Improvement Research on Furnace Flue Tube of Three Medium Dryer System Used by Fan Mills

2013 ◽  
Vol 448-453 ◽  
pp. 3301-3305
Author(s):  
Zhen Yao Qu ◽  
Qiang Wang
Keyword(s):  
Low Temperature ◽  
Flue Gas ◽  
Large Scale ◽  
Gas Temperature ◽  
Test Bed ◽  
Hot Air ◽  
High Temperature Furnace ◽  
Water Side ◽  
Unit Capacity ◽  
Temperature Furnace

Pulverizing system equipped by fan mills uses three medium (ie. low-temperature furnace smoke, high-temperature furnace smoke, hot air) for drying coal, especially in large-scale plants burning lignite. A constantly increasing unit capacity leads to a more complicated design for pulverizing system, with a heavier weight of furnace smoke tube. This paper focuses on a research of water-cooled membrane flue tube instead of traditional inner and outer insulation tube through experiments like changing water side parameters to replace the low-temperature flue pipe from three medium to two medium (ie. adjustable-temperature furnace smoke, hot air). This paper studies heat transfer coefficient of water-cooled furnace smoke pipe at different flow rate and flue gas temperature though a established water-cooled furnace smoke pipe test bed. It is using a certain mathematic method to obtain dimensionless relationship among Nu, Re, Pr and obtain the dimensionless rule equation of water-cooled furnace smoke tube.

Effect of Desulfurization Ash with Different Desulfurization Temperature and Gypsum Content on the Fluidity, Strength and Rebar Protection of Cement Based Materials

2010 ◽  
Vol 168-170 ◽  
pp. 940-944
Author(s):  
Xiao Dong Wen ◽  
Guo Song Li ◽  
Jiu Yong Song ◽  
Zhi Nan Gao
Keyword(s):  
High Temperature ◽  
Fly Ash ◽  
Low Temperature ◽  
Flue Gas ◽  
Development Trend ◽  
Weight Percentage ◽  
Steel Rebar ◽  
High Temperature Furnace ◽  
Gypsum Content ◽  
Temperature Furnace

Depending on the desulfurization reaction temperature，it can be divided into fly ash generated at high-temperature furnace zone and at low-temperature flue gas zone. For simulating those two kinds of desulfurization ash, the ordinary fly ash mixed with different weight percentage of CaSO4•2H2O is divided into 2 groups, the first group is followed by calcining at 900 , another drying at 100 . And then by the experiment of workability, strength and steel rebar protection, the effect of morphology and amount of gypsum on material properties and the pretreatment method are studied. The results show that: compared with ordinary fly ash, those two kinds of desulfurization ash can improve workability, but the improving ability of desulfurization ash at high-temperature furnace zone weaker than another’s, in addition, amount of gypsum in desulfurization ash on fluidity has a threshold; Secondly, desulfurization ash can decrease strength, and the early strength of desulfurization ash at high-temperature furnace zone higher than another’s, but the development trend of later strength is in the opposite direction. Thirdly, those two kinds of desulfurization ash are harmless for steel rebar, and the steel rebar’s passive film compactness is followed desulfurization ash formed at low-temperature flue gas zone＞desulfurization ash formed at high-temperature furnace zone＞ordinary fly ash.

Energy-Saving Analysis of 215MW Cogeneration Boiler Adding Low Temperature Economizer

2013 ◽  
Vol 448-453 ◽  
pp. 2777-2780 ◽  
Author(s):  
Yan Feng Liu ◽  
Shi Ping Li ◽  
Xiang Hong Li
Keyword(s):  
Low Temperature ◽  
Flue Gas ◽  
Waste Heat ◽  
Natural Circulation ◽  
Peak Load ◽  
Exhaust Gas ◽  
Gas Temperature ◽  
Bag Filter ◽  
Actual Operation ◽  
Exhaust Gas Temperature

A 215MW cogeneration B&W670/13.7-M type high-pressure natural circulation boilers, the exhaust gas temperature is set as 143 °C, while in the actual operation, the average exhaust gas temperature is 155 °C, and when the unit is running at full capacity in summer the highest exhaust gas temperature is 169.6 °C. In order to satisfy the normal operating temperature of bag filter in summer peak load, and recover low temperature waste heat of fule gas, low temperature economizer is added to the thermal system. Therefore, low-temperature economizers are respectively added in four flues which are between the outlet of the air preheater and the entrance of the bag filter, this will achieve the purpose of reducing flue gas temperature by transferring heat between condensate and flue gas, ensuring the units safe operating and improving the overall operating performance of the boiler.

scholarly journals CFD ANALYSIS OF ECONOMIZER IN A TENGENTIAL FIRED BOILER

2013 ◽  
pp. 143-147
Author(s):  
KRUNAL P. MUDAFALE ◽  
HEMANT S. FARKADE
Keyword(s):  
Flue Gas ◽  
Power Plants ◽  
Large Scale ◽  
Thermal Power ◽  
Three Dimensional ◽  
Geometrical Model ◽  
Gas Temperature ◽  
Three Dimensional Model ◽  
The Individual ◽  
Side Flow

This paper presents a simulation of the economizer zone, which allows for the condition of the shell-side flow and tube-side and tube-wall, thermal fields, and of the shell-tube heat-exchange. Selection of the economizer zone from the thermal power plant only because, it is found trends of failure that the economizer is the zone where the leakages are found more. The maximum number of cause of failure in economizer unit is due to flue gas erosion. The past failure details revels that erosion is more in U-bend areas of Economizer Unit because of increase in flue gas velocity near these bends. But it is observed that the velocity of flue gases surprisingly increases near the lower bends as compared to upper ones. The model is solved using conventional CFD techniques by STAR- CCM+ software. In which the individual tubes are treated as sub-grid features. A geometrical model is used to describe the multiplicity of heat-exchanging structures and the interconnections among them. The Computational Fluid Dynamics (CFD) approach is utilised for the creation of a three-dimensional model of the economizer coil. With equilibrium assumption applied for description of the system chemistry. The flue gas temperature, pressure and velocity field of fluid flow within an economizer tube using the actual boundary conditions have been analyzed using CFD tool. Such as the ability to quickly analyse a variety of design options without modifying the object and the availability of significantly more data to interpret the results. This study is a classic example of numerical investigation into the problem of turbulent reacting flows in large scale furnaces employed in thermal power plants for the remediation of ash deposition problems. And the experimental setup is from Chandrapur Super Thermal Power Station, Chandrapur having the unit no IV of 210 MW energy generations.

scholarly journals Study on denitration performance of multi element modified MIL-101 (Fe) at low temperature

2022 ◽  
Vol 355 ◽  
pp. 01023
Author(s):  
Shuqin Wang ◽  
Xiaoxue Li ◽  
Jinjin Wu
Keyword(s):  
Low Temperature ◽  
Flue Gas ◽  
Selective Adsorption ◽  
Amino Group ◽  
Optimal Conditions ◽  
Gas Temperature ◽  
High Concentration ◽  
Microwave Hydrothermal ◽  
Catalytic Role ◽  
As Adsorption

MIL-101 (Fe) was modified by amino group and doped by Cu and Co elements by microwave hydrothermal method. The effect of SCR denitrification at low temperature was investigated with high concentration of NOx as adsorption object. The results show that when the flue gas temperature is 200 °C and the NOx concentration is up to 1640 mg/m3, the removal efficiency of NOx can reach 86% under the optimal conditions, which is 1.5 times higher than that before modification. In addition, the characterization results indicated that the specific surface area of the modified catalyst increased, the thermal stability was good at low temperature, the selective adsorption capacity of NO was enhanced, and the doping played a synergistic catalytic role. It can be used for flue gas denitration in various industries.

The Comparison and Analysis of Low-Temperature Economizer Configuration Scheme

2014 ◽  
Vol 543-547 ◽  
pp. 673-676 ◽  
Author(s):  
Yan Feng Liu ◽  
Peng Cheng Wang ◽  
Shao Shan Zhang
Keyword(s):  
Low Temperature ◽  
Flue Gas ◽  
Water Side ◽  
Comparison And Analysis ◽  
Configuration Scheme

Low temperature economizer is an efficient way to recover the flue gas waste and to improve the efficiency of the boiler. Several basic layout of low temperature economizer are introduced in this paper. Layout is divided into flue gas side arrangement and water side arrangement. In this paper, combined with the parameters of a 600 mw, the economy of the different configuration is calculated and compared.

Analysis of Exhausting Flue Gas Temperature Abnormal Accompanied with the Boiler Load Changing

2013 ◽  
Vol 805-806 ◽  
pp. 1836-1842
Author(s):  
Qing Feng Zhang ◽  
Zhen Xin Wu ◽  
Zhen Ning Zhao
Keyword(s):  
Heat Transfer ◽  
Power Plant ◽  
Flue Gas ◽  
Gas Flow ◽  
Thermal Power ◽  
Transfer Principle ◽  
Air Leakage ◽  
Gas Temperature ◽  
Boiler Load ◽  
Hot Air

Based on the heat-transfer principle of air pre-heater, the influence mode of the changes of the air flow, the flue gas flow, the air leakage in different locations, to the temperature of the hot air and the exhausting gas was researched. The problem of a pulverized coal fired boiler, No.2, of a Thermal Power Plant, which the deviation of exhausting flue gas temperature increased to an abnormal extend when the boiler load rise up quickly was analyzed, the fault position and fault reason were located exactly, and the fault was eradicated by equipment maintenance at last. The results of this study have a certain significance to solve similar problems.

New high- and low-temperature apparatus for synchrotron polycrystalline X-ray diffraction

1998 ◽  
Vol 5 (3) ◽  
pp. 929-931 ◽  
Author(s):  
C. C. Tang ◽  
G. Bushnell-Wye ◽  
R. J. Cernik
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Closed Cycle ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Temperature Furnace ◽  
Wide Range ◽  
Powder Samples ◽  
Heater Coil ◽  
Temperature Furnace

A high-temperature furnace with an induction heater coil and a cryogenic system based on closed-cycle refrigeration have been assembled to enhance the non-ambient powder diffraction facilities at the Synchrotron Radiation Source, Daresbury Laboratory. The commissioning of the high- and low-temperature devices on the high-resolution powder diffractometer of Station 2.3 is described. The combined temperature range provided by the furnace/cryostat is 10–1500 K. Results from Fe and NH4Br powder samples are presented to demonstrate the operation of the apparatus. The developments presented in this paper are applicable to a wide range of other experiments and diffraction geometries.

scholarly journals Modification and Application of Low and Low Temperature Economizer in Dezhou Power Plant

2021 ◽  
Vol 271 ◽  
pp. 01022
Author(s):  
Qiudong Hu
Keyword(s):  
Power Plant ◽  
Low Temperature ◽  
Flue Gas ◽  
Power Plants ◽  
Waste Heat ◽  
National Policy ◽  
Dust Removal ◽  
Gas Temperature ◽  
Coal Consumption ◽  
Waste Heat Recovery System

At present, the exhaust gas temperature of coal-fired power plants is 125-150℃, and the emission of high-temperature flue gas causes the loss of excess heat and wastes. For this kind of phenomenon, the waste heat recovery system is researched and designed, combined with the combination of a low-temperature economizer in a coal-fired power plant in Dezhou. The heater, through the low-temperature economizer combined with the heater system, reduces coal consumption for power generation, reduces flue gas emissions, while reducing dust specific resistance, improving dust removal efficiency of electric dust removal, and reducing dust emissions. This project responds to national policy guidelines.

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