Simulation of the operation of an industrial wet flue gas desulfurization system

In this work the simulation of a wet flue gas desulfurization (FGD) unit with spray tower of a power plant is presented, aiming at an efficient follow-up and the optimization of the FGD system operation. The dynamic model developed to simulate the performance of the system has been validated with operation data collected over a long period of time. All the partaking physical and chemical processes like the limestone dissolution, the crystallization of calcium sulfite and gypsum and the oxidation of sulfite ions have been taken into account for the development of the simulation model while the gas absorption by the liquid droplets was based on the two-film theory. The effect of the mean diameter of the slurry droplets on the performance of the system was examined, as it was used as an index factor of the normal operation of the system. The operation limits of the system were investigated on the basis of the model developed. It is concluded that the model is capable of simulating the system for significantly different SO₂ loads and that the absorption rate of SO₂ is strongly affected by the liquid dispersion in the tower.     

石灰石-石膏湿法烟气脱硫技术

介绍了石灰石-石膏湿法烟气脱硫技术的原理、工艺流程。石灰石-石膏湿法烟气脱硫技术具有脱硫效率高、技术成熟、单塔处理烟气量大、适用于各种煤种的烟气脱硫、吸收剂（石灰石）资源丰富,价廉易得、脱硫副产物（石膏）便于综合利用,经济效益显著等特点。     

Experimental study of wet flue gas desulphurization with a novel type PCF device

Scrubbers are being widely used to remove the dust, sulphur dioxide and other harmful gases from coal-fired boilers. In this paper, a novel ‘wet-type’ desulphurization absorber, the PCF device (Chinese LOGO), was developed and studied through an experimental method. The mixture of air and SO₂ was used as simulated flue gas and CaCO₃-in-water suspension was used as absorbent. The results show that the PCF device has a good overall performance for FGD. Under moderate conditions employed, the content of SO₂ in outlet flue gas can achieve a level much lower than that permitted, while the pressure drop is very small due to co-flows in preliminarily treating chamber and no venturi structure in inlet tube. Guide plates and self-excitation chamber can improve the SO₂ removal efficiency by intensifying the mass-transfer and second purification. Some feasible process parameters are as follows: slurry pH value = 5.6-6.0, liquid-gas ratio = 8.7-10.4 L/m³, superficial gas velocity in inner cylinder = 3.5-4.5 m/s, and addition of Cl⁻ (in the form of CaCl₂) to the slurry (25 g/L) decreased the degree of SO₂ removal about 13.12%.     

燃煤电厂烟气脱硫技术研究进展

综述了近年来国内外几种主要的烟气脱硫技术,介绍了几种常用工艺的原理、技术特点,提出了发展烟气脱硫技术存在的关键问题及其研究方向。     

一种烟气脱硫絮凝剂的改进方案与效果评价

烟气脱硫废水温度高、颗粒物重,烟气脱硫适用絮凝剂很少,本文改进了聚丙烯酰胺的常用浓度,大大提高了絮凝效果,降低了脱硫废水的吨处理费,为烟气脱硫装置提供了新的絮凝方式。     

伊泰锅炉循环流化床烟气脱硫技术研究

为提高烟气脱硫效率,在分析循环流化床脱硫工艺的基础上,根据煤质分析,选取了系统的烟气设计参数和脱硫剂参数并对脱硫效率进行分析。结果表明,循环流化床烟气脱硫技术与炉内喷钙法相结合可以达到90%的脱硫效率,SO2的排放浓度小于200 mg/m3,可以满足《锅炉大气污染物排放标准》的相关要求。与湿法脱硫技术相比,循环流化床烟气脱硫技术具有设备紧凑,投资少,占地小,特别适用于现有机组的改造工程,脱硫剂利用效率高,脱硫产物为干灰,不会产生二次污染等优点。但循环流化床烟气脱硫技术也存在着脱硫效率较湿法脱硫技术偏低,对锅炉负荷的变化适应性差,运行控制要求较高等不足。     

活性炭在烟气脱硫中的应用

综述了应用活性炭材料脱硫的三种不同方法,同时介绍了活性炭材料表面结构,含氧官能团,含氮官能团,表面负载金属氧化物对活性炭材料脱硫活性的影响。     

A model for performance optimization of wet flue gas desulfurization systems of power plants

In this paper, a model of limestone/gypsum wet flue gas desulfurization (WFGD) system was developed based on unsteady theory. The models of processes of absorption section and oxidation section were developed and incorporated into the WFGD integral model. The sub-model of motion of slurry drops, absorption of SO₂, dissolution of limestone and crystallization of gypsum were included in the model of absorption section, while the model of oxidation section was developed by the population balance theory. The calculation results of the desulfurization system for 300 MW utility in China by this model was compared to that of corresponding measured results. The simulation results agreed with the measurement results very well. The operation mode of boilers of power plant in China is different to that of other countries since variable coal property and unstable loads of boilers. The differences of operation mode lead to the variation of process parameters of WFGD system. The influences of liquid-to-gas ratio, SO₂ concentration of inlet flue gas, and combination mode of different spray levels to the desulfurization efficiency were analyzed. Based on the analysis, some advices of performance optimization of flue gas desulfurization systems in China were suggested.     

A jet mixing study in two phase gas-liquid systems

All studies concerned with jet mixing have been focused on liquid phase systems and no studies have been found on jet mixing for gas-liquid two phase systems. In the present study the use of jet fluid as a mixer in gas-liquid systems was proposed. Further by installing an experimental setup, the mixing behavior of liquid phase was studied. Gas flow and jet flow are injected to the mixing vessel countercurrently. In this study, the effect of jet injection, location of the conductivity probe, aeration rate and jet Reynolds number on the mixing time are investigated. The created flow pattern was extracted for each condition and the results often analyzed on the basis of them. It is observed that, for low aeration rates, the injection of jet decreases the mixing time considerably. By increasing the aeration rate, the difference in mixing times between the two cases of jet injection and without jet is reduced. Results also show that the closer the probe is to encounter location of the jet and airflow, the lower the mixing time obtained. Dependence of mixing time on the probe location decreases by increasing the mixing intensity and eliminating dead zones. It is obtained, on the basis of Re_j and the amount of jet travelling in the vessel, increasing the aeration rate has different effects on the performance of mixing. Generally, four different trends for the variation of mixing time with increasing the aeration rate are observed.     

湍球塔烟气脱硫的化学动力学模型

在试验的基础上,对湍球塔的传质反应过程进行适宜的假设,用双膜理论加经验方法处理气 液两侧的传质,建立了湍球塔烟气脱硫的化学动力学模型,并用试验数据对模型进行验证,得到了比较好的效果,为进一步的大规模试验及工业放大创造了条件。     

电子束氨法技术在IEPE的研究进展

本文介绍了中国工程物理研究院环保工程研究中心(Institute of Environmental Protection Engi-neering,简称IEPE)在电子束氨法烟气脱硫脱硝技术(简称EA-FDG技术)的研究进展情况,对工艺流程、工业试验装置、工艺参数和工程设计进行了较全面的论述,展望了EA-FDG的发展方向。     

二氧化硫对石灰石的直接硫酸盐化作用的热重分析的研究与建模

The direct sulfation of limestone from different sources in Iran was studied in a thermogravimetric analyzer under atmospheric pressure. All limestone samples tested have higher than 97% CaCO3. Experimental conditions were as follows: particle size levels ranging from 1.6μm to 7.8μm, four level reaction temperatures (700°C,750°C, 800°C and 850°C), and two SO2 concentrations (2.4 × 10-3 and 3.2 × 10-3 mol.mol-i). The particle size and temperature showed dominant influences on the rate and level of conversion while the effect of SO2 concentration was weak. The shrinking core model can be used to describe the behavior of the sulfation process. The reaction kinetics and diffusion mechanism are both important in controlling the rate of the process. The two key parameters of the model, chemical rate constant Ks and effective diffusion coefficient Deff were obtained. Model predictions are in good agreement with the experimental data.     

烟气脱硫技术研究进展

总结了近年来国内外应用的几种主要脱硫工艺和正在研究开发的新脱硫工艺。对其中发生的化学反应、技术特点及存在的问题进行了详细的分析,并从技术、经济分析角度评估各种工艺,提出适合我国燃煤电厂情况的脱硫方案。     

几种常见的烟气脱硫技术

火力发电厂是我国最主要的烟气排放源，会产生大量的SQ及NOx,给大气环境造成了很大的危害。介绍了目前几种常见的烟气脱硫技术，并对一些新兴脱硫技术进行了展望。     

国内烟气脱硫技术及若干问题探讨

烟气脱硫是减少二氧化硫排放的有效方法。本文介绍了国内目前5种主要的烟气脱硫工艺,并对它们的优缺点、脱硫率等进行了对比分析。最后探讨了我国烟气脱硫技术存在的问题,同时针对所存在的问题提出建议。     

烟气还原脱硫催化剂的研究进展

综述了过渡金属氧化物、稀土氧化物、钙钛矿以及其它复合氧化物对催化还原SO2 为元素S的研究进展 ,重点介绍了各种催化剂在氢气、一氧化碳作还原剂时的催化作用及其催化机理     

天然气脱硫技术研究与展望

天然气作为一种清洁能源,在应对环境保护及能源安全等方面肩负着重要的使命。随着我国经济的不断高速发展,对清洁能源的需求也逐渐增加。现阶段,天然气正处于高速发展阶段,发展前景巨大。"十三五"期间,我国的能源环境问题将更加严峻,高含硫天然气技术面临气质和排放标准的严格要求,提高天然气中的硫回收率是当今天然气净化技术的主要研究方向。主要对国内外天然气脱硫采用的技术进行分析和对比,展望未来技术的发展方向。     

燃煤烟气脱硫技术研究进展

中国的大气污染主要以煤烟型为主,燃煤释放的二氧化硫对人类健康和生态环境系统等造成了严重的危害,因此控制二氧化硫的排放至关重要。分析了近年来中国的煤炭消耗量及二氧化硫排放量;概述了二氧化硫的排放源及烟气脱硫技术应用现状,总结了湿法、半干法、干法烟气脱硫技术的优缺点及适用范围;综述了国内外烟气脱硫技术发展概况;分别对传统烟气脱硫技术中的石灰石-石膏法、氨-硫酸铵法、循环流化床法以及新型烟气脱硫技术中的离子液循环吸收法、磷酸钠盐法、氧化铜法的原理、研究现状及发展前景做了具体论述;通过对比以上几种脱硫技术的工艺特征及经济性,指出未来中国烟气脱硫技术的发展方向。