A Novel Inertial Separator for CFB Boilers

2005 ◽  
Author(s):  
Han-Ping Chen ◽  
Qiao He ◽  
Shi-Hong Zhang ◽  
Chu-Guang Zheng ◽  
De-Chang Liu ◽  
...  
Keyword(s):  
Pressure Drop ◽  
Fine Particles ◽  
Circulating Fluidized Bed ◽  
Separation Efficiency ◽  
Scale Up ◽  
Low Pressure ◽  
Great Difficulty ◽  
Separation Mechanism ◽  
The Novel ◽  
Two Stage

Besides several cyclone separators, some inertial separators had also developed and applied in the circulating fluidized bed (CFB) boilers. The inertial separators have some advantages such as simple structure, small volume, low pressure drop, easy scale-up and so on. But almost every existing inertia separator has great difficulty in solving the main shortage of lower separation efficiency especially for fine particles. Based on the research for the separation mechanism and performances of inertial separators, the State Key Laboratory of Coal Combustion (SKLCC) had developed a novel inertial separator for CFB boilers. The patented separator improves the structure of the U-beam that is the separation element of U-beam separators of Studsvik Energiteknik (Sweden) and Babcok & Wilcox (USA). A ash channel is added to avoid re-entrainment of the separated solid downward along the U-beam. Test result indicates that the novel separator has great higher separation efficiency with the same pressure drop, compared with the U-beams at same conditions. The novel separator is more suitable for a larger CFB boiler or repowering projects as primary separator than the U-beams. The novel inertial separator had been used for designing 25 ∼ 420 tons of steam per hour (t/h) two-stage-recirculation CFB boilers. The two-stage-recirculation CFB boilers in capacity of 25 t/h and 65t/h had been put into operation. This paper presents the work on research, development and application of the novel inertial separator with high separation efficiency and low pressure drop.

Study on Pressure Drop Characteristics of a Two-Stage Swirler Separator

2021 ◽  
pp. 1-13
Author(s):  
Zhihui Wang ◽  
Xingkai Zhang ◽  
Ruiquan Liao ◽  
Yu Lei ◽  
Zhigang Fang
Keyword(s):  
Pressure Drop ◽  
Gas Flow ◽  
High Efficiency ◽  
Separation Efficiency ◽  
Movement Pattern ◽  
Superficial Velocity ◽  
Dominant Factor ◽  
Liquid Volume ◽  
Maximum Pressure ◽  
Two Stage

Summary The vane swirler separator is widely used in the separation process of wet natural gas owing to a small volume, high efficiency, economy, and environmental protection. In addition to the separation efficiency, the pressure drop is also an important technical and operational index for evaluating the performance of the swirler. In this study, the pressure drop of a swirler vane separator was studied through laboratory experiments and numerical simulations. Through the visualization experimental study of the liquid membrane formation rule and its movement pattern, the reduced gas velocity on the pressure drop was divided into three stages. For a gas superficial velocity less than 5.69 m/s, the effect of gas superficial velocity on the pressure drop was small; for a gas superficial velocity greater than 16.57 m/s, the pressure drop increased significantly with an increase in gas flow rate, and the maximum pressure drop was generated by the two-stage swirler, downstream of which the pressure decreased precipitously. We also observed that when the liquid volume content was less than 3%, the gas superficial velocity was the dominant factor affecting the change in the pressure drop. The average relative error of the pressure drop prediction model based on the conservation of the energy law was 6.16%, which indicated a high calculation accuracy.

Experimental Analysis of Air∕Oil Separator Performance

2008 ◽  
Vol 130 (6) ◽  
Author(s):  
K. Willenborg ◽  
M. Klingsporn ◽  
S. Tebby ◽  
T. Ratcliffe ◽  
P. Gorse ◽  
...  
Keyword(s):  
Particle Size ◽  
Pressure Drop ◽  
Droplet Size ◽  
Separation Efficiency ◽  
Optical Measurement ◽  
Air Flow ◽  
Measurement Techniques ◽  
Design Feature ◽  
Droplet Size Distribution ◽  
Separation Mechanism

Within the European research project (Advanced Transmission and Oil System Concepts), a systematic study of the separation efficiency of a typical aeroengine air∕oil separator design was conducted. The main objectives were to obtain a basic understanding of the main separation mechanisms and to identify the relevant parameters affecting the separation efficiency. The results of the study contribute to an optimized separator technology. Nonintrusive optical measurement techniques like laser diffraction and multiple wavelength extinction were applied to analyze the separation efficiency and identify potential optimization parameters. Oil mist with defined oil droplet size distribution was supplied to the breather. By simultaneously measuring particle size and oil concentration upstream and downstream of the breather, the separation mechanism was analyzed and the separation efficiency was assessed. In addition, the pressure drop across the separator was measured. The pressure drop is an important design feature and has to be minimized for proper sealing of the engine bearing chambers. The experimental programe covered a variation of air flow, oil flow, shaft speed, and droplet size. The main emphasis of the investigations was on the separation of small droplets with a diameter of up to 10μm. The following trends on separation efficiency of small droplets were observed: The separation efficiency increases with increasing rotational speed, with increasing particle size, and with decreasing air flow rate. In parallel, the pressure drop across the breather increases with increasing speed and increasing air flow.

Experimental Analysis of Air/Oil Separator Performance

2006 ◽  
Author(s):  
K. Willenborg ◽  
M. Klingsporn ◽  
S. Tebby ◽  
T. Ratcliffe ◽  
P. Gorse ◽  
...  
Keyword(s):  
Particle Size ◽  
Pressure Drop ◽  
Droplet Size ◽  
Separation Efficiency ◽  
Optical Measurement ◽  
Measurement Techniques ◽  
Design Feature ◽  
Droplet Size Distribution ◽  
Separation Mechanism ◽  
Oil Flow

Within the European research project ATOS (Advanced Transmission and Oil System Concepts) a systematic study of the separation efficiency of a typical aero-engine air/oil separator design was conducted. The main objectives were to obtain a basic understanding of the main separation mechanisms and to identify the relevant parameters affecting the separation efficiency. The results of the study contribute to an optimised separator technology. Nonintrusive optical measurement techniques like laser diffraction and multiple wavelength extinction were applied to analyse the separation efficiency and identify potential optimisation parameters. Oil mist with defined oil droplet size distribution was supplied to the breather. By simultaneously measuring particle size and oil concentration upstream and downstream of the breather the separation mechanism was analysed and the separation efficiency was assessed. In addition, the pressure drop across the separator was measured. The pressure drop is an important design feature and has to be minimised for proper sealing of the engine bearing chambers. The experimental programme covered a variation of airflow, oil flow, shaft speed, and droplet size. The main emphasis of the investigations was on the separation of small droplets with a diameter of up to 10 μm. The following trends on separation efficiency of small droplets were observed: the separation efficiency increases with increasing rotational speed, with increasing particle size and with decreasing air flow rate. In parallel, the pressure drop across the breather increases with increasing speed and increasing airflow.

Experimental Research on the Influence of Inlet Conditions of Corrugated Plate Dryer

2017 ◽  
Author(s):  
Mao Feng ◽  
Tian RuiFeng ◽  
Chen BoWen ◽  
He Wei
Keyword(s):  
Pressure Drop ◽  
Steam Generator ◽  
Experimental Research ◽  
Separation Efficiency ◽  
Experimental Studies ◽  
Separation Performance ◽  
Separation Mechanism ◽  
Airflow Velocity ◽  
Pressurized Water ◽  
Water Separation

Corrugated plate dryer is one of the key components of natural circulation steam generator in the pressurized water reactor nuclear power plant. It play a decisive role in the water separation system to making steam become a good quality after steam flow out of a vertical steam generator. With the increase of the reactor power in the future design, it requires that the performance of corrugated plate dryer must be increased in the characteristics of steam load, separating efficiency, volume and resistance to make sure that steam generators still produce qualified steam at higher steam loads and higher cycle magnitudes. In this paper, we have done some experimental studies on the corrugated plate dryer. And we concentrated on airflow parameters on the separation performance and resistance performance of dryer. (1) First of all, we have determined the experimental research program about this study, after this, we finished the design works of the test bench, and then we have completed the construction work based on the design works. (2) Afterwards, the flow and separation mechanism of the wave plate dryer was experimentally studied by means of parameter measurement and analysis combined with observation and recording. The effects of different inlet humidities and inlet velocity on separation efficiency, pressure drop and re-entrainment were studied. The above study shows that: (1) The separation efficiency of corrugated plate dryer is related to inlet humidity and inlet airflow velocity. The separation efficiency of corrugated plate dryer is increase with inlet humidity goes higher, and increased to reach a highest point then goes down when inlet airflow velocity increased. (2) The re-entrainment is related to inlet humidity. When inlet humidity increased, the inlet airflow critical velocity which lead to re-entrain would decrease. (3) The pressure drop of dryer is related to the inlet airflow velocity. When the inlet wind velocity increases, the pressure drop increases.

Efficiency of two-stage heating of water on CHP plant with turbines of type T-250/300-240

2019 ◽  
Vol 12 (3) ◽  
pp. 213-219
Author(s):  
E. T. Ilin ◽  
S. P. Pechenkin ◽  
A. V. Svetushkov ◽  
J. A. Kozlova
Keyword(s):  
Transition Period ◽  
Steam Pressure ◽  
Low Pressure ◽  
Heat Extraction ◽  
Two Stage ◽  
Permissible Level ◽  
Lower Heat ◽  
Operational Modes ◽  
Extraction Section ◽  
Supply Water

During non-heating and transition period, most of cogeneration turbines operate with a lower heat extraction section actuated only due to a number of restrictions on the maximum and minimum pressure levels in the upper and lower heat extraction sections at operation of the turbine. For turbines of model T-250/300-240, the minimum permissible level of steam pressure in the upper heat extraction section, according to manufacturer data, is set to 0.06 MPa. During the non-heating and transition period, the supply water temperature is usually set in the range of 70–75°С. In order to maintain that temperature of supply water, the steam pressure in the upper heat extraction section should be below the minimum permissible level. As a result, the turbine operates with only the low-pressure heat extraction section actuated, which ensures operation without restrictions, but with a lower efficiency. The authors have introduced a set of measures, which enable to avoid those restrictions and implement two-stage heating of supply water. In this case, on connection of the upper heating extraction section, the pressure in the same is maintained at the minimum permissible level. Heat output characteristics are provided by having some of supply water delivered bypassing the group of network heaters. This operational mode enables to increase the turbine actual heat drop, to reduce the cooling steam flow into the low-pressure section and, accordingly, into the condenser, and to reduce temperature drops in network water heaters. Results of the research of operational modes for turbines of type T-250/300-240 in the non-heating and transition period with one and two-stage heating are provided. The economic efficiency of proposed operational modes was researched, which shows the effectiveness of those modes during non-heating and transition period. The limits of the efficiency of using these modes are determined.

scholarly journals Clogging sensitivity of flow distributors designed for radially elongated hexagonal pillar array columns: a computational modelling

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Farideh Haghighi ◽  
Zahra Talebpour ◽  
Amir Sanati-Nezhad
Keyword(s):  
Pressure Drop ◽  
Aspect Ratio ◽  
Contact Zone ◽  
Separation Efficiency ◽  
Fluid Dynamic ◽  
Computational Modelling ◽  
Channel Width ◽  
Fluid Distribution ◽  
Design Parameters ◽  
Pillar Array

AbstractFlow distributor located at the beginning of the micromachined pillar array column (PAC) has significant roles in uniform distribution of flow through separation channels and thus separation efficiency. Chip manufacturing artifacts, contaminated solvents, and complex matrix of samples may contribute to clogging of the microfabricated channels, affect the distribution of the sample, and alter the performance of both natural and engineered systems. An even fluid distribution must be achieved cross-sectionally through careful design of flow distributors and minimizing the sensitivity to clogging in order to reach satisfactory separation efficiency. Given the difficulty to investigate experimentally a high number of clogging conditions and geometries, this work exploits a computational fluid dynamic model to investigate the effect of various design parameters on the performance of flow distributors in equally spreading the flow along the separation channels in the presence of different degrees of clogging. An array of radially elongated hexagonal pillars was selected for the separation channel (column). The design parameters include channel width, distributor width, aspect ratio of the pillars, and number of contact zone rows. The performance of known flow distributors, including bifurcating (BF), radially interconnected (RI), and recently introduced mixed-mode (MMI) in addition to two new distributors designed in this work (MMII and MMIII) were investigated in terms of mean elution time, volumetric variance, asymmetry factors, and pressure drop between the inlet and the monitor line for each design. The results show that except for pressure drop, the channel width and aspect ratio of the pillars has no significant influence on flow distribution pattern in non-clogged distributors. However, the behavior of flow distributors in response to clogging was found to be dependent on width of the channels. Also increasing the distributor width and number of contact zone rows after the first splitting stage showed no improvement in the ability to alleviate the clogging. MMI distributor with the channel width of 3 µm, aspect ratio of the pillars equal to 20, number of exits of 8, and number of contact zones of 3 exhibited the highest stability and minimum sensitivity to different degrees of clogging.

scholarly journals Study on the Leakage and Inter-Stage Pressure Drop Characteristics of Two-Stage Finger Seal

2021 ◽  
Vol 11 (5) ◽  
pp. 2239
Author(s):  
Hailin Zhao ◽  
Hua Su ◽  
Guoding Chen ◽  
Yanchao Zhang
Keyword(s):  
Pressure Drop ◽  
Pressure Difference ◽  
Radial Displacement ◽  
Mean Square ◽  
The Finite Element Method ◽  
Axial Pressure ◽  
Two Stage ◽  
One Stage ◽  
The One ◽  
Lower Contact

To solve the high leakage and high wear problems faced by sealing devices in aeroengines under the condition of high axial pressure difference, the two-stage finger seal is proposed in this paper. The finite element method and computational fluid dynamics (FEM/CFD) coupling iterative algorithm of the two-stage finger seal is developed and validated. Then the performance advantages of two-stage finger seal compared to the one-stage finger seal are studied, as well as the leakage and the inter-stage pressure drop characteristics of two-stage finger seal are investigated. Finally, the measure to improve the inter-stage imbalance of pressure drop of two-stage finger seal is proposed. The results show that the two-stage finger seal has lower leakage and lower contact pressure than the one-stage finger seal at high axial pressure difference, but there exists an inter-stage imbalance of pressure drop. Increasing the axial pressure difference and the root mean square (RMS) roughness of finger element can aggravate the imbalance of pressure drop, while the radial displacement excitation of rotor has little influence on it. The results also indicate that the inter-stage imbalance of pressure drop of the two-stage finger seal can be improved by increasing the number of finger elements of the 1st finger seal and decreasing the number of finger elements of the 2nd finger seal.

scholarly journals MXene-Ti3C2 assisted one-step synthesis of carbon-supported TiO2/Bi4NbO8Cl heterostructures for enhanced photocatalytic water decontamination

Nanophotonics ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 2077-2088 ◽  
Author(s):  
Daixun Jiang ◽  
Xun Sun ◽  
Xilu Wu ◽  
Shuai Zhang ◽  
Xiaofei Qu ◽  
...  
Keyword(s):  
Charge Separation ◽  
Photocatalytic Performance ◽  
Separation Efficiency ◽  
Salt Flux ◽  
The Novel ◽  
Water Contaminants ◽  
Photocatalytic Removal ◽  
One Step ◽  
Charge Separation Efficiency ◽  
Perovskite Type

AbstractThe strategy to improve the photocatalytic removal efficiencies towards organic pollutants is still a challenge for the novel Sillen–Aurivillius perovskite type Bi4NbO8Cl. Herein, we report carbon-supported TiO2/Bi4NbO8Cl (C-TiO2/Bi4NbO8Cl) heterostructures with enhanced charge separation efficiency, which were fabricated via molten-salt flux process. The carbon-supported TiO2 particles were derived from MXene Ti3C2 precursors, and attached on plate-like Bi4NbO8Cl, acting as electron-traps to achieve supressed recombination of photo-induced charges. The improved charge separation confers C-TiO2/Bi4NbO8Cl heterostructures superior photocatalytic performance with 53% higher than pristine Bi4NbO8Cl, towards rhodamine B removal with the help of photo-induced holes. Moreover, the C-TiO2/Bi4NbO8Cl heterostructures can be expanded to deal with other water contaminants, such as methyl orange, ciprofloxacin and 2,4-dichlorophenol with 44, 25 and 13% promotion, respectively, and thus the study offers a series of efficient photocatalysts for water purification.

Sign in / Sign up

Export Citation Format

Share Document