Cyclic Operation of Flash and Column Flash Distillation

HAYNES® alloy HR-120® has been identified as a potential alloy for the manufacture of primary surface recuperators. Primary surface recuperator components have been manufactured from HR-120, and actual microturbine testing is on going. Initial engine test results indicate the formation of a protective oxide scale that is resistant to both steady-state and cyclic operation with no evidence of accelerated attack, and which is likely to meet or exceed the desired 80,000 hour component life.

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Numerical and Experimental Investigations of the Transient Thermal Behavior of a Steam By-Pass Valve at Steam Temperatures Beyond 700 °C

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4029040 ◽

2015 ◽

Vol 7 (1) ◽

Cited By ~ 4

Author(s):

Anis Haj Ayed ◽

Martin Kemper ◽

Karsten Kusterer ◽

Hailu Tadesse ◽

Manfred Wirsum ◽

...

Keyword(s):

Thermal Behavior ◽

Power Plants ◽

Numerical Approach ◽

Life Assessment ◽

Experimental Investigations ◽

Steam Power ◽

Steam Power Plants ◽

Cyclic Operation ◽

Measurement Results ◽

Transient Thermal

Increasing the efficiency of steam power plants is important to reduce their CO2 emissions and can be achieved by increasing steam temperatures beyond 700 °C. Within the present study, the thermal behavior of a steam by-pass valve subject to cyclic operation with 700 °C steam is investigated experimentally and numerically. An innovative numerical approach was applied to predict the valve’s thermal behavior during cyclic operation, which is essential for fatigue life assessment of such a component. Validation of the applied numerical approach has shown good agreement with measurement results, indicating the potential of its application for the valve design process.

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The optimisation and design of large scale multi-stage flash distillation plants

Desalination ◽

10.1016/s0011-9164(00)84008-4 ◽

1966 ◽

Vol 1 (1) ◽

pp. 61-76 ◽

Cited By ~ 7

Author(s):

D.W. Clelland ◽

J.M. Stewart

Keyword(s):

Large Scale ◽

Multi Stage ◽

Flash Distillation

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Conjugated Heat Transfer in Skirt Hot Box in Pressure Vessels

Volume 4: Fatigue and Fracture, Heat Transfer, Internal Combustion Engines, Manufacturing, and Technology and Society ◽

10.1115/esda2006-95729 ◽

2006 ◽

Author(s):

Hossein Shokouhmand ◽

Manoochehr Bozorgmehrian

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Temperature Gradient ◽

Thermal Stresses ◽

Weld Line ◽

Pressure Vessels ◽

Conductive Heat ◽

Air Pocket ◽

Cyclic Operation ◽

Conjugated Heat Transfer

Pressure vessels are common equipment in oil, gas and petrochemical industries. In a hot containing fluid vessel, excessive temperature gradient at junction of skirt to head (weld line), can cause unpredicted high thermal stresses; Thereby fracture of the vessel may occur as a result of cyclic operation. Providing a hot box (air pocket) in crotch space is a economical, applicable and easy mounted method in order to reduce the intensity of thermal stresses. Natural convection due to temperature difference between the wall of pocket, will absorb heat near the hot wall (head of the vessel) and release that near the cold wall (skirt of the vessel), then the skirt wall conducts heat to the earth as a fin. This conjugated heat transfer removes the temperature gradient boundary at welded junction. This phenomena will lead the temperature gradient on the weld line from a sudden to smooth behavior, thereby the skirt-head junction, that is a critical region, could be protected from excessive thermal stresses. In this paper the profit of hot box and conjugated heat transfer in cavity has been demonstrated experimentally. As a result it is shown that the conductive heat transfer through the skirt (which acts as a fin) ensures the continuation of natural convection in the box. Also the governing equations has been solved numerically and compared with experimental results.

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Cyclic operation of a fixed-bed pressure and temperature swing process for CO2 capture: Experimental and statistical analysis

International Journal of Greenhouse Gas Control ◽

10.1016/j.ijggc.2012.10.018 ◽

2013 ◽

Vol 12 ◽

pp. 35-43 ◽

Cited By ~ 24

Author(s):

S. García ◽

M.V. Gil ◽

J.J. Pis ◽

F. Rubiera ◽

C. Pevida

Keyword(s):

Statistical Analysis ◽

Co2 Capture ◽

Fixed Bed ◽

Cyclic Operation ◽

Temperature Swing

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Redox Oxides-Based Solar Thermochemistry and Its Materialization to Reactor/Heat Exchanger Concepts for Efficient Solar Energy Harvesting, Transformation and Storage

Journal of Solar Energy Engineering ◽

10.1115/1.4042226 ◽

2019 ◽

Vol 141 (2) ◽

Cited By ~ 4

Author(s):

Christos Agrafiotis ◽

Mathias Pein ◽

Dimitra Giasafaki ◽

Stefania Tescari ◽

Martin Roeb ◽

...

Keyword(s):

Scanning Calorimetry ◽

Chemical Expansion ◽

Solar Energy Harvesting ◽

Cyclic Operation ◽

Heat Effects ◽

Carbon Dioxide Splitting ◽

Oxygen Pumping ◽

Coefficient Of Linear Expansion ◽

A Site

Ca-Mn-based perovskites doped in their A- and B-site were synthesized and comparatively tested versus the Co3O4/CoO and (Mn,Fe)2O3/(Mn,Fe)3O4 redox pairs with respect to thermochemical storage and oxygen pumping capability, as a function of the kind and extent of dopant. The perovskites' induced heat effects measured via differential scanning calorimetry are substantially lower: the highest reaction enthalpy recorded by the CaMnO3–δ composition was only 14.84 kJ/kg compared to 461.1 kJ/kg for Co3O4/CoO and 161.0 kJ/kg for (Mn,Fe)2O3/(Mn,Fe)3O4. Doping of Ca with increasing content of Sr decreased these heat effects; more than 20 at % Sr eventually eliminated them. Perovskites with Sr instead of Ca in the A-site exhibited also negligible heat effects, irrespective of the kind of B site cation. On the contrary, perovskite compositions characterized by high oxygen release/uptake can operate as thermochemical oxygen pumps enhancing the performance of water/carbon dioxide splitting materials. Oxygen pumping via Ca0.9Sr0.1MnO3–δ and SrFeO3–δ doubled and tripled, respectively, the total oxygen absorbed by ceria during its re-oxidation versus that absorbed without their presence. Such effective pumping compositions exhibited practically no shrinkage during one heat-up/cool-down cycle. However, they demonstrated an increase of the coefficient of linear expansion due to the superposition of “chemical expansion” to thermal-only one, the effect of which on the long-term dimensional stability has to be further quantified through extended cyclic operation.

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Numerical analysis of heat exchange process in the biomass carbonisation reactor

MATEC Web of Conferences ◽

10.1051/matecconf/201925205019 ◽

2019 ◽

Vol 252 ◽

pp. 05019 ◽

Cited By ~ 1

Author(s):

Robert Zarzycki ◽

Justyna Jędras

Keyword(s):

Heat Transfer ◽

Heat Exchange ◽

Numerical Analysis ◽

Exchange Process ◽

Geometrical Model ◽

Heating Time ◽

Heating Process ◽

Hot Air ◽

Cyclic Operation ◽

Heat Exchange Process

The study presents the problem of heat exchange in the biomass carbonisation reactor with cyclic operation. Based on the actual parameter of the biomass carbonisation reactor, a geometrical model was developed, and the computation of the heating process was conducted for two cases: an empty reactor and a filled reactor. Its result demonstrated that for the analysed configuration of the reactor, the process of heating biomass in the containers is limited by the capability of heat transfer to the biomass in the container. The results suggest opportunities for the improved heat exchange in the reactor and, accordingly, shortening heating time through installation of the system that forces circulation of hot air inside the reactor.

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