG Fengling(Engineering Research Center of CO2 Emission Reduction and Resource Utilization-Ministry of Education of the People’s Republic of China,State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste Resources,Shanxi University,030006 Taiyuan,China;Shanxi Liulin Electric Power Company Limited,033000 Lüliang,China)

机构地区：[1]山西大学CO_(2)减排与资源化利用教育部工程研究中心,国家环境保护煤炭废弃物资源化高效利用技术重点实验室,太原030006 [2]山西柳林电力有限责任公司,山西吕梁033000

出　　处：《煤炭转化》2022年第4期92-105,共14页Coal Conversion

基　　金：国家重点研发计划项目(2020YFB0606201);山西省高等学校科技创新项目(2020L0008);襄垣县固废综合利用科技攻关项目(2018XYSDCY-02,2018XYSDYY-12)。

摘　　要：氨法烟气脱硫工艺广泛用于煤化工、钢铁、火电、有色金属和造纸等行业,脱硫副产物硫酸铵的品质直接影响企业的运行稳定和经济效益。本研究通过对煤化工、钢铁、火电、有色金属行业烟气特点的对比分析,将影响氨法烟气脱硫中硫酸铵结晶的因素归为操作条件和杂质引入两大类,其中操作条件包括吸收氧化过程中的氧化条件(催化剂、盐浓度、温度、pH和空气流量)和硫酸铵结晶过程中的结晶条件(pH、温度、搅拌速度),杂质引入分为有机杂质(油类和酚类等)和无机杂质(飞灰、Al^(3+)、Fe^(3+)和Cl^(-)等),分析了操作条件和杂质引入对硫酸铵结晶的影响机制,如过渡金属催化体系对亚硫酸铵氧化速率的提高作用,高盐浓度通过增大液膜阻力、高温通过提高氧溶解能力,影响到亚硫酸铵氧化反应动力学;pH、温度、搅拌速度均会影响硫酸铵溶液的介稳区,以致影响过饱和度,进而影响硫酸铵晶体的大小与晶形;有机杂质会附着在硫酸铵晶体表面,阻碍晶核的生成和晶体的生长,无机杂质可作为非均相核影响硫酸铵结晶,其含量将直接影响晶面生长速率,进而影响硫酸铵晶体的粒径及晶形。进一步针对氨法烟气脱硫中因操作条件控制不当或部分杂质引入导致的现场问题,提出可采取实时监控等方式,及时了解硫酸铵结晶过程中氧化率、产品晶形、有机杂质和无机杂质等所处水平,预判在当前控制条件下硫酸铵溶液的结晶趋势,及时就相关条件做出操作动态调控,实现硫酸铵结晶的过程控制和针对性操作的动态预调整。同时基于系统论观点,从科学研究层面,提出可针对行业特点,从燃料性质、热转化条件、烟气组成及性质、氨水成分、吸收氧化条件、结晶操作条件等全流程多角度系统研究硫酸铵的结晶过程,提出具有行业特色的硫酸铵结晶调控工艺;从企业管理层面,提�Ammonia flue gas desulfurization process is widely used in the coal chemical industry,iron processing,thermal power generations,non-ferrous metal and papermaking,and other industries.The quality of ammonium sulfate((NH_(4))_(2)SO_(4)),which is a byproduct of desulphurization,directly affects the stable operation and economic benefits of enterprises.Based on the comparative analysis of characteristics of flue gas in the coal chemical industry,iron processing,thermal power generations,and non-ferrous metal industry,this paper classified influencing factors on the crystallization of(NH_(4))_(2)SO_(4)in ammonia flue gas desulfurization into two categories:operating conditions and impurities.The operating conditions included oxidation conditions in the process of absorption and oxidation(catalyst,salt concentration,temperature,pH,and air flow rate)and crystallization conditions in the crystallization process of(NH_(4))_(2)SO_(4)(pH,temperature,stirring speed).The impurities were divided into organic impurities(oil,phenols,etc.)and inorganic impurities(fly ash,Al^(3+),Fe^(3+),Cl^(-),etc.).The effect of operating conditions and impurities on the crystallization of(NH_(4))_(2)SO_(4)was also analyzed.The oxidation rate of(NH_(4))_(2)SO_(4)was improved by transition metal catalysts.High salt concentrations improved the oxygen dissolving capacity by increasing liquid film resistance and high temperature,further affecting the oxidation kinetics of(NH_(4))_(2)SO_(4).The metastable zone of ammonium sulfate solution was affected by pH value,temperature,and stirring speed,which had an influence on the supersaturation of the solution as well as the crystal size and shape of(NH_(4))_(2)SO_(4).The formations of crystal nuclei and crystal growth were hindered by the adhesion of organic impurities on the surface of(NH_(4))_(2)SO_(4)crystals.The content of inorganic impurities,serving as heterogeneous nuclei,directly influenced the growth rate of the crystal plane,thereby affecting the particle size and crystal shape of(NH_(4))_(2)SO_

关 键 词：氨法烟气脱硫 行业特点 硫酸铵结晶 操作条件 杂质 

分 类 号：X789[环境科学与工程—环境工程]