Numerical simulation and field test study of desulfurization wastewater evaporation treatment through flue gas

2014 ◽  
Vol 70 (7) ◽  
pp. 1285-1291 ◽  
Author(s):  
Jia-jia Deng ◽  
Liang-ming Pan ◽  
De-qi Chen ◽  
Yu-quan Dong ◽  
Cheng-mu Wang ◽  
...  
Keyword(s):  
Field Test ◽  
Flue Gas ◽  
Cfd Simulation ◽  
Electrostatic Precipitator ◽  
Negative Impact ◽  
Positive Impact ◽  
Field Tests ◽  
Gas Temperature ◽  
Simulation Results ◽  
Desulfurization Wastewater

Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 μm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment.

scholarly journals CFD Simulation Research on Agglomeration between Coal-fired Ash Fine Particulate and Atomized Droplets

2020 ◽  
Vol 165 ◽  
pp. 01006
Author(s):  
Yiquan Guo ◽  
Junying Zhang
Keyword(s):  
Power Plant ◽  
Flow Field ◽  
Cfd Simulation ◽  
Negative Impact ◽  
Droplet Diameter ◽  
Temperature Drop ◽  
Operating Conditions ◽  
Gas Temperature ◽  
Simulation Research ◽  
Agglomeration Process

In this paper, a collision model between atomized droplets of agglomeration solution and particles is established. On this basis, the effects of flue gas temperature, atomized droplet diameter and other factors on the particle agglomeration process are studied. In addition, the evaporation model of agglomeration solution in the flue of a power plant is established for the coal-fired unit of power plant. Through CFD software, the variation of flow field velocity, temperature and pressure in the flue is simulated to determine whether the chemical agglomeration technology has negative impact on the actual operating conditions of the power plant. The simulation results show that the velocity and pressure of the flow field in the flue have no obvious change after the agglomerating agent is injected. Besides, the temperature drop of about 7°C. The droplets evaporate completely at a distance of 7-8 m after spraying. The evaporation time of droplets is within 1.6 s.

Influence of the electrostatic precipitator and the flue gas temperature on concentrations of organic compounds

Chemosphere ◽  
1993 ◽  
Vol 27 (4) ◽  
pp. 547-553 ◽  
Author(s):  
W. Funcke ◽  
A. Hovemann ◽  
P. Luthardt ◽  
E. Manske
Keyword(s):  
Organic Compounds ◽  
Flue Gas ◽  
Electrostatic Precipitator ◽  
Gas Temperature

Fundamental Research and Demonstration Project of Evaporation Treatment of Wastewater from FGD in Flue Gas Duct

2013 ◽  
Vol 864-867 ◽  
pp. 434-437 ◽  
Author(s):  
Dan Ning Jiang ◽  
Hai Wei Sha ◽  
Guo Hui Gong ◽  
Jing Song ◽  
Hai Tao Xu ◽  
...  
Keyword(s):  
Flue Gas ◽  
Electrostatic Precipitator ◽  
Demonstration Project ◽  
Power Company ◽  
Company Limited ◽  
Fundamental Research ◽  
Zero Discharge ◽  
New Processing ◽  
Domestic Power ◽  
Desulfurization Wastewater

The desulfurization wastewater is a kind of intractable wastewater which comes from the process of wet desulfurization. There are many shortcomings of traditional development methods. Desulfurization wastewater evaporation treatment in flue gas duct as a new processing technology. This approach of evaporating desulfurization wastewater by flue gas is feasible. The feasibility of the demonstration project of boiler flue gas treating wastewater on 4# boiler in Changshu Power Company limited was analyzed; the computational fluid dynamics (CFD) software FLUENT was adopted to simulated the pressure field and velocity field in the outlet flue pipes of air pre-heater. The concrete arrangement mode and the number of the spray lances were determined by calculations. The temperature of the flue gas is tested after the system was put into operation. The results showed that this technology can realize the desulfurization wastewater with zero discharge without hurting the work of electrostatic precipitator. The demonstration project is the first of its kind in domestic power industry; this study provides experiences and references of power plant desulfurization wastewater with zero discharge.

Research of Improving the Technique of Electrostatic Collection to High Resistivity Dust by Humidifying and Cooling through Ultrasonic Atomization

2014 ◽  
Vol 1010-1012 ◽  
pp. 789-795
Author(s):  
Li Juan Guo ◽  
Wen Ge Hao ◽  
Xiao Zhen Ren ◽  
Kuan Zhang
Keyword(s):  
Flue Gas ◽  
Electrostatic Precipitator ◽  
Specific Resistance ◽  
Dust Removal ◽  
Electrical Heating ◽  
High Resistivity ◽  
Gas Temperature ◽  
Ultrasonic Atomization ◽  
Gas Humidification ◽  
Test Result

In order to study the effect of dust removal in the electrostatic precipitator under the influence of change of temperature and air moisture of flue gas, the ultrasonic atomization and electrical heating has been adopted for simulated gas to change its air moisture and temperature. The specific resistance of fly ash of fluidized bed boiler, the V-j characteristics of the precipitator model and the efficiency of dust removal has been tested in gas working conditions. The measured results of dust specific resistance shows that: when the temperature of gas at range of 100°C to 150°C, the specific resistance of dust was lower when the air moisture is at 23.73% than at 5.21%, especially when the gas temperature is below 120°C, the specific resistance of dust reduce more,and it can reach the orders of magnitude at1010Ω·cm when the moisture of 23.73%; then keep the temperature at 150°C and make the moisture increased, the specific resistance of dust is decreased, however it is still more than 1011Ω·cm when the moisture is increased to 23.73%. The measured results of V-j characteristics of the precipitator model shows that: when the moisture keeps at 23.73% and the temperature is below 120°C, the electric field does not occur the phenomenon of anti-corona. The test result of the efficiency of dust removal indicated that: when we make the moisture increased to 23.73% and the gas temperature below 120°C, the efficiency of dust removal shows a significant increase. The results confirmed that we can improve the purification efficiency of high resistivity dust through flue gas humidification and proper temperature maintain.

Study on Mathematical Simulation of Nitrogen Oxides (NOx) Formation of Coal-Fired Boiler

2011 ◽  
Vol 354-355 ◽  
pp. 319-324
Author(s):  
Li Jun Heng ◽  
Kun Jie Duan ◽  
Chang Zheng He
Keyword(s):  
Nitrogen Oxides ◽  
Mathematical Models ◽  
Mathematical Simulation ◽  
Field Test ◽  
Theoretical Basis ◽  
Influence Factors ◽  
Field Tests ◽  
Test Conditions ◽  
Fluent Software ◽  
Simulation Results

There exist certain limitations to research the law and influence factors of the nitrogen oxides formation only with the help of field tests, because the nitrogen oxides formation of the boiler is influenced by various factors. The flow, combustion mathematical models interrelated and so on are established taking the 410t/h boiler fired tangentially as a prototype by the use of the fluent software. All the mathematical models are verified and modified with the aid of routine field test data, and the accuracy and reliability of the mathematical models are improved. Then NOx formation performance is stimulated in allusion to the influence factors without field test conditions. The mathematical simulation results show that mathematical models can provide a sufficient theoretical basis to analyze accurately combustion and NOx formation law in furnace, and the deficiencies of field tests have been made up.

scholarly journals High Temperature Modification of SNCR Technology and its Impact on NOx Removal Process

2018 ◽  
Vol 180 ◽  
pp. 02009
Author(s):  
Tomáš Blejchař ◽  
Jaroslav Konvička ◽  
Bernd von der Heide ◽  
Rostislav Malý ◽  
Miloš Maier
Keyword(s):  
Nitrogen Oxides ◽  
Flue Gas ◽  
Cfd Simulation ◽  
Catalytic Reduction ◽  
Gas Temperature ◽  
Nitrous Oxides ◽  
Removal Process ◽  
Emission Limit ◽  
Injection Region ◽  
High Temperature Modification

SNCR (Selective non-catalytic reduction) Technology is currently being used to reach the emission limit for nitrogen oxides at fossil fuel fired power plant and/or heating plant and optimum temperature for SNCR process is in range 850 - 1050°C. Modified SNCR technology is able to reach reduction 60% of nitrogen oxides at temperature up to 1250°C. So the technology can also be installed where the flue gas temperature is too high in combustion chamber. Modified SNCR was tested using generally known SNCR chemistry implemented in CFD (Computation fluid dynamics) code. CFD model was focused on detail simulation of reagent injection and influence of flue gas temperature. Than CFD simulation was compared with operating data of boiler where the modified SNCR technology is installed. By comparing the experiment results with the model, the effect on nitrous oxides removal process and temperature of flue gas at the injection region.

scholarly journals A virtual prototype for performance analysis of electropneumatic brake on metro trains

2020 ◽  
Vol 12 (6) ◽  
pp. 168781402092627
Author(s):  
Jianyong Zuo ◽  
Jingxian Ding ◽  
Cheng Liu ◽  
Zhuojun Luo
Keyword(s):  
Performance Analysis ◽  
Field Test ◽  
Field Tests ◽  
Virtual Prototype ◽  
Bench Test ◽  
Initial Speed ◽  
Test Results ◽  
Braking Distance ◽  
Simulation Results ◽  
And Performance

In order to facilitate system design and performance analysis, a virtual prototype for metro train electropneumatic brakes is proposed. A virtual braking environment that consists of a three-car train model and six electropneumatic brakes model is elaborated. The virtual braking environment can be used to research the relation between braking response and electropneumatic brake’s parameters and to simulate axle loading transfer. By comparing the simulation results with bench test data, the electropneumatic brake model is proven to be quite accurate. Based on the proposed virtual prototype, a test train brake is designed, and a couple of field tests are carried out. The average deceleration of electropneumatic compound service brake at the initial speed of 45 km/h is 0.83 m/s2, the braking distance is 94 m, and that of pure air service brake at the speed of 43 km/h is 0.64 m/s2, the braking distance is 111 m. The field test results satisfy the test train requirements, which further proves the effectiveness of the proposed virtual prototype.

scholarly journals Numerical Investigation on the Evaporation Performance of Desulfurization Wastewater in a Spray Drying Tower without Deflectors

Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1022
Author(s):  
Debo Li ◽  
Ning Zhao ◽  
Yongxin Feng ◽  
Zhiwen Xie
Keyword(s):  
Spray Drying ◽  
Droplet Size ◽  
Flow Rate ◽  
Flue Gas ◽  
Gas Flow ◽  
Initial Temperature ◽  
Gas Temperature ◽  
Gas Flow Rate ◽  
Complete Evaporation ◽  
Desulfurization Wastewater

The desulfurization wastewater evaporation technology with flue gas has been widely applied to dispose of desulfurization wastewater. This paper investigates the effect of flue gas flow rate and temperature, wastewater flow rate and initial temperature, and droplet size on the evaporation performance of the desulfurization wastewater in a spray drying tower without deflectors. The results show that the flue gas flow rate and temperature affect the evaporation performance of desulfurization wastewater. The larger flow rate and higher temperature of flue gas correspond to the faster evaporation speed and the shorter complete evaporation distance of the wastewater droplet. Decreasing the flow rate and increasing the initial temperature of the desulfurization wastewater is advantageous to enhance the evaporation speed and shorten the complete evaporation distance of the wastewater droplet. Reducing the droplet size is beneficial to improve the evaporation performance of the desulfurization wastewater. The orthogonal test results show that the factors affecting droplet evaporation performance are ranked as follows: flue gas flow rate > wastewater flow rate > flue gas temperature > wastewater initial temperature > droplet size. Considering the evaporation ratio and the complete evaporation distance, the optimal setting is 14.470 kg/s for flue gas flow rate, 385 °C for flue gas temperature, 0.582 kg/s for wastewater flow rate, 25 °C for wastewater initial temperature, and 60 μm for droplet size. These studied results can provide valuable information to improve the operational performance of the desulfurization wastewater evaporation technology with flue gas.

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