Ash in Gas Turbines Burning Magnesium-Treated Residual Fuel

1974 ◽  
Vol 96 (2) ◽  
pp. 134-137
Author(s):  
K. W. Lay
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Graphical Method ◽  
Condensed Phases ◽  
Experimental Measurements ◽  
Ash Composition ◽  
The Stability ◽  
Magnesium Vanadates ◽  
Stability Limits

The equilibrium ash composition in a magnesium treated residual fuel-fired gas turbine is considered in detail. The stability of the condensed phases of interest—MgO, MgSO4, and the magnesium vanadates are shown to be determined by the temperature and the equilibrium SO3 pressure at the deposit. The ash present will depend on these parameters as well as the Mg : V ratio in the ash. A thermodynamic treatment of the ternary MgO-V2O5-SO3 system is presented and experimental measurements of the stability limits of Mg3V2O8 and Mg2V2O7 are presented. A simple graphical method is described for representing the condensed phases present in ash for any Mg : V ratio and for temperatures and equilibrium SO3 pressures of interest in gas turbines.

Gas Turbines in Alternative Fuel Applications: How to Predict the Stability of Olefin-Containing Process Gases

2003 ◽  
Author(s):  
P. A. Glaude ◽  
O. Mahier ◽  
V. Warth ◽  
R. Fournet ◽  
M. Moliere ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Alternative Fuel ◽  
Liquefied Petroleum Gas ◽  
Gaseous Fuels ◽  
Process Gas ◽  
History Of ◽  
Process Gases ◽  
Heavy Duty Gas Turbine ◽  
The Stability

Throughout the history of combustion engines, the Heavy Duty Gas Turbine stands out as the most fuel-flexible prime mover in the field. This gas turbine (GT) is suited for a rich portfolio of gaseous fuels that include: natural gas, liquefied petroleum gas, coal and biomass-derived syngases, and a great variety of process gases with diverse compositions (hydrogen, carbon monoxide, olefins, etc.). Process gas fuels provide a promising array of alternative fuel opportunities in the major sectors of the industry such as the Coal, Oil & Gas, Steel, Chemical and Petrochemical branches. In an increasingly uncertain fuel environment, this significant match between gas turbine capabilities and the energy schemes of industrial plants can lead to further business opportunities.

Experimental Study on Lean Blowout Limits of Turbulent Premixed Hydrogen/Ammonia/Air Mixtures

2021 ◽  
Author(s):  
Andreas Goldmann ◽  
Friedrich Dinkelacker
Keyword(s):  
Gas Turbines ◽  
Measurement Procedure ◽  
Liquid Fuels ◽  
Special Focus ◽  
Atmospheric Conditions ◽  
Ammonia Content ◽  
Lean Blowout ◽  
Combustion Properties ◽  
The Stability ◽  
Stability Limits

Abstract As the demand for greenhouse gas neutral transportation and power generation solutions is growing, alternative carbon-free fuel such as hydrogen (H2) and ammonia (NH3) are gaining more attention. Mixtures of both fuels allow the adjustment of combustion properties. With future fuels also the vision of very clean combustion can be taken into the focus, being for instance based on lean premixed and for liquid fuels prevaporized combustion for gas turbines. For the utilization of such concepts, however, flame stability is essential. In this study the upper stability limits, i.e. lean blowout of turbulent hydrogen/ammonia/air flames, is experimentally investigated in a generic non-swirl premixed burner at atmospheric conditions. Special focus is laid on a measurement setup with fully automatized measurement procedure, to reach the stability limits, as these limits tend to depend for instance on the approach speed towards the limit. The ammonia content was varied from 0 vol% to 50 vol% in 10 vol% steps with the rest being hydrogen, for a broad range of fuel-air-equivalence ratios. The lean blowout limit is increasing almost linearly with increasing fuel-air-equivalence ratios, whereas with increasing ammonia content the limit is decreasing. Furthermore, a model for the lean blowout limits were derived, which is able to predict the acquired experimental data with high accuracy.

The Evolution of Compressor and Turbine Bladings in Gas Turbine Design

1967 ◽  
Vol 89 (2) ◽  
pp. 199-205 ◽  
Author(s):  
C. Seippel
Keyword(s):  
Steam Turbine ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Parallel Evolution ◽  
Axial Compressor ◽  
Expansion Turbine ◽  
The Stability ◽  
Turbine Design ◽  
The City

The author, having been associated with the construction of gas turbines from the first 4000-kw unit delivered in 1939 to the city of Neuchaˆtel to the present time, gives some personal views on the evolution of the axial compressor and turbine bladings which are the key elements to the gas turbines. The axial compressor was created to supply air efficiently for the supercharged “Velox” boiler. It made the evolution to the modern gas turbine possible. The main problems encountered were related to the stability of flow. An enormous increase of volume capacity was achieved in the course of time. The increase of pressure ratio made special measures necessary to overcome instability at starting. The expansion turbine started on the basis of steam turbine practice and underwent a parallel evolution to large capacities. Its particular problems are related to the high temperatures of the gases.

The Experimental Behavior of Premixed Flames in Tubes: The Effects of Diluent Gases

1980 ◽  
Vol 102 (2) ◽  
pp. 422-426 ◽  
Author(s):  
J. Odgers ◽  
I. White ◽  
D. Kretschmer
Keyword(s):  
Carbon Dioxide ◽  
Transport Properties ◽  
Gas Turbine ◽  
Reaction Rate ◽  
Laminar Flame ◽  
Laminar Flame Speed ◽  
Gaseous Fuels ◽  
Gas Transport Properties ◽  
The Stability ◽  
Stability Limits

One of the problems facing gas turbine users is the proliferation of gaseous fuels which may be available. These are so many that a comprehensive rig/engine study would be far too costly to undertake. The present studies represent an attempt to quantify the behavior of such fuels, in a simple environment. Measurements of the rates of flame travel and the stability limits have been made for propane/oxygen mixtures diluted with nitrogen, carbon dioxide, helium or argon. The results have been used to forecast the laminar flame speed of mixtures, and rates of flame travel for the various mixtures have been correlated with groups representative of reaction rate and gas transport properties.

Second-Generation Low-Emission Combustors for ABB Gas Turbines: Tests Under Full-Engine Conditions

1990 ◽  
Author(s):  
M. Aigner ◽  
A. Mayer ◽  
P. Schiessel ◽  
W. Strittmatter
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Second Generation ◽  
Test Facility ◽  
Low Emission ◽  
Preheating Temperature ◽  
Pressure Test ◽  
Flow Pressure ◽  
Stability Limits ◽  
Experimental Rig

An experimental rig was constructed which made it possible to research the influence of air mass flow, pressure, preheating temperature, and fuel/air ratio on the behavior of a full-scale burner. Because the investigations were carried out in the high pressure test facility at the DLR in Cologne, and not in a real gas turbine, the parameters could be varied independently of one another. Based on these systematic measurements, it is possible to predict flame stability limits and emissions for any gas turbine under any operating condition. For example, it can be shown that NOx emissions from the GT8 with ABB’s new second-generation premixing burners will not exceed 25 ppm (for 15% O2) and COwet will be less than 8 ppm at full load (16 bar, 420°C). In addition, the data measured were compared to results obtained from correlations frequently used, such as that NOx is proportional to p0.5. It was shown that this equation is too optimistic even if the flame type remains unchanged.

Characterization of ALM Swirl Burner Surface Roughness and its Effects on Flame Stability Using High-Speed Diagnostics

2019 ◽  
Author(s):  
Jon Runyon ◽  
Anthony Giles ◽  
Richard Marsh ◽  
Daniel Pugh ◽  
Burak Goktepe ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Gas Turbine ◽  
Gas Turbines ◽  
High Speed ◽  
Flame Stabilization ◽  
Flame Stability ◽  
Post Processing ◽  
Swirl Burner ◽  
Stability Limits ◽  
Near Wall

Abstract The use of metallic Additive Layer Manufacturing (ALM) is an active area of development for gas turbine components, particularly concerning novel combustor prototypes for micro gas turbines. However, further study is required to understand the influence of this manufacturing technique and subsequent post-processing on the resulting burner component surface roughness and its effect on flame stability. In this study, two Inconel 625 swirl nozzle inserts with identical bulk geometry (swirl number, Sg = 0.8) were constructed via ALM for use in a generic gas turbine swirl burner. Further post-processing by grit blasting of one swirl nozzle insert results in a quantifiable change to the surface roughness characteristics in the burner exit nozzle when compared with the unprocessed ALM swirl nozzle insert or a third nozzle insert which has been manufactured using traditional machining methods. An evaluation of the influence of variable surface roughness effects from these swirl nozzle inserts is therefore performed under preheated isothermal and combustion conditions for premixed methane-air flames at thermal power of 25 kW. High-speed velocimetry at the swirler exit under isothermal air flow conditions gives evidence of the change in near-wall boundary layer thickness and turbulent fluctuations resulting from the change in nozzle surface roughness. Under atmospheric combustion conditions, this influence is further quantified using a combination of dynamic pressure, high-speed OH* chemiluminescence, and exhaust gas emissions measurements to evaluate the flame stabilization mechanisms at the lean blowoff and rich stability limits. Notable differences in flame stabilization are evident as the surface roughness is varied, and changes in rich stability limit were investigated in relation to changes in the near-wall turbulence intensity. Results show the viability of using ALM swirl nozzles in lean premixed gas turbine combustion. Furthermore, precise control of in-process or post-process surface roughness of wetted surfaces can positively influence burner stability limits and must therefore be carefully considered in the ALM burner design process as well as CFD models.

scholarly journals Gas Turbine Spinning Reserve Operation to Support Frequency Drops in Small Grid

1998 ◽  
Author(s):  
Ismael Brito ◽  
Michael Dost ◽  
Axel W. von Rappard
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
Exhaust System ◽  
Spinning Reserve ◽  
Control Functions ◽  
Load Increase ◽  
The Stability ◽  
Grid Side ◽  
Gas Turbine Power Plant

The use of gas turbines in relatively small grids is often connected with an additional requirement from the grid side. Such a requirement can be the increase of power production within seconds to support the stability of a grid. This topic was investigated thoroughly in 1985 for several types of power plants. In 1992 ABB received an order for a gas turbine power plant on the island of Puerto Rico where a fast loading response with 40% load increase within 3 seconds was required. Based on earlier investigations the order was accepted. The powerplant built a „Steam Enhanced Power (SEP) plant“, each consisting of three powertrains each with a gas turbine, a once through steam generator and an exhaust system with an SCR for emission control. This paper describes the control functions necessary to meet the requirements and the consequences for the operation of the plant. Results from the acceptance tests where the rapid loading from a standby mode at 60% load was simulated will be shown and discussed in detail.

Development of an Improved Hybrid Burner: Initial Operating Experience in a Gas Turbine

1996 ◽  
Author(s):  
Bernd Prade ◽  
Holger Streb ◽  
Peter Berenbrink ◽  
Bernhard Schetter ◽  
Gottfried Pyka
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Operating Experience ◽  
Liquid Fuels ◽  
Inlet Temperature ◽  
Discharge Temperature ◽  
Auto Ignition ◽  
The Stability ◽  
Base Load

Hybrid burners have demonstrated proven reliability in the premixed combustion of both natural gas and liquid fuels. NOx emission levels below 10 ppmv (gas dry, 15% O2) have been achieved in gas turbine models V94.2, V84.2 and retrofitted predecessor gas turbines. With increasing turbine inlet temperature (increasing efficiency), the pressure ratio and compressor discharge temperature will rise and auto ignition will become more critical. Therefore the development of an improved hybrid burner was an obvious necessity. Compatibility of the new burner with existing gas turbines was a basic requirement. The new burner was tested in a 10 MW Gas Turbine equipped with a SIEMENS silo combustor and in a V64.3 GT in Dresden, Germany. The paper presents the development and results of on-site measurements of NOx and CO emissions. At base toad NOx emissions below 25 ppmv were obtained by the revised hybrid (HR) burner without any combustion driven oscillation (< 5 mbar) in the V64.3. Additionaly the stability of the premixed flame was improved, so that the operation range of premix mode could be increased by three percent of base load.

Establishing Operating Limits in a Commercial Lean Premixed Combustor Operating on Synthesis Gas Pertaining to Flashback and Blowout

2012 ◽  
Author(s):  
David Page ◽  
Brendan Shaffer ◽  
Vincent McDonell
Keyword(s):  
Natural Gas ◽  
Synthesis Gas ◽  
Gas Turbines ◽  
Key Factors ◽  
High Hydrogen ◽  
Lean Blowout ◽  
Stirred Reactor ◽  
Operating Limits ◽  
The Stability ◽  
Stability Limits

Operability issues such as flashback and lean blow out are phenomena that must be addressed for successful commercial operation of stationary gas turbines. The present work focuses on flashback and lean blow out of premixed jet flames in a combustor from a commercially available gas turbine operating on synthesis gas compositions. The issue of flashback is exacerbated when operating on fuels with high hydrogen content due to the increased reactivity of hydrogen, thus increasing the propensity for flashback. Operating margins for mixtures of natural gas and carbon monoxide in hydrogen are reported. The results interestingly demonstrate reduced stability for mixtures of H2/NG than for H2/CO. Increasing H2 percentage from 0% to 100% reduced blowout equivalence ratios from Φ = 0.63 to Φ = 0.29 for H2/NG and Φ = 0.42 to Φ = 0.29 for H2/CO. In addition, results obtained for inlet temperatures of 300K and 623K are compared and show an upward shift of the stability limits for higher preheats. Modeling of the experimental data using a perfectly stirred reactor predicts the effect of the addition of H2 to natural gas on the blowout limits. With regards to flashback some key factors that dominate the characteristics are identified and attempts to correlate data are carried out. The results show that lean blowout and flashback occur at the same AFT, regardless of preheat temperatures. AFT at flashback and lean blowout are compared to a more fundamental burner [1] with results indicating reasonable scalability.

Analysis of the Emission Reduction Potential and Combustion Stability Limits of a Hydrogen-Fired Gas Turbine With External Exhaust Gas Recirculation

2021 ◽  
Author(s):  
Nils Hendrik Petersen ◽  
Thomas Bexten ◽  
Christian Goßrau ◽  
Manfred Wirsum
Keyword(s):  
Power Generation ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Nox Emissions ◽  
Diffusion Type ◽  
Renewable Power ◽  
Net Zero ◽  
Renewable Power Generation ◽  
Stability Limits ◽  
Flame Behaviour

Abstract To mitigate its impact on global climate, the power generation sector must strive towards a transition to net-zero emissions of greenhouse gases. This can be achieved by a massive penetration of renewable power generation. However, a high share of renewable power generation requires dispatchable and flexible power generation technologies such as gas turbines to maintain the stability of power grids. To achieve net-zero green house gas emissions, gas turbines have to be operated exclusively with carbon-neutral fuels. Hydrogen is a promising carbon-neutral fuel, although it comes along with several challenges regarding stable combustion. A possible measure to stabilize hydrogen combustion is the partial external recirculation of exhaust gases (EGR). In a previous study, the authors presented a model-based thermodynamic analysis of an industrial gas turbine featuring EGR. The next step was to answer the question of whether the thermodynamically negative impact of EGR (i.e. lower thermal efficiency) is justified by positive effects, such as reduced NOx emissions or a more controllable combustion of hydrogen. By means of a simple 1-D flame approach, the present study provides further insight into the flame behaviour and stability limits during a fuel switch from natural gas to hydrogen. In a following step, the same approach is used to investigate the flame behaviour in an EGR environment at two recirculation temperatures. The results show that if a hydrogen-fired, diffusion-type combustor is combined with sufficiently high EGR ratios, NOx emissions are potentially in the order of a state-of-the-art diffusion-type combustor fired with natural gas. In addition, based on the calculated laminar flame speeds and extinction strain rates, the higher reactivity of hydrogen could potentially be controlled by employing EGR. However, relevant literature suggests that stronger dilution might be required to compensate for the additional impact of turbulence-chemistry interaction in real application which could lead to flame stabilization issues and higher NOx emissions. Moreover, considering the industry efforts to develop hydrogen-capable premixed-type combustors, the results show that EGR has no significantly positive influence on the reactivity of a premixed pure hydrogen flame. The question regarding the preferred EGR temperature is addressed but cannot be answered conclusively.

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